eChapters

Soil aggregates refer to a group of two or more primary particles which cohere to each other more strongly than to surrounding particles. Under field conditions, these units also cohere to some degree with neighboring aggregates and form larger aggregates. The aggregates form and break easily into smaller aggregates during tillage and by disruptive action of water and air. The aggregates maintaining their identity are those in which the cohesive forces among particles are greater than the disruptive forces. A quantitative characterization of aggregates is being done by determining aggregate stability and size distribution of aggregates. The aggregate stability refers to the resistance of soil aggregates to breakdown by water, air, and mechanical manipulations. Numerous methods have been proposed to determine size distribution and stability of soil aggregates (Kemper and Rosenau, 1986). The size distribution of wet and dry aggregates determines overall tilth, size of pores and susceptibility of aggregates to movement by water and wind.

The variable amount of moisture contained in a unit mass or volume of soil and is the key factor affecting the growth of plants. Numerous other soil properties depend very strongly upon moisture content. Gravimetric (direct) and sensor based (indirect) methods are generally employed for soil moisture determination.

9.1 Gravimetric Method (Direct)

Principle

The gravimetric method is based on the principle that the water in the porous material is lost by evaporation on heating and the porous material undergoes an equivalent loss in its weight. However, the water loss may be limited by the internal operation within the complex porous material such as soil. This method is simple, routine, reliable, inexpensive, and easy to use. The major limitations of this method are that it is destructive, laborious and time consuming.

Soil consistency refers to the resistance offered by soil against forces that tend to deform it. The soil consistency varies with texture, kind of clay and moisture content. The efficiency of agricultural implements, animals and labour is largely affected by soil consistency as it directly inf luences the workability of a soil. Operations at suboptimal or supraoptimal water contents lead to clod formation, compaction, poor drainage and aeration. The common terms suggested by Atterberg (1912) to describe consistency are liquid limit, plastic limit, plasticity index, and sticky point. The physical basis of consistency limits is related to the interaction of water with soil. The water content at which plasticity is exhibited is the plastic limit or lower plastic limit of soil.

10.1 Liquid limit

Principle

The liquid limit refers to the water content at which resistance to f low becomes negligible and soil represents a semi f luid. A trapezoidal groove of specified shape cut soil held in a special cup will close in 25 taps on a hard rubber plate. The soil in the cup is 1.0 cm deep and the groove is 2.0 mm wide at the bottom with slopes outward at a 60^° angle horizontally. The soil in the walls of the groove f lows under the impact of the cup on the hard base and close the groove.

Climbers can be used to break the bareness of long walls, soften posts, frame doors and windows and beautify window boxes. With a fence or trellis, they can be used for screens, making a background for flower garden or quickly turning an ordinary porch or patio into a private, shady living centre. Some slower growing climbers are useful as container plants for patios. On the down side, most vine species have the potential to become invasive, spreading to areas where they may not be desirable or becoming too large for the intended area.

Types

Climbers are characterized as three types based on how they cling to a support. The kind of support needed depends on whether the Climbers cling by twining stems, orby specialized structures such as tendrils, adhesive disks and aerial roots. Climbers with twining stems wind around a support as they grow (Fig. 5.2). Examples of plant with twining stem sinclude bitter sweet, wisteria and trumpet creeper.Tendrils resemble thread like stems that wrap around any structure they contact (Fig. 5.1). Examples of plants with tendrils include grape, pea, and cucumbers. Some Climbers have specialized structures for clinging to a support with a disk-like suction cup (Fig. 5.3). Examples include Boston ivy and Virginia creeper. Other Climbers cling by means of small, aerial roots that attach to rough surfaces such as mortar, wood, and tree trunks (Fig. 5.4). Examples include English ivy, trumpet creeper and winter creeper euonymus.

Soil testing involves an estimation of its available nutrient status i.e. the portion or amount of nutrient directly available in soil for subsequent uptake by crop plant. This exercise is commonly referred to as soil testing and is used to arrive at optimum fertilizer application ratio. The need for estimation of available nutrient arises because only a small fraction of what the soil contains is the total nutrient content of the soil. Soil test are calibrated by correlating them with crop response and the result from the basis for making fertilizer recommendations.

Estimation of nutrient contents and forms in materials that are involved in nutrient supply and dynamics is a conical step towards planning scientific nutrient management. In this content, both soil and plant testing information comes out of the interpretation of analysis assumes a greater value when their concentrations and amounts can relate to soil fertility, nutrient availability, plant growth, yield and quality of the crop produce.

The term available phosphorus (P) refers to the inorganic form, occurring in soil solution, which is almost exclusively ‘orthophosphate’. The available P is considered to be a fairly good indicator/measure of the P supplying capacity of a soil. A knowledge of available P content of soils is important for determining its critical limit , based on soil-test-crop response calibration study.

Principle

In soil, phosphorus exists in the form of various types of orthophosphates. A very small fraction of these is available to plants at a given time. Available phosphorus content of soil consists mainly of Ca-P, Al-P and Fe-P. In the neutral and alkaline soils particularly, Ca-P is the dominant fraction. Organic –P fraction is also considerable amount, but is usually not include in the determination of available phosphorus. A large number of extractions, buffer solutions, acids and chelating agents have been suggested for available phosphorus from time to time. However, no single extractant appears to be suitable for all types of soils. Two types of extraction methods are more popularly adopted. Under acidic soil conditions, Bray No.1, which involves soil extraction with a solution consisting of 0.003 N NH₄F and 0.025 N HCl is widely followed. The fluoride complexes Al and Fe in soil, thus releasing some bound p besides the easily acid soluble P (largely Ca-P). This extraction is suitable for soils containing less than 2% calcite or dolomite because in calcareous soils, carbonates quickly neutralize the acid, resulting in less extraction of P.

All atoms can absorb light at certain discrete wavelengths corresponding to the energy requirement of the particular atom. When at ground state the atom absorbs light it is transformed into the excited state. It is the same atom containing more energy. This energy is measured in relation to the ground state and a particular excited state say for example in case of Na may be 2.2 eV (electron volts) above the ground state.

Each transition between different electronic energy states is characterized by a different energy and by a different wavelength. These wavelengths are sharply defined and when a range of wavelengths is surveyed, each wavelength shows as a sharp energy maximum (a spectronic line). These characteristic lines distinguish atomic spectra. The lines, which originate in the ground state of atom, are most often of interest in atomic absorption spectroscopy. These are called the resonance lines. The atomic spectrum, characteristic of each element, then comprises a number of discrete lines, some of which are resonance lines. Most of the other lines arise from excited states rather than the ground state. The lines of excited states are not useful generally in atomic absorption analysis as most of the atoms in a practical atomizer are found in the ground state.

Introduction

The objective of soil sampling is to obtain reliable information about a particular soil. The value of laboratory data in soil studies largely depends on effective sampling. Soil sampling is one of the most important aspects in the determination of the properties of the soil. Care in preparation and analysis can overcome the damages of careless or inappropriate sampling in the field (Bates, 1993). Errors arising from sampling are mainly related to spatial variability of the soil. While keeping in mind financial constraints, sampling procedures should be adopted properly to minimize the influence of spatial variability and to maximize the accuracy of mean plot values for the measured soil variables. The obtained soil data should be representative for the whole observation plot, taking into consideration the spatial variability of the soil within the plot.

Importance of soil sampling

Soil sampling and testing are done to provide an estimate of the capacity of the soil to supply adequate amount of nutrients to meet the needs of growing crops and information to its nature and problem. Traditionally, the goal of soil sampling is to develop a representative estimate of a field. A few grams of soil are actually used for the laboratory analysis. That small amount must represent the entire area for which the recommendation is to be made. The samples should be collected in such a way that it would represent the area for which recommendation is to be made.

Three types of water movement within the soil are recognized. They are

1. Saturated flow
2. Unsaturated flow
3. Water vapour movement

Saturated flow

This occurs when the soil pores are completely filled with water. This water moves at water potentials larger than 33 kPa. Saturated flow is water flow caused by gravity’s pull. It begins with infiltration, which is water movement into soil when rain or irrigation water is on the soil surface. When the soil profile is wetted, the movement of more water flowing through the wetted soil is termed percolation.

Hydraulic conductivity can be expressed mathematically as

Measurement of soil aeration

Oxygen Diffusion Rate (ODR) - the rate at which O₂ in soil air is replenished. ODR decreases with soil depth.

Measurement of ODR in soil

Lemon and Erickson (1952) devised a method for measuring oxygen diffusion in the soil system with the help of platinum micro electrode

Principle

When a certain potential is applied across the platinum electrode and a reference electrode inserted in the soil, oxygen is reduced at the platinum surface. The electric current flowing between two electrodes is proportional to the rate of oxygen reduction. The later, in turn, is related to the rate of oxygen diffusion to the electrode. The oxygen diffusion rate (ODR) is calculated from the measured electric current with the following equation.

Microorganisms being minute and microscopic are ubiquitous. Besides supporting the growth of various biological systems, soil and soil microbes serve as a best medium for plant growth. Soil fauna & flora convert complex organic nutrients into simpler inorganic forms which are readily absorbed by plants.

Soil microbes as nitogen fixers-Symbiotic (Associative): The organisms involved are Rhizobium, Bradyrhizobium in legumes(aerobic): Azospirillum, Azotobacter (grasses), Actinonycetes- Frantkia (with Casuarinas, Alder).

Soil microbes as biocontrol agents: Several ecofriendly bioformulations of microbial origin are used in agriculture for the effective management of plant diseases, insect pests, weeds etc. eg: Trichoderma sp and Gleocladium sp are used for biological control of seed and soil borne diseases. Fungal genera Entomophthora, Beauveria, Metarrhizium and protozoa- Maltesia grandis. Malameba locustiae etc.- are used in the management of insect pests. Nuclear polyhydrosis virus (NPV) is used for the control of Heliothis/American boll worm. Bacteria like Bacillus thuringiensis, Pseudomonas are used in cotton against Angular leaf spot and bollworms.

Degradation of pesticides in soil: Soil receives different toxic chemicals in various forms and causes adverse effects on beneficial soil micro flora / micro fauna, plants, animals and human beings. Various microbes present in soil act as the scavengers of these harmful chemicals in soil. The pesticides/chemicals reaching the soil are acted upon by several physical, chemical and biological forces exerted by microbes in the soil and they are degraded into non-toxic substances and thereby minimize the damage caused by the pesticides to the ecosystem. For example, bacterial genera like Pseudomonas, Clostridium, Bacillus, Thiobacillus, Achromobacter etc. and fungal genera like Trichoderma, Penicillium, Aspergillus, Rhizopus, and Fusarium play important role in the degradation of the toxic chemicals / pesticides in soil.

Biodegradation of hydrocarbons: Natural hydrocarbons in soil like waxes, paraffins, oils etc are degraded by fungi, bacteria and actinomycetes. E.g. ethane (C2 H6) is metabolized and degraded by Mycobacteria, Nocardia, Streptomyces Pseudomonas, Flavobacterium and several fungi.

The crop growth and productivity is conditioned by many factors of which, the nutrient status (Content) of plant parts such as leaf, stem, etc play a critical role. Moreover the leaf and stem are considered as the indicator parts of plants for assessing the nutrients content of plant. Each crop plant requires the essential element at a specific concentration at different growth stages and it is known as ‘critical level’. When the nutrient content of plant depletes below the critical level the plants may exhibit some symptoms. The requirement or otherwise the availability of nutrients can be assessed by i) plant diagnosis ii) soil analysis and iii) plant analysis by two methods a) by qualitative test and b) by quantitative estimation. Based on the plant or soil tests, the required nutrients can be applied for crops to sustain the growth and rectify the deficiency disorders. The rapid tissue test would pave way for rectifying the nutritional problems for quick recovery, however the quantitative estimation of both plant and soil for nutrients concentration will be more useful and economic for applying fertilizers either as basal or foliar and would be the long term strategy to cope up with nutritional problems.

For rapid tissue test to assess the nutrient status, different parts of plant should be taken as indicator tissue and some of the representative crops are furnished below:

Introduction

In classification of irrigation water, it is assumed that the water will be used for average conditions with respect to soil texture, infiltration rate, drainage, quantity of water used, climate and salt tolerance of the crop. Large deviations from the average for one or more of these variables may make it unsafe to use what, under average conditions, would be a good water; or may make it safe to use what, under average conditions, would be a water of doubtful quality. The relationship to average conditions must be kept in mind in connection with the use of any general method for the classification of irrigation water.

However, the quality of irrigation water is evaluated, mainly by the quantity of dissolved salts, proportion of anions, monovalent and divalent cations, sodium adsorption ratio, residual sodium carbonate, potential salinity, specific ion toxicity, proportion of magnesium, calcium in water etc.

Cation exchange: The ‘soil cations’ essential for plant growth include ammonium, calcium, magnesium, and potassium. There are three additional ‘soil cations,’ which are not essential plant elements but affect soil pH. The additional ‘soil cations’ include sodium, aluminum and hydrogen.

The major distinguishing characteristic of cations is their positive charge. Just like a magnet, a positive charge is strongly attracted to a negative charge. When soil particles have a negative charge, the particles attract and retain cations. These soils are said the have a cation exchange capacity. Although most soils are negatively charged and attract cations.

The ‘soil cations’ are further divided into two categories. Ammonium, calcium, magnesium, potassium, and sodium are known as the ‘base cations,’ while aluminum and hydrogen are known ‘acid cations.’ Unlike the other base cations, sodium is not an essential element for all plants. Soils that contain high levels of sodium can develop salinity and sodicity problems.

The words ‘base’ and ‘acid’ refer to the particular cation’s influence on soil pH. As you might suspect, a soil with a lot of acid cations held by soil particles will have a low pH. In contrast, a highly alkaline soil predominately consists of base cations.

Cations in the soil compete with one another for a spot on the cation exchange capacity (Table 42 and Fig 18). However, some cations are attracted and held more strongly than other cations. In decreasing holding strength, the order with which cations are held by the soil particles follows: aluminum, hydrogen, calcium, potassium and nitrate, and sodium.

Windows is an operating system with a Graphical User Interface (GUI). GUI displays graphical objects called icons, which represents the items you use. Also it is a menu driven interface, where you have menus and submenus to perform even the most basic tasks such as File open, Copy, and Help etc. The user need not know the computer commands, he just need to know simple English language to operate windows. This feature of windows made it a widely accepted operating system. Also windows allow multiprocessing environment, where we can perform more than one task simultaneously. For example, if you need to take a print out of a very long report which may take a couple of hours, you may give the command, and leave it at the background, and then you can keep working on the other applications. Windows supports a very useful pointing device called a mouse. With the mouse you can go anywhere on the screen and click where ever you want and pass instructions.

MS-ACCESS is a very powerful RDBMS (Data Base Management System) which manages data in term of special table called relation. Using MS-ACCESS you can manage all your information from a single database file. Database files are stored with extension. MDB.

ACCESS stores information in the form of tables and you build your database on its basis. Each row in a table holds all information’s & for a particular person it is called a record. And each column contains different pieces of information regarding that person, like Roll No, Name, Class, Address etc. Same as MSACCESS involves.

In ACCESS, you have few things known as Forms, Reports and Queries. They allow you to check and get desired information as and when required.

12.1 Meaning and Definition

A flow chart is a graphical or symbolic representation of a process. Each step in the process is represented by a different symbol and contains a short description of the process step. The flow chart symbols are linked together with arrows showing the process flow direction. This diagrammatic representation can give a step-by-step solution to a given problem. Flowcharts are used in analyzing, designing, documenting or managing a process or program in various fields.

Commonly used terms in swine husbandary

Angier, Natalie (2009-11-09). “Pigs Prove to Be Smart, if Not Vain”. The New York Times (New York, New York, US: The New York Times Company).

Anonymous 2002-03. Annual Report of Animal Husbandry and Veterinary Department, Directorate of Animal. Husbandry and Veterinary Department, Government of Mizoram, Pp 8

Broom, Donald M.; Hilana Sena, Kiera L. Moynihan (2009-11). “Pigs learn what a mirror image represents and use it to obtain information”. Animal Behaviour 78 (5): 1037-1041.

Burkholder JoAnn; Bob Libra, Peter Weyer, Susan Heathcote, Dana Kolpin, Peter S. Thorne, Michael Wichman (2007) Impacts of Waste from Concentrated Animal Feeding Operations on Water Quality. Environ Health Perspectives. 115:308-312.

Chandrashekhar Sahukar. (2000). Piggery India Year Book, pp. 343-347.

Christianson, L.L, Bane D.P, Curtis S.E, Hall W.F, Muehling A.J, and Riskowski G.L. 1989. Swine Care Handbook for Pork Producers Using Environmentally Controlled Housing. Des Moines: National Pork Producers Council.

Crucik Shank, R et al (1965). Medical Microbiology, ELBS, London.

Curtis, S.E., et al. 1988. Guide for the Care and Use of Agricultural Animals in Agricultural Research and Teaching. Champaign III, Consortium for Developing a Guide for the Care and Use of Agricultural Animals in Agricultural Research and Teaching.

Dalton, C. and. Kilgour R.1984. Livestock Behaviour; A Practical Guide. Granada Publishing, Lt., Frogmore, St. albans, Herts, U.K.

Daszak et al (2000). Emerging Infectious Diseases of Wildlife — Threats to Biodiversity and Human Health. Science Vol 287 pp 443-449

Delgado, C., Rosegrant, M., Steinfeld, H., Ehui, S., Courbois, C., 1999. Livestock to 2020. The next food revolution. Food, Agriculture, and the Environment Discussion Paper28. IFPRI, FAO, ILRI

DeShazer, J.A and ONil erhults D.G.1982. Energy Demand in Livestock Production. Livestock Environment, Proceedings of 2nd International Livestock Environment Symposium. American Society of Agricultural Engineers, St. Joseph, MO.

Donham K. (1998). “The impact of industrial swine production on human health”. In Thu K, Durrenberger E. Pigs, Profits, and Rural Communities. Albany, NY: State University of New York Press. pp. 73-83.

Eastman, Wilbur F. The Canning, Freezing, Curing & Smoking of Meat, Fish & Game, Garden Way Publishing, 1975, ISBN 0-88266-045-4

Embog, H.D. et at (1996). How the Danish surveillance system for Salmonella has influenced the microbiological quality of swine carcase meat. Proc. Int. Pig. Vet. Soc.14:714.

FAO (1983). Integrated crops and livestock in West Africa. Animal Production and Health paper. Rome, No. 41. Foodand Agriculture Organisation of the United Nation.

FAO (1998a). Farm Animal Genetic Resources: Biodiversity for food and agriculture. Food and Agriculture Organisation of the United Nation.

FAO (1998b). Local animal breeds still threatened by extinction, No. 4. Food and Agriculture Organisation of the United Nation.

FAO (2001). Bulletin of Statistics. Vol.2, No.1. Food and Agriculture Organisation of the United Nations.

Cervical vertebrae

The skeleton of neck (Fig 2-1) is formed by the cervical vertebrae. These are seven in number. Of these, the first and second cervical vertebrae are highly modified and deviate greatly from the general architectural plan of the vertebrae. The third, fourth and fifth cervical vertebrae are similar and confirm the general plan of the vertebrae. The sixth and seventh vertebrae have some special characteristics but do not deviate much from the general plan. The general plan of vertebrae and the vertebral column has been described in the chapter on skeletal system under Part I on systemic anatomy. Hence, only regional specific characters of the cervical vertebrae are described hereunder.

First cervical vertebra (Atlas)

The first cervical vertebra (Figure 2-2 A) is called the atlas vertebra because in man it supports the globe of the head. This is an atypical vertebra and it deviates greatly from the general plan of vertebrae. The body and the spinous process are absent. The arch forms a bony ring from which two large curved plates, the wings project laterally. The ring encloses the vertebral foramen. It forms a part of the vertebral canal through which passes the spinal cord.

Spinal nerves

The thoracic spinal nerves are thirteen pairs in ox. These are named and numbered according to the vertebra caudal to which they emerge from the vertebral canal. They emerge from the vertebral canal through the respective lateral vertebral (intervertebral) foramina. Each nerve, after its emergence, divides into dorsal and ventral branches. Each dorsal branch passes up dorsally between the transverse processes of the vertebrae and divides in to medial and lateral branches. The medial branch passes upward and supplies the dorsal muscles of the back. The lateral branch passes laterally on the deep surface of the longissimus dorsi muscle. At the lateral border of this muscle it passes between this and longissimus costarum muscles and becomes a cutaneous nerve which divides into ascending and descending branches supplying the muscles and the skin of this region.. Before its division, the lateral branch supplies muscular branches to the longissimus dorsi and longissimus costarum muscles.

The ventral branches continue ventrally as intercostal nerves. The first and second thoracic nerves, before their continuation as intercostal nerves, give out a branch to the brachial plexus. At a short distance from the spinal nerve, the ventral branch of each of these nerves is connected to sympathetic trunk by a ramus communicans containing preganglionic and postganglionic sympathetic fibres. The intercostal nerves run down ventrally through the intercostal spaces, lying between the external and internal intercostal muscles close to the caudal border of the respective rib and in company with the intercostal vessels. Along this course they supply these muscles. After a variable distance, the intercostal nerves and vessels traverse through the internal intercostal muscles and become subpleural in position. The second to eighth nerves end in the transversus thoracis muscle. The rests behind these end in the rectus abdominis and other abdominal muscles and the skin in this region.

The urinary organs include the kidneys, ureters, bladder and urethra (Fig. 4-5 A).

Kidneys

The kidneys are two compound tubular glands situated retroperitoneally in the sublumbar region. They are elongated, the right kidney being elliptical in outline and the left one slightly oval. They are red brown in colour. The weight of each kidney varies from 500 to 700 gm, the left kidney being about 25 gm heavier than the right kidney. The outer surface of the bovine kidneys is marked by polygonal lobes which are about twenty in number and are separated from each other by deep grooves (fissures). The grooves are filled in by fat. Both the kidneys are embedded in a large amount of perirenal fat termed as adipose capsule.

Horse

The ovaries in mare are bean shaped and much larger than those of cow. Each is about 7 to 8 cm long and about 3 to 4 cm thick. It weighs about 70 to 80 gm. These are situated in the sublumbar region under the fourth or fifth lumbar vertebra. They are usually in contact with the roof of the abdomen. The average distance of ovaries from the vulvar orifice is about 50 to 55 cm in the average sized mare. The notch on the free border leads to a depression, the ovulation fossa where ovulation occurs.

The uterine tubes are shorter and more flexuous in mare than those in cow. Each is about 20 to 30 cm long. At its ovarian end it is wider with a diameter of about 4 to 8 mm and becomes narrower at its uterine end with a diameter of about 2 to 3 mm.

The uterus in mare is situated partly in abdomen and partly in pelvis. The horns of the uterus are usually pressed against the sublumbar muscles by the intestine. When moderately distended they are about 25 cm long. The junction of the uterine horns with the body of the uterus is abrupt. The average length of the body is about 18 to 20 cm and its diameter is about 10 cm when moderately distended. The cervix is about 5.0 to 7.5 cm in length and 3.5 to 4.0 cm in diameter. The cervical canal is straight. The mucous membrane of the uterus has no cotyledons.

The vagina in mare is shorter than that in cow. It measures about 15 to 20 cm in length and 10 to 12 cm in diameter when slightly distended. Most of the vagina is retroperitoneal.

Horse

The visceral branches of the abdominal aorta are the coeliac, cranial mesenteric, renal, caudal mesenteric and testicular or ovarian.

The coeliac artery in horse is shorter than that in ox. It arises from ventral surface of the aorta and reaches the dorsal surface of the pancreas where it divides into three branches, the left gastric, hepatic and splenic.

The left gastric artery passes ventrally and cranially in the gastrophrenic ligament, gives off pancreatic and oesophageal branches and divides dorsal and caudal to the cardia into parietal and visceral branches. The parietal branch crosses the lesser curvature of the stomach just to the right of the cardia and ramifies on its parietal surface. The visceral branch is distributed in the similar manner on the visceral surface of the stomach. A long but narrow oesophageal branch arises from the parietal branch of the left gastric, passes cranially through the hiatus oesophageus and enters the thoracic cavity dorsal to the oesophagus and anastomoses with the oesophageal branch of broncho-oesophageal artery.

The hepatic artery is larger than the left gastric. It passes dorsal to the pancreas and reaches medial to the portal vein, divides into right and left branches from which the terminal branches enter the liver through portal fissure. Its collateral branches are the pancreatic, right gastric and the gastroduodenal arteries. The gastroduodenal artery further divides into right gastroepiploic and the cranial pancreaticoduodenal arteries.

Subclavian artery

The fore limb is chiefly supplied by the subclavian artery (Fig. 5-4 A). It originates from the brachiocephalic trunk within the thoracic cavity. The left subclavian detaches from the brachiocephalic trunk opposite the second rib, passes craniodorsally towards the thoracic inlet winds around the cranial border of the first rib and then courses caudoventrally through the axillary space between the subscapular and teres major muscles as the axillary artery. It gives off the subscapular branch and continues as the brachial artery. The right subclavian is the direct continuation of the brachiocephalic trunk after the later gives off the bicarotid trunk opposite the first rib. It gets exit through the thoracic inlet, winds around the cranial border of the first rib and then continues as the right axillary artery and thereafter as the brachial artery similar to the artery of the left side.

Horse

The arteries of fore limb of horse are more or less similar in their course and distribution. However, there are some special features in respect of some of these arteries as described below.

The brachial artery descends vertically on the medial aspect of humerus to its distal extremity, crosses it obliquely and descends along the joint capsule and medial lateral ligament of elbow joint, gives off common interosseous artery at the proximal third of the forearm and then continues distally as median artery.

The median artery descends along the caudomedial aspect of the radius covered by flexor carpi radialis muscle and divides just proximal to medial condyle into radial and collateral ulnar (ulnar) arteries.

The collateral ulnar artery is smaller of the two terminal branches of median artery. It descends along the cranial surface of radius under cover of the extensor carpi radialis and terminates a little above the carpus by anastomosing with a branch of radial artery.

Horse

The femur of horse is more massive than that in ox. The proximal third of the caudal surface of shaft of femur presents a rough eminence for attachment of biceps femoris muscle. The trochanter minor is a rough ridge like structure. The proximal third of the lateral border of shaft presents trochanter tertius for attachment of superficial gluteus muscle. The trochanter major is comprised of a convexity, a summit and a crest. The trochanteric ridge is vertical and it connects the trochanter major with the third trochanter. The lateral supracondyloid crest and the supracondyloid fossa are better developed in horse than that in ox. The patella of horse is wider and longer than that of ox.

The tibia in horse is relatively longer than that in ox. The popliteal line is prominent. It extends from the proximal third of the medial border, obliquely crosses the caudal surface and ends at the middle of the lateral border of the shaft of tibia. The medial border in its proximal third bears a small popliteal tubercle for attachment of popliteus muscle. The lateral border is attached to the shaft of the fibula and encloses an interosseous tibiofibular arch with the fibula. At the proximal extremity, the cranial tuberosity is vertically grooved. The lateral condyle on its lateral side presents facet for articulation with the proximal extremity of fibula. At the distal extremity, the grooves are oblique. The lateral malleolus is fused with the distal extremity of tibia, The medial malleolus is more prominent than the lateral one.

Horse

The arteries of the hind limb of horse have in general similar architecture as that of ox except the special features mentioned below.

The deep circumflex iliac artery which is a branch of the external iliac artery in ox has a variable origin in horse. It may originate directly from the aorta or the common iliac trunk just prior to the origin of the external iliac artery. The prepubic and deep femoral arteries arise either by a common trunk or separately from the femoral artery. The obturator artery is a well developed independent branch of the femoral artery in horse as against its origin as a branch of deep femoral artery in ox. The saphenous artery is a small branch of femoral artery and it supplies the skin on the medial aspect of the thigh and leg. The popliteal artery terminates by its division into cranial and caudal tibial arteries at a lower level in horse than that in ox. The caudal tibial artery is larger and longer in horse than that in ox. From the proximal plantar arch extend four caudal metatarsal arteries instead of four, two of them are superficial and the other two deep branches. The large metatarsal artery descends along the groove between the large and lateral small metatarsal bone and divides just above the fetlock into lateral and medial digital arteries. Each digital artery divides at the middle of the wing of the third phalanx into preplantar and plantar digital arteries. The preplantar digital arteries supply the sensitive laminae of the sole. The plantar digital arteries of the opposite sides form anastomosis. Small laminar branches from the anastomosis form the circumflex artery of the toe which supplies branches to the sole.

Pelvic (Lumbosacral) plexus

The hind limb is supplied by the nerve branches extending from the Pelvic (lumbosacral) plexus (Fig. 6-4 A and B) which is formed by the convergence of the ventral divisions of the last three lumbar and first two sacral nerves. It is formed in two parts, the cranial and caudal. The two parts are connected by anastomotic branches. The cranial (lumbar) part is formed by the fourth and fifth lumbar nerves and lies between the psoas major and psoas minor muscles while the caudal (sacral) part is formed by the sixth lumbar and first and second sacral nerves. Some times a root from third sacral also joins this part. It lies on the pelvic surface of the sacrosciatic (ischial) ligament. The nerves extending from the cranial part of the plexus are the lateral cutaneous femoral, the femoral and the obturator. The nerves extending from the caudal part are the cranial gluteal, caudal gluteal and the sciatic (ischiatic).

Lateral cutaneous femoral nerve

The lateral cutaneous femoral nerve while leaving the cranial part of the plexus, receives fibres from the fourth lumbar nerve, passes caudally between the psoas major and psoas minor muscles and reaches the tuber coxae. Here it perforates the obliquus abdominis externus muscle in company with the circumflex iliac artery and reaches the skin of the lateral aspect of the thigh. In this course, the nerve supplies the psoas major, psoas minor, iliacus and external oblique muscles of the abdomen and the skin and cutaneous muscle on the lateral face of the thigh.

In the past several insect pests had entered India and are causing economically perceptible damage to native crops. The Government of India, in line with the International Standards on Phytosanitary Measures (ISPM), notified ‘Plant Quarantine Order, 2003’ to reduce the risk of introduction of exotic insect pests in India. The storage insect pests of quarantine concern for India have been listed in Table 9.1.

Plant parasitic nematodes favour the establishment of secondary pathogens viz., fungi, bacteria, virus etc. The nematodes alter the host in such a way that the host tissue becomes suitable for colonization by the secondary pathogens. Even though the nematodes themselves are capable of causing considerable damage to the crops, their association with other organisms aggravate the disease. The nematodes cause mechanical wound which favours the entry of microorganisms. In some cases, the association of nematode and pathogen breaks the disease resistance in resistant cultivators of crop plants.

Nematode - Fungus Interaction

Nematode - fungus interaction was first observed by Atkinson (1892) in cotton. Fusarium wilt was more severe in the presence of Meloidogyne spp. Since then the nematode - fungus interations had received considerable attention on important crops like banana, cotton, cowpea, brinjal, tobacco and tomato. Some examples of nematode - fungus interaction are given in the following table.

Crossandra

Crossandra (Crossandra undulaefolia) is one of the important commercially grown flower crop in Tamil Nadu. In recent years there is a marked decline in the cultivation of this crop in Madurai, Dindigul, Coimbatore, Salem, Thiruvannamalai and Tiruchirappalli districts. The common problem with the crop is death of plants in patches during the second and third year. This is due to the nematode-fungal complex disease in the crop.

Investigations revealed the association of root-knot nematode, Meloidogyne spp. and the root-lesion nematode, Pratylenchus delattrei with the crop along with fungal patheogen, Fusarium solani.

Root-knot nematode

Both M. incognita and M. javanica are reported to cause damage and yield loss to the crop. The affected plants exhibit stunted growth, yellowing of leaves and also have chlorotic symptoms. The nematode in association with R. solani causes serious damage to the crop. The infested plants show root galls.

Nematode associated with insects are referred as entomophilic, entomogenous and entomophagous nematodes. Generally they belong to the superfamilies Tylenchoidea, Rhadbitoidea, Oxyuroidea and Mermithoidea of the phylum Nematoda.

Nature of parasitism

Christie (1914) divided the nematodes associated with invertebrates into three groups.

• Those nematodes which live in the alimentary tract of he invertebrates.
• Those nematodes which are more or less closely related to free living species and often have a combination of saprophagous and parasitic habits.
• Those nematodes which parasitizes the body cavity or tissue of their host.

Entomophilic nematodes are group of parasites that cause debilitation, sterility or death of insects. Entomophilic nematodes vary greatly in size and shape having the insects as intermediate or as definite hosts. Many group of insects are parasitised by nematodes.

Objectives

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

Introduction

A compound microscope is an optical instrument consisting of two short focal-length convex lenses that are used to observe the highly magnified images of small objects by naked eyes. The compound microscope is capable of magnifying up to 1000 the image of a small object by complex system of lens arrangement. The working distance varies from 0.14 to 4 mm. Compound microscopes generally require the sample to be seen to be sufficiently thin, or translucent, to allow the light to pass. Such microscopes provide high magnification, but the view is two-dimensional.

In 1868, Johann Friedrich Miescher, a young Swish medical student got excited with an acidic substance that he isolated from pus cells obtained from bandages used to dress human wounds. To obtain large quantities of pus for his experiment, Miescher began purchasing used bandages from surgical clinics in Tuebingen, Germany. He separated pus cells from bandages and treated the cells with pepsin, a proteolytic enzyme that he isolated from stomach of pigs. After pepsin treatment, he recovered an acidic substance that was named as “nuclein” by him. This nuclein was unusual in the sense that it was rich in nitrogen and phosphorous, two elements known at that time to coexist only in certain types of fat. Miescher’s paper on this investigation was published in 1871. At that time, importance of Miescher’s nuclein was not fully appreciated. Even the existence of polynucleotide chains, the key component of the acidic material in Miescher’s nuclein was not documented until 1940s. The role of nucleic acid in storing and transmitting genetic information remained un-established until 1944 and the double-helix structure of DNA was not discovered until 1953 by James Watson and Francis Crick. Even in 1953, many geneticists remained skeptical to accept the role of nucleic acid as the genetic information carrier rather than proteins as nucleic acids exhibited less structural variability than the proteins (Snustad et al., 1997).

Regulator Genes

Bacterial cells are capable of producing many kinds of enzymes in relatively large quantities but the kinds and amount of enzymes actually produced at any given time are usually those which are required at that particular time in response to the prevailing environment. Inducible enzymes are ordinarily absent or present in very small quantities until a specific compound appears. This compound is called as inducer. A typical example of this is production of b galactosidase (an enzyme that splits lactose into galactose and glucose, Fig. 44.1) once the lactose is introduced into the medium on which E. coli cells are grown. Here lactose acts as inducer for the enzyme b galactosidase.

Abstract

Fusarium wilt is major disease in Central India, the major lentil growing region of country. The disease is soil borne causing heavy loss, development of wilt resistant varieties is most effective means of controlling this disease. Highly resistant sources of wilt in lentil have not been reported from the Indian lentil breeding programme. One hundred thirty lentil genotypes including one susceptible check were evaluated in control conditions of green house against wilt, based on controlled condition screening- LL 1370, IPL 333, PL4, RLG 195, RVL 14-4, L 4737, RKL 607-1, WBL 77, LL 1320, LL 1397, VL 525, LL1379, VL526, RVL14-5, L4717, VL126, L4076, RLG191 and VL150 have been identified as highly resistant genotypes. These can be used in hybridization programme for wilt resistance breeding and studying the inheritance of wilt resistance in lentil.

Abstract

The major losses of banana at present by Panama wilt disease pathogen of banana and its management is very typical because it is caused by a soil-borne pathogen (Fusarium oxysporum f.sp. c u b e n s e ). The micronutrients are used to manage the disease as well as it provides the healthiness of plant and increases the fertility of the soil that’s why the plant is free from the disease or less infected. An experiment of micronutrients was conducted in the laboratory of plant pathology BAU, Sabour for Invitro evaluation of the micronutrients viz. Zinc Sulfate, Ferrous Sulfate, Ammonium Sulfate, Copper Sulfate, Calcium Nitrate, Borax and Potassium Chloride against Fusarium oxysporum f.sp. cubense causing Panama wilt of banana. The results of the experiment revealed that among the micronutrients used, Borax @ 500 and 750 ppm completely inhibited the mycelial growth of FOC followed by Zinc Sulfate (45.7, 42.6, 39.2 and 18.5 mm at 100, 250, 500 and 750 ppm respectively). The incorporation of borax in the solid medium at higher concentrations viz., 500 and 750 ppm is very effective for the management of Panama wilt disease of banana. This approach leads to maintain our ecosystem sustainability for a longer time and manage the disease.

Abstract

The agricultural scientists particularly those who are in advisory service, irrespective of specialization, are often approached by the farmers with diseased samples of their crops and sought advice on plant protection strategy. The strategy includes components of control measures, doses, mode and time of application. In the present article different steps of formulation of plant disease control strategy are discussed. To further elaborate the contents, examples from integrated management strategy of mango malformation disease is cited.

Keyword: Mango Malformation

Introduction

Mango malformation, disease was first time reported from Darbhanga District of Bihar State in 1891 by G. Watt. The disease is currently prevalent in almost all the mango growing country and is thus designated as the plant disease of International importance and previously considered to be a serious problem in the northern parts of the country, has now started to appear in central India too in severe form. It is well known, the mango malformation is the most serious disease, rendering mango cultivation non-lucrative in subcontinent and other regions of the world (Ahmad et al., 2002; Ploetz, 2001). Mango malformation caused by fungus Fusarium moniliforme var. Subglutinans, are proved (Freeman 1999; Zheng and Ploetz, 2002). Recently, these isolates were described as members of a new species, F. mangiferae Britz, Wingfield and Marasas sp nov. (Britz et al., 2002). The casual organism of mango malformation grows well at lower temperature and higher relative humidity. The disease is quite common in both grafted and the seedling plants (Kumar and Chakrabarti, 1997). The symptoms manifest as bunchy top (BT) in 4-5 month old seedlings in the nursery, vegetative malformation (VM) of twigs arising from axillary buds and malformation of inflorescence (MF). Normally floral malformation is more prevalent in bearing trees than vegetative malformation. Flowers in the malformed panicle are much enlarged and crowded with hypertrophied axes of the panicle. Malformed inflorescences/ panicle of different varieties were variable in respect of their shapes, sizes, growth and compactness, depending upon the cellular structure and physiology under environmental factors (Chakrabarti et al., 1990). Generally malformed inflorescences produce no fruit, or abort already stages (Schloser, 1971) and is directly responsible for reduction in yield (Kumar et al., 1993 and Singh et al., 1998). In the present study the incidence of Floral malformation on a large number of mango cultivars was recorded over a period of 5 years with a view to identify the entries of future resistant breeding programme.

Although it can be argued that due to its overall trendiness, they have been a lot of recent developments in making it more fun to work with. As a molecule, it is very similar to DNA (the most notable chemical difference is its flexibility), but suffers because the nucleases (RNases) that can destroy it are notoriously very stable and very difficult to get rid of.

Two types of molecular weight (MW) standards are routinely used. The Lambda/HindIII and PhiX174/HaeIII MW standards provide a useful reference for calculating molecular weights of large and small DNA fragments, respectively, after electrophoretic separation; the “internal MW standards” provide a means for normalizing fragment migration distances within each lane to facilitate comparisons between lanes on the same or different luminographs in fingerprinting studies.

Minisatellite is a section of DNA that consists of a short series of bases 10– 60bp. These occur at more than 1000 locations in the human genome. Some minisatellites contain a central (or “core”) sequence of letters “GGGCAGGANG” (where N can be any base) or more generally a strand bias with purines (Adenosine (A) and Guanine (G)) on one strand and pyrimidines (Cytosine (C) and Thymine (T)) on the other. It has been proposed that this sequence per se encourages chromosomes to swap DNA. In alternative models, it is the presence of a neighbouring cis-acting meiotic double-strand break hotspot which is the primary cause of minisatellite repeat copy number variations. Somatic changes are suggested to result from replication difficulties (which might include replication slippage, among other phenomena). When such events occur, mistakes are made, this causes minisatellites at over 1000 locations in a persons genome to have slightly different numbers of repeats, thereby making them unique. The most highly mutable minisatellite locus described so far is CEB1 (D2S90) described by Vergnaud.

Since the mid 1980s, genome identification and selection has progressed rapidly with the help of PCR technology. A large number of marker protocols that are rapid and require only small quantities of DNA have been developed. Three widely-used PCR-based markers are RAPDs (Williams et al., 1990), SSRs or microsatellites (Tautz, 1989), and AFLPs (Vos et al., 1995). Each marker technique has its own advantages and disadvantages. RAPD markers are very quick and easy to develop (because of the arbitrary sequence of the primers) but lack reproducibility (Karp et al., 1997; Hansen et al., 1998; Jones et al., 1999; Virk et al., 2000). AFLP has medium reproducibility but is labour intensive and has high operational and development costs (Karp et al., 1997). Microsatellites are specific and highly polymorphous (Karp et al., 1997, Jones et al., 1999), but they require knowledge of the genomic sequence to design specific primers and, thus, are limited primarily to economically important species.

The choice of a molecular marker technique depends on its reproducibility and simplicity. The best markers for genome mapping, marker assisted selection, phylogenic studies, and crop conservation have low cost and labour requirements and high reliability. Since 1994, a new molecular marker technique called inter simple sequence repeat (ISSR) has been available (Zietkiewicz et al., 1994). ISSRs are semiarbitrary markers amplified by PCR in the presence of one primer complementary to a target microsatellite. Amplification in the presence of nonanchored primers also has been called microsatellite-primed PCR, or MP-PCR, (Meyer et al., 1993).