eChapters

The word ‘statistics’ has been derived from the Latin Word ‘Status’ which means ‘Political State’. The word statistics has been coined by Gottfried Aschenwall, a German Political Scientist. Ronald Aylmer Fisher is regarded as father of modern statistics. The word statistics has meaning both in plural and singular sense. In plural sense, it means quantitative/qualitative figures. For example, the area under food grains in different states of India, the production of guava in different states of India, germination percentage of seeds, etc.. In singular sense, it means as a subject i.e., method of dealing with the quantitative/qualitative information.

Statistics is defined as scientific method which deals with collection, organization presentation, analysis and interpretation of data. It is included under both science and arts. Statistics is used as a tool to obtain knowledge on other subjects of science.

Samples having size, n - 30 are known as large sample. For large values of n (i.e., for n - 30), almost all the distributions are very closely approximated by normal distribution. Thus in this case we apply the normal test, which is based upon the area property of the normal probability curve. Large Sample Test is also known as Z-test or SND (Standard Normal Deviate) test.

Atmospheric pressure is the force per unit area exerted on a surface by the weight of air above that surface in the atmosphere of earth. The gas molecules of the atmosphere are pulled towards the earth by the force of gravity and hence exert a force on earth surface. In most circumstances atmospheric pressure is closely approximated by the hydrostatic pressure caused by the weight of air above the measurement point. Atmospheric pressure inf luences other weather elements in a significant way. Small changes in air pressure may not be felt, but they are important for bringing a change in weather. Atmospheric pressure can be calculated as the summed weight of all gas molecules between a horizontal plane and top of the atmosphere and divided by the area of the plane. Low pressure areas have less atmospheric mass above their location, whereas high pressure areas have more atmospheric mass above their location.

FACTORS AFFECTING ATMOSPHERIC PRESSURE

Air pressure never remains constant. Air pressure is greatly influenced by air temperature, altitude, water vapour presence in the air, rotation of earth, etc. However, these factors are not independent of each other in affecting the atmospheric pressure.

Temperature: Hot air expands and exerts low pressure. Cold air contracts and exerts high pressure. Thus, increase in temperature decreases the air pressure. Places nearer to equator experience low pressure due to prevalence of high temperature. The air being cold and heavy throughout the year a high pressure belt is created in both polar regions.

Altitude: Pressure varies smoothly from the earth’s surface to the top of the mesosphere. The pressure depends on the density or mass of the air. The density of air depends on its temperature. The density of air decreases with increase in height so the pressure also decreases with increase in height. At low altitudes above the sea level, the pressure decreases by about 1.2 kPa for every 100 metres.

Water vapour: Water vapour content of air is low in cold areas than that in dry areas. Hence, moist air of high temperature in dry areas exerts less pressure compared to cold air.

The Laboratory Worker is Surrounded by Many Dangers such as from..........

Handling of infectious materials.

Handling of broken glassware.

Accidental spill of corrosive reagents.

Swallowing of corrosive reagents such as concentrated Sulphuric acid,

Hydrochloric acid, sodium hydroxide, trichloroacetic acid etc.

Swallowing of infectious specimen.

Inhalation of poisonous fumes.

Infection in the conduct of necropsies.

Potential hazards in the form of inflammable chemicals and gas leakages.

1. Bacterial (Prokaryote) Genome

The chromosome of most bacteria is a single super coiled double stranded circular DNA molecule. A complex packaging mechanism is necessary in order to ensure that the entire DNA is folded within the bacterial cell in a manner, which will not inhibit transcription nor allow entanglement of the two daughter strands to occur during replication (Highly condensed >10 mg/ml in region less than l ìm in diameter). This is achieved by two main mechanisms.

• First the DNA is folded into between 40-100 loops
• Second each of the quasicircles is it self super coiled independently of the others each loop are abolished by Ribonuclease.

Deoxyribonucleic remove the super helical nature of the loops, though limited treatment with this enzyme will attack only a small number of the loops and therefore leads to removal of only some of the super coiling. The intact folded chromosome or nucleoid can be isolated in the presence of non ionic detergents and high molarities of salt in two possible forms free and membrane associated. The free form which sediments at 1600-1700s consists of about 60%DNA, 30%RNA and 10%protein the bulk of which is the enzyme RNA polymerase. The membrane bound form contains an additional 20% of membrane-attached protein. Bacterial genome size ranges from 580 to 9900kbp, & the average gene size is constant from 900 to 1100bp of which 87-94% are protein coding (Rickettisa’s 76% and Borelia Plasmid’s 41% are exceptions).

Introduction

The primary tools used by the molecular biologists in manipulating DNA are restriction enzymes and other DNA/RNA modifying enzymes. Over the years, the number and uses of these enzymes have increased as new molecules have been discovered. Restriction endonucleases are bacterial enzymes that cleave double-stranded DNA. They are present in bacteria presumably to destroy DNA from foreign sources. By cleaving the foreign DNA at specific sites. The host bacterial DNA os protected from cleavage because specific recognition sites are modified, usually by methylation form methylase at one of the bases in the site, making the site no longer a substrate for RE cleavage. Host bacteria used to propagate cloned DNA in the laboratory arte usually mutant in the host restriction genes, thus their intracellular enzyme activities will not destroy the foreign recombinant sequences. The endonuclaase with its accompanying methylase is called a restriction modification (R-M) system.

At least four different kinds of R-M systems exist characterized on the basis of the subunit composition, cofactor requirements and type of DNA cleavage. Most characterized enzymes belong to type II class, together with type IIS class. They comprise the commercially available restriction enzymes used for DNA analysis and manipulation. Type I and Type III enzymes are relatively uncommon and a few additional enzymes fit none of the classes.

Among more than 3000 different enzymes isolated from bacterial strains many share common specificities. Restriction enzymes that recognize identical sequences have been called as isoschizomers.

RAPD stands for Random Amplification of Polymorphic DNA. It is a type of PCR reaction, but the segments of DNA that are amplified are random. The scientist performing RAPD creates several arbitrary, short primers (8-12 nucleotides), then proceeds with the PCR using a large template of genomic DNA, hoping that fragments will amplify. By resolving the resulting patterns, a semi-unique profile can be gleaned from a RAPD reaction.

No knowledge of the DNA sequence for the targeted gene is required, as the primers will bind somewhere in the sequence, but it is not certain exactly where. This makes the method popular for comparing the DNA of biological systems that have not had the attention of the scientific community, or in a system in which relatively few DNA sequences are compared (it is not suitable for forming a DNA databank). Because it relies on a large, intact DNA template sequence, it has some limitations in the use of degraded DNA samples. Its resolving power is much lower than targeted, species specific DNA comparison methods, such as short tandem repeats. In recent years, RAPD is used to characterize, and trace, the phylogeny of diverse plant and animal species.

A branch of anatomy that deals with joints or articulations in the body is termed as arthrology or syndesmology. A joint is an articulation or union formed by two or more bones or cartilages with the help of connective tissue. To form a joint, the long bones meet at their extremities e.g. joints of fore limb and hind limb. Joints of flat bones are formed by their borders or edges e.g. joint of bones of skull, the cranial and facial bones. The short bones and irregular bones form a joint by uniting at any of their parts or surfaces e.g. intervertebral joints.

Classification of joints

Joints are classified on the basis of their structure i.e. the kind of tissue material by which the bones are united, the other constituent parts that help in uniting the bones and the kind of movement performed at that joint. On this basis, the following three major types of joints exist in the skeleton of animal body.

A branch of anatomy that deals with muscles and their accessory structures is called as myology and the body system concerned with myology is called muscular system. The muscular system is composed of specialized cells called muscle fibres because of their shape in the form of fibre or spindle. The plasma of these cells contains myofibrils which are contractile elements that cause contraction of muscles in a definite manner under the influence of a stimulus which is a unique property of muscles. These cells together constitute the distinctive muscular tissue.

Classification of muscles

Based on their morphological and functional characteristics, there are three types of muscles in the body.

Smooth muscle: The muscular tissue in this type of muscles is constituted by masses of spindle shaped cells and they occur mainly in the walls of hollow visceral organs including glands, the vessels, eye ball and hair follicles. These are nonstriated muscles. Contraction in these muscles is weak but sustained and mostly consistent and rhythmic. The action of this muscle is involuntary i.e. not under the will.

Cardiac muscle: The muscle fibres of this muscle are arranged in irregular masses and they form cross striations. The ends of some fibres come in contact with the sides of others forming a kind of syncytium. This is a striated muscle and its action is involuntary. This muscle occurs only in the wall of the heart and the immediate proximal ends of the major blood vessels like aorta, venacava and the pulmonary veins.

The respiratory system is a complex biological system comprised of several organs that facilitate the inhalation of oxygen and exhalation of carbon dioxide (breathing) in living organisms. The major functions of the respiratory system is providing oxygen to the body cells and removing carbon dioxide from the body. In addition to this, the respiratory system helps in controlling body temperature (especially in dogs), eliminating water (as vapour) and assisting in voice production. The organs of respiratory system extend from nose to lungs. These consist of two major parts, the upper respiratory tract and the lower respiratory tract. The upper respiratory tract is comprised of nose, nasal cavity, the part of mouth, and the part of pharynx. The lower respiratory tract is comprised of the larynx, trachea, bronchi and lungs.

Nose

The nose is the externally visible part of the respiratory system. It forms the part of the face of the animal extending from the transverse level of eyes to the rostral end of the head. Exteriorly it is formed by the bones, muscles, cartilages and the skin. Internally it encloses the nasal cavity which is lined by the mucous membrane. The dorsal part of the nose (roof of the nasal cavity) is termed as dorsum nasi. It is formed by the nasal and frontal bones of the skull. The lateral parts are formed by the incisive, maxillary, lacrimal and zygomatic bones. Covering these bones externally is a muscular layer formed by the facial muscles running over these bones and acting on the upper lip and nostrils. The muscular layer is externally covered by the skin. The skin on the nose bears fine hairs except at the tip of the nose that is formed by the nostrils. The rostral end of the nose is formed by nostrils which provide entrance to the nasal cavity. The nostrils are supported by cartilages which are the dorsal and ventral extensions of the cartilage of the nasal septum. The main aim of the nose is to support and protect the nasal cavity.

Pituitary gland

The pituitary gland (hypophysis) lies at the base of the skull and is housed within a bony structure called the sella turcica in the body of the basisphenoid bone. It is a small pea shaped gland which is attached to the hypothalamus by the pituitary stalk. The pituitary gland has two distinct parts called the lobes. These are the anterior lobe (adenohypophysis) and the posterior lobe (neurohypophysis). The anterior lobe which is also called as anterior pituitary consists of five types of cells, each of which secretes different hormone or hormones. The types of cells, the hormones secreted by each type and the functions performed by them are narrated below.

Brain

The brain, a command centre of the body, is a complex organ. The substance of the brain is made of the grey matter and the white matter. The grey matter is often identified as cerebral cortex but other parts of the brain also contain the grey matter. Inside the brain, the grey matter is organized into large accumulations of neurons which are called the nuclei of the brain. Each nucleus is associated with a specific function. In addition to neurons, there is other type of cells the glial cells called neuroglia. The neurons are responsible for sending and receiving impulses or signals. The glial cells are nonneuronal and provide support and nutrition to neuronal cells, form myelin and facilitate signal transmission in the nervous system. The white matter is made of millions of nerve fibres that are coming from neurons and are going to establish communications with different parts of the brain and spinal cord. Since these nerve fibres are coated with myelin sheath around them these appear white and the area occupied by these nerve fibres become the white matter of the brain.

The brain has three basic components, the forebrain, midbrain and the hindbrain.

Fore brain: The forebrain (Prosencephalon) is the rostral portion of the brain. It consists of cerebrum (Telencephalon) and the thalamus, hypothalamus and pineal gland together constituting the interbrain (Diencephalon).

Mid brain: The midbrain (Mesencephalon) is the middle portion of the brain. It is in the centre lying between the interbrain and hindbrain. It consists of a cranial part of brain stem.

Hind brain: The hindbrain (Rhombencephalon) is the caudal most portion of the brain. It consists of remaining (caudal) part of the brain stem, the medulla oblongata (Myelencephalon) and the cerebellum and pons (Metencephalon).

Horse

The first cervical vertebra (atlas) of horse is more or less similar to that of ox with a few variations as below

The wings of atlas are curved ventrad and laterad. These are thinner than in ox but their borders are thick.

The wings present an additional foramen, the transverse foramen in the caudal part.

A faint groove on the ventral surface of the wing connects the transverse foramen to the intervertebral foramen.

Horse

The cutaneous muscle in horse is thin and incompletely developed in the superficial fascia. The cutaneous muscle of the facial region (cutaneous fasciei) is incomplete and poorly developed over the mandibular space and the massetor muscle. Rostrally it passes to the angle of the mouth and blends with the orbicularis oris. The cutaneous muscle of the cervical region (cutaneous colli) is situated along the ventral region of the neck.

The frontalis muscle is absent.

The orbicularis oris forms incomplete ring around the rima oris. The levator nasolabialis is less extensive and is divided into the superior and inferior branches. Between the two branches pass the dilator naris lateralis and levator labii superioris. The levator labii superioris extends from malar, lacrimal and the maxillary bones to the upper lip in a common tendon with the muscle of the opposite side. The zygomaticus is thin, short and weak. It arises from the fascia covering the massetor. The incisivus maxillaris muscle which is absent in ox exists in horse and it lies under the mucous membrane of the upper lip. It originates on the alveolar border of the incisive bone from the level of lateral incisor to the first premolar and it inserts to the upper lip. Its action is to depress the upper lip. The incisivus mandibularis which is also absent in ox exists in horse under the mucous membrane of the lower lip. It originates at the alveolar border of the body of the mandible from the level of lateral incisor to the first premolar and is inserted on the skin of the lower lip and the chin. Its action is to raise the lower lip. The incisivus maxillaris and the incisivus mandibularis muscles acting together cause the closing of rima oris. The depressor labii inferioris is thicker and extends further back. The buccinator is almost similar to that of ox.

The lymphatics of the head and neck region is comprised of the lymph nodes and the lymph ducts. The lymph nodes of the head are the parotid, pterygoid, mandibular, the lateral and medial retropharyngeal, and the rostral and caudal hyoid. The lymph nodes in the cervical region are the superficial and accessory superficial, cranial, middle and caudal deep cervical and the costocervical and subrhomboidal lymph nodes. The lymph from these lymph nodes is finally collected and carried to the common jugular vein by the tracheal and right lymphatic ducts.

Lymph nodes of head

Parotid lymph node

The parotid lymph node is large and elongated gland usually single but sometimes two small glands connected closely with each other by a fibrous tissue lying on the upper part of the lateral surface in the caudal half of the masseter muscle. It is ventral to the temporomandibular joint, partly or completely covered by the dorsal part of the parotid salivary gland and is situated lateral to the maxillary vessels and nerve. The afferent lymph vessels are received to this gland (node) from the muscles of head, ocular and auricular muscles, the parotid salivary gland, the gums, lips, appendages of the eye, ear, lacrimal gland, and from the bones of the head such as frontal, malar, nasal, maxilla, incisive, turbinate, mandible etc. The afferent from the parotid lymph node joins the tracheal duct of the corresponding side.

There are eight pairs of cervical spinal nerves in ox. The first of these emerges out through the lateral vertebral (alar) foramen of the atlas vertebra. The second through the lateral vertebral foramen (at the cranial border of the arch) of the axis vertebra and the eighth nerve emerges through the intervertebral foramen between the last cervical and first thoracic vertebra. The third to seventh nerves emerge through the corresponding intervertebral foramen. Each of these nerves divides into dorsal and ventral branch immediately after their exit from the vertebral canal through respective foramina. The dorsal branches are larger than the ventral except for the first and last two and most of them divide in to medial and lateral branches. They supply the dorsal (dorsolateral) cervical muscles, skin and the cervical part of the nuchal ligament. The ventral branches are distributed to the ventral cervical muscles and skin, The ventral branches of the last two cervical nerves are large.

Horse

The lumbar vertebrae in horse are six in number. The bodies of these vertebrae are shorter. The first three of them have a distinct ventral spine which subsides thereafter. The transverse processes increase in length from first to third or fourth and then diminish. The first one or two slightly curve caudad and the last two or three curve craniad and the third is at right angles. The caudal border of the transverse process of the fifth vertebra at its base has an oval concave facet which articulates with a convex facet on the cranial border of sixth vertebra. The sixth transverse process is thick at the base and thin, narrow at its free end. It is curved forward. It has a large concave facet on its caudal border by which it articulates with the corresponding facet on sacrum.

The sacrum of horse is formed by the fusion of five sacral vertebrae similar to that in ox. However, the fusion of the spinous processes is incomplete. On either side of the base of the each spinous process is a groove which presents the dorsal sacral foramen. There are four foramina on each side of the dorsum of the sacrum of horse. The ventral surface of sacrum of horse is not so deeply arched as that of ox. The wings of sacrum are prismatic. Each wing has a large oval convex facet for articulation with similar facet on the caudal border of the transverse process of last lumbar vertebra.

The coccygeal vertebrae are eighteen to twenty in number in horse. The laminae of the neural arch of the coccygeal vertebrae beyond fourth vertebra fail to meet dorsally.

The pelvic bone (os coxae) of horse is in general similar to that of ox. The gluteal line on the gluteal surface of the ilium is faint. The ilium is placed more obliquely. The articular surface of ilium is rough and large and extends nearly to the external angle. The internal angles of the ilium of opposite sides are more close to each other. The external angles are formed of four tuberosities each.

The ischium of the two sides meets at a greater angle because of which the pelvic floor is bowl like. The ischial arch is wide and shallow. The ridge on the ventral surface of ischium is absent. The tuber ischii is not trifid. The lower border of tuber ischii forms the ventral ischiatic spine. The ventral surface of pubis is crossed by pubic groove which leads to acetabular notch that transmits the pubic femoral ligament.

Horse

The testicles in horse are oval in form and they are comparatively smaller in size than those in ox. The long axis of the testicles is parallel to the body of the animal and hence the attached border of the testicle is dorsal while its free border is ventral in position inside the scrotum. The testicle of the stallion is about 10 to 12 cm long, 5 cm wide and about 6 to 7 cm thick. It weighs about 225 to 300 gm. The size of the left and right testicle varies and the left testicle is often larger than the right one.

The epididymis is adhered to the attached (dorsal) border of the testicle. The rest of the features of epididymis in horse are similar to those of ox.

The vas deferens of horse right from its origin from the tail of epididymis to its course up to the dorsal surface of the bladder it has a uniform diameter of about 6 mm. Thereafter, it forms a fusiform enlargement, the ampulla of the vas deferens and beyond the ampulla the duct abruptly reduces in size. The ampulla is about 15 to 20 cm long and its diameter is about 2 cm. The genital fold is wider and hence the two ducts apart from each other. The vas deferens and the duct of seminal vesicle open in a common ejaculatory orifice on each side of the colliculus seminalis.

The caudal vena cava is a large unpaired vein which receives blood from the pelvis, pelvic limbs, mammary glands (in females) and scrotum (in males), the abdominal walls, and the viscera of the abdomen and pelvis. It is formed under the body of the fifth or sixth lumbar vertebra by the union of two common iliac veins which in their turn are formed by the union of the internal iliac and external iliac veins of the corresponding side. It passes cranially in the sublumbar region lying slightly to the right of the median plane and to the right of the abdominal aorta. In the cranial part of the abdomen, it follows the abdominal surface of the diaphragm and is embedded in the liver prior to its entry into the thorax through the foramen vena cava in the diaphragm.

In its abdominal course, the caudal vena cava is related dorsally to the sublumbar muscles and right crus of the diaphragm, ventrally to the colon, pancreas and the liver, on its right to the right kidney and the right adrenal and on its left to the abdominal part of the aorta.

Tributaries of caudal vena cava

The common iliac veins are short vessels formed by the union of the internal and the external iliac veins. These are located at the level of the fifth or sixth lumbar vertebra. The left vein crosses the dorsal surface of the aorta to reach the vena cava.

Horse

Lymph nodes of the wall of abdomen and pelvis

The lumbar aortic lymph nodes extend from kidneys to the deep circumflex iliac vessels. These are not clearly distinguishable from the cranial and caudal mesenteric, renal, testicular or ovarian, uterine and iliac lymph nodes.

The internal iliac lymph nodes are placed at about the origin of the iliac arteries. The external iliac lymph nodes are several small nodes situated in the triangular space between the cranial and caudal branches of the circumflex iliac artery.

The deep (internal) inguinal lymph node is not abdominal in position. It is not situated at the pelvic brim. It is one of the group of the lymph nodes of the hind limb.

The superficial (external) inguinal lymph nodes are on either side of the penis and in front of the superficial inguinal ring in male and above the mammary glands as the supramammary lymph nodes in female.

The prefemoral lymph nodes are about a dozen small glands arranged in an elongated mass placed on the medial aspect of the cranial border of tensor fasciae lata and on the caudal branch of circumflex iliac artery.

Horse

The muscles of shoulder region namely the supraspinatus, infraspinatus, teres major, teres minor and coracobrachialis in horse resemble those of ox. The subscapularis muscle has only a single head of origin in horse as against three heads in ox. The deltoideus muscle has two parts of origin as that of ox but in horse its acromial part is named as cranial part and it arises from scapular spine and the scapular fascia instead of the acromion process. In addition to these muscles, the shoulder in horse is composed of one more muscle named as capsularis. The capsularis is a very fine narrow muscle arising from the caudal part of the rim of the glenoid cavity of scapula and is inserted on the caudal part of the neck below the head of the humerus by insinuating itself between the fibres of brachialis muscle. This muscle is peculiar to solipeds and it raises the capsular ligament of shoulder joint during flexion of the joint.

The muscles of arm in horse are in general similar to those of ox except the following minor differences. The tendon of origin of biceps brachii is adapted to the intertuberal (bisipital) groove. The tensor fasciae antibrachii is thin in front and wide below. The medial head of triceps brachii is less developed and extends from the middle of the medial surface of shaft of humerus. The anconeus is smaller and less voluminous.

Amongst the muscles of forearm and manus, the flexors of carpus especially the flexor carpi radialis, flexor carpi ulnaris and the ulnaris lateralis resemble those of ox. The pronator teres is either vestigial or completely absent. The medial digital extensor is absent. The extensor carpi radialis resembles that of ox. The common digital extensor arises in common with the extensor carpi radialis. Its tendon descends over the synovial capsule of the carpus, passes down the metacarpus and at the fetlock it receives two slips from suspensory ligament to form the broad ligament which is inserted to the pyramidal extensor process of the distal phalanx. The lateral digital extensor is smaller. It arises from humerus and radius. Its tendon is inserted to the prominence on the dorsal (cranial) aspect of the proximal extremity of the proximal phalanx. The extensor carpi obliquus is inserted to the head of the medial small metacarpal bone. The superficial digital flexor does not divide into two parts. Its tendon is reinforced above the carpus by a strong fibrous band- the superior check ligament. The ring for the deep digital flexor is formed entirely by the tendon of superficial digital flexor. The deep digital flexor has same heads of origin as those of ox. Its tendon receives about half way down the metacarpus the inferior check ligament. It is inserted to the semilunar crest and tendinous surface of the distal phalanx.

Brachial plexus (FIG. 5-5 A)

The fore limb is supplied by nerves that extend from the brachial plexus. The brachial plexus is a large wide, flat and thick fascicular anastomosis of nerves formed by the convergence of ventral branches of last three cervical and first two thoracic spinal nerves in ox. It is placed between the scalenus muscle on the lateral wall of thorax and subscapularis and deep pectoral muscles on the costal (medial) surface of the scapula. From this plexus extend the following eleven branches (nerves) which are distributed mainly to the fore limb (thoracic limb) and most of the muscles of the thoracic girdle.

The main arterial trunk that supplies blood to the hind limb is the external iliac artery. As this trunk passes down through different segments (regions) of the limb it is differently named according to that segment or the region. In the abdomen it is named as iliac, in the thigh region as femoral, in the leg region as tibial and popliteal and down that the metatarsal artery and lastly the digital.

External iliac artery

The external iliac artery arises from the abdominal aorta ventral to the fifth or sixth lumbar vertebra. It descends at the side of the pelvic inlet ventrally and caudally along the tendon of psoas minor, crosses the tendon, reaches the cranial border of the pubis, gains the space between the sartorius and pectineus muscles and then continues in the thigh (femoral region) as the femoral artery. In this course it is covered by peritoneum and is related laterally to the psoas minor, sartorius and iliacus muscles, medially to the common iliac vein and caudally to the external iliac vein. The following are the collateral branches of the external iliac artery.

Sites for surgical interventions

Luxation of patella in cattle and horses

The luxation of patella is a condition wherein the patella of the stifle joint (femoropatellar articulation) is locked above the medial ridge of the trochlea of the femur.

Anatomy of femoropatellar articulation of the stifle joint

The stifle joint is a composite joint formed in two parts. One of these is an articulation between the condyles of distal extremity of femur and the condyles of the proximal extremity of tibia (femoro-tibial articulation) and the other is the articulation between the trochlea of the distal extremity of the femur and the articular surface of the patella (femoro-patellar articulation).

The trochlea of the femur consists of two asymmetrical ridges separated by a groove. The medial ridge is more prominent, wider and a little more extended dorsally than the lateral ridge. The two ridges converge ventrally. The articular surface of the patella is more or less quadrilateral or triangular with the base above and apex below. It has a vertical ridge in the middle and it separates the two concave areas of which the medial one is larger than the lateral. The patella is fastened against the trochlea with the help of three types of ligaments. One of these is the capsular ligament which is attached to the periphery of the articular areas of the two segments of the joint. The other one is the medial and lateral collateral ligaments. The third set of ligaments is the patellar (straight) ligaments.

All due precautions have to be exercised in handling pesticides because many of these leave toxic residues on treated food materials and plants which accumulate in higher concentrations in animals which consume these.

General Precautions

Read the precautions given by the manufacturer of the pesticides carefully. Store the pesticides under lock and key; prevent access of children to these; empty containers must be disposed off safely.

Blood and skin contaminations must be avoided.

The godown for fumigation must be made airtight by closing the doors, windows, ventilators, crevices etc.

In case of fumigation, the operator must use a suitable gas mask. It is a face-piece connected to a canister containing an absorbent material for the vapours of the fumigants by means of a flexible non-kinking breathing tube and provided with valves so that all air inhaled by the user passes through the canister and the exhausted air passes directly to the outside atmosphere through a non-return valve. The absorbent canister carries instructions indicating the number of hours for which it is effective in an atmosphere charged with the fumigant.

After the required exposure period, aerate the godown thoroughly. First open the entrance door, keep it open for 6-7 hours, then only enter and open other doors or windows.

Insecticide resistance to both fumigants and contact insecticides is an increasing problem in controlling stored grain and grain product insects throughout the world (Table 14.1). Hence, persons engaged in food commodity storage and preservation world over are concerned about the resistance of stored product insects to contact insecticides and fumigants. It is, therefore, necessary to work out strategies to delay or minimize the probability of resistance evolution. Resistance to pesticides is the ability of a strain of insects to tolerate doses of toxicants which would prove lethal to a normal population of insects of the same species. Resistance results when occasional resistant individuals arise in a population and survive the pesticidal treatment. These survivors then reproduce and confer the resistance to their offspring in succeeding generations. Resistance is the ability of a population (of insects) to survive a dose (of insecticide) that would normally kill 100 per cent of a susceptible population. Insecticide resistance is a dynamic phenomenon dependent on biochemical, physiological, genetic and ecological factors.

The chances of development of insecticide resistance in stored grain insect pest are more because of their life style, i.e., to remain confined in limited area. This results in more common inbreeding of the homozygous resistant strain resulting into homozygous resistant progeny. At the same time their management, once detected, can be easily achieved with the application of sufficiently acceptable sufficiently higher dose of the most appropriate insecticide to eliminate all the resistant survivors

The insect pest of stored grains can be conveniently divided into two groups, i.e., coleopterous and lepidopterous, therefore, the subject on these two groups has been pooled accordingly.

Objectives

• To study working principles of simple microscope
• Study different parts of simple microscope

Introduction

This is the first ever microscope. It was founded by Leeuwenhoek in 17^th century. He combined a convex lens with a specimen holder, for seeing the magnified images of small objects. It looks like a magnifying glass because it has the capacity to magnify between 200 and 300 times. A simple microscope is a small focal lens used to view the magnified images of small objects. It is just like a hand lens and glass with relatively lower magnification power.

This method has been first described by H. H. Lowe in 1927. This is the most widely used method to handle segregating generations following crosses between two parents to develop new cultivars combining desirable traits from both the parents. In this method, superior types are selected in successive segregating generations and a record is maintained of all parent-progeny relationships. The records help the breeder to advance only progeny lines with plants that exhibit genes for the desired traits. Selection begins in F2 generation where individual plants are selected which in judgment of breeder will produce the best progeny in F5/F6 when the selection is finally concluded. In F3 and F4 generations, many loci will have become homozygous and family characteristics begin to appear. By F5/F6 generation, most families are expected to be homozygous and uniform and hence selection within such families is no longer effective. At this stage selection emphasis shifts to the selection among families rather than within families.

Selection of parents is of great significance for the success of this method. Normally, this method is used to replace already established variety. Therefore, one parent should be selected on the basis of proven performance in the particular area where the breeding is in progress. The second parent should be such that it complements the first parent for the character under improvement. Sometimes, three or four parents may also be used to supply the desired character by way of three-way or double crosses.

The application of back-cross breeding first proposed by H. V. Harlan and M. N. Pope in 1922 provides a precise way of improving varieties that excel in a large number of attributes but are deficient in a few key characteristics. F. N. Briggs too started an extensive back-crossing programme to develop bunt resistant varieties of wheat in 1922. As the name implies, the back-cross method of breeding makes use of a series of back-crosses to the variety to be improved during which the character or characters in which improvement is sought is maintained by selection. At the end of back-crossing, the gene (or genes) being transferred will be heterozygous. Selfing at the end of last back- cross produces homozygosity for this gene pair and coupled with selection will result in a variety similar to the well adapted and recurrent parent but superior for the particular characteristic for which improvement programme was initiated.

In back-cross method of breeding, the adapted and highly desirable parent is called the recurrent parent and the source of desirable character being transferred is called as donor parent. It is most effective and easy to apply when the missing trait is qualitatively inherited, dominant and produces a phenotype that is readily observed in a hybrid plant. The procedure for transferring a recessive trait is similar to that for dominant trait but involves an additional step of selfing. Back-crossing is also used to transfer entire sets of chromosomes in a foreign cytoplasm to create a cytoplasmic male sterile (CMS) genotype as has been practiced in maize, onion and wheat, etc. This is done by crossing the donor (of chromosomes) as male until all donor chromosome are recovered in the cytoplasm of the recurrent parent. Back-cross breeding has also been used to develop isogenic lines (lines that differ only in alleles at a specific locus) for traits like disease resistance and plant height, etc.

Mangelsdorf (1951) has opined that hybrid corn has been the most far-reaching development in applied biology. Hybrid cultivars have contributed enormously to world’s food and feed resources. Although dramatically successful at first in corn, hybrids have spread to several other crops both in cross-pollinated and self-pollinated species. Their use is likely to spread more in time to come. Hybrid varieties are those in which F1 populations are used to produce commercial crop. Parents of F1 may be inbred lines, clones, varieties, or other populations. Hybrid breeding is historically rooted in development of hybrids in corn and therefore most of the issues covered in this section relate to hybrid breeding in maize.

Genetics and Gene

Genetics is defined as the branch of biology dealing with heredity and variation. The hereditary units which are transmitted from one generation to the next are called genes. Genes have been defined in various ways. These are units of inheritance located in linear order on chromosomes. The genes are considered as hereditary determinants of a specific biological function located in a fixed place on the chromosome. Chemically, gene is a segment of DNA (deoxyribonucleic acid) encoding one polypeptide and defined operationally by the cis-trans or complementation test. Gene is the functional unit of inheritance (a sequence of DNA) which is located on a certain position (locus, plural loci) on a chromosome. The locus is sometimes used interchangeably for gene. DNA, in conjunction with a protein matrix, forms nucleoprotein and becomes organized into structures with distinctive staining properties which are known as chromosomes. The chromosomes are located in the nucleus of the cell. Since genes are located on the chromosomes, in many ways behavior of genes is parallel to the behavior of the chromosomes. Two or more alternative forms of a gene are called as alleles. All genes on a chromosome are said to be linked and they all belong to the same linkage group.

6.1 INTRODUCTION

The ultimate success of an orchard enterprise largely depends upon the quality and genuineness of planting materials as nursery plants are the foundation of the orchard. Fruit crops, mostly being perennial in nature, call for utmost care in selection of cultivar, quality planting material and adoption of right technology for mass multiplication of planting material. Mistakes committed during the initial establishment of orchards cannot be corrected and will cause serious damage to production and productivity. The variation of scion-wood and rootstock has great bearing on the productivity of an orchard. Thus, it is of immense importance having all plants carefully labelled or otherwise marked. Cuttings taken from the mother plant will grow to have the same genetic qualities as the original plant. This is why the plants resulting from these cuttings are called “clones”. When a stem cutting is taken from a mother plant, the piece of stem will produce new roots if it is properly hydrated. Additionally, some plants can be grown from leaf pieces, or leaf cuttings and these will produce both stems and roots.

Thus, the progeny trees are the basic component for the multiplication of fruit plants and ultimately deciding the quality and productivity of the fruit crops. Hence, it is necessary to stock the true to type and best quality progeny trees.

In asexual methods of plant propagation, plant parts are being used as propagating materials. The plant from which the plant parts are collected is known as mother plant. There is every possibility of transmission of disease or pest which is present in the mother plant to the progeny. The mother plants have to be maintained properly to obtain disease free planting materials so that multiplication of disease/pest can be prevented. Thus, there is a need for the establishment of mother plant block/scion banks.

It 9001:2000 Means customer satisfaction and continuous improvement

ISO (International Organization for Standardization) is a worldwide federation of national Standards bodies from each country. The object of ISO is to promote the development of Standardization and related activities in the world with a view to facilitating international exchange of goods and services, and to developing cooperation in the spheres of intellectual, scientific, technological and economic activity. The results of ISO technical work are published as International Standards.

Quality management Systems (QMS) certification as per ISO 9001 : 2000 is an important opportunity that can enable the companies acquire the label of an enterprise caring for the customer needs and improve their economic performance at the same time. QMS provides an organization a systematic structured documented and effective approach to consistently maintain the product quality meeting customer requirements.

3.1 Introduction

India, when gained independence in 1947, was predominantly an agrarian economy, with a stagnant national income. The country inherited a weak industrial base, restricted to only a few industries. Agricultural growth was virtually negligible, the country had a stagnant cropped area where by only a very small proportion of agricultural land was irrigated. On the eve of the country’s independence, on 15^th August 1947, Jawaharlal Nehru, India’s Prime Minister, reminded the country that the task ahead included ending poverty, ignorance, and disease and inequality of opportunity. India began the process of planning with the launching of the 1^st five-year plan in April 1951. The central purpose of planning was to ‘initiate a process of development which would raise living standards and open out to the people new opportunities for a richer and more varied life’. Afterwards, the five-year plans were formulated seeking development in a sustainable manner.

The country, over the past has travelled a long way indeed in its drive towards economic growth, modernization of the economy, feudal economy at the time of independence has been transformed into one based on a fairly developed and diversified industrial structure and a sound agricultural base with a large potential for further industrialization and development. The income and consumption levels of people, on an average, have increased and the consumption basket has diversified. A noteworthy achievement indeed has been the elimination of famines with which the country continued to be afflicted right until independence. That achievement is far from negligible since many other countries in Asia and Africa are yet to free themselves of this malady. There is also other achievement, varying from the successful functioning of a democratic system to the emergence of a strong and large scientific community (Dreze Sen, 1995). The figure 3.1 shows the per capita income during 1997-1998. It shows that the maximum income from Northern India compared to Southern India. However, having adapted the pattern of economic development that brought prosperity to the Western, India has also seen widespread environmental damage and degradation in the pursuit of economic growth. The concern for preserving the environment against the onslaught of industrial expansion, intensification of agricultural, and adoption of a resource-intensive lifestyle has not been given the attention it deserved, and the costs of environmental degradation have not been internalized in the development process. While the Indian economy study made by two World Bank staffers shows that the country is paying an enormous price for this onward march, which has brought in its wake ecological devastation and numerous health problems.

15.1 INTRODUCTION

Curry leaf is an important perennial tree vegetable cum spice crop of India mostly used in South Indian culinary preparations for flavouring food stuff. It is an underexploited crop. The leaves have slightly pungent, bitter and feebly acidic taste and they retain their flavour and other qualities even after drying. Curry leaf is used in many of the Indian Ayurvedic and Unani prescriptions. It has many industrial values and medicinal uses. Its leaves, roots and bark are credited with tonic, stomachic and carminative properties. Leaves are reported to cure piles and allay heat of body. The green leaves are said to be eaten raw for treatment of dysentery. External application of pulped bark and root is reported to relive eruptions and bites of poisonous animals. An injection of toasted leaves is used to stop vomiting. The tribal people of India use its ground bark to rub on the bitten Part As a snake bite remedy. The powdered leaves are also used to aid in healing of fresh cuts. The dried curry leaf powder is also a good spice powder for use in the food stuff preparation and is exported. Fresh leaves on a steam distillation under high pressure yield 2.6 % (curry leaf oil) volatile oil which is used as fixative for heavy type of soap and perfume. Rectified leaf oil is deep yellow in colour with a strong spicy odour and pungent clove like taste. A volatile oil, a crystalline glucoside ‘Koenigin’ from the leaves and ‘Murayam’ from the flowers are industrial products. Curry leaf is grown on large scale in West Bengal, Assam, Deccan plateau, Western Ghats, Tamil Nadu, Karnataka and Kerala. It is cultivated in Coimbatore, Salem and Tiruchirappalli districts of Tamil Nadu on a commercial scale.

18.1 INTRODUCTION

Sorrel is a perennial herb, which is found in grassland habitats throughout Europe from the northern Mediterranean coast to the north of Scandinavia and in parts of Central Asia. It is of two types such as Garden sorrel that is a native of Europe and south western Asia and French sorrel that is originated in the mountains of southern France and the southern and central regions of Europe and south-west Asia. The name sorrel is derived from the Germanic word, Sur and the old French word Surele, both meaning sour. It is primarily used as a culinary herb for its leaves, which are used in salads too. The leaf of this plant resembles that of spinach and have a lemony lettuce flavour and the plant is well known for strong acidity in Europe and the United States. Sorrel is a rich source of potassium, iron and vitamins A, B₁ and C. The flavour of sorrel leaves is mainly due to oxalic acid, which is harmless when consumed in small amount. Owing to high level of vitamin C content, it was rightly believed to protect against scurvy disease. It is a dioecious plant, that bears unisexual flowers, as the male and female flowers appear on different plants. When the plant flowers, they look very attractive and are often used as an ornamental plant.

18.2 CHOICE OF CULTIVARS

In India, it is not a common leafy vegetable and is grown on a limited scale, mostly in kitchen gardens. Even in Europe and other countries, different local strains are grown for both home gardening and commercial cultivation. Profusion is a cultivar, which mutated naturally in France and produces only leaves without forming seed, and hence, the plant always has fresh and ready to pick leaves.

Dolichos bean is known as Lablab bean, hyacinth bean or sem. Grown as field crop in MP, Maharashtra, AP and TN. Genus Dolichus is renamed as Lablab (Syn. D. lablab, D. purpureus, Lablab niger, L. bvulgaris) and Lablab purpureus name is widely accepted. Dolichos lablab L. (synonyms Lablab purpureus (L.) Sweet.) is leguminous pod vegetable grown in tropics and few temperate countries. Lablab niger var. lablab is synonym to Dolichos lablab var. typicus where long axis of seed is parallel to suture and is vegetable type. Lablab niger var. lignosus synonym to Dolichos lablab var. lignosus where long axis of seed is perpendicular to suture and is pulse type.

Growth: Growth involve cell division subsequently cell elongation. Increase in volume that is associated with fruit growth largely result of cell division or cell elongation or both. In some fruit such as apple, extension of intercellular space may also contribute the growth. Generally growth by cell division in early stage whereas, cell elongation during later stage.

Two distinct type of growth curve are observed when increase in such variable such as fresh weight, volume and dry weight of fruit.

1. Single sigmoid curve
2. Double sigmoid curve

In case of single sigmoid growth curve firstly there is rapid increase in size then after decline so there is only one rapid growth is observed e.g. Apple, pear, tomato, cucumber and strawberry.

In case of double sigmoid two rapid growth period are separated by an intermediate period that is less growth or no increasing growth curve. Double sigmoid growth curve can be used as two successive sigmoid curve thus there are three clearly define stage of growth.

Banana (Musa sp), is consumed both as a fruit and vegetable. The sweet desert cultivars are generally called bananas and the starchy cooking types are called plantains. It is an important food crop throughout the tropics. References to the banana is frequently made in the Vedic literature, where its use in religious rituals is quite common. Today, it is a leading tropical fruit in the world market with a high degree of export potentiality. Bananas arrives at the world markets the year round. Though India is the largest producer of banana in the world, Ecuador, Hondurus, Columbia, Costa Rica, and Panama are the leading banana exporter, while USA, Japan, Germany, France and UK are the main importing counties.

Banana is believed to have originated in the warm moist tropical regions of SouthEast Asia. Its cultivation is confined to region between 30° N and 30° S of Equator. Banana is grown in many countries namely India, Philippines, Thailand, Uganda, Zaire, Tanzania, Ivory coast, Burundi, Columbia, Brazil, Ecuador, Venezuela, Bangladesh, the Caribbean Islands, the canary Island, USA(Florida), Egypt, Australia, Sri Lanka.

Banana belongs to the family Musaceae and genus Musa. There are several species of Musa which involves both dipoilds and triploids. Most of the cultivated bananas are triploids. They are further classified based on their genomic status. Bananas and plantains are today grown in every humid tropical region and constitute the 4th largest fruit crop of the world, followed by the grape, citrus fruits and the apple.

Varieties/Cultivars: Though there are more than 25 different kinds of bananas grown in India, Grand Naine, Robusta, Poovan, Ney poovan, Rasthali, Karpuravalli, Tellachakrakeli, Red Banana, Nendran, Monthan, Batheesa, Hill Banana (Veerupakshi & Sirumalai) are the popular varieties grown all over the country with different local names.

The carambola, Averrhoa carambola L., is believed to have originated in Malaysia and the Molucca but it has been cultivated in southeast Asia for many centuries. It belongs to the family Oxalidaceae. The carambola, Averrhoa carambola L., is usually called balimbing, belimbing, or belimbing manis (“sweet belimbing”), to distinguish it from the bilimbi or belimbing asam, A. bilimbi L. In Ceylon and India, the carambola has the alternate names of kamaranga, kamruk, or other variants of the native kamrakh.

Cultivars/Varieties: Sweet and sour forms are recognized a cultivar in India. In countries like Australia, Japan, Taiwan and, USA named cultivars are grown.

Uses

Fruits are mainly used for dessert purpose. Slightly unripe fruits are used for jelly and pickle. Unripe fruit is also used for dying as it contains potassium oxalate. It is a popular substitute for tamarind in cooking. The acid types of carambola have been used to clean and polish metal, especially brass, as they dissolve tarnish and rust. The juice will also bleach rust stains from white cloth. Unripe fruits are used in place of a conventional mordant in dyeing. Carambola wood is white, becoming reddish with age; close-grained, medium-hard. It has been utilized for construction and furniture.

Kokum (Garcinia indica L.,) is an evergreen tree found in the tropical forests of India. It is a plant in the mangosteen family (Guttiferae), and is a fruit tree that has culinary, pharmaceutical, and industrial uses. The extract/concentrate of this fruit is called aagal in Konkani and Marathi. It is used for preparation of sol kadhi when mixed with coconut milk. The outer cover of fruit is dried in the sun to get aamsul or kokam. It is used as a souring agent in recipes from Maharashtra. It is a preferred substitute for tamarind in curries and other dishes from Konkan. It is also used in Konkani cuisine, in Gujarat, and some cuisines of South India. As kudam puli, it is an essential ingredient of traditional fish recipes of Kerala. It is particularly seen in Karnataka, Maharashtra, Gujarat, Goa, Kerala, Assam and West Bengal.

Uses

The acidic sweet fruit is mainly used as souring agent for vegetable curry and dal. Sun drying is practiced for preservation. Dried Kokum fruit rinds are widely used in cooking as they impart a sweetish-tangy flavor to the food. The fruits contain citric acid, acetic acid, malic acid, ascorbic acid, hydroxycitric acid and garcinol. Fresh are cut in to halves and the fleshy portion containing the seeds is removed. The rind which constitutes about 50 per cent of the fruit is repeatedly soaked in the juice of the pulp during sun drying. It makes excellent beverage with pleasant flavour. Kokum butter is a product of commerce obtain from seed. It is also used in soap and candle making and suitable for ointment and other pharmaceutical preparations. This fruit is known to reduce obesity and regulate blood cholesterol level.

The loquat, Eriobotrya japonica Lindl., (syn. Mespilus japonicus Thunb.), belongs to the rose family, Rosaceae. It is also called Japan, or Japanese plum and Japanese medlar. The loquat is indigenous to southeastern China and possibly southern Japan, though it may have been introduced into Japan in very early times. It is said to have been cultivated in Japan for over 1,000 years. Cultivation spread to India and southeast Asia, the medium altitudes of the East Indies, and Australia, New Zealand and South Africa. Chinese immigrants are assumed to have carried the loquat to Hawaii.

The loquat fruits are round, oval or pyriform, pale yellow to orange in colour and are borne in loose clusters. The flesh is firm, meaty or melting, deep orange in colour, juicy and sub acidic in flavour.

Cultivars/Varieties: There are two groups of loquat cultivars – Chinese and Japanese. The Chinese type are large, pyriform and deep orange in colour, while Japanese type is smaller, light coloured and sometimes slender in form. The well-known cultivars are California Advance, Tanaka, Thales, Pyriform, Golden yellow, Improved golden yellow, Pale yellow. Other named cultivars are Improved Pale yellow, Fire Ball, Large Round, Gold Nugget, Safeda and Mammoth.

Uses

Loquat is commonly eaten as a fresh fruit. Loquat can also be processed into several products like jam, jelly and chutney. Seeds are usually taken out from the fruits, otherwise they may impart a bitter taste. The fruits are also used in gelatin desserts or as pie-filling, or are chopped and cooked as a sauce. Loquats canned in syrup are exported from Taiwan. Some people prepare spiced loquats (with cloves, cinnamon, lemon and vinegar) in glass jars. The fruit is also made into jam and, when slightly underripe, has enough pectin to make jelly.

The pineapple is the leading edible member of the family Bromeliaceae which encompasses about 2,000 species, mostly epiphytic and many ornamentals. Pineapple (Anans comosus (L) Merr), belonging to the family Bromeliaceae, is one of the most important commercial fruit of the world. Its pleasant characteristic aroma and taste make it a choicest fruit both for fresh consumption and processing.

Now known botanically as Ananas comosus Merr. (syns. A. sativus Schult. f., Ananassa sativa Lindl., Bromelia ananas L., B. comosa L.), the fruit has acquired few vernacular names. It is widely called pina by Spanish-speaking people, abacaxi in the Portuguese tongue, ananas by the Dutch and French and the people of former French and Dutch colonies; nanas in southern Asia and the East Indes. In China, it is po-lomah; in Jamaica, sweet pine; and in Guatemala often merely pine.

The region which includes Central and Southern Brazil, northern Argentina and Paraguary, is believed to be the place of origin of Pineapple. From here it has spread to all countries of the tropic and some parts of the sub-tropics. It has been introduced to India in 1548. The major pineapple producing countries of the world’s are Hawaiian, Island, Philippines, Malaysia, Thailand, Brazil, China, Kenya, Mexico, Taiwan, South Africa, Australia, India and Indonesia.

Cultivars: Kew or Giant Kew, Queen, Mauritius, Cayenne, Red Spanish, Singapore Spanish, Haricharanvita, Charlotte, Rothchild. In Assam there are two indigenous varieties–Jaldhup Desi and Lakhat, both of which fall in Queen group.

Plum belongs to the genus Prunus under family Rosaceae. The European plum are Prunus domestica and Japanese plums are Prunus salicina and hybrids. Mature plum fruit may have a dusty-white coating that gives them a glaucous appearance and is easily rubbed off. This is an epicuticular wax coating and is known as “wax bloom”. Dried plum fruits are called dried plums or prunes, although prunes are a distinct type of plum, and may have pre-dated the fruits now commonly known as plums. The major plum producing states are Himachal Pradesh, Jammu & Kashmir, Mizoram, Punjab, Tamil Nadu (Ooty) and Uttarakhand.

Cultivars/Varieties: Damson plum, Greengage plum, Mirabelle plum, Victoria plum, Satsuma plum and Yellow plum.

Uses

Plums are mainly used consumed as fresh fruits. They are also used widely for making jam, jelly chutney and squash. Certain varieties of European plum are specially suited for drying to produce prunes. Prunes are firm fleshed fruits of P. domestica cultivars having sugar content which can be dried whole without fermentation around the pit, to make a firm tasteful product that can be stored for long period.

Pomegranate (Punica granatum L.) belongs to the family Punicaceae and is one of the favaourite table fruits of tropical and subtropical regions. The fresh fruit is of delicate quality while its processed products are highly appreciative. It is now extensively grown in Arid regions. Pomegranate is in fact native to Iran and is extensively cultivated in Mediterranean countries. It is distributed in Spain, Morocco, Egypt, Afghanistan, Arabian countries, Pakistan, Myanmar, China, Japan, Chile, Argetina, Mexico, USA, Bulgaria, Italy, India and Iraq.

Cultivars: Important pomegranate varieties cultivated in India are Bhagwa, Ganesh, Alandi or Vadki, Dholka, Kandhari, Kabul, Muskati Red, Paper Shelled, Spanish Ruby, Ganesh (GB I), G 137, P 23, P 26, Mridula, Aarakta, Jyoti, Ruby, IIHR Selection, Yercaud 1 and Co 1.

Uses

The pomegranate is commercially grown for its sweet acidic taste arils. The fresh fruit has exquisite quality, while its processed products such as bottled juice, syrups and jelly are highly appreciated. Pomegranate is a delicious fruit consumed for its medicinal value. Its juice is sweet with pleasant aroma and is refreshing. The fruit is widely used for Ayurvedic and Unani medicines. Some of the commercial products of pomegranates are juice, squash, syrup, jelly. Anardana is obtained by drying the seed along with pulp and sun. The rind is used as a valuable tanning material. The flowers yield a red dye.

Fragaria is a genus of flowering plants in the rose family, Rosaceae, commonly known as strawberries for their edible fruits. It is a low perennial creeping herb which is widely grown in temperate and subtropical regions of the world.

There are more than 20 described species and many hybrids and cultivars. Cultivated strawberries are based on two species, Fragaria chiloensis (L) Duch., native to the west coast of North America and Fragaria virginia Duch., native to eastern coast of North America. Hybrids of these two species are ancestors to all the modern strawberries. The most common strawberries grown commercially are cultivars of the garden strawberry, a hybrid known as Fragaria × ananassa. Strawberries have a taste that varies by cultivar, and ranges from quite sweet to rather tart. Strawberries are an important commercial fruit crop, widely grown in all temperate regions of the world.

The major producers of strawberries are USA, Mexico, Poland, Japan, Italy, Israel, Australia, New Zealand and Turkey. In India it was introduced during 1960’s and is grown to a limited extent in Jammu & Kashmir and Himachal Pradesh and some parts of southern India (Karnataka and Ooty).

Cultivars/Varieites: Tioga, Tufts, Surecrop, Fresno, Toro, Heidi, Hood, Northwest, Puget Beauty, Olympus, Ozark Beauty.

Style of garden holds a distinctive appearance, typically determined by the principles according to which gardening can be worked out. There are basically four styles of gardening that are followed to establish any garden. Brief of them are given below.

The various adverse effects of Shifting cultivation, the need for its replacement have been widely discussed at various levels. It has been a matter of concern not only for the Government of India and the Planning Commission but also to the various state governments and the union territories of the region. Although considerable data on the extent of Shifting cultivation and its various adverse effects including its effect on agricultural production have been discussed in various forums, yet detailed scientific studies on shifting cultivation from various angles were not taken up until recently. The prevalence of shifting cultivation is so extensive in the region that it would not be possible to tackle the problem within a short period of time whatever, large the efforts may be. It will, thus, be necessary to approach the problem so that alternative systems of farming can be introduced in areas where the cycle of rotation has been greatly reduced.

Agriculture is an important economic activity for a large population of the developing world. The view that industrialization is the main hope of the developing countries has undergone remarkable changes in more recent times. Today, agriculture and rural development are viewed as the sine qua non of national development. A reorientation where in rural development is well balanced with industrial growth is now considered essential to correct serious imbalances in the economy, for equitable distribution of wealth and for social justice. It is against this background that increases in agricultural production in the developing world need to be viewed and evaluated.

Introduction

Shifting cultivation, developed over centuries of experience is known as “Swidden”, “Slash-and–burn agriculture”, “Rotational bush-fallow agriculture.’ or by a variety of local names; in India, it is commonly referred to as Jhum cultivation. This farming system is believed to have originated in the Neolithic period around 7000 B.C. This is the most primitive form of agriculture and is still common amongst the tribal people in various pockets. Shifting cultivation is mainly confined to medium to high rainfall zones between 100 meters and 2,000 meters above sea level. It is practised in three types of vegetation, such as forests, bush and grasslands.

Introduction

Nature provides a wealth of genetic variation in both wild and cultivated plants. In the advanced selections conducted in developing superior crop varieties cultivated today agriculture represent only a small portion of the available gene pool. However wild species remain a reservoir of valuable genetic variation and represents a valuable source for exploitation of unexplored genetic variation for improvement of various agronomic traits. Most success has come from introgression of specific single gene controlled traits largely for disease resistance (Tomleyson, 2000 and Sergio et al., 2000). The identification of genes and co-adapted gene complexes that control complex agronomic traits such as adaptation to specific environmental stresses, crop quality, yield, plant architecture, flowering time (especially important for vegetable crops) has been less effectively addressed so far and remains a major and immediate challenge. Also, existence of low genetic diversity in breeding lines of many species used in various plant breeding programs is often resulting in development of insignificant improvement of the trait under investigation (Christopher, 2000). Understanding the spectrum, frequency and distribution of allelic variation in genes controlling such multiple genes controlled complex traits will improve our knowledge of exploitation of natural variation and promotes effective management and exploitation of functional biodiversity. In India efforts have been initiated in the exploitation, conservation of crop germplasm and technologies that are needed to fully exploit this natural diversity available in our major crop plants and their wild relatives. For example, centers that maintain diverse germplasm collections (both by ICAR and State Agricultural Universities nation wild are well established.

Different crops are grown in a field. Any plant growing in a place where it is not desired competing with the main crops, has to be weeded out and such plants are called ‘weed’.

Effect of weed menace The weeds

Reduce crop yield and production efficiency. It competes with the main economical crop for space, water and nutrients.

Reduce crop quality.

Hamper intercultural operations.

Reduce crop quality.

Obstruct the flow of water in the irrigation channels.

Exert allelopathic effect on crops.

Harbour insect and pests, which affect the main crop of interest.

Increase the cost of production.