eChapters

Bone healing can be modified by variety of endogenous or exogenous factors that affect the metabolic function of bone cells. The Food and Drug Administration is approved the use of low-intensity ultrasound for the accelerated healing of fresh fractures in October 1994 and for the treatment of established nonunion in February 2002. The first regulatory approval is based primarily upon two rigorous, double - blind, placebo controlled clinical trials, which shows that the rate of healing of fresh fracture is accelerated by treatment with ultrasound. Therapeutic ultrasound has been able to improve functional activity, reduce post-ambulatory period, alleviate suffering and restore the animal’s health early. It has been used frequently for acceleration of healing in various musculotendinous injuries in animal. However, the role of ultrasound therapy in different dose levels in fracture healing has not been elucidated properly. In view of the above fact, this chapter is undertaken to investigate the effects of therapeutic ultrasound in two different doses, on cortical bone healing in rabbits.

Twelve clinically healthy adult New Zealand white rabbits of either sex are divided equally into three groups A, B and C, and kept on standard diet and uniform management. In all animals, mid-shaft simple transverse fracture is created in both the ulnae under thiopental (2.5%) anaesthesia. All the animals are administered broad-spectrum antibiotic and analgesic and surgical wounds are dressed daily with povidone iodine and antibiotic cream for 4 days postoperatively. Group A animal is received pulsed ultrasound therapy @ lW/ cm² (1:1) whereas, group C animals is received continuous ultrasound therapy @ 3 W/cm², starting on day 4 after the creation of fracture. Ten treatments, each consisting of 5 min duration, are given on alternate days. Group B animals are served as control. In both the test groups (A and C), the transducer head of the ultrasound machine is moved in a linear fashion along the length of the bone after applying ultrasound gel.

Standard postoperative management of animals with fractures includes the use of nonsteriodal anti-inflammatory drug (NSAID). Nonsteriodal anti-inflammatory drug inhibits inflammatory responses by blocking prostaglandin (PG) synthesis via the Cyclooxygenase pathway of arachidonic acid metabolism. However, PG is important factor in early phase of bone healing. A local increase of PG concentration is a response of bone to trauma and PG (particularly PG₂) may stimulate differentiation and proliferation of osteoprogenitor cells during early bone healing. It has been reported that NSAID, such as Diclofenac acid, ibuprofen, indomethacin, aspirin, salicylic acid decreased ingrowths of bone into porous coated implants and decreased mineral content in rabbits. In view of the above fact, this chapter is undertaken to investigate the effects of one potent NSAID (Flunixin Meglumine) on fracture healing.

The study is conducted in ten clinically healthy adult New Zealand White rabbits of either sex divided into two groups (A and B) consisting of five animals each. In all animals, mid-shaft simple transverse fracture is created in both the ulnae under thiopental (2.5%) anaesthesia. In animals of group A, 0.25ml (12.5 mg) Flunixin Meglumine (Ilium Flunixil) is injected intramuscularly on alternate days from day 5-20 postoperatively whereas, in group B no drug is given. Lateral and anterio-posterior radiographs are taken on day 0, 10, 20, 30 and 40 post-fracture. The radiographs are observed for progress of fracture healing and complication, if any, at different interval. The specimen for histopathological study is collected from the healed site of test bones immediately after euthanizing the animals on day 40. Every specimen is consisted of both healing and adjacent host bone. The bone sections are preserved in 10% formalin for 9-10 days and then are decalcified using Goodling and Stewart’s solution (15% formic acid, 5% formalin and 80% distilled water). Completely decalcified sections are then processed routinely for H&E staining. These sections are observed for the status of healing at the fracture site, at cellular level.

Minimally invasive percutaneous osteosynthesis (MIPO), or minimally invasive fracture repair, was introduced into human orthopedic surgery during the 1990s because of several distinct advantages over traditional open reduction techniques. In MIPO, large incisions to facilitate open reduction are avoided and implants are introduced through small stab incisions in the skin. This led to advent to more biology friendly techniques. These biological techniques lay stress upon maximal preservation of blood supply around the fractured bone by minimal direct handling of the fracture environment. MIPO offer advantages which include preservation of the fracture hematoma; less surgical trauma to the surrounding soft tissues, reduced operative time therefore, decreased risk of infection and ultimately leading to indirect bone healing with abundant callus. Minimally invasive plate osteosynthesis (MIPO) is a novel technique for application of principles of biological fracture healing with a philosophy of dealing with soft tissues with utmost respect. Following advancements in implant technology and development of techniques of indirect fracture reduction this technique gained more popularity. The evolution of MIPO began with the use of bridge plating. Initially a conventional plate is applied for comminuted femoral fractures using long incisions but with preservation of the vastus lateralis muscle resulting in healing with abundant callus. Subsequently, the size of incisions got decreased, rather two small incisions are given at proximal and distal ends and plates are bridged sub muscularly over the fracture fragments. This technique causes minimal distress to soft tissues and bone, provides access to the bone through soft tissue windows, with minimal or no contact with the fracture by indirect reduction tools and leaving behind minimal foot prints.

One of the most common fractures seen in the dog is comminutuion of femoral shaft, often related to sever impact from an automobile accident or jump from a height. Comminuted fractures are characterized by one or more butterfly fragments and assorted small bone chips that are especially difficult to align accurately and stabilize completely. These complicated fractures require sophisticated repair technique that are capable to resisting compression, bending and rotational forces. Rebuilding of comminuted fractures so that all fragments are accurately aligned and gaps are eliminated is often impossible. Non-union and osteomylitis have their highest incidence in these fractures. Over the years, several techniques are tried to treat comminuted femoral fractures with different success rate and there is a lack of uniform fracture presentation. Hence, it will be difficult to compare different techniques in a particular type of fracture. The present chapter is, therefore, undertaken to evaluate radiographically and histopathologically the efficacy of three different internal fixation techniques in the management of comminuted diaphyseal femoral fracture in dogs.

Clinically healthy, adult mongrel dogs (15) of either sex are randomly divided into groups A, B and C of 5 animals each. In all the animals unilateral comminuted diaphyseal femoral fractures is created under general (thiopental - 5%) anaesthesia and is immobilized with intramedullary (IM) pinning with cerclage wiring (Gr. A), neutralization bone plating (Gr. B) and neutralization bone plating with cerclage wiring (Gr. C) respectively. All the animals are administered broad spectrum antibiotic (streptopenicillin @ I g intramuscularly (dog/day) and analgesic (diclophenac sodium @ l mg/ kg b. wt. daily) and surgical wounds are dressed daily with povidone iodine and antibiotic cream for 5 days postoperatively.

Lateral and oblique views of radiography are taken at the operated site just after the operation and subsequently on days 15, 30, 45 and 60 postoperatively. The radiographs are observed for status of fracture reduction and fixation, progress of healing at the fracture site and complications like fixation failure, osteomylitis etc., if any, at different intervals. Bone sections are collected from the fracture site including adjacent normal bone after sacrificing the animals on day 60. The sections are decalcified using Goodling and Stewart’s solution (80% distilled water, 15% formic acid and 5% formalin) and then processed routinely for H & E staining for histopathological studies

Among the epiphyseal and metaphyseal fractures of the different long bones, fractures of the proximal tibia are quite commonly reported and require special attention due to their proximity to the compound stifle joint. Hence, a standard fixation technique is needed to treat such fractures, which also permit early ambulation and preserve range of joint motion in addition to providing rigid fracture fixation. Different treatment modalities have been tried for fixation of metaphyseal fractures with variable results. No single method is appropriate in all circumstances and treatment indication often overlaps. Therefore, in this present chapter, an attempt has been made to evolve a standard technique for the management of such fractures.

Ten clinically healthy mongrel dogs are maintained under uniform housing, feeding and management conditions, acclimatized, immunized against rabies, dewormed and randomly divided into two groups (A and B) of five animals each. In all the animals unilateral metaphyseal fracture is created in the proximal tibia under general anaesthesia with intravenous thiopental sodium (5%). In the animals of group A, the fracture is immobilized with cross intramedullary Steinmann pinning with interfragmentary wiring, whereas, single intramedullary pinning along with interfragmentary wiring is performed in the animals of group B. Antiseptic dressing of the wounds is done daily for 1 week with povidone-iodine. All the animals are administered Enrofloxacin at the dose rate of 5 mg/ kg b.wt intramuscularly daily for 5 days posoperatively. Skin sutures are removed on day 10 post-operation

Healing of fracture is a consequence of cellular behaviour in a living organism and as such can be modified by almost all endogenous or exogenous factors that affect the metabolic function of cells. These factors include transforming growth factor-β, bone morphogenetic proteins, hormones, vitamins and prostaglandins. The anabolic hormones like thyroxine and insulin accelerate bone formation in experimental animal. Hence, this chapter is proposed to evaluate the effects of thyroxine and insulin therapy in the management of tibial metaphyseal fracture in dogs.

Clinically healthy, adult mongrel dogs (15) of either sex are randomly divided into three groups (A₁, A₂ and A₃) of 5 animals each. In all the animals, unilateral metaphyseal fracture is created in the proximal tibia and then immobilized with cross intramedullary pinning with interfragmentary wiring under thiopental (5%) anaesthesia. All the animals are administered broad-spectrum antibiotic (streptopenicillin @ 1 g intramuscularly /dog/day) and analgesic (5 ml I/M daily) and surgical wounds are dressed daily with Povidone iodine and Lorexane cream for 5 days postoperatively. In group A₂, thyroxine sodium tablets (0.013 mg/kg body wt, orally) and in A₃, insulin injection (2 IU/kg body wt, s/c) are given on day 7 and then on every alternate day till day 45 postoperatively, at one specific time. Group A₁, is remained as control, in this group no hormonal therapy is given.

Craniocaudal and mediolateral radiographs of the fracture site are taken immediately after surgery and subsequent on days 15, 30, 45 and 60 postoperatively. The radiographs are observed for status of fracture reduction and fixation immediately after surgery and subsequently for the maintenance of reduction, progress of fracture healing and complication, if any, at different intervals.

Bone grafting is important in the treatment of non-unions, delayed unions, joint arthrodesis, and filling of bone cavities and the replacement of bone lost due to cyst, trauma or tumours. An ideal bone graft or substitutes should be a material that is biologically inert or bioadaptable, a source of osteogenesis, having osteoconductive property, act as a mechanical support, readily available, easily adaptable to the site in term of shape and size and replaceable by the host bone. The beneficial effect upon osteogenesis of impregnating allograft bone with autogenous red marrow or autogenous citrated plasma has been the subject of current research. It is claimed that autogenous fresh bone marrow and citrated plasma are two useful contributors for osteogenesis. Biodegradable and bioadaptable ceramics like ALCAP (Aluminum-calcium-phosphorus oxide) seem to be the most promising biomaterials for correcting bone defects, since these ceramics encourage self-replacement by endogenous bone. However, use of bone grafts and ceramics with autogenous bone marrow or citrated plasma has not been investigated so far. This chapter is undertaken to evaluate bone marrow and plasma impregnated bone allografts and ceramic implants in fracture healing in goats.

Study protocol & grouping

Eighteen, locally available nondescript male/female goats of 12-14 months of age are selected on the basis of their clinical status and are kept under observation for a period of one month before start of experiment. The animals are housed in their shed and are allowed to graze in the surrounding pasture. They are kept on standard feed and fodder throughout the experiment. The animals are randomly divided into six groups consisting of three animals each. Two trials of a similar experiment are performed in each goat. A total of 36 trials are conducted to evaluate different bone grafts and ceramic implants (six trials for each group with three animals each): Group A, frozen decalcified allogenic bone grafts; Group B, frozen decalcified allograft impregnated with autogenous bone marrow (composite bone graft); Group C, frozen decalcified allograft impregnated with autogenous citrated plasma (composite bone graft); Group D, ALCAP ceramics; Group E, ALCAP ceramics impregnated with autogenous bone marrow; Group F, ALCAP ceramics impregnated with autogenous citrated plasma.

Physiotherapy may be defined as the use of physical techniques like massage, exercise, heat, cold, sound waves, electric current etc for the treatment of injuries and movement dysfunction. Physiotherapy deals with the treatment of diseases by physical methods. It is used for treating injuries, strain, spasm, painful conditions, sprain of tendons, paralysis, postoperative trauma etc. It improves functioning of nerve, muscles and bones. The aim of physical therapy is the restoration of function and promotion of tissue healing by assisting normal physiological processes. The physiological response to physical therapy is its effect on the vascular supply; this in turn reproduces similar changes in deeper tissues.

LAND VERSUS SOIL

Land is a part of Earth’s surface that is not covered by water. It is used for agriculture, building houses, of?ce buildings, schools, hospitals, roads, railroads and even water canals. Land is measured by area [length (l) × width (w)] and the units are square meters (m²), square centimeters (cm²) etc. On the other hand, soil is Earth’s crust, which could vary from a few centimeters to a few meters in thickness (depth), needs a measure of volume [length (l) × width (w) × depth (d)] and the units are cubic meters (m³), cubic centimeters (cm³) etc. Soil is thus a three-dimensional natural body on Earth’s surface that provides anchorage to growing plants/ trees and shelter to soil biota and is responsible for the storage of water and plant nutrients, which are essential for crop production. In addition, it helps in the biodegradation of soil pollutants and puri?cation of ground water, the major source of drinking water in the world. Soil feeds all living beings on Earth and its degradation is one of the reasons for inadequate human nutrition

INTRODUCTION

In biology, fertility is de?ned as capacity to produce off-springs; however, in Soil Science a ?ne difference is made between a fertile and a productive soil. Soil Productivity is the ability of a soil to produce a crop using the entire spectrum of its physical, chemical and biological attributes, while Soil Fertility refers to the capacity of a soil to supply all essential plant nutrients in the desired amounts. Thus, soil fertility management is basically the nutrient management. To put it in simple words, a productive soil is always fertile, while a fertile soil may not be productive for a variety of factors, such as lack of adequate moisture in drier regions or lack of adequate air due to water-logging for most upland crops. Of late, a term ‘ Soil Health’ has been introduced. Soil Health is an assemblage of chemical, physical and biological parameters that closely relate to native or acquired production capacity and sustenance of ecologically important regulatory role (Katyal et al., 2016). It is measured against prede?ned parameters of soil’s status of fertility, compact ability, erodibility and biology. This again tends to relate soil fertility to nutrient content, availability and management.

German chemist Justus Freiherr von Liebig (1803–1873), Professor at the University of Geissen and the French chemist Jean-Baptiste Joseph Dieudonne’ Boussingault (1801–1887), Professor at the University of Lyon and later Chair, Conservatoires des Artes et Matier in Paris are to be credited for analyzing the plants and coming with the idea that plants absorbed nitrogen and other mineral nutrients from the soil for their growth. D.I. Arnon and P.R. Stout, Plant Physiologists and Plant nutritionists at the University of California, Berkeley, USA, grew plants by hydroponics using pure chemical compounds and established following 3 criteria for the essentiality of nutrients for plant growth

All life on planet Earth is carbon centered; hereditary characters are controlled by DNA and RNA, growth by proteins and activities by energy from carbohydrates and fats – all these are carbon compounds. Not only this, but the life also ends as carbon compounds CO₂ or CH₄, depending on aerobic or anaerobic decomposition. Incidentally soil fertility also depends very much on soil organic carbon (SOC). In ancient days, farmers used to apply manure to maintain soil fertility and even now, urea, the nitrogen fertilizer used in the largest amounts, is a carbon compound. All living forms on the Earth including all plant and animal species and their activities are a part of global carbon cycle. The carbon cycle is the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and atmosphere of the earth.

SOIL WATER

Soil water and oxygen share the pore space in soil and generally the oxygen content is determined by the water content, which is added by irrigation or rains and then keeps on changing due to evapotranspiration. Water is the vehicle by which most nutrients move from the soil to root surface. But for the lowland rice, nutrients are most available to plants at ?eld capacity moisture (about 0.3 atmosphere soil water tension) and the availability decreases as the moisture content decreases to wilting point (about 15 atmosphere tension). That is why rainwater or irrigation increases nutrient availability, while extremely dry condition decreases it. There is thus a signi?cant interaction between water and nutrient availability in soil (Singh et al., 2014). In a study in India (Singh et al., 1980) the yield of wheat was signi?cantly affected by irrigation water and nitrogen treatments; maximum yield was obtained with irrigation at 50% available soil water in 60 cm soil depth and 120 kg ha ^–1 nitrogen addition. A study on wheat at Delhi (Kumar et al., 2015) very well shows the effect of irrigation water on yield and uptake of nutrients (NPK) (Table 5.1).

Introduction

Nitrogen constitutes 78% of the atmospheric gases and there is about 75,000 Mg N on each hectare of land. However, 99% of the atmospheric N is as N₂ and is inert and non-reactive, while the rest 1% or even less is the reactive-N. Reactive-N is linked with H, O and C and is responsible for the creation and sustenance of all life on the planet Earth. Nitrogen is the key nutrient that separates proteins from carbohydrates and fats, the three major macronutrients for humans. As a component of proteins, N is present in DNA and RNA, which carry the hereditary characters and then as the major constitute of the body muscles of humans (and animals). Plant growth and crop production are also very much dependent on the adequate availability of N in soil.

Fertilizer N has been the key input in increasing cereal production throughout the world. In India, it made possible to achieve the yield potential of high-yielding dwarf varieties of wheat that led to ‘Green Revolution in 1968’. Nitrogen fertilization also increases protein content in wheat grains (Rajeswara Rao and Prasad, 1987) and leads to increased production of proteins in cereals (Prasad and Shivay, 2015). Cereal production in India increased from 42.4 million tonnes (Mt) in 1950–51 to 259.6 Mt in 2017–18, while fertilizer N application increased from 0.05 Mt to 16.96 Mt. However, the average agronomic ef?ciency of N (AEn) in India for cereals is only 9.5 kg grain kg–1 N (Sharma and Batra, 2011) as compared to global average of 24 kg grain kg–1 N for maize, 22 kg grain kg–1 N for rice and 18 kg grain kg–1 N for wheat (Ladha et al., 2005). Besides this, more disturbing is the fact that in irrigated areas the AEn declined from 13.4 to 3.4 kg grain kg–1 N during 1970–2005 (Biswas and Sharma, 2006). This is due to poor N management. Bulk of fertilizer N is applied broadcast on surface in most crops.

As compared to total N soil total P is present in much smaller amounts in soil; it is roughly about 10% of total N. Further, while N in soil is in the largest amount in surface 0 to 15 cm layer, soil P may be the same or in larger amounts in the sub-soil. Again, organic P constitutes only a small portion of total P. Thus, the Chemistry of soil P is generally centered on inorganic P. Total and organic P in some Indian soils is given in Table 8.1; hill soils had the highest and the desert soils the least total as well as organic P.

FRACTIONS OF INORGANIC P

All P in soils has originated from apatites [3 (Ca₃ (PO₄)₂.Ca×₂, where ×₂ could be F, Cl, (OH) or CO₃). Large deposits of apatites form phosphate rocks, which are the major materials for making phosphate fertilizers. As the soil weathering proceeds, P in apatite reacts with Al, Fe and other cations and forms compounds of different solubility. A knowledge of these can help in understanding the P-supplying capacity of soils. A number of chemical extractants and resins are used for determining different fractions. In general, 7 fractions of inorganic soil P are mentioned. These are: saloid-P (soluble and loosely bound P extractable by NH₄Cl), labile P (determined by using anion-exchange resins), Al-P (NH₄F extractable), Fe-P (NaOH extractable), Ca-P (H₂SO₄ or HCl extractable), reductant-soluble- P (CDB or sodium citrate-sodium dithionite-sodium bicarbonate extractable) and occluded P (CTB followed by NaOH extractable)

Out of the three primary plant nutrients (NPK), potassium (K) is taken up by crop plants in the largest amount, yet as compared to N and P, only a tiny fraction of it goes in the grain or seed. For example, Shivay et al. (2015) reported from a study on rice that about 20 kg N, 6 kg P (13.7 kg P2O5) and 46 kg K (55.2 kg K2O) was taken up by the crop to produce each Mg or tonne (1,000 kg) of rice kernel; however, only 4.3% of K taken up by the crop was found in the rice kernel as compared to 44% of N and 66% of P taken up by the crop. Some information on N, P and K removed per tonne of grain/ seed for some crops is given in Table 9.1.

Secondary nutrients is a triad of three essential plant nutrients namely, Calcium (Ca), Magnesium (Mg) and Sulphur (S). Of these three, Ca and Mg are taken up by plants as cations, while S is taken up as anion SO4 2–. Among the secondary plant nutrients, sulphur is emerging as a major plant-nutrient de?ciency in crops grown in the Indo-Gangetic Plains, spread over 13 million ha in Pakistan, India, Nepal, and Bangladesh (Khurana et al., 2008). From the Indian point of view, S de?ciency has emerged in a large part of the country and needs to be attended. Uptake of Mg and S by some crops is given in Table 10.1.

There are nine essential micronutrients, namely, iron (Fe), manganese (Mn), zinc (Zn), copper (Cu), boron (B), molybdenum (Mo), chlorine (Cl), vanadium (V) and nickel (Ni). Out of these, Fe, Mn, Zn, Cu and Ni (Dominic et al., 1978) are taken up by plants in their ionic form X²⁺, Mo as MoO^2-, chlorine as Cl^– form and boron as boric acid (H₃BO₃) or as its ionic form B (OH)₄ ^–. The absorption of vanadium by plants has received only limited attention (Lepp et al., 1983); it may be absorbed as cation V or vanadyl (VO²⁺) and anion vanadate (VO₄ ^3–). Bulk of the information is available on Fe, Mn, Zn and Cu, because of the acceptability of the single DTPA (Diethylene triamine pentaacetic acid)–CaCl₂ extraction test of Lindsay and Norvell (1978) for availability of all these four nutrients followed by their estimation on Atomic Absorption Spectrometer (AAS). Available B is estimated by hot 0.15 M CaCl₂ extraction method (Saha and Singh, 1997). Molybdenum data base is poor, because its determination is dif?cult and Mo de?ciency in crops has not been much noticed in India. Chloride is available in plenty in irrigation water and soil in India and has not received much attention in India.

Internationally maize (Zea mays) and citrus (Citrus sp.) are reported to largely suffer from Zn de?ciency, for which these are considered as marker plants. Zinc de?ciency in maize results in pale or whitish top young leaves and the de?ciency is referred to as 'white bud' (Camberato and Maloney, 2012). In citrus, Zn de?ciency results in ‘rosette’ (cluster of stiff leaves at the end of young shoots) formation (Brennan, 1993). Zinc de?ciency in India was ?rst reported in rice by Nene (1966) at the Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, and given the name ‘khaira’ disease due to dark-brown-coloured spots resembling kattha (Acacia catechu extract used in paan – the betel leaves) on the leaves of zinc de?cient plants. Soon All India Coordinated Project on Micronutrients was launched by the Indian Council of Agricultural Research (ICAR) with headquarters at the Punjab Agricultural University, Ludhiana, which was later shifted to the Indian Institute of Soil Science, Bhopal, Madhya Pradesh. About half of the cultivated soils in the India are de?cient in available zinc. Zinc de?ciency is most in Maharashtra and Karnataka and rice-growing states of north and northeast (Table 12.1). A good response of cereals to Zn fertilization has been reported (Rattan et al., 2008).

Boron (B) de?ciency has been realized as the second most important micronutrient constraint in crop production after that of Zn in the world (Ahmed et al., 2012). However, in Nepal, B de?ciency is more wide-spread than Zn de?ciency, as 80 to 90% of soil samples were de?cient in B, 20 to 50% in Zn and 10 to 15% in Mo (Anderson, 2007). In India, B de?ciency has increased from 2% of the soil samples de?cient in B in 1980s (Katyal and Vlek, 1995) to 52% soil samples in 2000s (Singh, 2012). Total B content in Indian soils varies from 7 to 630 mg kg^–1 soil (Kanwar, 1976); being the highest in arid regions of the country and the lowest in wet humid regions of the country (Behera et al., 2009; Prasad et al., 2014). Boron de?ciency is most in the heavy rainfall areas of Western Ghats of Maharashtra, Karnataka and the eastern states of Bihar, Odisha, Jharkhand and Chhattisgarh states of India (Fig.13.1). The wide-spread de?ciency of B in India can be seen from the fact that B fertilization recorded the highest bene?t : cost (B : C) ratio in rice–wheat cropping system at Palampur (Himachal Pradesh), Ludhiana (Punjab), Faizabad, Modipuram and Varanasi (Uttar Pradesh), Pantnagar (Uttarakhand) and in rice–rice cropping system at Maruteru (Andhra Pradesh), Karjat (Maharashtra) and Jorhat (Asom) (Singh and Goswami, 2014). Response of wheat to B fertilization is also reported from Bangladesh (Halder et al, 2007).

Before the discovery of chemical fertilizer in early 20^th century, organic manures and growing of legumes were the ways of replenishing soil fertility. The only other way was leaving land fallow for a few years before its re-cultivation, a practice followed in shifting cultivation (jhuming) (Garbyal, 1999). This was also true for India, where although the ?rst single superphosphate plant was set up in 1906 in Ranipet (Tamil Nadu), the real use of fertilizer started with the manufacture of urea, the ?rst plant for which was set up in 1959 at Sindri (Bihar) (Tandon, 2014). Organic manures could meet crop-nutrient needs in early days because the average grain yield of most cereals was about 1.5–2.0 t ha^–1, while the average yield of pulses was 0.5–0.75 t ha^–1. However, the crop production scenario changed rapidly after the introduction of dwarf, high-yielding varieties of wheat from Mexico, which led to the “Green Revolution” (Swaminathan, 2013). This was followed by the development of semi-dwarf, high-yielding varieties of rice and hybrids of maize, sorghum and pearl millet. These varieties/ hybrids of cereals needed 100–150 kg N ha^–1 in one growing season, and this could be met only by urea or other N fertilizers; organic manures had no chance and their use became almost nil over a period of next 25 years or so. Well-off young farmers cannot even think of making manure heaps or compost pits, the job is too hard and not a clean one. However, what is ignored is the fact, that organic manures not only supply plant nutrients but also build up soil organic matter, which improves soil physical properties, helps in storing moisture and is the elixir of life for the soil biota (Lal, 2014). A large numbers of reports are available on the effect of adding organic manures and crop residues on improving soil physical (Hati et al., 2007; Brar et al., 2015) and chemical and biological properties of soil (Prasad et al., 1999; Prasad and Mishra, 2001;Sharma et al., 2009; Prasad et al. 2014). Thanks for the organic farming (Prasad, 2005), the interest in organic manures and composts has increased in India and it is now a sought after material. However, it has not entered the main stream of crop production.

Soil-rejuvenation power of legumes in crop rotations has been known in several parts of the world since ages. It is mentioned in the Indian agriculture of the Chalcolithic period (ca 1000 BC) (Raychaudhuri and Mira, 1993), in Chinese agriculture in the Han dynasty (ca 2nd century) (Hsu, 1980) and in Roman agriculture (White, 1970). Legumes can be ?tted in cropping systems in India in a number of ways, such as, a crop in a cropping system, a catch crop in an intensive cropping system, an intercrop and as a green manure. A brief discussion on these follows.

Fertilizer recommendations are generally made on the basis of soil test. Recommendations of fertilizer for top-dressing are best made on tissue testing.

SOIL TEST

A number of approaches have been adopted to increase the precision of soil-test values in making fertilizer recommendations. Four most important ones are discussed.

Low-Medium-High Approach

Making fertilizer recommendations based on soil test for a nutrient involves conducting a large number of ?eld experiments on soils similar to those which are intended for making recommendations. For an individual nutrient (say P for example) experiments are conducted with graded doses of P on a crop for which the fertilizer recommendations are to be made. Thus, agronomic experiments are to be conducted for each crop on each kind of soil. The response curve can then be divided into three sections: a, low soil-test value and high response to fertilizer zone; b, medium soil-test value and medium response to fertilizer zone; and c, high soil-test values and no response to fertilizer zone. In India, this was done

The introduction of high-yielding varieties of wheat and rice, the development of intensive cereal–cereal rotations (rice–wheat, rice–rice, hybrid maize–wheat), application of high doses of N (above 100 kg N ha^–1 to each crop) without adequate P and K application, increased use of high-analysis fertilizer (urea and diammonium phosphate in place of ammonium sulphate and superphosphate) and ignoring the application of organic manures led to heavy depletion of P, K, S, Zn and other plant nutrients, which led to wide-spread de?ciencies of P, S and Zn in Indian soils. These de?ciencies of nutrients led to focus on integrated nutrient management.

Plant nutrients are important for increased production of food for the ever-increasing world population. Of the plant nutrients, primary nutrients N, P and K are applied to ?elds each season in fairly large amounts. In addition to increasing crop yields, they also impact the environment. This is briefly discussed in this chapter; only main points are made here.

NITROGEN

Nitrogen is blamed the most for environmental degradation. It contributes to eutrophication of inland and sea-waters, enrichment of air with NH₃ and N₂O and even with global warming. However, it is almost impossible to grow more food without additional nitrogen. It is estimated that by 2050 about 250 million tonnes (MT) of fertilizer nitrogen may be needed to meet global increased food demands as against an estimated current consumption of 116 MT

1.1 Introduction

Fungi are chlorophyll-less thallophytic plant. Due to absence of chlorophyll, they are heterophytes which depend on other form of life for food. They grow in various habitats and show much diversity in their structure, physiology and reproduction. They evoloved long back from the ancient time.

Their existence was recorded from Pre-cambrian period. Information from ancient literature indicates that the fungi were used as food by men. At present, the fungi are used in medicine as well as food in addition to other aspects. The fungi cause diseases in crop plants (spots, rusts, smuts etc.) and on human beings (Aspergillosis, Blastomycosis etc.).

At present biologists use the term fungus (fungus mushroom, from Greek, sponagos = sponge) to include eukaryotic, spore bearing, achlorophyllous organism that generally reproduce sexually and asexually and whose usually filamentous, branched somatic structure are typically surrounded by cell wall containing chitin or cellulose or both of these substances, togather with many other complex molecules

More than 1.5 million species (Hawksworth 2001; Kirk et al., 2001) of fungi have been recorded, but their number may be much more than the actual record. The subject which deals with fungi is known as Mycology (mykes — mushroom; logos—study) and the concerned scientist is called mycologist. The various definitions of fungi as proposed by mycologists are:

Alexopoulos (1962) defined fungi as “nucleated, spore-bearing, achlorophyllous organisms which generally reproduce sexually and asexually and whose usually filamentous, branched somatic structures are typically surrounded by cell walls containing cellulose or chitin or both”.

Alexopoulos and Mims (1979) defined fungi as eukaryotic spore bearing, achlorophyllous organisms that generally reproduce sexually and asexually, and whose usually filamentous, branched somatic structures are typically surrounded by cell walls containing chitin or cellulose, or both of these substances, together with many other complex organic molecules.

According to G.C. Ainsworth (1973) the fungus is free-living, parasitic or mutualistic, saprotrophs, necrotrophs or biotrophs and devoid of chlorophyll. Cell wall composition very variable, majority contain chitin and glucans, reserve materials glycogen, oil and mannitol, characteristic disaccharide and trehalose. Some yeast-like but majority with thread-like filaments, hyphae, branched profusely to form the vegetative mycelium on which spores are produced, asexually or sexually, free on hyphae or enclosed in complex reproductive structures. Separated mainly on morphology of the latter.

2.1 Divisions: Myxomycota

These are wall-less and quite unusual organisms only included in the fungi as mostly studied by mycologists. Possess either a plasmodium, a mass of naked, multinucleate protoplasm, which feeds any ingesting particulate matter and moves by amoeboid cells. Both of slimy consistencies hence slime molds. Four classes:

2.1.1 Class: Acrasiomycetes (Cellular slime molds)

Assimilative phase, free living amoebae which aggregate to form a pseudoplasmodium before reproduction.

Fungi are achlorophyllus so they have to depend on other organisms hence heterotrophic nutrition. Depending on the nutrition, fungi are classified as Saprophytes, Parasites and Symbionts.

3.1 Saprophyte (sapros = rotten; phyton = plant)

Fungi which get their nutrition only from dead organic are called saprophytes ex: Saprolegnia, Rhizopus, Mucor, Alternaria etc.

3.1.1 Facultative saprophyte (Facultas = ability)

Ability of a fungus to become saprophyte. It is a parasite ex. Ustilago

3.1.2 Obligate saprophyte (obligate = to bind itself)

When they strictly get their food only from dead organic matter and can never become parasites are called obligate saprophyte ex. Mucor.

Reproduction in fungi is the formation of new individuals having all the characters of species. It is of two types. Asexual, somatic, or vegetative reproduction does not involve the union of nuclei of sex cells or sex organs. Sexual reproduction is characterized by the union of two opposite nuclei. During reproduction entire thallus is converted into one or more reproductive units. It is called holocarpic fungi (holo = whole, korpos = fungi) ex. Plasmodiophora and Synchytrium. In Plasmodiophora vegetative body is plasmodium, which is transformed into reproductive structure. In some fungi only a part of thallus is transformed into one or more reproductive structures. (eu = true, good, carpus = fruit). These fungi are known as eucarpic. Both somatic and reproductive structures coexist. Ex. Rhizopus, Puccinia and Helminthosporium.

There are great variations in the life cycles of fungi. Raper (1954, 1966b) recognizes seven basic types.

5.1 Asexual cycle

In which sexual reproduction apparently lacks and diploidy is restricted to somatic diploids. The entire groups known as Fungi Imperfecti and numerous other species which clearly belong to various groups of the perfect fungi such as Penicillium notatum have this life cycle. Certain benefits of sexuality are provided here in many of the sterile forms by para sexual recombination.

In the classification given below only those groups have been given emphasis which contain plant pathogenic fungi or which are important from taxonomic point of view. The description includes only critical features.

For growing fungi, a wide range of media are used. Media affect colony morphology and color. For utilizing different carbon sources some fungi lack the necessary enzymes. For growth and reproduction all fungi require several specific elements. The requirements for growth are generally less specific than for sporulation, so it is often necessary to try several types of media when attempting to identify a fungus in culture. Sporulating cultures should be used because repeated transfers of a pathogen on artificial media usually result in loss of sporulation or pathogenicity or both. Transfer should be made using spores and cultured alternately on nutrient rich and poor culture media. Most fungi thrive on potato dextrose agar (PDA), but in some fungi excessive mycelial growth is obtained at the expense of sporulation. Similarly, wood-inhabiting fungi and dematiaceous (dark pigmented) fungi often sporulate better on Corn meal agar (CMA) or Oat Agar, both of which have less easily digestible carbohydrate than PDA. Cellulose-destroying fungi grow on a weak medium such as Water Agar (WA) or Potato Carrot Agar (PCA). By adding pieces of tissue, such as filter paper, wheat straw, rice, grains, leaves or dung, often produces good sporulation dependent on the organism grown. Some special methods of inducing sporulation in fungi.

Diagnosis of plant diseases require some knowledge of light microscopy to examine infected tissues for the presence of plant pathogens. Most of the pathogens and the diseases caused by them can be identified quickly by using different methods such as section or cutting of infected tissue, squashes of scrapping of plant surface. Homecare, the detail study enquires ultrastructural examination of the pathogen.. Electron microscope rely on a beam of electrons produced from a hot filament (e.g. tungsten) and its power of resolution is much greater than light microscope. Electron microscope are of two type

When any serious work is undertaken involving the use of living cultures it is necessary to keep these alive for use during the work and for future reference.

This can be done either by growing on a suitable substrate and transferring to fresh media, as the nutrient is used up or by treating the cultures in some way, which halts metabolism until they are revived for use. The former method is time consuming and cultures are at risk whenever they are handled, so various means are devised which can lengthen the periods between sub culturing. The latter methods tend to be complex and expensive.

1.1. Prologue

In present era, agriculture is a cause of global concern in the context of price volatility with a rising trend growing concerns for food security and resultant trade restrictions, global economic conditions in the recent past, the forecasted rate of reduction of growth of agricultural land over the next two decades, increasing mismatches between supply of agricultural products in relation to growing demand and the climatic changes which are wielding pressures on agricultural production. Thus, enhancing agriculture production and productivity have emerged as a global challenge. India, with 2.4 per cent of the world’s geographical area, is the largest producer of pulses, tea, and milk and second largest producer of fruits, vegetables, wheat, rice, groundnut and sugarcane in the world but supports about 16.2 per cent of the world’s population. Coupled with small scale land holdings and deep rooted poverty in rural areas, the magnitude and dimensions of challenges for agriculture policy-makers have increased manifold. So far as the agriculture sector in Odisha is concerned, it contributes only 15.6 percent in 2013-14 towards State Gross Domestic Product (SGDP), but provides employment and sustenance to more than 60 percent of the total workforce of the State. In this sense, the agriculture sector is still the mainstay of the economy of Odisha. According to the Economic Survey 2013-14 of Odisha, despite wide annual variations in its growth, the agriculture sector had grown at a rate of 12.72 per cent in 2012-13. However, a negative growth of 3.53 percent is anticipated during 2013-14 due to cyclonic storm Phailin and flash floods in the State in October 2013. The real per capita income of Odisha was Rs. 25,891 in 2013-14 which was around 65 per cent of All-India real per capita income of Rs.39, 961. According to the 68th round of National Sample Survey Organization (NSSO), the monthly per capita consumer expenditure (MPCE) for rural and urban Odisha is below the respective national averages. In the food and non-food consumption behaviour, an average Indian spends more than an average person in Odisha. In short, the above parameters pinpoint that the State of Odisha has been lagging behind the national economy & highlights the necessity of achieving higher growth on a sustainable manner across the sectors particularly the agriculture sector in order to uplift the society from underdevelopment & poverty. Though the contribution of agriculture to Net State Domestic Product (NSDP) has declined, the percentage of workforce engaged in agriculture has remained somewhat unchanged. This implies that there has been an overcrowding in agriculture without any noticeable increase in production.

2.1. Introduction

There are few studies on the performance and efficiency of Indian commodity derivatives market. Despite a considerable amount of empirical literature, there is no general consensus on whether or not the markets are efficient. As far as the role of futures contract in agricultural commodity is concerned, several studies have been attempted to examine their contribution towards agricultural development of any state and/or country. This chapter presents the review of existing literature on the concerned topic based on interrelationship among the spot and futures market in agricultural sector, role of futures market in discovering spot prices, futures market and commodity price volatility etc.

3.1. Introduction

This chapter intends to examine the economic importance of cotton, turmeric and castor seed in the agricultural economy of Odisha. Given the fact that Odisha is one of the major producing states of the country for these three crops, their physical markets have national level relevance in terms of determining prices. The chapter presents a brief profile of the agricultural economy of Odisha with a focus on these three crops and their supply conditions including cropping season, pattern, area under cultivation and productivity. Secondly, it tries to investigate the market structure, supply chain and marketing practices in cotton, turmeric and castor seed based on the data obtained from the secondary sources.

Indian economy is agro-based and agriculture is its mainstay as it constitutes the backbone of the rural livelihood security system. Agriculture has been and still continues to be the life line of the Indian economy since economic security is essentially predicted upon the agricultural and allied sectors. The agriculture sector encompasses crop production, animal husbandry, fisheries, agri-business, etc. Crop production depends upon crucial inputs such as good seeds, fertilizers, pesticides, irrigation, human labour, machinery and management.

As the largest private enterprise in India, agriculture supports more than 60% of the population, contributes nearly 19% to India’s Gross Domestic Product (GDP) and 11% to the total exports. Around 51% of the geographical area in India is already under cultivation as compared to 11% of the world average¹. Agriculture is also a social sector where non-trading concerns like food and nutritional security, employment and income generation, poverty alleviation, ecological and environmental concerns play a significant role.

4.1 Introduction

The present chapter starts with a brief description about the history of commodity futures market and emergence of commodity futures market in India. There after it highlights various functions of commodity futures market and their impact on farmers and various other stake holders in the supply chain. Finally, it tries to evaluate the utility of futures from the platform of commodity exchanges especially from MCX and NCDEX of India.

A simple definition of a commodity is a physical substance that can be extracted directly from the environment, processed and sold commercially. Natural resource is another term often used to describe commodities which occur naturally in or on the ground. Commodities fall into three main categories such as energy, metals and agriculture. As commodities can be sold, they have a price which is governed by supply and demand. Compared to many manufactured items, for example flat screen TVs, the question of supply and demand is paramount to how commodities are priced. The commodities that have always been a part of our day-to-day existence are also one of the finest investment avenues available. The wheat in our bread, the cotton in our clothes, our gold jewels, the oil that runs our vehicles etc are all traded across the world in major exchanges. Commodities can be traded on either spot markets, or in the form of futures. Spot markets are those in which the commodity is traded immediately in exchange for cash or some other good. In the form of futures (or options), what is traded is not the goods itself, but a contract to buy or sell the commodity for a certain price by a stated date in the future. Over the ages, commodities have been the basis for trade and industry. They have prompted commerce, encouraged exploration and altered the histories of nations. Today, they play a very important role in the world economy with billions of dollars of these commodities traded each day on exchanges across the world. Commodities today have become an attractive investment vehicle. In the current investment scenario, it is increasingly getting difficult for individuals and institutions to create a well-balanced investment portfolio. With uncertainty in interest ratio, it is tough for the investor to beat the ever-rising inflation. Averse to being over exposed to equity markets, the investors are left with limited choices… well no more!

5.1. Introduction

This chapter deals with the sample survey conducted on cotton, turmeric and castor seed farmers and RMC traders and Officials and recorded the awareness level about futures, user status, the reason for not using futures and perception about futures.

The research work was planned to understand the level of awareness of agri-commodity futures market among the farmers, RMC traders and Officials of Odisha. The methodology adopted for the awareness assessment was to collect related answers to the questions which helped to evaluate the level of awareness among the beneficiaries i.e. farmers, RMC traders and officials. Quantitative and qualitative data was collected from sample respondents. The study has been completed by collecting data from farmers, RMC traders and officials of Kalahandi and Kandhamal districts which are the highest producers of three sample commodities i.e. cotton, castor seed and turmeric in Odisha. The research was conducted with 150 farmers (50 each for cotton, turmeric and castor seed), 30 RMC traders and 30 RMC officials of Kalahandi and Kandhamal districts of Odisha. The profile of sample farmers is depicted below.

6.1. Introduction

This chapter deals with the sample survey conducted on cotton, turmeric and castor seed farmers and recorded various benefits observed by them by using Futures market as a platform for price information. Further, it tries to examine the price discovery efficiency of commodity futures market with the help of secondary data.

It is often believed that future price is a forecast of the price of a commodity during the maturity month of its futures contracts. It is far from true. The futures price of a commodity traded at an exchange market is not so much determined by the anticipated supply of and demand for that commodity in the maturity month of its futures contracts as by the cost of carrying the commodity till the maturity of such contract. That means the spot and future prices of any commodity are always determined by the same basic forces of the present and prospective demand and supply. The difference between the two prices represents merely the cost of carrying the commodity from the present to the future. Such cost may be positive or negative depending on whether the current (not the future) supplies are abundant or scarce respectively when the price of futures contracts of any commodity is in reality relied upon by the physical market functionaries in that commodity as a “reference” price for executing their forward transactions in either the domestic or export market, that price may deem to be “discovered” in the true sense. The application of such reference price for transacting a forward transaction in the physical market in that commodity, in fact facilitates the use of the same future contract for managing price risk for such forward transaction. Hence, the price discovery and price risk management are the two sides of the same coin and efficiency of price discovery is directly related to the price risk management. A commodity exchange or a derivative market is not a mechanism for controlling prices. An efficient futures market is one that discovers prices and provides effective mechanism for managing price risk arising from unavoidable price variations owing to shifts in demand and supply schedule. Prices are determined by the basic demand and supply forces and not the market. Markets reflect the supply and demand conditions from time to time through variation in prices.

7.1. Summary of Findings

This study dealing with the examination of various advantages of commodity futures market to farmers, RMC traders and RMC officials along with the level of awareness about this market among these selected beneficiaries is presented in brief. This chapter summarizes the findings. It begins with the interpretation of the significant findings derived from both secondary and primary analysis. This is followed by suggestions, the section on major contributions of the present study to the existing body of knowledge, on the role of commodity futures market in agricultural development of the state.

Microbiology is the branch of science which deals with the diverse minute forms of life such as bacteria, archaea, viruses, fungi, prions, protozoa and algae. The study includes structure, classification, growth and nutrition, natural habitat, genome, antigenic characteristics, virulence determinants, types of toxins produced, pathogenesis, diagnosis and ways to combat the infection caused by the microbes.

Taxonomy (biological systematics) is the branch of science which deals with classification of units or individuals on the basis of similarities and differences. The classification, nomenclature, and identification are three interrelated components of bacterial taxonomy (Cowan, 1965).

Classification: Classification is the arrangement of bacteria into groups (taxa) based on the similarities of certain characteristics. Presently 11,000 bacterial species is classified. At the current rate of 600 bacterial species / year it is estimated to take 1000 years to classify all the bacteria!

Nomenclature: It is the assignment of specific names to the taxonomic groups following the regulations mentioned in ‘International Code of Nomenclature of Bacteria’ (Euzeby, 1997). International committee on systematic bacteriology (International committee on systematics of prokaryotes, ICSP) standardizes the code. The committee is helped by a number of taxonomic subcommittees on different groups of bacteria. The Code can be amended by the Judicial Commission. The Code contains general considerations, principles, rules and recommendations on the naming of prokaryotes (bacteria) up to the rank of ‘Class’.

Microscope is the primary instrument of a microbiology laboratory and it produces enlarged images of small objects which are invisible by naked eye. With a microscope the operator can get a close view of minute structures which helps in examination and analysis. Examination of minute objects with a microscope is called ‘microscopy’. In microbiology, measurement of the microbial dimension observed under microscope is known as ‘micrometry’.

Types of microscopes

There are two types of microscopes i.e. light / optical and electron microscope depending on the sources of energy to create the image. The optical microscopes use the lenses and light (artificial or sunlight) to make an image. Following types of optical microscopes are available.

Bacteria can be defined as a group of diverse and ubiquitous prokaryotic single cell microorganisms. The size of bacteria varies with genera/species. In cocci the diameter varies between 0.5-1 µm. The measurement of bacillus / rod shaped bacteria is 4-8 µm ? 1-1.25 µm. The surface area and volume ratio of bacteria is very high. The nutrients are absorbed through a large surface area and it is rapidly distributed into a small volume. So the growth rate and metabolism of bacteria is very high. The bacterial cell mass is packed near the surface and no circulatory system is required to distribute the nutrients. The growth and metabolism rate of bacilli are more than cocci because surface area and volume ratio of a sphere (cocci) is lowest among all the geometrical forms.

Shape of bacteria

The shape of bacteria is mostly regulated by the rigid cell wall covering the bacteria. Different shapes of bacteria are observed.

Growth of bacteria can be defined as change of total population mass, not individual increase in size or mass. Macroscopically visible growth of bacteria on the solid medium is known as ‘colony’. It is estimated that if Escherichia coli are allowed to grow, a single bacterial cell can produce a daughter population with the mass of the whole earth within 2 days! In the environment the bacteria are not actively growing all the time. The mechanisms behind the growth-arrested states of environmental bacteria are not well understood.

Bacterial reproduction

Bacterial reproduction is an asexual process which occurs by binary fission, budding, fragmentation and condiospore or sporangiospore formation. There is no possibility of genetic exchange (reassortment) as it is originated from a single parent cell. Bacterial gene transfer occurs by transformation, transduction and conjugation methods (discussed later in details). These are one-directional DNA transfer methods and are not associated with reproduction. The donor bacteria can give the genetic material to the recipient and the vice-versa does not occur.

Binary fission: In binary fission, bacterial DNA is replicated first and then the parent cell separates. Each daughter cell receives a complete genome, identical to the parent cell. Bacterial DNA replication begins when the cells reach a specific mass. If the cell diameter is constant, longer cells will begin DNA replication earlier than the shorter cells. The shorter cells need time to reach a critical mass required for the initiation of DNA replication. The ugtP proteins were identified to be associated with shorter cells and delayed DNA replication in Gram-positive bacteria (Bacillus subtilis). It was confirmed later that the ugtP act as inhibitor for Z-ring formation.

Normal bacterial flora is the bacteria which live on another living being (human or animals) or inanimate object without causing infection

Opportunistic bacteria are part of normal bacterial flora which can produce infection during lowered immunity (immunosuppression) of host or when transferred into other parts of the body

Saprophytic bacteria live on dead or decaying organic matter Infection

Infection can be defined as a pathological condition occurred due to multiplication of microbes.

Intoxication can be defined as pathological condition due to ingestion of microbial toxin (e.g. aflatoxin produced by Aspergillus fungus).

Mycetism is the pathological condition due to ingestion of fungus (e.g. toxic mushroom) which produces toxicity within the body of the host

The genetics is the study of inheritance and variability of organisms. Bacterial genetics is a sub-field which specifically studies transmission of genetic information from one bacterium to its progeny or between the interbreeding bacteria and the expression of genetic information.

Mutation

Hugo de Vries (1848-1935, Dutch botanist) coined the term ‘mutation’. It is originated from a Latin word which means ‘to change’. The heritable change in bacterial DNA sequences is known as bacterial mutation. The mutation will generate a new type of bacteria with altered genotypical and phenotypical characteristics, known as ‘mutant’. The parent bacterial cell from which the mutants are generated is known as ‘wild type’. In nature bacterial mutation is a rare incidence. The spontaneous mutation occurs at a rate of 1 in 10⁵ to 10⁸. The phenotypical expression of mutation occurs quickly as the bacteria are haploid with shorter generation time.

Sir Alexander Ogston, a physician from Scotland, first elucidated the role of Micrococcus in formation of pus. He proposed the name ‘Staphylococcus’ (In Greek ‘staphyle’ means bunch of grapes and ‘kokkos’ means berry). Anton J. Rosenbach isolated two different species of Staphylococcus and named them according to the pigmented appearance of colonies i.e. Staphylococcus aureus (in Latin ‘aurum’ means gold) and Staphylococcus albus (in Latin ‘albus’ means white). The studies of Bumm (1885) established the relationship of Staphylococcus with human infections. Nocard (1887) and Guillebeau (1890) isolated Staphylococcus from mastitis in sheep and cattle, respectively and established its pathogenic role in animals.