eChapters

Crop evolution stands as a testament to the intricate dance between humans and nature, spanning millennia of coexistence and mutual influence. At the heart of agricultural history lies the story of how humble wild plants were transformed into the diverse array of crops that sustain humanity today. This narrative of adaptation, selection, and innovation not only shaped the course of human civilization but also continues to underpin the global food system in the modern era.
The Origins of Agriculture
The origins of agriculture mark a pivotal moment in human history, marking the transition from nomadic hunter-gatherer societies to settled agricultural communities. As early humans began to cultivate plants for food, they inadvertently initiated a process of selective breeding that would fundamentally alter the genetic makeup of these plants. Wild grasses such as wheat, barley, and rice were among the first to be domesticated, their seeds carefully harvested and replanted by ancient farmers who recognized their potential for sustenance.

Germplasm is the sum total of all the genes and their alleles present in a crop and its related species. Germplasm is also termed as genetic resources. It may be release as a variety, subjected to selection for developing a variety, and may be used as a parent in hybridization programme. They may be obtained from gene banks, center of diversity, gene sanctuary, farmer's field and seed companies.

Types of Germplasm

1. Land races

These are primitive varieties/cultivars. They are storehouse of genetic variability. Land races were first collected and studies by N.I.Vavilov in rice. They are the source of development of varieties in many valuable crops.

2. Obsolete varieties

The improved varieties of recent past are called as obsolete varieties. These varieties were breed by systematic breeding methods, were once commercially cultivated, but are no more grown. For example, wheat varieties K65, Ph591, many NP series etc.

Genetic resources deal with germplasm of a given species that provides the necessary genetic variation for the improvement of that species in terms of particular products, increased efficiency and higher levels of productivity. Genetic resources are, in this sense, the building blocks, fundamental not only to a crop improvement programme, but also for the very survival of the species in time and space (Swaminathan, 1983).

As agriculture is becoming more and more intensive and location-specific, plant breeding objectives are becoming more and more complex. Besides high yield, a modern variety is often expected to combine specific duration, nutritional attributes, adaptation to varying soil and water regimes, and resistance to ever-multiplying pests and diseases—to mention only a few of the character combinations. To meet these objectives, a wide range of germplasm must exist, and the plant breeder should have an easy access to the genetic resources.

ABSTRACT

Greenseeker is a handheld computer mounted sensor for observing normalized difference vegetation Index [NDVI= (NIR “R)/(NIR+R)], which may be used to estimate site specific amount of fertilizer nitrogen depending up on the crop condition. The sensor can be used for yield estimation and developing remote sensing based growth models. It is an active sensor with a built in light source for illuminating the target and records reflected light from vegetation at wavelength of 670 nm (red region) and 780 nm (near infrared region) of electromagnetic spectrum. The swath covered by the Sensor is 0.75 m when sensor is placed about 1.0 m above crop canopy.

The sensor was used to record NDVI in wheat- sugarcane intercropping system wherein wheat was grown on raised beds of 1.04 m width with six rows of wheat and sugarcane in furrows at row spacing of 1.38 m. The wheat variety PBW 343 was sown with nitrogen levels @ 0, 30, 60, 90, 120, 150, 180 and 210 kg N ha^-1 (all basal) and sugarcane variety CoSe 92423 was planted in furrows on 7^th November, 2006 in a medium textured loam soil.

The NDVI was recorded in wheat at 17, 41, 59, 73, 88, 113 and 129 DAS using Greenseeker and Spectroradiometer (UNISPEC ^TM of PP system, USA) simulating normal satellite bands i.e.

NIR: 770-860 nm, Red: 620-680 nm, Green: 520-580 nm. The maximum NDVI (recorded at 88 DAS) was used to develop INSEY “ yield relationship in wheat. The NDVI recorded by Greenseeker was integrated with NDVI recorded by Spectroradiometer.

The Greenseeker was also used to monitor crop growth in sugarcane. The NDVI was correlated with shoot population, plant height, LAI and total biomass during formative and crop elongation phase of sugarcane till end of November 2007. Highly significant (at 1%) correlation was observed between GS- NDVI and shoot population till mid August and LAI in sugarcane for entire crop cycle. An exponential model (R² = 0.9017) was developed to estimate LAI of sugarcane from NDVI. The NDVI was significantly (at 5 %) was correlated with plant height till mid August. However, the correlation between total crop biomass in sugarcane and NDVI remained non-significant.

Abstract

This paper portray the generation of spectral signature library for semi arid area crops using hyperspectral data and the scope of the application of the generated digital library for the classification of the satellite imagery of similar regions.

Hypersprctral data have narrow bands which help to provide additional information related to observed features. In case of this agriculture study crop related information are gathered using hyperspectral sensors The variation in the observations are due to physic-chemical characteristics such as biochemical composition, physical structure, water content and plant ecophysical status. Using the hand held spectroradiometer the reflectance is captured for the bajra, moong, moth crops from the Rajasthan, India’s semi arid region. The observations have been taken for different dates considering the phenology of the crops. Hyperion data from EO-1 satellite have been used to implement the classification operation based on the spectral signature library of bajra. It is observed that the image with the crops can be classified according to the phenology difference.

The term ideotype was proposed by Donald in 1968. Ideotype is a biological model which is expected to perform in a predicted manner in a defined environment. A crop ideotype is a plant model that is expected to perform better in a particular environment. The concept of ideotype changes from crop to crop, climate to climate and the concepts and policies of the community concerned. Ideotype breeding is the development of a plant type, expected more quantity of grains, with ideal character. Plant characters are selected from an agronomic point of view.

For crop improvement and more specifically to develop new varieties a number of plant breeding methods are available. CSIR-NBRI from very beginning selected all available techniques and standardized their practical application for all ornamental crops. All crop specific basic information was collected/generated for successful application of techniques for development of new varieties by creating genetic variability. Ornamental plant species fall into two main categories. In the first group the plants that are capable of sexual reproduction, but are commercially propagated vegetatively. The second group of plant species are the apomicts. In obligate apomicts hybridization fails to generate any variability. For development of new variety creation of genetic variability is pre-requisite. Breeder should have all up-to-date knowledge about all the available techniques and their merits and demerits for improvement and development of new varieties.

3.1. INTRODUCTION TO PLANT BREEDING

What is Plant Breeding?: Plant breeding is an art and science which deals with changing genotypes of the plants, to adapt them to the service of human being. (or) The application of genetic and cytogenetics principles in crop improvement are called plant breeding.

Specific objectives of plant breeding: The main objectives of the plant breeding is to improve the characteristics of crop plants which are agronomically and economically desirable

7.1. Crop insurance

Helps in stabilization of farm production and income of farming community.

Helps in optimal allocation of resources in production process.

Crop insurance is sold and bought in a market.

Has a limited role in risk management in farming.

Any limitations to scope for effective and economic crop insurance can change over time.

7.1 Introduction

Agriculture production and farm incomes in India are frequently affected by natural disasters such as droughts, floods, cyclones, storms, landslides and earthquakes. Susceptibility of agriculture to these disasters is compounded by the outbreak of epidemics and man-made disasters such as fire, sale of spurious seeds, fertilizers and pesticides, price crashes etc. All these events severely affect farmers through loss in production and farm income, and they are beyond the control of the farmers. With the growing commercialization of agriculture, the magnitude of loss due to unfavorable eventualities is increasing. The question is how to protect farmers by minimizing such losses. For a section of farming community, the minimum support prices for certain crops provide a measure of income stability. But most of the crops and in most of the states MSP is not implemented. In recent times, mechanisms like contract farming and future s trading have been established which are expected to provide some insurance against price fluctuations directly or indirectly. But, agricultural insurance is considered an important mechanism to effectively address the risk to output and income resulting from various natural and manmade events. Agricultural Insurance is a means of protecting the agriculturist against financial losses due to uncertainties that may arise agricultural losses arising from named or all unforeseen perils beyond their control (AIC, 2008). Unfortunately, agricultural insurance in the country has not made much headway even though the need to protect Indian farmers from agriculture variability has been a continuing concern of agriculture policy. According to the National Agriculture Policy 2000, "Despite technological and economic advancements, the condition of farmers continues to be unstable due to natural calamities and price fluctuations". In some extreme cases, these unfavorable events become one of the factors leading to farmers suicides which are now assuming serious proportions.Agricultural insurance is one method by which farmers can stabilize farm income and investment and guard against disastrous effect of losses due to natural hazards or low market prices. Crop insurance not only stabilizes the farm income but also helps the farmers to initiate production activity after a bad agricultural year. It cushions the shock of crop losses by providing farmers with a minimum amount of protection. It spreads the crop losses over space and time and helps farmers make more investments in agriculture. It forms an important component of safety-net programmes as is being experienced in many developed countries like USA and Canada as well as in the European Union. However, one need to keep in mind that crop insurance should be part of overall risk management strategy. Insurance comes towards the end of risk management process. Insurance is redistribution of cost of losses of few among many, and cannot prevent economic loss. There are two major categories of agricultural insurance

Abstract
Crop management and improvement are central to advancing agricultural productivity and sustainability. This comprehensive chapter delves into the strategies and techniques used in modern crop management and the ongoing innovations driving crop improvement. Covering topics such as crop rotation, soil management, pest and disease control, and the application of biotechnology, the chapter provides a detailed analysis of how these practices contribute to higher yields, enhanced quality, and environmental sustainability. The discussion also explores the role of precision agriculture, breeding technologies, and genetic modification in addressing the challenges posed by climate change, resource limitations, and changing market demands. By examining the latest advancements and best practices, this chapter offers
valuable insights into the future of crop management and improvement.
Keywords: Crop management, crop improvement, crop rotation, soil management, pest control, disease management, biotechnology, precision agriculture, genetic modification, sustainable agriculture.

With the current food production level of 275.11 million tonnes, India has to step up food grain production by next decade to feed the burgeoning population (Report Ministry of Agriculture). India with 2.3% of the global geographical area, supports about 16.8% human population, 20% of the world’s livestock. However, per capita availability of land for producing agricultural commodities has declined from 0.34 ha in 1951 to about 0.23 ha in 1980 and 0.15 ha in 0.15 ha during 2015 and it is expected to decline further to about 0.09 ha by 2050 A.D. With the possibility of horizontal expansion or putting more land under cultivation being remote, further augmentation in yield in Indian agriculture will be forced more and more into marginal or problematic soils accompany about 57% geographical area with increasing competition for good quality lands.

Problem soils are an important ecological entity of arid, semiarid or humid climate of our country. In India saline and sodic soils are serious threat to produce enough food grains for growing population. The other main problem is acid and acid sulphate soil, spread in one third of cultivated land.

Problem soils are either deficient in plant nutrients or the nutrient availability is inhibited by the antagonistic effect of the nutrient element present in excessive amounts as soluble or exchangeable ions.

The problematic areas for crop production may be soils affected with acidity, high concentration of salts, water logged soils or soils in steep sloppy areas. These soils have limitations or ill effects for crop growth and productivity.

The subject on micrometeorology deals with small scale meteorology of near ground surface with its related elements of both physical and biological processes. When this micrometeorology is integrated for crop production purposes, then it becomes crop micrometeorology, which is very important in the science of agricultural climatology. This crop micrometeorology gets varied with the architecture of the crops grown, available soil moisture, agronomical practices followed, soil texture, topography of the area, the nature of climate and weather that prevails etc. The soil surface heat, exerts a profound frictional effect on wind movements and hence it is different from the air layers at higher levels. These special features constitute the microclimate, which is modified compared to a flat bare surface by factors like topography, nature of soil surface, presence of vegetation and type of vegetative cover. The presence of crop canopy leads to distinct differences in the thermal and humidity regimes of the soil, the air layers immediately above it and the distribution of radiation and wind profiles inside the canopy. The study on the physical exchanges of the transfer of heat, momentum and moisture in the microclimatic region is called as micrometeorology (Venkataraman and Krishnan, 1992).

Radha Krishna Murthy (2002) reported that the micrometeorology is the micro scale of both the physical and meteorological factors that are taking place within the ecosphere. The ecosphere means the area between just above the crop canopy and just below the root zone of a crop. Further he was on the opinion that the microclimate of valley is important as compared to the entire climate of the mountain for the bio-life of valley. For the crops purpose, the microclimate is the climate of the ground surface to top of the crop canopy or otherwise it can be called as crop’s climate, a modified one from the Stevenson’s Screen climate/weather observation.

Introduction

Crop modeling in agriculture involves utilising quantitative data on eco physiological processes to forecast plant growth and development, leveraging environmental conditions and management inputs. These models simulate how crops respond whether in terms of growth, yield, or other factors to a dynamic interplay of elements like management practices, water, weather, and soil parameters throughout a growing season. They serve as computational tools emulating the intricate growth patterns of crops by mathematically representing various facets within the cropping system (Nath et al., 2023). The roots of crop modeling trace back to the 1960s, when researchers began integrating physical and biological principles to model agricultural systems. These models heavily rely on measurable inputs, obtained via sensors, machinery, or manual measurements, to predict desired outputs such as plant growth, crop yield, soil nitrogen levels, or crop staging.

Crop Modeling

Crop modeling involves the creation of mathematical or computational models that represent the growth, development, and yield of crops. These models are based on scientific principles and empirical data, aiming to simulate and predict various aspects of crop behaviour under specific conditions. The primary purpose of crop modeling is to provide a theoretical framework for understanding and predicting crop responses to environmental factors, management practices, and genetic variations.

5.1 Crop modelling

• Crop model

• “Schematic representation of the system’’i.e. a model as defined by De Wit 1970.

• Such a model can be based on statistics applied to a set of experimental data or on physical laws (Guyot, 1997).e.g. Irrigation is able to satisfy a crop’s water needs provided its management relies on the measurement or estimation of evapotranspiration. The manager can either invest in equipment to monitor changes in water content in the soil or fluxes of water into the plant or the atmosphere, or rely on a ‘‘schematic representation of the system’’, i.e. a model.

• In very simple terms we can define a crop model as “a well-thought out plan of activities to grow the desired crop to get maximum possible yields of high-quality produce with the given resources. It can be a mental or a written exercise (a “schematic representation of the system”) that a farmer or a farm manager prepares for a crop or for an individual crop”.

• In other words, we can also say that a model is “an attempt to describe a certain process or system through the use of a simplified representation, preferably a quantitative mathematical expression, that focuses on a relatively a few key variables that control the process or system”.

• It is clear that in finalizing a crop model we have to assume some mean or standard values (based on the past record, experience, expert judgment, etc.) of the variables which we may not be taking explicitly in our model.

Introduction 
The preceding chapter introduced the foundational concept of the systems approach, emphasizing the interconnectedness of components within complex entities and the power of simulation to understand their dynamic behavior. Building upon this understanding, This chapter delves into one of the most vital applications of system simulation in agriculture: crop models. These sophisticated computational tools stand as the cornerstone for quantitatively representing the intricate interplay between the soil, the plant, and the atmosphere, providing a dynamic lens through which to examine agricultural productivity and resource use efficiency. Crop models are essentially mathematical descriptions that mimic the growth, development, and yield of agricultural crops under various environmental conditions and management practices. They encapsulate our scientific understanding of how plants absorb light, water, and nutrients, how they convert these resources into biomass, and how they respond to stresses like drought, heat, or nutrient deficiency. Far from being mere statistical regressions, these are often process-based models, meaning they attempt to simulate the underlying biological, physical, and chemical mechanisms that govern crop performance. By integrating knowledge from disciplines such as plant physiology, soil science, meteorology, and agronomy, crop models provide a holistic and dynamic representation of the entire agricultural system. The evolution of crop modeling has mirrored advancements in computational power and scientific understanding. From early empirical models that relied heavily on statistical relationships between yield and a few environmental factors, the field has progressed to complex mechanistic models that simulate detailed physiological processes on a daily or even hourly basis. This evolution has transformed crop models from purely research-oriented tools into powerful instruments for real-world decision-making. Their ability to conduct virtual experiments—simulating hundreds or thousands of growing seasons

Crop nutrition / plant nutrition refers to the inter relationships of mineral elements in the soil and their role in plant growth and development. This inter relationship involves a complex balance of mineral elements essential and beneficial for optimum plant growth.

Plants require certain element for their growth and development. There are about 60 chemical elements present in the plant and it doesn’t mean that all are essential for normal growth and development.

Arnon and Stout (1939) proposed criterion of essentiality. Which were refined by Arnon (1954) and are popularly known as Arnon’s criteria of essentiality. They are:

Criterion for essentiality of plant nutrients

Arnon’s (1954) criteria for essentiality of elements for plant growth:

1. The plant must be unable to grow normally or complete its life cycle in the absence of the element,

2. The element is specific and cannot be replaced by another and,

3. The element plays a direct role in metabolism.

3.1. Growth Analysis

Growth and development analysis of plants provides information related to influence of various factors either negative or positive on plant growth. The basic idea of this analysis is the estimation of crop growth at various stages and finally towards the yield. It will help us to understand the performance of a genotype as well as impact of agronomic practices on the crop at any stage of growth and also on final yield. This would also identify the factors responsible for high yield and thereby provide the basis to tailor agronomic practices. The most common parameters used in growth analysis are leaf area index, crop growth rate, relative growth rate, net assimilation rate and leaf area duration.

1. The rice plant belongs to

   a) Short day plant

   b) Long day plant.

   c) Day neutral plant

   d) Etiolated

2. Cycoceal is a growth

   a) Growth inhibitor

   b) Growth hormone

   c) Growth regulator

   d) Growth stimulant

6.1. PLANT WATER AND MINERAL NUTRITION

Plant water

Water form the major constituent of living (cells) things and the cells originated in a highly aqueous medium and all the vital processes of the life are carried out in it. Besides, water predominately acts as a source of hydrogen to plants and is released by the photolys is of water during photosynthesis.

In living tissue, water is the medium for many biochemical reactions and extraction process. Inorganic nutrients, photosynthesis, bases and hormones are all transported in aqueous solution. Soil nutrients are available to plant roots only when it get dissolved in water. It is essential for life and plays a unique role in virtually all biological process.

Water absorption

Plants absorbed water through root hairs which are in contact with soil water and form a root hair zone a little behind the root tips.Root hairs are tubular hair like prolongations of the cells of the epidermal layer of the roots. When roots elongate, the older root hairs die and new root hairs are developed so that they are in contact with fresh supplies of water in the soil.

Mechanism of water absorption

1. Active absorption of water : In this process the root cells play active role in the absorption of water and metabolic energy released through respiration is consumed active absorption may be of two kinds.

Introduction

Research accomplishments on mentioned findings showed that the quality of community voice like access is familiarized for agricultural revamp index that adapted the charge to findings at the lower like as the antecedence to analyze a number of deficiencies of complete analysis works in a specific area. Firstly, the accomplishments arise to be alloyed and diverse. Secondly, with the agricultural achievement of a span afflict decidedly by its natural, institutional and technological characteristics (which alter broadly an allocation of states), absolute analysis absorption abundantly at the accompaniment like and the change of basal up and micro-level planning emphasizing the issue. Thirdly, there is an absence of studies on agricultural achievement at the disaggregate like in the accompaniment excepting a few that does put up with are bedfast to the community set up and are based on an actual leap amount of variables accouterment periods up to the original since the year 2000. Besides a lot of changes in agriculture pattern, irrigation coverage, agriculture intensity, fertilizer consumption, boilerplate measurement of operational backing and allotment of agricultural workers accept taken abode in agriculture during the contemporary years. These changes knowledge accept afflict the agricultural achievement of districts abnormally and causeless to say they could not accept been grasped in the absolute studies. There is appropriately a charge for advantageous these analysis gaps and adorning the absolute literature. The present findings are an apprehensive advance in the management and administration to apperceive of the ITKs attainable and its role in alteration over agricultural production. In adjustment to access the acknowledgment of the farmers apropos the ITKs uses in agriculture, the analysis agenda developed with a proforma that accomplished in advised and basic villages in altered agro-ecological regions through the activity centers. Farmers’ social contact and acceptance of ITKs practices were attempted in the findings and recorded for an all-important symbol the abstracts to quantify the ITKs role in present-day agriculture.

Introduction 
The preceding chapter elucidated the concepts of potential and achievable crop production, highlighting the significant gap that often exists between a crop‘s theoretical maximum yield and what is realized in the field. While genetic potential and optimal climatic conditions define the upper limits, the vast majority of agricultural systems globally operate under less-than-ideal circumstances. Among the most pervasive and impactful constraints on crop productivity are moisture (water) and nutrient limitations. These two factors, either individually or in complex interaction, are frequently the primary drivers of the yield gap, preventing crops from expressing their full genetic potential and significantly impacting farm profitability and regional food security. Water, as the universal solvent and a direct participant in photosynthesis and countless metabolic processes, is indispensable for plant life. However, its availability in agricultural systems is highly variable and often insufficient. From the rainfed fields dependent on increasingly erratic rainfall patterns to irrigated lands facing dwindling water resources, moisture stress – encompassing both drought and, paradoxically, waterlogging – poses an immense challenge. Drought alone accounts for a substantial portion of global crop losses, directly affecting plant physiological functions, growth, and ultimately, yield. Conversely, excessive moisture can lead to anaerobic soil conditions, nutrient leaching, and root damage, equally debilitating for crop performance. Parallel to moisture, the availability and judicious management of essential plant nutrients are foundational to productive agriculture. Plants require a suite of macro- and micronutrients for healthy growth, enzymatic activity, and the synthesis of biomass. Soils, over time and with continuous cropping, often become depleted of these vital elements, necessitating external application through fertilizers or the enhancement of natural nutrient cycling processes. However, nutrient management in the field is rarely perfect. Deficiencies of

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

4.1. PESTS OF FIELD CROPS

Insect pests are the major constraints limiting agricultural productivity growth. It is estimated that herbivorous insects eat about 26 percent of the potential food production. Emerging problems of insecticide and disease resistance, secondary pest outbreak and resurgence further add to the cost of plant protection. Annual crop losses due to insect pests and diseases in India are estimated to be 18 percent of the agricultural output. Main causes of emerging pest and disease are favourable prevailing weather condition, absence of natural enemies, abundant food supply, use of pesticides, use of fertilizers and irrigation.

PESTS OF RICE

Borers and Defoliators

Introduction

India is bestowed with diverse agro-climatic conditions which favour the production of a variety of fruit crops. At present India is second largest producer of fruits in the world after China. Fruit culture can be highly profitable by increasing employment opportunities and commercialization of the rural sector. During early sixties, priority was to achieving self sufficiency in food grain production in our country, however, over the years, fruit culture has emerged as an indispensable part of agriculture, offering a wide range of choices to the farmers for crop diversification. It also provides ample opportunities for sustaining large number of agro-industries to generate substantial employment opportunities (Bardhan, 2016). Amongst various tropical and sub-tropical fruit crops grown in India, guava, pomegranate, acid lime, sweet orange and mandarins, if left on its own, give several light crops of the variable quantities and qualities from the various flowering flushes throughout the year. Under natural conditions, these crops produce flowers thrice in a year i.e. February-March (Ambe Bahar), June-July (Mrig Bahar) and October-November (Hasth Bahar) with the corresponding harvest during rainy, winter and spring season, respectively (Boora et al., 2016, Lal et al., 2017). Owing to this, potential yield is not obtained during the desired period. Therefore, to obtain higher fruit yield during a particular period, these fruit crops are given a resting period with artificial means so that the natural flowering tendency of the trees is altered. It can be achieved through root exposure and its pruning (Boora et al., 2016), shoot pruning (Tiwari et al., 1992, Thakre et al., 2016)

Crop regulation in guava, flowering is more in summer season (Ambe bahar) due to the break of winter stress that leads to more fruit production in rainy season. But, in this season due to high temperature and rainfall during fruit maturation, the duration of maturation is reduced to 30 days that causes glut in the market, whereas winter season crop (Mrigbahar) is superior in quality which fetches comparatively higher price. Although, the production is surplus in rainy season (Rathore and Singh, 1974 and Singh et al., 2000), it offers poor quality due to insipid in taste and infestation of pest (Rawal and Ullasa, 1988) in comparison to winter season. On the contrary, in winter season quality fruits are produced with good quality and fetch high monetary returns (Singh et al., 2000). Guava fruit harvest peaks can deviate with prevailing weather conditions and cultural practices because flowers are produced on new growth. So, it is advisable to take only winter season crop every year. This requires crop regulation to obtain the most desirable crop, by the methods like withholding irrigation, thinning of flowers by chemically or manually, pruning, bending, root exposure, etc. The basic principle of crop regulation is to manipulates the natural flowering and fruiting of guava plant in desired season of the year that contribute to increased fruit yield, quality, profitability and sustainability of the environment by reducing the use of the frequency of the pesticides (Mahadevan and Kumar, 2014). The selection of bahar at a 

Crop Regulation

Staggering in pomegranate is practiced with a view to regulate crop load on the plant which will help in availability of the fruit for the long period helping the farmer fetching remunerative prices in the market. Also it will help in avoiding the glut in the market leading to distress sale. The relationship between source and sink can be regulated which helps in better fruit development. Pomegranate flowers and fruits through out the year if irrigation is provided to the plant. Taking of particular bahar leads to the glut in the market. This results in distress sale by the farmers. To avoid this staggering of pomegranate crop was attempted to find out and fruiting flowering during various months of the year so that maximum production with best quality fruits can be obtained.

Introduction
  
Horticultural production can be highly profitable, increase employment opportunities, and bring about increasing commercialization of the rural sector. Horticulture thus has a role to play in a world where 1.1 billion people continue to live in extreme poverty on less than US$1 a day and another 1.6 billion who live between one and two dollars per day (Von Braun et al., 2004). While in past, priority to achieving self sufficiency in food grain production in our country, over the years, horticulture has emerged as an indispensable part of agriculture, offering a wide range of choices to the farmers for crop diversification. It also provides ample opportunities for sustaining large number of agro-industries which generate substantial employment opportunities. The horticulture sector contributes around 28% of the GDP from about 13.08% of the area and 37 % of the total exports of agricultural commodities (Annon, 2007).

Large quantities of crop residues are produced and if properly used, they can provide cost effective means for supplying organic matter, plant nutrients and improved soil health. The highly lignocellulosic nature of crop residues indicate their potential role in maintaining soil organic matter and enriching the soils with N-rich microbial biomass resulting from decompositions. However, their indiscriminate handling often burning leads to decline in soil health, air pollution and overall loss. Since most crop residues find use as feed and fuel, efficient recycling of the remaining amount can have very significant and positive effect.

Large quantities of crop residues are produced and if properly used, they can provide cost effective means for supplying organic matter, plant nutrients and improved soil health. The highly lignocellulosic nature of crop residues indicate their potential role in maintaining soil organic matter and enriching the soils with N-rich microbial biomass resulting from decompositions. However, their indiscriminate handling often burning leads to decline in soil health, air pollution and overall loss. Since most crop residues find use as feed and fuel, efficient recycling of the remaining amount can have very significant
and positive effect.
The data regarding five major crops are shown. Even after use of some of them as animal feed they offer a great opportunity of using them back in to the soils which are hungry for organic carbon and other matters. Practice of Crop Residue Burning
The problem of collection and transport of crop residue and the short timebetween harvesting of one crop and making the farm free for the second crop has led to the harmful practices of crop residue burning. If instead of burning it, the residues can be incorporated into soils, a host of heterotrophic microorganisms bring about minor discharge of carbon and other elements contained in plant residues. A large increases in beneficial soil microbial populations and organic carbon can be achieved

Rice-wheat (RW) is the major cropping system occupying about 10.5 mha in the IGP of India. It contributes more than 60% of the foodgrains to the central pool. With shrinking land resources and burgeoning population, the RW system will be under pressure to produce more grain output per unit area in the coming decades. Meeting this challenging task requires sustainable management of soil, water and plant nutrient resources. High yields of the irrigated RW system result in production of huge quantities of crop residues. Total production of crop residues in Punjab is about 47.2 mt which includes paddy straw, wheat straw, cotton sticks, sugarcane leaves, maize stalk, and other oilseeds and pulse residues (Beri and Gupta, 2003). Wheat and rice straw constitutes more than 70% ofthe crop residues produced in the country. Paddy straw alone constitutes more than 50%. Cotton and sunflower residues are generally used as fuel. Sugarcane trash (leaves) is generally burnt in-situ or used as fuel after collection from the field. Increasing constraints of labour and time have led to the adoption ofmechanized farming in the highly intensive RW cropping system. Approximately 91% ofthe total rice area is mechanically harvested, while 82% of the total wheat area is mechanically harvested. Traditionally, wheat and paddy straws have been removed from the fields for use as cattle feed and for several other purposes such as livestock bedding, thatching material , for houses, and fuel. While more than 80% ofwheat residue is collected by the farmers after combine harvesting and often fed to animals, paddy straw is considered poor feed for animals due to its high silica content.

Substantial loss ofplant nutrients (especially N and S) and organic carbon occurs during burning of crop residues, with important implications to soil health. About 40% of the N, 60-85% of the K, 30-35% of the P, and 40-50% of the S absorbed by rice remains in the vegetative parts at maturity. One tonne of paddy straw contains approximately 6-7 kg of N, 1.0-1.7 kg of P₂O₅ and 14-25 kg K₂O. Apart from huge loss of precious plant nutrients, burning of crop residues depletes soil health. Air pollution from stubble burning also impacts human and animal health both medically, and by traumatic road accidents due to restricted visibility. In view ofthe serious problems associated with the residue burning, new ways are being sought to efficiently utilize the huge amount of surplus residues produced in the country.

11.1 Biomass

Globally, all agricultural countries have promoted the use of biomass sources for many household applications and biomass energy generation. Biomass is defined as the bio residue available from the sum of crop production, agricultural waste, vegetation, forestry waste and organic waste. Biomass is a renewable source of energy and contains a complex mixture of carbon, nitrogen, hydrogen, and oxygen. Various biomass resources are available in different parts of countries and are classified based on their availability. The broad classification of biomass energy is in three formats; residue of agricultural crops, energy plantations, and municipal and industrial waste. Agriculture residues are organic materials produced as the byproduct from processing and harvesting of agriculture crops. 

Indian crop production system excels in front of several biophysical adversities commonly known as biotic and abiotic stress.  Water is the principal factor limiting crop yield and about 2/3 of total cultivated landing India comprise of Dry land agriculture primarily under rainfed conditions with no or limited water supply system.  The Indian production systems are dominated by cereals, primarily rice maize, sorghum, pearl millet other coerces and fine cereals leguminous (urd bean, mung bean, peanut) and oil yielding crops during kharif and  wheat barley chickpea, lentil and forage legumes in rabi  season.  The production systems are generally characterized by cereal/legume mixed-cropping dominated by maize, millet, sorghum and wheat. The major constraints in both regions to crop production are low soil fertility, insecure rainfall, low-productive genotypes, low adoption of improved soil and crop management practices, and lack of appropriate institutional support. choice of crop  is important but selection of right varieties is utmost  important because  varieties which have proven excellent in irrigated or high rainfall areas are generally not suited for limited irrigated conditions.

Introduction

Through the use of both art and science, crop breeding is the process of enhancing significant agricultural plants for the benefit of humanity. Crop breeders attempt to improve the productivity and nutritional value of our food, f iber, pasture, and industrial crops via their efforts. In order to meet the needs of a growing global population with rising dietary demands, crops are essential. Additionally, the activity of crop breeders contributes to the improvement of environmental protection.

Since the beginning of agriculture, farmers have been selecting plants for desirable characteristics such as bigger seeds, more flavourful fruits, and other desirable characteristics. This method is known as plant breeding. In today’s world, the breeding of plants is a collaborative effort between scientists and farmers.

Different techniques are used by plant breeders, depending on the manner of reproduction of crops. This process is known as self-fertilization, and it occurs when pollen from one plant fertilizes the reproductive cells or ovules of another plant. There is a phenomenon known as cross-pollination, in which pollen from one plant can only fertilize another plant. For example, runners from strawberry plants are an example of asexual propagation, in which the new plant is genetically identical to its parent plant. Apomixis, also known as self-cloning, is a process in which seeds are created asexually and their offspring are genetically identical to their parents. When it comes to developing appropriate breeding and selection strategies, the mode of reproduction of a crop is the decisive element. This is because the genetic makeup of the crop is determined by the mode of reproduction. Additionally, it is necessary to have knowledge of the way of reproduction in order to artificially manipulate it in order to produce enhanced varieties. The only breeding and selection strategies that are appropriate for a crop are those that do not disrupt the crop’s natural condition or guarantee that it will remain in that form. The imposition of self fertilization on cross-pollinating crops results in a significant decrease in the performance of such crops for several reasons, including those listed above.

Introduction

The crops, its significance along with its classification has got paramount importance in agricultural heritage. A crop is a plant or animal product that can be grown and harvested in an area with a target to earn profit or achieve subsistence. Crop may refer either to the harvested parts or to the harvest in a more refined state (husked, shelled, etc.). Most crops are cultivated in agriculture or aquaculture.

A crop is usually expanded to include macroscopic fungus (e.g. mushrooms), or alga (alga-culture) at the point of origination. Most crops are harvested as food for humans or livestock (fodder crops) or to get raw materials for agro-based industry. Some crops are gathered from the wild collection (including intensive gathering). The important non-food crops include horticulture, floriculture and industrial crops. Horticulture crops include plants used for other crops (e.g. fruit trees, grown single or in orchard). Floriculture crops include blanket plants, houseplants, flowering garden and pot plants, cut cultivated greens, and cut flowers. Industrial crops are produced for clothing (fiber crops), bio-fuel (energy crops, algae fuel), or medicine (medicinal plants).

Microbes (fungi, bacteria or viruses) are rarely referred to as crops. Animals raised for human or animal consumption are referred to as livestock and microbes as microbiological cultures. Microbes are not typically grown for food itself, but are rather used to alter food (e.g., for production of citric acid, fermenting yogurt, soya sauce and so on). The importance of a crop varies greatly by region. Crop production depends on the availability of arable land and is affected in particular by yields, macroeconomic uncertainty, as well as consumption patterns; it also has a great incidence on agricultural commodities’ prices. The importance of crop production is related to harvested areas, returns per hectare (yields) and quantities produced. Crop yields stands for harvested production per unit of harvested area for the particular crop i.e. products. In most of the cases yield data are not recorded, but are obtained by dividing the production data by the data on area harvested. The actual yield that is captured on farm depends on several factors such as the crop’s genetic potential, the amount of sunlight, water and nutrients absorbed by the crop, the presence of weeds and pests infestation. These indicators are presented for wheat, maize, rice and soybean. Crop production is measured in tons per hectare, in thousand hectares and thousand tons.

Agricultural systems are complex, and understanding this complexity requires systematic research under shrinking agricultural research resources. Field experimentation can only be used to investigate a very limited number of variables under a few site-specific conditions. The crop growth simulation models simulate crop growth, development and yield taking into account the effects of weather, genetics, soil water, carbon and nitrogen, planting, irrigation and fertilizer (e.g. Nitrogen, Phosphorus) management. Ofthe many factors that potentially affect the growth of plants, the two that are most responsive to management are water and nitrogen. It is therefore not surprising that most crop models include routines to handle responses to water and nitrogen. Less frequently do models attempt to describe limitations due to other soil constraints (Probert and Keating, 2000). In the context of integrated nutrient management, the performance of a crop model depends mainly on its ability to adequately describe the release of nutrients from diverse inputs and their uptake by the crop.

Origins and genesis of a crop simulation model

Crop simulation model approach was started near about 50 years ago, in early 1960s when early simple crop models were developed for estimation of transpiration and photosynthesis. The first step towards crop modeling was the development of simple models to estimate light interception and photosynthesis (Loomis and williams, 1963; De wit, 1965 and Duncan et al., 1967). There are many crop growth simulation models. Some are more generic in nature while others are built for specific purposes. Most of these models simulate crop growth and soil processes using daily time steps. All models are developed with some assumptions and hypotheses, and all have strengths, weaknesses and limitations for appropriate application. Well-known crop modelling groups across the world include IBSNAT/IFDC (International Benchmark Sites Network for Agro technology Transfer/International Fertilizer Development Centre) in USA, WAU/AB-DLO (Wageningen Agriculture University/Centre for Agro-biological Research) in the Netherlands, and APSRU (Agriculture Production Systems Research Unit) in Australia. The IBSNAT project was initiated in 1982, and over the past 20 years it has developed more than 15 models, including CERES (Crop Estimation through Resource and Environment Synthesis) Rice and CERES Wheat, which are available either as stand-alone models or within the DSSAT (Decision Support System for Agrotechnology Transfer) shell (Uehara and Tsuji, 1993).

5.1 Introduction

A Crop Simulation Model is a mathematical model which describes crop growth and development processes as a function of environment, soil conditions, and crop management. Simulation model is a schematic representation which works on set of underlying assumptions, equations and algorithms, closely replicating the behaviour of the agricultural systems. A crop growth simulation model predicts the harvestable yield. Apart from this final state of crop production, the model also provides a host of quantitative information about major processes involved in the various stages of crop development. The information covers each component of the crop such as leaves, stems, roots and harvestable products as they change over time, including the changes in soil moisture and nutrient status.

An increase in the population, demands an increase in agricultural production with available resources. Efficient management of available resources under varying weather conditions is important for increasing agricultural productivity. Besides that, the emphasis of agricultural production changes from quantity to quality and sustainability (Aggarwal et al., 2000). Solution of these new challenges lies in understanding the interaction of the numerous elements affecting the plant growth and generating a crop growth model. This extremely complicated information needs to be processed and interpreted on a spatial scale. Information technology which has unleashed new frontiers in data analysis and automation is the driving force behind this model generation. These powerful computer programmes simulate the crop growth or yield of crops under various management regimes and provide near real time information to help farmers to make strategic decision in the management of their crops.

The susceptibility and vulnerability of crops to diseases are critical factors that determine the impact of disease outbreaks on agricultural productivity and food security. Crop diseases can have devastating effects on crop yields, quality, and marketability, resulting in significant economic losses for farmers and the agricultural industry as a whole. The susceptibility of crops to diseases refers to the inherent characteristics of the crop that make it more or less prone to infection by a particular diseasecausing agent. This can include factors such as the crop’s genetic makeup, its physiological state, and its environmental conditions. For example, some crop varieties may have a natural resistance to certain diseases, while others may be more susceptible due to their genetic characteristics. Vulnerability, on the other hand, refers to the degree to which a crop is exposed to disease-causing agents and is unable to withstand or recover from disease outbreaks. This can include factors such as the crop’s location, climate, soil type, and farming practices. For example, crops grown in areas with high disease pressure, inadequate soil moisture, or poor farming practices may be more vulnerable to disease outbreaks. Understanding the susceptibility and vulnerability of crops to diseases is essential for developing effective disease management strategies. By identifying the factors that contribute to a crop’s susceptibility and vulnerability, farmers and agricultural experts can take proactive measures to prevent or mitigate disease outbreaks. This can include using disease-resistant crop varieties, implementing integrated pest management practices, and adopting sustainable agricultural practices that promote soil health and biodiversity. In this chapter, we will explore the concept of susceptibility and vulnerability of crops to diseases in more detail, including the factors that contribute to these phenomena and the strategies that can be used to manage and mitigate disease outbreaks. By understanding the complex interplay between crops, diseases, and environmental factors, we can develop more effective and sustainable approaches to disease management that promote agricultural productivity and food security.
4.1 Factors Determining Susceptibility
The susceptibility of crops to diseases is determined by a complex interplay of factors, including genetic, physiological, and environmental factors. Genetic factors play a crucial role in determining the susceptibility of crops to diseases. Some crop varieties may have a natural resistance to certain diseases, while others

Introduction

The literary meaning of voyage is a long journey by water or air to a distance place. The crop voyage means the introduction of different crops from outside and movement of the crops originated in India to abroad. India is one of the mega agro-biodiversity countries of the world. Many plant species have been domesticated here. The agro-biodiversity of the indigenously domesticated higher plant species was further enriched with introduction of exotic crops since ancient times, as reflected by the presence of American cereals such as maize and amaranths, African cereals such as pear millet and sorghum, West Asian legumes such as field pea, grass pea and chickpea, and Chinese proso millet and buckwheat in the archeological remains and/or in ancient Indian agriculture writings. Most of these crops have acclimatized and adapted to diverse ecological conditions offered by the Indian Sub-continent to such an extent that many appear natural to the land, and have thrown enormous genetic diversity, making India either a secondary center of diversity for crops such as pearl millet, sorghum, maize, amaranths, cowpea, niger, safflower, muskmelon, pumpkin, chilies and others or regional center of diversity for crops such as barley, grain amaranth, buckwheat, pearl millet, foxtail millet, chickpea, bottle gourd and others. All details of crop voyage has already been discussed in the relevant topic of discussion (Chapter 8) on “Journey of agriculture and its development from past to modern era.”

Crop water requirement is the water required by the plants for its survival, growth, development and to produce economic parts. This requirement is applied either naturally by precipitation or artificially by irrigation. Hence the crop water requirement includes all losses like:

• Transpiration loss through leaves (T)

• Evaporation loss through soil surface in cropped area (E)

• Amount of weather used by plants (WP) for its metabolic activities which is estimated as less than 1% of the total water absorption. These three components cannot be separated so easily. Hence the ET loss is taken as crop water use or crop water consumptive use.

• Other application losses are conveyance loss, percolation loss, runoff loss, etc., (WL).

• The water required for special purposes (WSP) like puddling operation, ploughing operation, land preparation, leaching, requirement, for the purpose of weeding, for dissolving fertilizer and chemical, etc.

• Hence the water requirement is symbolically represented as:

The Crop Weather Calendar (CWC) is arguably one of the most practical and indispensable tools developed within agricultural meteorology. It transcends simple weather data by synthesizing comprehensive information about a specific crop’s entire life cycle with the historical climate patterns and recommended agricultural practices for a particular geographical area, typically an agro-climatic zone or even a district. More than just a timetable, it serves as a strategic blueprint that guides farmers and agricultural professionals toward optimized, resilient, and sustainable farming (Fig. 4.1).Imagine it as a detailed annual planner for a specific crop, where every entry is backed by decades of climate data and agronomic research. 4.2 Crop Weather Calendar: A Deeper Dive

Introduction 
Building upon our foundational understanding of how weather intrinsically shapes crop development, from the micro-scale physiological responses to the broader patterns revealed by Indigenous Technical Knowledge, we now transition to a chapter dedicated to a highly practical and actionable synthesis of this critical interrelationship: Crop Weather Calendars. These calendars are far more than mere chronological charts; they represent systematically organized and dynamic compilations of meteorological information meticulously integrated with precise crop-specific data, designed to serve as an indispensable guide for optimizing agricultural practices. In this chapter, we will embark on a comprehensive exploration of Crop Weather Calendars, moving beyond the often informal or culturally embedded ecological calendars previously discussed. We will delve into how these powerful tools systematically integrate historical weather patterns, which involves analyzing longterm meteorological data to establish reliable averages and identify probabilities of specific weather events, such as the typical onset of monsoons, average frost dates, or periods of peak solar radiation. They also incorporate real-time meteorological data, bringing in current weather observations to track actual conditions against historical norms and initial forecasts. Furthermore, Crop Weather Calendars utilize future weather forecasts, drawing on short-, medium-, and long-range meteorological predictions to anticipate upcoming conditions (Fig.12.1). This integrated weather information is then critically aligned with the precise phenological stages of a given crop cultivar, recognizing that a crop’s sensitivity and requirements vary significantly throughout its life cycle. Our exploration will detail the essential components that constitute a robust crop weather calendar, including the identification of crucial growth periods, pinpointing the most sensitive and influential developmental stages of the crop like germination, tillering, flowering, and grain filling, where weather impacts are most pronounced. It also involves the establishment of weather thresholds, which means defining the optimal, critical, and damaging ranges of key weather