eChapters

17.1 Introduction

Cotton is a major fibre crop of global importance and has high commercial value. It is grown commercially in the temperate and tropical regions of more than 100 countries. Specific areas of production include countries such as China, USA, India, Pakistan, Uzbekistan, Turkey, Australia, Greece, Brazil, Egypt etc., where climatic conditions suit the natural growth requirements of cotton. These include periods of hot and dry weather and adequate moisture obtained through irrigation. Cotton crop is considered as one of the most important cash crops that influenced the industrial and agricultural economy of the different cotton growing countries of world. Thus, cotton is an immensely important crop for the sustainable economy of these countries and livelihood of the farming community. Cotton crop is considered as one of the most important cash crops that influenced the industrial and agricultural economy of the different cotton growing countries of world. Cotton cultivation and textile industry provide livelihood to million persons, therefore any failure of cotton crop significantly influence the economic growth of cotton belt and textile sector.

The plants collect water by its root system available in the soil medium. A soil rich in nutrients cannot ensure success of crops unless the presence of satisfactory state of water and air, mechanical attributes and thermal regime. The physical properties of soil and plants greatly influence the movement, retention and use of water. The soil should provide sufficient pore spaces and size distribution and decomposition of rocks and for the movement and retention of water for plant needs. Rainwater, irrigation, groundwater, seepage, etc., contribute in replenishing the water in dried up soils. In all the cases thorough understanding of behavior of water is required to ensure the need of water to plants and optimize the use of irrigation water.

6.1 Soils

Soil is initially formed by the disintegration and decomposition of rocks and minerals and accumulation of biological residues. Usually the outer layer of the land surface is referred

In order to understand the generation of tides first we should understand the motions of earth with respect to sun and moon. Tides are affected by the orbit of the moon around the earth and, less so, by the earth around the sun. The orbital motion of earth with respect to sun and the orbital motion of moon with respect to earth are as shown in Fig.15.1.

Climate change drastically influence water availability, salinity and several adverse soil conditions which will have direct bearing on original yields. Abiotic stress factors influence growth and secondary metabolite production in higher plants. The influences are well marked. In fact, productivities depend on the changed ecosystem also. Secondary metabolites play a major role in the adaptation of plants to the changing environment and in overcoming stress constraints. This flows from the large complexity of chemical types and interactions underlying various functions: structure stabilizing, determined by polymerisation and condensation of phenols and quinones, or by electrostatic interactions of polyamines with negatively charged loci in cell components, photoprotective, related to absorbance of visible light and UV radiation due to the presence of conjugated double bonds, antioxidant and antiradical, governed by the availability of –OH, –NH2, and –SH groupings, as well as aromatic nuclei and unsaturated aliphatic chains, signal transducing. Several plant-abiotic stress stimuli systems evidenced the multiplicity of biochemical mechanisms involved in the protective role of secondary metabolites:

Chapter Overview

The need for gender analysis in various contexts, including the livestock sector, is vital for understanding and addressing differences and inequalities between men and women. This chapter explores the crucial role of gender analysis in the context of the livestock sector, focusing on animal husbandry and related activities. It delves into the significance of understanding and addressing gender disparities in livestock farming, highlighting the unique challenges and opportunities experienced by both men and women. The chapter emphasizes the need for equitable and sustainable development within the sector.

Introduction

There are a number of estimates of post-harvest losses. The most conservative estimates for the handling losses at about 10 per cent, a quantity good enough to feed at least 60 million people. Storage loss occurs due to quantitative and qualitative damages caused by insects, mites, fungi, rodents, birds, heat, moisture, etc. Several hundred insect species have been reported to be associated with stored grains and milled and processed foods, but some 50 of these species are considered injurious. Under Indian conditions, the most important insect pests of stored grains are Sitophilus oryzae (Rice weevil), Tribolium castaneum (Red flour beetle), Rhizopertha dominica (Lesser grain borer), Callasobruchus spp. (Pulse beetle), etc.

The use of repellents to ward off insects has been a very old practice of mankind. The simple fly swatters, feather dusters, hand fans, mosquito nets etc., are some of the physical repellants still in use. In our own country, mustard oil or turmeric (haldi) water is also used as a mosquito repellent. Fire and smoke are the two oldest insect repellents known to man. To get rid of wasp nests from our dwelling or ward off honeybees during honey extraction, smoke is normally employed. Similarly sandal dhoop is often burnt to purify air (i. e. to ward off insects) in our houses.

Chemicals that prevent insect damage to plants or animals by rendering them unattractive or offensive are called repellents. A more broad-based definition would be: non-poisonous or mildly poisonous chemicals that induce avoiding (oriented movements in insects away from their source. Repellents are more important in the protection of man and his animals from insect attacks than in the protection plants.

India is the second largest producer of fruits with a total production of 81.0 million tons from 6.98 million ha in 2012-13. The leading states in terms of area and production are:

A. CEREALS

1. Rice (Oryza sativa)

RD 60:20:20 kg/acre NPK

(Recommended by TNAU)

The word “Manure” is originated from the French word “Manoeuvrer” which refers to “work with soil”. The word Manure is also originate from Latin word “Manu” (hand) and operate (to work). Manures are the substances which are organic in nature, capable of supplying plant nutrients in available form, bulky in nature having low analytical value and having no definite composition and most of them are obtained from animal and plant waste products. Formerly, the word in use was “Dung ”in English (at present fertilizer).

1.1 Nematodes in Agriculture
Nematodes offer several ecosystem services that affect the nitrogen cycle, decomposition capacity, and control of pests within soil systems. Firstly, the effects on the nitrogen cycle have generated a growing interest in the beneficial effects of nematodes to improve soil nitrogen content. Specifically, soil disruption, during activities such as tillage, increases nitrogen availability as well as the abundance of bacteria that compete for nitrogen (Ducker James, 2021). In response to more bacteria, bacterial feeding nematodes also increase in abundance, and this stabilizes nitrogen availability and increases nitrogen mineralization in soil once again, which is key for crop growth and soil fertility. Secondly, nematodes are involved in the decomposition of organic matter in the soil. Free-living nematodes are particularly essential as they recycle nutrients in the soil, which is matched by the indirect effect of bacteria and fungi-feeding nematodes that feed on the bacteria and fungi which decompose organic matter. Together, the feeding activity of these nematodes accelerates the decomposition process and makes minerals and nutrients accessible to growing plant roots.
Thirdly, nematodes are valuable biological agents of pest control. Predatory nematodes regulate populations of other organisms in soil as they feed on organisms such as protozoa, insects, and other nematode species. As a result, nematodes moderate the population of other nematodes, and studies have shown that nematodes such as the Steinernematidae and Heterorhabditidae can kill soil-based insect pests within 48 hours. Finally, nematodes have become key biological indicators of soil health. The diversity and richness of nematodes communities are particularly insightful as they act as proxies to reveal information on the levels of nutrients, fungal availability, and bacteria,

9.1 Introduction

Phytochemicals are the individual chemicals from which the plants are made. Phytochemical is simply a word that means plant chemicals. Plants have the ability to synthesize mixtures of structurally diverse bioactive compounds with multiple and mutually potential therapeutic effects. The plants have the capacity of manufacturing the secondary products. Phytochemicals with antioxidant properties tend to be brightly colored because they contain chromophores, ie, a series of alternating single-bonded and double-bonded carbons. Isoprene is often the building block of such units. The darkest green vegetables contain the most chlorophyll, and vegetables with the most chlorophyll require the most antioxidants. Green will mask the other colors, when other-colored antioxidant phytochemicals are present. Hundreds of phytochemicals are currently being studied. Many are believed to have a major positive impact on human health (Duke and Sternberg, 2005). Important plant secondary metabolites have been isolated over a period of time from natural sources. The phytochemical may belong to the following categories : Terpenoids, Phenolic compounds, Alkaloids, Glycosides, Carbohydrates, Lipids, Proteins, Nucleic acids, etc. Some of the phytochemicals from the plants are listed in Table 9.1 and structures of some of them are given in Fig.9.1.

Jay et al., (1995) and Joerger et al., (2003) have written the role of bacteriocins as an alternate to antibiotics. Bacteria produce bacteriocins which are proteinaceous in nature or peptidic toxins. These inhibit the growth of similar or closely related bacterial strain(s). There are different types of bacteriocins which are classified based on the producing strain, common resistance mechanisms and mechanism of killing. Ahmad et al., (2013) have isolated antifungal compound for food preservation. Martin et al., (2018) and Batish et al., (1997) found antibacterial compounds from fungus. Mahboubi et al., (2019) studied the potential of Zataria in IBS. There are bacteriocins from gram-positive bacteria known as the colicins, the microcins and the bacteriocins from Archaea (Cascales et al., 2007). The bacteriocins from E. coli are called colicins (formerly called ‘colicines,’ meaning ‘coli killers’). These have been studied widely. Earlier called colicin V and is now known as microcin V. It is very small and is produced and secreted in a different manner than the classic colicins. Adrienne et al., (2016) have studied the colicin resistance.

Hybrid vigour is used as a synonymous of heterosis. In 1910, the term heterosis was first used by Shull who defined this phenomenon as the stimulus of heterozygous, and in his word, it has been the “interpretation of increased vigour, size, fruitfulness, speed of development, resistance to insect-pests and diseases or to the climatic rigors of any kind manifested by the out breeding organism as compared with corresponding inbreds as a specific result of the unlikeliness in the constitution of uniting parental gametes”. This definition is often interpreted as not implying a genetic basis for heterosis, because the definition basically describes the phenotypes that result from the crossing of two different inbred lines. Generally, heterosis is manifested as an increase in vigour, size, growth rate, yield, or some other characteristics but in some cases, the hybrid may be inferior to the weaker parent. This also represents as heterosis (average heterosis), and if heterosis is estimated over the superior parent, such an estimate is sometimes referred to as heterobeltiosis, hence, authors feel “heterosis refers a biological phenomenon in which the F₁ population obtained by crossing of the two genetically dissimilar gametes or individual shows increased or decreased vigour over better parent or over the mid-parental value. Earlier, Power (1944)also suggested that the term heterosis should be used only when the hybrid is either superior or inferior to both the parents. Other situation should be regarded as partial or complete dominance. It can be easily explained with the help of Table 5.1.

Tillage is a mechanical manipulation of soil to provide favourable condition for crop production. Soil tillage consists of breaking the compact surface of earth to a certain depth and to loosen the soil mass, so as to enable the roots of the crops to penetrate and spread into the soil. A good seedbed is generally considered to imply finer particles and greater firmness in the vicinity of seeds. The depth up to which tillage operations disturb the soil can classify the operation as shallow, medium or deep. The depth of tillage depends on the crop and soil characteristics and also on the source of power or energy available. The optimum seedbed preparation for raising upland crops, involves the many unit operations. Strength of soil is affected by soil moisture content and can be represented in terms of cone index. Compacted soil has more cone index than the loose soils. Movement of machine in the field causes soil compaction. Sometimes it forms hard pan which is to be broken by the tillage operations to enhance root growth and penetration and infiltration of excess water.

3.1 Damping-off Disease of Seedlings

The disease is quite common in nurseries or seedbeds all over the world. It is virtually a serious threat to almost all the nursery crops of vegetables and other crops including tomato, chillies, cauliflower, cabbage, brinjal, cucurbits, tobacco and a number of other crops. The economic importance of the disease is more because it takes the toll of precious seedlings in the very initial stages of the crop cultivation. The seed can become infected with a fungus which may cause darkening and softening of the seed leading to its decay. Similarly, seedlings may also be infected while sprouting or even after emergence. The disease is more serious in heavy soils with poor drainage. Abundant soil moisture with 90-100% humidity and temperature around 200C is favourable for the disease.

Phytochemicals are the individual chemicals from which the plants are made. Phytochemical is simply a word that means plant chemicals. Plants have the ability to synthesize mixtures of structurally diverse bioactive compounds with multiple and mutually potential therapeutic effects. The plants have the capacity of manufacturing the secondary products. Phytochemicals with antioxidant properties tend to be brightly colored because they contain chromophores, ie, a series of alternating single-bonded and double-bonded carbons. Isoprene is often the building block of such units. The darkest green vegetables contain the most chlorophyll, and vegetables with the most chlorophyll require the most antioxidants.

Introduction 

In the thirst of modernization and industrialization man has contributed pollution to the life and ecology of plants, animals and microbes. Increased demand for food and fiber has lead to the chemicalization of agriculture we have reached to such a stage that modern agriculture is dependent on high yielding varieties, which can only be grown under the influence of fertilizers and pesticides. Pesticides are the man made chemicals which are being used to produce enough cheap food. In India, 90,000 MT of technical grade pesticides are used annually to control pests and plant diseases. The pesticides are classified as insecticides, fungicides, weedicides, herbicides, nematodicides and rodenticides; of which insecticides constitutes 77% of the total pesticides used in different agricultural and animal husbandry practices and in public health operations.