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Definitions

        Toxicology: Knowledge (or science) of poisons, including their chemical properties, identification, biological effects, and the treatment of conditions they cause.

        Poison: Any solid, liquid, or gas that, when introduced into or applied to the body, can interfere with the life processes of cells of the organism - by its own inherent chemical properties - without acting mechanically and regardless of temperature.

Definitions
 
    •    Toxicology: Knowledge (or science) of poisons, including their chemical properties, identification, biological effects, and the treatment of conditions they cause.

    •    Poison: Any solid, liquid, or gas that, when introduced into or applied to the body, can interfere with the life processes of cells of the organism - by its own inherent chemical properties - without acting mechanically and regardless of temperature.

    •    Poison = Toxicant: The term poison is now used less often. Reason: Historical application of the term (malicious) vs. a compound used as a feed additive, agricultural, or other chemical - manufactured to fulfill a perceived human need.

We may study the nutrient metabolism in a better way as explained in the following summarized form in Table 1.

Historical Development of Soil Science/Agriculture

Francis Bacon (1561-1624 A.D.): Found the water as nutrient of plants.

Van Helmont (1577-1644): Give the ideas about the role of soil as a simple source of water and minerals for the plants.

Section-A : Write True / False

Q.1 The moment generating function (m.g.f) of a random variable X (about origin having the probability function f (x) is defned as

Abstract

Rural women play a vital role in farming system operations and contribute substantially in the physical aspect of farming, livestock management, postharvest and allied activities. Around 43% of the agricultural labour force of developing countries is composed of women dependency. India has achieved self sufficiency in agricultural production, but a considerable amount of production gets spoiled in every year due to inadequate post-harvest management, processing, infrastructure and skill. To uplift the livelihood and economic conditions of the rural women there is an urgent need to impart trainings for skill development regarding the value addition of horticultural crops. This offers tremendous opportunities for women occupation but also inculcate entrepreneurial characteristics in them. Trainings and skill development are useful for rural women as they can add more value to the seasonal fruits and vegetables and generate varieties of products namely Pickle, Murabbaa, Chutney, Jam, Sharbat etc. These efforts enhance their family income by around 30-40 thousands per annum as they fetch more prices of raw produce after processing. Moreover during peak production times glut only promote produce and profit loss. Instead of direct marketing of their produce they can do value addition of their produce and then sell them in market, it not only increases the value of their products but the prices also enhance by many folds. After giving training to rural women, they are motivated to go for self marketing of their produce at domestic and village level. Similar way these trainings can transform the life style and income level of farming families comprehensively.

Introduction 
Augmented energy demand as well as impacts of employment of fossil coals on human health and environment, stresses and imposes the need to lessen the use of conventional fuels or replace them. Equally, global warming has stretched to a distressing level due to many diverse anthropogenic actions leading to increased pollution. The alternate energy sources are desirable that might be the conspicuous and sustainable approach of enabling environmental remediation, besides meeting the global energy call (Grosser et al 2016, Kanchanasutha et al 2016). A potential solution is generation of Biofuels, either conventional biofuels produced from agricultural crops or advanced biofuels produced from wastes, inedible crops or forestry products (Sreedevi Sarsan et al 2021). Advanced biofuels production especially by the utilization of agricultural and animal wastes using new technologies and processes are gaining increased interest among researchers and general public all over the world. Food waste, municipal trash, animal waste and other wastes can all be utilised as feedstocks to create biogas, a clean and sustainable energy source and thus may be the ideal replacement for traditional energy sources. The raw biomass may be converted into fuel products like biogas by briquetting, gasification, and anaerobic digestion, among other processes (Deepanraj et al 2015). In comparison to landfills, incinerations, and composting processes, anaerobic digestion (AD) is suggested as an inexpensive and environmentally benign technique for the generation of renewable energy (Van Forest et al 2012; Nishio et al 2007; Capson-Tojo et al 2016; Xu, F et al 2018; Cha, M et al 2020). The production of energy-rich biogas and alleviation of issues related to the removal of organic waste are all achieved by anaerobic digestion (AD) of organic solids (Sonakya et al 2001). This is since AD is a highly energy-efficient and ecologically benign technique. In an atmosphere devoid of oxygen, the AD system uses anaerobic microbes to transform the naturally occurring substances in the biomass into biogas. The primary byproduct of AD, biogas, has a methane content of roughly 50-70% by volume and 30- 40% atmospheric carbon dioxide (CO2) when feedstocks are digested under anaerobic circumstances, with small levels of hydrogen sulphide (H2S) (0.1-3% v/v), humidity, and other trace pollutants also present (Sahota et al. 2018). The generation of biogas is known to be influenced by factors such as waste types, pretreatment procedures, the microorganisms or enzymes added, operation circumstances and design of the digestors (Mao et al 2015).

Introduction

Spectral signature: A spectral signature is the unique pattern of reflection and emission of a target at different wavelengths. This difference helps to classify remote sensing images based on the spectral signatures of different objects.

Electromagnetic (EM) spectrum: The EM spectrum is the range of all types of EM radiation. Some examples are visible light from a lamp, radio waves from a radio station, microwaves, infrared light, ultraviolet light, X-rays, and gamma rays.

Spectral response patterns: A spectral response pattern is the amount of energy that an object reflects or emits at different wavelengths. It shows how the object interacts with the EM radiation.

Generation system of seed multiplication is nothing but the production of a particular class of seed from specific class of seed up to certified seed stage. The choice of a proper seed multiplication model is the key to further success of a seed programme. This basically depends upon,

• The rate of genetic deterioration
• Seed multiplication ratio
• Total seed demand (Seed replacement rate)

ABSTRACT

Of the total production of the crop yield, only 63 per cent is available for human consumption. The remaining is lost in more or less equal proportions to weeds, pests and diseases. Prior to genetic engineering, the exchange of DNA material was possible only between individual organisms of the same species. In the field of agriculture for instance, farmers have continuously modified naturally occurring species through seed selection and controlled breeding. With the advent of the recombinant DNA technology, it has however been possible to identify specific genes associated with desirable traits in one organism and transfer those genes within and beyond the boundaries of species into other organisms.

1. Genes for herbicide resistance

Modern agriculture has developed a range of effective herbicides to tackle the effects of weeds on crop yield. Some of the most useful of these are broad-spectrum herbicides because they are active against a wide range of weeds. However, these can only be used at times when the crop is not itself vulnerable to herbicide action. The development of herbicide-resistant crops therefore offers the opportunity to spray crops at the most effective time to kill weed species without damaging the crop plants. By definition, herbicides are much more toxic to plants than to animals. Therefore, it is not surprising that they generally affect ‘plant-specific’ biological processes. The herbicidal activity of many herbicides has been found to result from the specific inhibition of a single enzyme/protein. The following are four distinct strategies for engineering herbicide resistance: i. Overexpression of the target protein, ii. Mutation of the target protein, iii. Detoxification of the herbicide, using a single gene from a foreign source and iv. Enhanced plant detoxification.

Random Mating

Random mating occurs when each female gamete has an equal chance of being fertilized by any male gamete of the same plant or with any other plant of the population and, furthermore, there is an equal chance for seed production. It is not possible to achieve true random mating in plant breeding because selection is involved. Consequently, it is more realistic to describe the system of mating as random mating with selection. Whereas true random mating does not change gene frequencies, existing variability in the population or genetic correlation between close relatives, random mating with selection changes gene frequencies and the mean of the population, with little or no effect on homozygosity, population variance, or genetic correlation between close relatives in a large population.

Acid soils are found in India in about 93 million hectares ( Table 1) and they occur in the Himalayan region, the great Indo-Gangetic and Brahmaputra plains, peninsular plateau and uplands and the coastal plains including island eco-systems under varying environmental conditions of landscape, geology, climate and vegetation. Conditions which are conducive for the formation of acid soils, such as high rainfall coupled with high temperature encouraging intense weathering and loss of alkali and alkaline earth metals with a simultaneous accumulation of iron and aluminium hydroxy compounds or the formation of free acidic substances in the humid forest foot hill regions, exist in some region or other in almost all the states in India.  A soil with pH less than 7.0 is deemed as an acid soil (Soil Survey Staff,1951). However, for characterization and classification, acid soils may be defined as those having pH less than 5.5 in 1:1 water extract (Soil Survey Staff, 1999).

Horticulture deals with the art, science, business and technology of cultivation and management of horticultural plants. The word Horticulture is derived from two Latin words viz. ‘Hortus’ (means garden) and ‘Culture’ (means growing). Horticulture is an aesthetic science that deals with cultivation of fruit, vegetable, spice, plantation, medicinal, aromatic and flower crops. There is a vast therapeutic use of horticulture wherein gardening and aroma therapy are used to deal with new age maladies like depression and various addictions.

In ancient times, huge gardening spaces to grow large number of fruits, vegetables and flowers were available and these areas were demarcated with the help of high walls. This enclosed area was referred to as garden. This led to the term garden culture. The land area is decreasing due to industrialization and population growth, at the same time, there is a drastic increase in demand for horticultural produce. To meet the increased demand for horticultural produce and to cope up with the space constraints, multitier cropping systems, vertical gardening and other intensive cultivation practices are being resorted to. Hence, horticulture may also be described as the “Practice of growing and manipulating plants in a relatively intensive manner”.

Presently, fruits, vegetables, flowers and ornamentals are grown not only within the home premises, but also in large quantities on a commercial scale. In other words, many horticultural crops throughout the world are grown primarily as business enterprises. Thus, horticulture has two aspects in general i.e., the amateur and the professional. In addition, with the establishment of horticultural experiment stations as an integral part of colleges and universities, comparatively a large amount of scientific information on the behaviour and cultivation of horticultural plants and products is freely available. This information or literature, constitutes the science of horticulture, and the application of this scientific information constitutes the “Technology of Horticulture.” Thus, present day horticulture may be defined as the science and technology of production, processing and merchandising of fruits, vegetables, flowers and ornamentals where each crop has its own science and technology. Consequently, horticulture may appear differently to different people. To a teacher, professor, research scientist, extension official and landscape architect, it is an applied science and a profession, while to a commercial producer, wholesaler, a retailer of horticultural products, or to the manufacturers or seller of horticultural products, it is a business. It is also a fascinating hobby for connoisscur.

The narrow sense heritability estimates were high for days to first flowering, plant height at first flowering, number of leaves at first flowering, plant height at maturity, productive tillers per plant, boot leaf area, 100 grain weight, grain length and grain L/B ratio. These characters may be controlled by additive genetic variance. This indicated that the individual genotype can be evaluated readily from their phenotypic expression. Simple selection would more effective in the sets of materials exhibiting greater additive genetic variability and desirable mean performance. Thus, it merit selection in the next generation. On the other hand, the remaining traits may largely be controlled by non-additive genetic variance or the number of genes controlling these traits may be more, or these traits may largely be influenced by a large number of modifiers or might be largely influenced by environment. As the effects of the environmental variance were generally low, the observed low heritability for the above traits might be due other factors other than environment. These traits are hard to improve by selection. It necessitates progeny testing.

The relative magnitude of different gene effects and an understanding of the mode of inheritance of complex quantitative traits have a direct bearing on the method of hybridization and selection which should be adopted in a specific breeding programme. Useful biometrical methods have been developed by the Birmingham group of scientists, to analyse the genetic architecture in organisms, through the use of first and second degree statistics obtainable from the true breeding inbreds, their first generation crosses and the different types of segregating progenies (Mather, 1949; Hayman, 1958; Gamble, 1962; Mather and Jinks, 1971). Since then this method has been widely used in the genetic analysis of various crops.

Generation of new genetic variability through recombination breeding followed by appropriate selection procedure is one of the key factor for crop improvement. Gain in selection is restricted by correlated response of agronomically desirable as well as undesirable characters. There is a host of examples in various crop species where genes for desirable agronomic traits have been found to be closely linked with those governing undesirable characters (Murthy, 1971; Clegg et al., 1972). Such close linkages delay the realization of the full recombination potential in many crops. The biparental mating or the disruptive mating scheme, finds its importance in the improvement of autgamous speice,s because it increases the probabilities of obtaining useful recombinants as compared to selection without intermating (Hanson, 1959; Jensen, 1970).

In contrast to classical pedigree breeding, random mating population could produce large amounts of variability. This variability can be maintained in the population by the use of recurrent intermating, while the population is improved by selection. According to the standard breeding methodology in self-pollinated crops selection for quantitative characters are generally taken up in early segregating generations. For characters like yield, selection is continued till the material becomes homozygous. Such characters are controlled by large number of genes and a very large population has to be raised to make selection effective. Since most plant breeders could never grow the theoretically required size of population, the recombination is highly restricted. It is likely that many of the valuable genes may be practically lost in the process of advancing the material by continued selfing the generations. Andrus (1963) suggested crossing of selected sibs in early generation for reassembling the genes capable of functioning in a balanced polygenic system.

Eswaran (2007) made genetic analysis of six parents and their 30 hybrids of Okra with the method of analysis proposed by Hayman (1954b). He estimated the various genetic parameters viz., _D?, _F?, H?₁, H?² and Ê as well as the various genetic ratio. The results are presented in Tables 69 and 70.

The estimates of _D? were significant for seven out of ten characters studied. This indicated that the component of variation due to additive genetic variance was important for days to seedling emergence, number of first fruiting node, height of first fruiting node, plant height, days to first picking, number of fruits per plant and fruit weight. These characters could be improved by resorting to simple selection. The estimates of H? ₁and H? ₂were positive and significant for almost all the characters studied. It indicated that there were unequal frequency of alleles i.e., u ¹ v at all the loci, in this context, ‘u’ refers to the frequency of alleles which increase the mean expression of the character and are situated at loci which exhibited dominance. On the other hand, ‘v’ corresponds to the frequency of alleles at loci that decreases the expression of the character. Further proof for the unequal distribution of the alleles over loci was obtained

Among the different biometrical methods available, triple test cross analysis is one of the most efficient designs currently available for investigating the genetic structure of populations. It provides a test of epistasis and in its absence it gives independent and equally precise estimates of additive and dominance genetic components (Mather and Jinks, 1982).

11.1. Statistical analysis

Triple test cross

Jinks and Perkins (1970) method was applied to detect epistasis and estimate additive and dominance components of genetic variance.

Abstract

Genetic analysis of yield and yield components in tomato (Lycopersicon esculentum Mill.) was worked out by using half diallel mating design. The good general combiners observed were Solan Vajr, FT-5 and UHF-265 for plant height; UHF-107 and UHF-260 for days to first picking; Solan Vajr for number of fruits per cluster; FT-5, EC-191536 and UHF-120 for average fruit weight; Solan Vajr, UHF-265 and FT-5 for harvest duration and FT-5 and Solan Vajr for marketable yield per plant. The best three specific combiners for marketable yield per plant were EC-191536 x Solan Vajr, BL-342-1 x FT-5 and UHF-107 x EC-191536. Hayman’s approach revealed non-allelic interaction in the expression of number of fruits per cluster, number of fruits per plant and marketable yield per plant. Preponderance of non-additive gene action was observed with dominance towards tallness, delayed first picking, more fruits per cluster, longer harvest duration and higher marketable yield, while involvement of complimentary epistasis was indicated in the inheritance of average fruit weight and number of fruits per plant.