eChapters

1.1. WEATHER AND TILLAGE

Weather : A state or condition of the atmosphere at a given place and at a given instant of time'

Climate : The generalized weather or summation of weather conditions over a given region during comparatively longer period

Meteorology : Greek word “Meteoro” means 'above the earth's surface' (atmosphere) and “logy” means “indicating science”. Branch of science dealing with that of atmosphere is known as meteorology

Agricultural meterology : Branch of applied meteorology or a branch of agriculture as it deals with agriculture

Coordinates of India : 8^o N and 37°N latitude; 68°E and 98°E longitude

Coordinates of Tamilnadu: 08°05' N and 13°35' N latitude; 76°15' E and 80°20' E longitude

Hydrosphere - water portion of the earth

Lithosphere - solid portion of the earth

Atmosphere - gaseous portion of the earth

Atmosphere : It is the colourless, odourless and tasteless physical mixture of gasses, which surrounds earth on all

Phytonematodes spend much of their lives inside or in contact with host tissue, and molecular interactions constantly occur and shape the outcome of parasitism.Eggs of these parasites generally hatch in the soil, and the juveniles must locate and infect an appropriate host before their stored energy is exhausted Components of host exudate are evaluated by the nematode and direct its migration to its infection site.Host plants recognize approaching nematodes before physical contact through molecules released by the nematodes and launch a defense response In turn, nematodes deploy numerous mechanisms to counteract plant defenses. A review by Shahid Siddique et al., (2022) focused on these early stages of the interaction between plants and nematodes and discussed how nematodes perceive and find suitable hosts, how plants perceive and mount a defense response against the approaching parasites, and how nematodes fight back against host defenses.

Summary

Climate change can affect the quantitative and qualitative status of water resources by altering hydrological cycles, systems and through changes of water quality via chemical and biological contamination. Changes in these variables lead to impacts on all the socio-economic and environmental goods and services that depend on these variables directly or indirectly including water supply, damage to ecosystems, water dependent food production. The most dominant climate drivers for water quantity or water availability are precipitation, run-off and river flows, floods, droughts, snows, glaciers, sea level rise etc. The observed climate change related impacts on world’s water resources/water quantity include increased precipitation at high latitudes and temperate areas and decreasing trends at low latitudes. The annual run-off in some regions may experience increased run-off, such as in high latitudes and large parts of the USA, whereas there has been a decrease in run-off such as parts of West Africa, southern Europe and southernmost of South America. Floods have been the most reported natural disaster events in Africa, Asia and Europe than all other natural disasters and in case of Bangladesh, six extreme floods have occurred in the last two decades. More intense droughts have been reported from Australia, semi-arid and semi-humid regions, western USA and southern Canada, the Sahel. Precipitation is projected to increase at mid- and high latitudes, in the tropics, whereas precipitation is projected to decrease over many sub-tropical areas (North Africa, northern Sahara), tropical Central American (Caribbean) and the Mediterranean. In areas where evaporation rates are expected to increase it would lead to reduced river and stream run-off. In contrast, areas receiving higher precipitation would likely have higher lake and river levels and may experience floods. The annual stream flow in the Murray-Darling basin (Australia) is projected to fall by 10-25% by 2050 and 16-48% by 2100 which would have severe consequences on irrigated agriculture in the region. Rivers depending on the Himalayan glaciers such as the Indus, Ganges, Brahmaputra, Syr Darya and Amu Darya could face water shortages or river run-off due to retreat of glaciers, and this would cause dramatic impact on drinking water supplies, biodiversity, hydropower, industry, agriculture and ecosystems on which about 2.4 billion people in Asia depends. Globally, ground water is the source of one third of all freshwater withdrawals, supplying an estimated 36%, 42% and 27% of the water used for domestic, agricultural and industrial purposes, respectively. The demand for groundwater is likely to increase due to global increase of water use for irrigation and a decline in surface water quality and reduced summer flows in snow-dominated basins. It is projected that climate change (drought, floods) will affect groundwater recharge rates (e.g. floods would increase recharge, drought would decrease recharge).

Q. 1 When flow parameters change with time but remain constant with space the flow is called as:-
(A) Unsteady uniform flow       (B) Steady uniform flow
(C) Steady non-uniform flow   (D) Unsteady non-uniform flow

No country is self-sufficient in plant genetic resources, and until recently this was thought to be sufficient to ensure the free flow of germplasm among nations. However, the concepts of ownership, sovereignty and intellectual property rights (IPR) have increasingly been invoked of late in discussions of how best to conserve and use plant genetic resources. This has resulted from the growing realization that germplasm has real economic value. At the same time, awareness has grown that the repercussions of overexploitation of natural resources, of the extinction of species and the disappearance of crop landraces, of environmental damage and of habitat destruction can be global, transcending national boundaries and short-term financial considerations (Anon. 1995). Therefore important international agreements/legislations on plant genetic resources management have been enacted from time to time. The important ones are as follows :

There is widespread belief now that forests can be used to reduce the costs of slowing climate change. While the role of forests in the global carbon cycle has long been acknowledged, recent discussions within the context of the United Nations Framework Convention on Climate Change, as well as efforts to write climate change legislation in the United States, have emphasized the role forests might play. The most recent policy efforts have focused on near-term actions to reduce deforestation in tropical countries. The rationale for considering forests at all in the policy mix stems partly from the physical components of the issue. The world’s forest estate is exceedingly large:

9.1. Introduction

Soil biology is a branch of science that studies the soil inhabiting organisms in relation to their ecology, functions, behaviour and impact on various soil processes and plant growth. Soil fertility is directly dependant on humus content as well as the presence of microorganisms in soil, although surface soil does not contain more than 0.5% by weight of living organisms. However, such a small portion of soil constituent as compared to other organic and inorganic constituents plays a significant and major role in transformation of plant nutrients from their unavailable to available form from organic wastes, soils and fertilizers. They have a direct role in improving soil tilth, providing an appropriate environment for root growth, decomposing organic residues to form humus and in turn releasing nutrients for plants use, releasing many plant growth promoters, fixing inert atmospheric nitrogen in plant usable forms and they promote many other important processes without which plants cannot survive. Absence of living organisms in soil leads to its infertility. An understanding of microbial processes in soil environment, keeping in view of soil nutrient status, carbon sequestration, soil health and quality, overall sustainability in agriculture and also global warming in respect of greenhouse gas emissions (nitrous oxide and methane) through agricultural practices, is very important in regulating nutrient release at different plant growth stages. If we are in a state to understand how various biological processes influence various changes in soil environment or in the opposite way that how different soil conditions alter the soil biota in number as well as in their functions and diversity, it is easier to implement soil management practices that promote to gain more benefits.

Microorganisms are ubiquitous in nature. Possessing a diverse habitat, they are found everywhere in soil, air and water at a varied temperature and pH. One may find the highest genetic diversity of life within the domain of microorganisms. But unfortunately very few are known to us, so far only 1% of the microbial species on the earth are culturable. However, it is believed that soil of one gram may contain hundreds of millions to billions of microbes which may represent several thousand microbial species. In respect of the population, bacteria top the list followed by actinomycetes, fungi, algae and protozoa in accordance with a decreasing numerical order. Out of three important soil fertility components viz. physical, chemical and biological; the biological component is least understood due to its wide complexity.

India situated between the latitude of 8°04/ and 37°06/N and longitudes of 68°07 to 97°25, has a geographical area of 329 Mha. Physiographicaly, it can be divided into the three broad regions, viz., Peninsula (a triangular Plateau in the Deccan and South of the Vindhyas), Mountain region of the Himalalayas (Extra-Penninsula), and the Indo-Gangetic Plain separating the these two regions.

Geologically, a great part of the Penninsula is occupied by the gneiss, schists and other rocks of diverse nature. Red soils (Alfisols) generally predominate in this region. The western and central parts predominate in basaltic rock having Black cotton soils of different thickness (Vertisols Inceptisols). The mountain region shows the development of marine sediments of all ages especially in north of the Himalayas.

The vast Indo-Gangetic and other plains of Pleistocene origin are composed of alluvium of the great river systems flowing in this region. The alluvial soils of this region depend on the age of alluvia and degree of development.

Climatically, India shows three distinct seasons, viz. i) cool and mainly dry winters from November to February, ii) hot and mainly dry summers from March to June and iii) monsoon rainy season from mid June to September. Rainfall is received during June to September (from the south-west monsoon) and during December to February (from the north-eastern winds). The Western Ghats and the eastern Himalayas ranges receive maximum rainfall because of their alignment across the summer monsoon winds. The Indo-Gangetic plains receive moderate rainfall; Rajasthan receives little rainfall as the Aravallies lie along the path of the moisture- bearing winds.

Abstract

Agriculture continues to be the most important sector of the Indian economy and agriculture is a  more or less a compulsion for livelihood of millions of farmers. Land and water resources have almost reached their limits, price of commodities are fluctuating almost every day, profits are negligible for most of the marginal and small farmers and most of all getting information is cumbersome. In present day agriculture, soft resources like knowledge and skills are as important as hard resources like inputs, and sometimes more important. But estimates indicate that 60 per cent of farmers do not access any source of information for advanced agricultural technologies resulting in huge adoption gap. The requirement of field level extension personnel is estimated to be about 1.3 -1.5 million against the present availability of about 0.1 million personnel. The mobile phone comes into the picture here.

The seed drills and planters developed and manufactured in advanced countries are designed to meet the requirements of farmers for the different crops and agro-climatic conditions. These machines are capable of operating at high working speed, cover the large area per unit time and provide the desired plant emergence and stand in the fields. The machines are available to handle the seeds of cereals, pulses, oil seeds and other crops widely grown in the developed countries. In developing countries even though these machines can be made available but they are beyond the reach of small farmers. The level of mechanization of sowing and planting is at a very low level.

Crop productivity is largely affected by the several factors; however, biotic stress factor is one of the major concerns. Horticultural crop productivity is low in India as compared to other countries for many reasons including pest problems. Plant parasitic nematodes is one of the potential threat for cultivation of some important crops- root knot and reniform nematodes in vegetables; burrowing nematodes in banana, spices and plantation crops; citrus nematode in citrus; cyst nematodes in potato, foliar and lesion nematodes in flowers etc.

6.1 Nematodes as Biological Models
A model organism can be a non-human species (e.g., microbe, plant, or animal) with extensive genomic research data. These organisms are used to study and understand specific biological phenomena, with the expectation that discoveries made in these models will provide new insights into “big biological questions” (Semprucci et al., 2025). Model organisms are widely employed to explore potential causes and treatments for human diseases when direct experimentation on humans is unfeasible or ethically problematic. This approach is supported by the common descent of all living organisms, as well as the conservation of metabolic and developmental pathways and genetic material over the course of evolution. The use of model organisms is not confined to biomedical research. Significant advancements in developmental biology, eco-toxicology, fertilization processes, speciation, symbiosis, and sexual selection have been achieved using these models. Furthermore, emerging animal models—species with less neurological complexity than those protected by legislation—are increasingly recognized as a valid application of the Three Rs principle (Replacement, Reduction, and Refinement). To support this approach, databases of invertebrate species currently used or with potential applications in biomedical research are continually being developed and updated.
Nematodes, particularly Caenorhabditis elegans, are widely used as model organisms in biological research due to their simplicity, ease of study and shared biological processes with other animals, including humans. C. elegans, a small, free-living nematode, has a short life cycle, a known number of cells and a well-mapped genome, making it an ideal system for studying developmental biology, genetics and other aspects of animal biology.

Worldwide, almost 90% of the human food supply is provided by only 15 crop species and eight livestock species. The eight livestock species useful to man include cattle, buffalo, sheep, goat, pig, poultry, camel and horses. All or some of these species provide milk, meat, skin, fiber and manure for use of mankind. Whereas, milk and meat are important component of human food supply, skin, fiber and manure are also useful in different manner. Goats are important food-producing animals especially in tropical and subtropical regions. Goats are the most adaptable and geographically wide spread livestock species.

A breed of livestock is a group of animals that, through selection and breeding, have distinguishable characteristics and resemble one another and pass those traits uniformly to their offspring. Or A breed is defined as a group of animals that has been selected by humans to possess a set of inherited characteristics that distinguishes it from other animals within the same species. A cluster of domestic animals of a species where individuals are homogeneous in certain distinguishable characters which differ from one to the other group of animals constitute the breeds. Breeds are primarily distinguished by visual characteristics: color pattern, polled or horned condition, or extreme differences in form and shape. Breed is indicative of the perception of the breeders and the livestock industry which decides when a group of individuals constitutes a “breed”. Livestock breeds have evolved over time through genetic changes that are both natural and selected by man.

Primarily breeds have been developed to provide increased production of meat, milk and/or wool, pashmina within a certain environmental area. This breed development is a process of continuous selection over a number of generations so as to stabilize the characters in the animals for the selected traits. The distinguishable characters are quite often color markings, size, and shape, hair pattern which may have little economic significance in terms of meat, wool or pashmina production. Breed development may have begun soon after animals were first domesticated. Breed is a group of animals related by descent and similar in most characteristics like general appearance, features, size, configuration, etc. In most cases, selection has been practiced for many generations in order to fix certain characteristics in the breed. The goat breeds have since long been described primarily in terms of physical conformation (chiefly, ear, nose, face and horn), body coat/colour characteristics and body measurements with subtle reference to production traits. Today there are more than 300 breeds of goats, and they live in climates ranging from high altitude mountains to deserts. Some breeds are known by the same name in different places, but are phenotypically different from one place to another. Conversely, there are breeds that look alike but have different names in different places.

6.1 Introduction

In order to increase the production and productivity of crops, provision of irrigation system is highly essential. A project that makes use of weir or a barrage for providing irrigation to fields is called as direct irrigation system. On the other hand, a storage irrigation system makes use of storage reservoir by construction of dams. In order to provide irrigation by both the schemes, it is necessary to have a network of canal systems. A canal is an artificial channel, generally trapezoidal in shape constructed on the ground to carry water to the fields. The canal systems that provide water to the fields include main canals, branch canals, distributaries, minors and watercourses. It is imperative to design the canal systems properly for a certain realistic value of peak discharge that must pass through them so as to provide sufficient irrigation to the command areas. The flow irrigation that provides irrigation water to the fields may be of two types i.e. Inundation irrigation and Perennial irrigation.

From an ecological perspective all organisms are part of nature, irrespective of what they do. To a farmer, all organisms that reduce the yields of their crops are considered pests, diseases or weeds. Insects, birds or other animals are also pests whenever they cause damage to crops or stored produce. Fungi, bacteria and viruses are also recognized as disease causing organisms when they lead to conditions that interrupt or modify the vital functions of growing plants or stored produce. All unwanted plants that grow within crops and compete with them for nutrients, water and sunlight are considered weeds. Such plants can also be hosts for pests and diseases.Presence of these organisms in crop fields is not a problem until their numbers increase beyond a level where they attack, and cause substantial reductionin field crop yields or quality of harvested and stored produce.

The organic approach to plant pest, plant disease and weed management makes reference to the four principles of organic agriculture: the principle of health, the principle of ecology, the principle of fairness, and the principle of care. Generally, organic farmers aim at sustaining and enhancing the health of their soils, plants, animals, humankind and—in the widest sense—the planet. The health of individuals and communities cannot be separated fromthe health of ecosystems. Therefore, by providing healthy soils and a diversified natural environment, farmers are able to produce healthy crops that foster the health of animals and people.

Healthy plants are also able to resist and tolerate physiological disruption and damage from disease-causing organisms and pests. Thus, organic farmers aim at optimizing the growing conditions for their crops to make them strong and competitive. At the same time they encourage natural control mechanisms to prevent pests, diseases and weeds to develop in a way that they cannot damage the crops. They, therefore, give priority to preventive measures to prevent and limit the spread of infections, instead of relying on direct control measures. Direct control measures are mainly applied when pathogens have already developed.

Key Facts
        
Agricultural food
    
·    There are multiple pathways through which climate-related factors may impact food contamination and food safety, food quality, foodborne diseases including changes in temperature and precipitation patterns, increased frequency and intensity of extreme weather events, ocean warming and acidification and changes in the transport pathways of complex contaminants.
    
·    All or most foodborne pathogens and their associated diseases are linked to changing environmental conditions, the notable of which are campylobacteriosis, salmonellosis and vibriosis.
    
·    An estimated 30% of reported cases of salmonellosis across much of continental Europe have been attributed to warm temperatures, especially when they exceed a threshold of 6°C above average. Likewise both in Australia and Canada a positive correlation was found between increasing temperature and incidence of salmonellosis.
    
·    Zoonosis such as Rift Valley Fever (RVF), West Nile Fever, tick-borne diseases and non-zoonotic animal diseases such as Blue tongue, African horse sickness, African swine fever are examples of animal diseases whose distribution is expected to be strongly influenced by climate change and variability.
    
·    Mycotoxin is a toxic secondary metabolite produced by filamentous fungi, commonly known as moulds and may contaminate agricultural commodities (food) by growing on them both before and after harvest, whenever the humidity and temperature are permissive. The most prominent mycotoxins are aflatoxins, deoxynivalenol, zearalenone, ochratoxin-A, fumonisin, and patulin.
    
·    The humans ingestion of mycotoxins occur through consumption of the mycotoxin contaminated plant-based foods, such as grains, maize, barley, rice, coffee, nuts and their residues, and metabolites in animal-derived foods, for example aflatoxin M1 (AFM1) in milk and meat products. In addition, mycotoxins may occur in beer and wine.

1. Introduction

Cherry is the common name of several Prunus species that include sweet cherry (P. avium), tart or sour cherry (P. cerasus), Duke cherry (hybrids between P. avium and P. cerasus). Sweet cherries are believed to have originated from the area between the Black and Caspian seas of Asia Minor. Birds probably carried the seed to Europe prior to human civilization. Cultivation was probably started by the Greeks and continued by the Romans. Its distribution and naturalization have proved extensive, for it is now found wild in areas as widely spaced as northern India, the southern plains of Europe and even on isolated islands such as Madeira. Climatic conditions are the most important limitations on cherry production. Being a deciduous tree, it needs a period of dormancy, which is initiated in temperate regions mainly by a fall in average temperatures in late autumn (Mir et al., 2017). Sweet cherry is grown almost everywhere in the temperate zone. It is a composite genus. Due to its origin, this genus needs warm and light conditions, but can also endure cold winter weather. It requires 550-600 mm precipitation annually. Sweet cherry prefers medium light (pH= 5.5–7.5), deep-layered soil, which is rich in nutrients. The root system of sweet cherry requires aeration and cannot tolerate slack water (Simon, 2004). Many areas of the world, although environmentally suited to cherry production, are currently unsuited to profitable cherry production due to high perishable nature of the fruit.

1. Introduction

The pistachio nut tree, Pistacia vera L. has been extensively cultivated since ancient times in the Middle Eastern and Mediterranean countries; in India, Afghanistan. The climatic conditions favorable to pistachio culture are similar to those for almond and olives, and prevail in extensive regions of the western United States also. Pistachio is a nut which comes originally from Iran and has the history of 4000 to 5000 years. Pistachio is a drought-tolerant, slow-growing, deciduous tree that reaches to a height of 30 ft. The tree survives in arid regions where summers are hot and the winters cold. Rocky, poor terrain with little rainfall is no problem as long as there is good drainage. The fruits grow in clusters. Although called a nut, botanically, pistachios are actually drupe. The pistachio consists of a bone ivory shell that encases the edible meat portion, called the seed.

Introduction 
Weather forecasting stands as a testament to humanity’s enduring quest to understand and anticipate the natural world. Far from being a mere casual prediction, it is a highly sophisticated scientific and technological discipline dedicated to projecting the future state of the Earth’s atmosphere for specific locations and times. This complex endeavor begins with the meticulous collection of vast quantities of real-time data, encompassing everything from surface observations of temperature, pressure, wind, and humidity to upperair measurements gathered by weather balloons, aircraft, radar, and advanced satellite systems. The core of modern weather forecasting lies in numerical weather prediction (NWP) models. These are intricate computer programs that embody the fundamental laws of physics governing atmospheric processes, such as fluid dynamics and thermodynamics. By feeding the enormous datasets of current atmospheric conditions into these models, supercomputers solve complex equations to simulate how the atmosphere will evolve over minutes, hours, and days. The raw output from these models is then further refined by human meteorologists who apply their expertise, integrating local geographical influences, historical patterns (climatology), and statistical techniques to produce the most accurate and actionable forecasts. The importance of accurate weather forecasting cannot be overstated. It serves as a vital tool across countless sectors, guiding daily personal decisions, from what to wear to whether to carry an umbrella. Crucially, for agriculture, precise weather forecasts are indispensable. Farmers rely heavily on these predictions to make informed decisions that directly impact crop yield and livestock health. Knowing when to plant seeds, schedule irrigation, apply fertilizers and pesticides, or harvest crops is directly influenced by anticipated rainfall, temperature extremes, and wind conditions. Timely warnings of frost, hailstorms, or prolonged droughts can enable farmers to take protective measures, minimizing losses and ensuring food security. For example, in regions like Telangana, where agriculture is a dominant sector, understanding

Key facts

Freshwater biotoxins

    
•    Biotoxins are naturally occurring toxic compounds produced by some freshwater cyanobacteria (blue-green algae) and marine algal species (dinoflagellates, diatoms).
    
•    Cyanobacteria are now recognised as a serious water quality problem with regard to drinking water supply and recreational use.
    
•    Environmental conditions that can promote cyanobacterial/blue-green algal blooms are: excessive nutrients (phosphorus and nitrogen); warm water temperatures (15-30OC); sunlight for photosynthesis; and quiescent or stagnant water.
    
•    Outbreak of human poisoning attributed to cyanobacteria are neurotoxins (e.g. anatoxin-a, anatoxin-a(s), saxitoxins) and hepatotoxins (e.g. microcystins, nodularin) produced by some strains of the cyanobacteria including Microcystis, Anabaena, Aphanizomenon spp.