eChapters

Introduction 
The mandate of the University under section 30 of the Act of 1963 is for establishment of Extension services for the purposes of under taking extension programs, dissemination of information for solving of problems relating to agriculture and domestic fields, developing the interests of youth in agriculture etc., The first extension service of APAU popularly known as District Extension Education Programmes were introduced in 1967 in Hyderabad district and were subsequently extended to Chittoor(1968)and Guntur (1970) districts. National Demonstrations Scheme (NDS) was established during 1970-71 in the University in four locations. In commemoration of the Golden Jubilee Year of ICAR, a Lab to Land Programme was launched by the APAU in June,1979. In order to improve the productivity of pulses and oilseeds in different regions of the state, two extension education centres were sanctioned by the ICAR at Ananthapur and Rastakuntubai which started functioning from December,1980 and December,1981 respectively. Reorganization of the University Extension work followed the reorganization of research activities of the APAU and implementation of Training and Visit System by the Department of Agriculture to streamline the setup of the field extension program of the University during 1982. To optimize the utilization of available extension resources, the resourcess of District Extension Education programs, extension services around research stations and NATP were integrated and reorganized to form six Extension Education Units. The extension activities of these units were entrusted with the respective Associate Directors of RARS for integrating research and action activities. The Associate directors of Research in turn were made responsible to the Director of Extension. The Extension Education Units conducted different extension activities like organization of field trials for testing new technologies for their feasibility including minikit trials of pre-released varieties to get feedback to the scientists, introduction of new cropping patterns, demonstration of latest technologies through early demonstrations including educational activities like organization of Kisan Melas training programs for the developmental

Introduction

A total of 109 elements have been discovered and incorporated into the periodic table. Many of these elements are found in the earth’s mantle, crust, and soil, though their abundance varies. The chemical makeup of plants is, to some degree, influenced by the composition of the soil. However, since plants are active organisms, they exhibit selectivity in absorbing elements from the soil. Plants accumulate elements at different rates, absorbing some in large quantities, others in smaller amounts, and excluding most altogether. Before proceeding, it is important to familiarise with several key terms frequently used in this chapter.

Nutrient: A nutrient element is essential for an organism to complete its life cycle, and a deficiency in this element leads to specific deficiency symptoms. The negative effects can only be corrected by providing that particular element. Nutrient elements essential for plants may not be necessary for other organisms, and vice versa. Depending on availability, the nutrient levels in a plant can be deficient, sufficient, or toxic. A nutrient is considered deficient when its concentration is so low that it significantly limits growth and causes recognisable deficiency symptoms. If nutrient levels cause reduced growth without visible deficiency symptoms, they are termed insufficient. The nutrient content range in plants that supports optimal yield of crops is considered sufficient. When the concentration of a nutrient becomes high enough to significantly reduce growth, it is considered toxic.

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

8.1. Classification of essential nutrients

8.1.1. Based on the amount required by the plant

Major nutrients-Required in large quantities eg. N, P, K.

Secondary nutrients-Required in lesser quantities compared to major nutrients eg. Ca, Mg, S.

Micronutrients-Required in trace quantities eg. Fe, Mn, Zn, Cu, B, Mo.

Terminology

    ·    Nutrient: Nutrients are substances required by an organism for their normal     growth and reproduction. 
    ·    Plant Nutrient: The plant nutrient is a “food” which is composed of certain chemical elements often referred to as ‘plant nutrient’ or plant food elements considered very essential for growth and development of plants. 
    ·    Nutrition: The supply and absorption of chemical compounds needed for growth and metabolism of an organism.

Agricultural meteorology, a discipline that has traditionally focused on understanding the relationships between weather and climate, and agricultural productivity, is at a critical juncture. The increasing vulnerability of agricultural systems to climate change, coupled with the need for sustainable and resilient agricultural practices, necessitates a fundamental transformation of agricultural meteorology. To support the development and implementation of climate resilient agriculture (CRA) practices, agricultural meteorology must be reoriented as a super speciality discipline. This requires a comprehensive overhaul of the discipline, including its curriculum, research focus, and practice. The reorientation of agricultural meteorology as a super speciality discipline is essential to provide the necessary expertise and knowledge to support CRA practices. This includes developing and applying cutting-edge technologies, such as precision agriculture, remote sensing, and machine learning, to support agricultural decision-making. However, the current state of agricultural meteorology is not equipped to meet the demands of CRA. The discipline faces several challenges, including a lack of interdisciplinary approaches, inadequate emphasis on practical skills, and limited focus on climate change and sustainability (Fig. 8.1). To address these challenges, essential reforms are necessary to reorient agricultural meteorology as a super speciality discipline. This chapter will discuss the essential reforms required to transform agricultural meteorology, including reforms in curriculum, research, practice, and policy. By implementing these

To set up a soil-testing laboratory the minimum requirements are as follows:

8.1 Laboratory floor area

Minimum four rooms are needed. They are as follows:

1. Office room, floor size: 18’x 12’

This room is used for registration of the soil samples received, recording recommendations along with soil test results in laboratory book and in report sheet, their dispatch, accounts etc.

[Bray’s Method (Bray and Kurtz, 1945) – Acid Soils]

Introduction

The term available phosphorus (P) refers to the inorganic form, occurring in the soil solution, which is almost exclusively ‘orthophosphate’. This orthophosphate occurs in several forms and combinations, and only a small fraction of the total amount present may be available to plants, which is of direct relevance in assessing the P fertility level.

The phosphate concentration in solution is governed by heterogeneous equilibria in which it takes part. This situation can be represented as follows:

P adsorbed in solid phase ↔ P in the soil solution ↔ P precipitated

The phosphorus absorbed by plants from soil solution comes from the soil solution in which it exists as inorganic orthophosphate ions viz., H₂PO₄ ^–, HPO₄ ^2– and PO₄ ^3–. The most accessible ion is H₂PO₄ ^–, with the greatest activity coefficient, followed by HPO₄ ^2–. The quantity of P accessible to the plants is influenced by a series of soil properties. The relative abundance of these ions is, however, relatively dependent on the soil pH. For soils having a pH between 4.5 and 7.5, ions of H₂PO₄ ^– as well as HPO₄ ^2– exist in soil solution. At a pH of 7.2, H₂PO₄ ^–and HPO₄ ^2– ions have an equal activity, and, when the pH is strongly alkaline (>8.3), ions of HPO₄ ^2– predominate in solution. Above pH of 9.0, the trivalent ion (PO₄ ^3–) becomes more important than H₂PO₄ ^–, but even at a pH of 12, the HPO₄ ^2– concentration is still greater than that of PO₄ ^3–. Soluble phosphorus may be adsorptively retained at the surface of colloidal particles. This retention is more marked when the higher amounts of clay and sesquioxides are present. Relatively, the available inorganic P tends to accumulate in its most stable state under prevailing conditions, thus, in calcareous soils, the available inorganic P would be acid-soluble, whereas, in acid soils the adsorbed P would be more available. In flooded soils, with low oxidation potential, certain forms of P, normally considered as unavailable, for example, iron and phosphate, can be regarded as available. In most soils, the main source of orthophosphate is organic matter unless, of course, direct fertilization, with soluble phosphate, has been made.

(Neutral Normal Ammonium Acetate Method)

Introduction

The total potassium (K) content of a soil varies from 0.05 to 2.5 %. The total K is distributed in mineral form (lattice – K, 90-98 %), fixed non-exchangeable or temporarily retrograded K (1-10 %) and exchangeable plus water soluble K (1-2 %). Exchangeable K represents an average of 2 – 15 % of the sum of exchangeable bases and 1 – 3 % of the total capacity for cation exchange. The K concentration in the soil solution is on an average 0.08 – 3 meq/litre. Both water soluble and exchangeable K are most accessible to the plant. Available K can, thus be separated into that, immediately available, which is water soluble and exchangeable, and that, potentially available or fixed. The neutral normal ammonium acetate extract contains both water soluble and exchangeable K. K extraction by this extractant is considered as a suitable index of K availability in most soils, based on crop response correlation study. Thus, the K extracted by this method is equated as the available K.

[Williams and Steinbergs (1959) Method]

Introduction

Sulphur (S) occurs in numerous forms in soil, viz., sulphites, sulphates, sulphides and in organic compounds. It is considered that the most accessible form is ‘sulphate’ (SO₄ ^2–). The organic forms of S compounds become assimilable, especially following, microbiological transformation into SO₄ ^2–. The mineralization of organic S in a soil depends primarily upon the N:S ratio, and any SO₄ ^2– formed may be fixed against extraction, particularly if much Fe or Ba is present or if the soil is very acid. Despite the fact that the plants absorb S almost exclusively as SO₄ ^2–, mobility of SO₄ ^2– in soil may not always yield satisfactory results in accordance with the time of sampling, while assessing SO₄ ^2– availability.

Objective

To determine the electrical conductivity (EC) of soil, which is an indicator of the soil’s salinity and its ability to conduct electricity. This provides valuable information about the nutrient availability and potential toxicity to plants.

Materials Required

• Soil sample

• Distilled water

• Electrical conductivity meter (EC meter)

• Beakers (100 mL)

• Measuring cylinder (50 mL)

• Stirring rod

• Filter paper and funnel

• Mortar and pestle (for soil grinding, if necessary)

The Electrical Conductivity (EC) of the soil is a measure of soluble salts present in the soil and is expressed as millimhos/cm or dSm^-1.

Principle

As the amount of the soluble salts in a solution increases, the electrical conductivity also increases. This electrical conductivity is measured in terms of resistance offered to the flow of current using a conductivity bridge.

It is known that solutions offer some resistance to the passage of current through them, depending upon the concentration of the soluble salts present. Hence, EC is measured in terms of electrical Resistance between parallel electrodes immersed in the soil water suspension.

In such a system, the solution between the electrodes becomes the electrical conductor to which the physical laws relating to resistance are applicable. The electrical resistance ‘R’ is directly proportional to the distance ‘L’ between the electrodes and inversely proportional to the cross sectional area ‘A’ of the conductor.

[Titrimetric/ Walkley and Black (1934) Method]

Introduction

The role of soil organic matter, in relation to soil fertility and physical conditions, are widely recognized. The organic matter is the source of plant nutrients which are released inassimilable forms during microbial degradation. A major proportion of N (95 – 99 % of the total), P (33 – 67 % of the total) and S (75 % of the total) in soils occur in organic combinations, which mineralize to release the nutrients in inorganic forms to be used by plants. Nevertheless, it serves as a reservoir of plant nutrients, in promoting water storage, and in regulating microbial activity.

The organic matter content of a soil varies from 0.344 % in very sandy arid soils to more than 86 % in Peats and Mucks. Soil organic matter contains 5 % N, and 0.5 % each of P and S, thereby, having a N:P:S ratio of 10:1:1. The organic matter content of a soil is estimated by the amount of organic carbon (C) present, as this element represents, on an average, 52 – 58 % of the organic matter, and the C:N ratio is 10 – 15. In the sub-soil, the average organic carbon amount is 36 – 44 % (40 %), and the C:N ratio is < 8. In order to find out the amount of humified organic material, the organic carbon content is multiplied by 1.724, which represents the ratio between the humus and the organic carbon (100/58) and is known as the ‘von Bemmlen factor ’.

The organic matter content of soils is estimated from the organic carbon, determined by using the ‘Titrimetric method / Walkley and Black method. The Titrimetric determination, also known as the ‘wet-digestion method’ involves a rapid titration procedure for the estimation of organic carbon content of soils.

Sample Digestion

Dry ashing and wet oxidation are two widely adopted methods for releasing mineral elements from plant tissues. Dry ashing, typically conducted at temperatures between 550 and 600 °C, can lead to the loss of phosphorus (P) and potassium (K) through volatilization. This method is more time consuming and has several drawbacks, such as the volatilization of sulfur (S) and chlorine (Cl), which can be mitigated by adding sodium carbonate (Na2 CO3 ). Additionally, some phosphorus and micronutrients may become occluded during the process, making dry ashing less commonly used.

In contrast, wet oxidation employs oxidizing acids, such as a mixture of nitric acid and perchloric acid (HNO3-HClO4 ) or a tri-acid mixture of nitric acid, sulfuric acid, and perchloric acid (HNO3-H2 SO4-HClO4 ). The use of perchloric acid (HClO4 ) prevents the volatilization loss of potassium (K) and provides a clear solution, while sulfuric acid (H2 SO4 ) aids in completing the oxidation. Upon heating, perchloric acid dissociates into nascent chlorine and oxygen, enhancing the oxidation efficiency at high temperatures. However, direct contact between perchloric acid and plant samples can lead to explosions and f ires; thus, pre-digestion of samples is preferred.

Sample Digestion

Dry ashing and wet oxidation are the two widely adopted methods for the release of mineral elements from plant tissues. Dry ashing is carried out usually at an ignition of 550 to 600 °C leads to loss of P and K by volatilization. Dry ashing being comparatively more time taking and also has a few drawbacks (such as S and Cl is lost by volatilization during ignition which can be prevented by adding Na2 CO3 ; a part of P and micronutrients also get occluded) is hence occasionally adopted. On the other hand, wet oxidation employs oxidizing acids like HNO3-HClO4 di-acid or HNO3-H2 SO4-HClO4 tri-acid mixture. The volatilization loss of K is prevented by the use of HClO4 and provides a clear solution while H2 SO4 helps completing oxidation. On heating HClO4 dissociates into nascent chlorine and oxygen, increasing the oxidation efficiency at high temperature. Explosion and fire may occur if there is direct contact of HClO4 with plant sample; hence the pre-digestion of samples is preferred. Digestion with HNO3-HClO4 instead of tri-acid mixture is also adopted specially when S is also to be determined in the same digest. The wet oxidation method being less time-consuming, easier and convenient is given below:

The Walkley-Black method is a widely used chemical procedure to estimate soil organic carbon (SOC). It involves the oxidation of organic carbon by potassium dichromate in the presence of sulfuric acid, followed by titration to determine the amount of unreacted dichromate. Here is a detailed step-by-step guide:

Materials Required

• Soil sample (air-dried and sieved through a 2 mm sieve)

• Potassium dichromate solution (1 N)

• Concentrated sulfuric acid (H2 SO4 )

• Ferrous ammonium sulfate solution (0.5 N)

• Orthophosphoric acid (H3 PO4 ) (optional)

• Diphenylamine indicator or N-phenylanthranilic acid (indicator)

• Distilled water

• Burette, pipette, and conical flasks

• Heating mantle or hot plate

The pH is defined as negative logarithm of hydrogen ion concentration or the log of the reciprocal of the hydrogen ion concentration (Sorenson, 1906).

Principle

A glass electrode in contact with hydrogen ions of the solution acquires an electric potential which depends on the concentration of hydrogen ions. This is measured potentiometrically against some reference electrode which is usually a calomel electrode. The potential difference between glass electrode and calomel electrode is expressed in pH units.

Two electrodes are used in the determination of pH. One is reference electrode which provides a standard voltage and is usually a saturated calomel electrode which has two layers of saturated solution of KCl and mixture of solid HgCl₂ and Hg. The outer tube is usually 5-15 cm long, 0.5-1 cm in diameter. The mixture of solid HgCl₂ + Hg paste is contained in an inner tube that is connected to the saturated KCl solution in the outer tube by means of small opening. The resistance developed by this type of electrode is 2000-3000 Ohms.

The outer electrode is glass electrode that consists of a tube enclosing a lead wire made up of Ag coated with AgCl. This wire is again enclosed in a wax insulation. To the tube at the bottom is attached a glass bulb made up of a special kind of glass which is sensitive to hydrogen ions. The thickness of the glass membrane varies from 0.03 to 0.1 mm and has a resistance of 50 to 500 mega Ohms.

When these electrodes are dipped in solution, the saturated solution of KCl comes out of reference through small holes and forms an invisible ionic bridge between electrodes through which current passes. The hydrogen ions are absorbed by glass electrode and depending upon the amount of hydrogen ions present in the solution, an electric potential develops between electrodes. This potential difference is measured in terms of pH units by suitable Galvanometer.

Objective
To produce ethanol from lignocellulosic biomass (e.g., paddy straw)
through a series of biochemical processes pretreatment, enzymatic saccharification, and microbial fermentation and to evaluate sugar yield, ethanol concentration, and fermentation efficiency.
Introduction and Theoretical Background
Ethanol (C2H5OH), commonly known as ethyl alcohol, is one of the most important biofuels and renewable energy sources in the modern era. It is a clear, volatile, and flammable liquid that can be used both as a fuel additive (blended with gasoline to form gasohol) and as an independent energy source in modified internal combustion engines. In addition, ethanol is extensively used in the pharmaceutical, beverage, and chemical industries. Globally, more than 30 billion litres of ethanol are produced annually, primarily via fermentation of sugar-rich feedstocks such as sugarcane juice, molasses, and starch-based crops like maize and wheat. However, reliance on these food-based resources has raised sustainability and food security concerns. Therefore, attention has increasingly shifted toward lignocellulosic biomass, such as agricultural residues (paddy straw, corn stover, bagasse, etc.), which are abundant, renewable, and inexpensive.
Paddy straw, a by-product of rice cultivation, is a promising raw material for bioethanol production due to its high cellulose (30–40%) and hemicellulose (20–30%) content. However, the complex structure of lignocellulosic biomass, reinforced by lignin and silica, restricts enzyme accessibility to polysaccharides. Hence, pretreatment is essential to break down lignin and enhance enzyme digestibility before fermentation.

Introduction
The use of animals in scientific research has been a cornerstone of medical advancements for decades. However, this practice has also been the subject of intense ethical debate. This lecture explores the necessity of animal experimentation, the ethical considerations involved, and the regulatory frameworks in place to ensure the humane treatment of laboratory animals.
The Need for Laboratory Animals
Animal experimentation has played a crucial role in numerous medical breakthroughs. The importance of laboratory animals in research cannot be overemphasized. Among the various purposes for which humans use animals, experimentation involves relatively few animals and serves a noble purpose in advancing scientific knowledge and human health.
Laboratory animals are invaluable in the drug development process for several reasons:
• Similarity to human organ systems, metabolism, and enzyme functions.
• Suitability as alternatives to human subjects.
• Small size and ability to be reared in controlled environments.
• High reproductive rates.
• Potential for genetic purity, leading to reproducible and reliable results.
The Importance of Animal Welfare
While the benefits of animal experimentation are clear, it’s equally important to consider the ethical implications of using animals for research. The concept of animal welfare is embedded in the Indian Constitution, which states that it is the duty of every citizen “to protect and improve the natural environment including forests, rivers, lakes and wildlife, and to have right compassion for the living creatures” (Article 51 A (g)). This ethical consideration for animals has been emphasized by philosophers, spiritual leaders, and scientists throughout history:

An ancient Chinese proverb says

If you are thinking one year ahead, plant rice
If you are thinking ten years ahead, plant trees
If you are thinking hundred years ahead, educate the people

Subramanya Bharati, a great Tamil poet, wrote decades ago that nutrition and education were the two legs of a human being — nutrition for the body and education for the mind. We must, therefore, foster a movement for integrating academic excellence and social relevance in the curricula of our educational institutions. Our universities should promote the growth of the science of ecotechnology, which is the product of the integration of traditional knowledge with frontier science. This will need a mind-set change in relation to the knowledge and wisdom of our tribal and rural families.

In the 1990s, I developed the Iwokrama Rain Forest Programme, which represents the world’s largest adventure in the sustainable management of rainforests. The local Amerindian population welcomed me to Iwokrama with a song, which translates thus:

The credibility of academic publishing hinges significantly on the integrity of journal rating systems. These systems, designed to evaluate and rank academic journals based on various metrics, play a pivotal role in shaping research priorities, funding allocations, and academic career trajectories. However, despite their importance, many journal rating systems are criticized for lacking transparency and ethical rigor (Fig. 10.1).
This chapter explores these shortcomings, focusing on potential biases embedded in current systems and proposing solutions to enhance their transparency and fairness.
10.1. Role of Journal Rating Systems in Academic Publishing
Journal rating systems serve as gatekeepers in the academic publishing ecosystem. They influence where researchers choose to publish their work, how institutions evaluate scholarly output, and how funding agencies allocate resources. Metrics such as impact factor, h-index, and SCImago Journal Rank (SJR) are commonly used to rank journals. These metrics, while useful, often reduce the multifaceted nature of scholarly impact into single numerical values, potentially oversimplifying and distorting the evaluation process. The reliance on these metrics creates a feedback loop wherein highly ranked journals attract more submissions, increasing their citation counts and reinforcing their dominance. This system can marginalize smaller or niche journals that publish

Introduction

The term 'research ethics' in social science research refers to human values, norms, and society approved arrangements that regulate scientific understanding go for society. It consists of the set of values, standards, and principles that serve as benchmark to determine appropriate and acceptable conduct tall stage soft he research process. It is the implementation of ethical practices that specifies norms and values as well as responsibility towards the academic community and society as a whole. 

Introduction

In India about 8.6 per cent of population enlisted in the category as ‘Scheduled Tribes’ under Article 342 of the Constitution of India, but they constitute almost 16 per cent of the poor. Lakshadweep is the most populous state with respect to proportion of tribal to total population (94.8 per cent) whereas, in Uttar Pradesh tribal population is lowest with only 0.6 per cent of the total. In Odisha tribal constitutes 22.8 per cent of total population. In India literacy rate of tribal is 59 per cent as against that of general category is 69 per cent. Tribal people are observed to be strongly associated with the forests, hills and remote areas, practising a unique life style, having a unique set of cultural and religious beliefs. Over the generations these communities have evolved time tested farming systems, which are purely subsistence in approach and are keeping pace in perfect harmony with nature. Over the recent few decades, however, population growth and lack of harmony between different agriculture and developmental policies have threatened these traditional agricultural systems for extinction. The encroachment of local Governments and private interests on forest and mineral resources has pushed the tribal groups on to increasingly degraded land, thus their survival became a constant struggle.

The primitive societies have passed through several stages of economic development everywhere in the world. Thus one can find the stages of food gathering, hunting and fishing, farming, etc. among the Indian tribes. The tribes living in the forests and hills usually earn their livelihood by means of food gathering, hunting and fishing. Such is the life of Kadar of Kerala, Birhor and Kharia of Bihar and other tribes. The tribes living in dense forests, full of wild beasts, live on hunting, such as the tribes of Naga, Kuki, Bhil, Santhal and Gond. The hunters leave the females to carry out household activities in the morning and return in the evening after hunting. In some tribes there is a usual custom of hunting collectively. The Nagas use spears, arrows and bows. The Bhils are very much specialized in shooting by arrow. The tribes living near rivers and seas usually earn their livelihood by catching fish. The hilly tribes rear the cattle, an example of which are Goojars and the tribes of Chamba. The Todas of Nilgiri rear buffaloes. Some tribes also carry out cultivation, but they are generally shifting from one place to another. So shifting cultivation is an intrinsic part of tribal system and tradition. Among the cultivating tribes are the Santhals and Gonds. Tribal groups mostly do not have land ownership and have a limited option to adopt agricultural operations in forest areas. Considering their sustenance Government of Odisha has passed an Act “Schedule Tribes and other forest dwellers Forest Right Act” in 2006. It permits ownership of tribals on forest land up to 4 ha. for forest use and subsistence agricultural activity without any penalty. Cottage industries, such as weaving cloths, preparing ropes and skins and utensils of different metals are prevalent in many tribes. The Kharia people are very much specialized to cottage industries. Their living standard is very poor in spite of their hard work.

Minor millets, that belong to members of the cereal grass family, are advantageous in areas where large crops like Bread wheat, Rice paddy, and maize are relatively ineffective because they have a wide range of genetic diversity and thrive in marginal environments. The varied soil types, temperatures, heat and light cycles, and rainfall patterns across India all support the cultivation of minor millets. Finger millet, barnyard millet, foxtail millet, proso millet, and many more types of minor millet are used in agriculture. The majority of those who depend on these millets for sustenance and income are small-scale indigenous farmers and dwellers of rainfed areas, mainly among impoverished tribal populations numbering in the millions. Coarse cereals,now a days known as Nutri cereals or nutraceutical flora and are no longer known as coarse cereals as a potential global answer to malnutrition and unrecognized hunger. Minor millets have long been an essential component of Indian tribal societies’ agricultural systems and practices. They have used little millets for both famine prevention and ethnomedicine since the beginning of time. This chapter focuses on how little millet could help people have access to food and nutrition security while reducing hunger and malnutrition.

13.1 Introduction

Eutrophication, means an increase in chemical nutrients — typically compounds containing nitrogen and phosphorus in an ecosystem. It may occur on land or in water. The term is however often used to mean the resultant increase in the ecosystem’s primary productivity (Fig. 13.1), in other words excessive plant growth and decay and even further impacts, including lack of oxygen and severe reductions in water quality and in fish and other animal populations.

Successful irrigation development requires careful evaluation of soil and land characteristics before irrigation is introduced or expanded. This chapter deals with the principles and criteria used to evaluate land for irrigation and determine its suitability for sustained agricultural production. Important soil and land characteristics considered include surface-soil texture, particle-size class of the subsoil, coarse fragments, soil depth, permeability, salinity, exchangeable sodium percentage, slope and drainage. These factors determine the ability of land to store and transmit water, support root growth and withstand potential problems associated with irrigation. The chapter introduces land irrigability classification and explains the overall capability index (Ci), including its calculation and interpretation. Subclasses are considered to identify specific limitations affecting irrigated agriculture. The chapter further discusses land suitability classification and the structure used for assessing suitability. Physical condition of soil is included as an important component of land evaluation. By integrating soil, water and landscape characteristics, the chapter provides a systematic basis for identifying suitable land, recognizing limitations and planning sustainable irrigation development.

Summary

The soil is the basis of agriculture as the productivity of the farm enterprise is strongly linked to the fertility status of the soil. The soil acts as a reservoir for the essential nutrients that crops need for growth. When these nutrients are in sufficient quantities and balance, agricultural productivity is greatly enhanced. On the other hand if the nutrients are in short supply and imbalanced, crop growth is hampered. When crops grow and produce harvest, they remove nutrients from the soil. These nutrients are exported when the grains or edible parts are eaten and the stover removed. Consequently with time, a soil that is considered fertility will also lose its fertility if no nutrients are added periodically. It is important to assess the fertility status of the soil before planting and all necessary ameliorations effected in time to ensure a good harvest. Various methods exist for evaluating soil fertility. The best indicator of a fertile soil is good growth of crops growing on it.

Abstract

The paper presents an approach of selecting suitable areas for artificial groundwater recharge structures through remote sensing and integrated terrain analysis by statistical method. The study area “Ayyar basin” is an aquifer system of gneisses and charnockite litho-units in Tiruchirappalli district, Tamil Nadu. The area has witnessed a steady decline in groundwater table. Hence, the scope for artificial groundwater recharge was studied in this area with the help of Tamil Nadu State Council for Science and Technology (TNSCS&T).

Introduction 
The preceding chapters have laid a robust foundation, introducing the concept of agricultural systems, delving into the architecture and types of crop models, and meticulously detailing the essential data requirements for their operation. We have established that crop models are powerful tools for simulating the complex interactions within the soil-plant-atmosphere continuum, driven by a rich tapestry of environmental and management inputs. Among these inputs, weather stands out as arguably the most dynamic and influential factor, wielding profound control over every aspect of crop life, from the precise timing of germination to the final quantity and quality of the harvest. Chapter 5 shifts our focus to the direct and indirect consequences of this critical environmental driver: the evaluation of crop responses to weather. This chapter is dedicated to understanding, quantifying, and interpreting how variations in meteorological conditions—such as temperature, solar radiation, precipitation, humidity, and wind—directly influence the physiological processes, developmental progression, biomass accumulation, and ultimate yield of cultivated crops. It‘s about moving from simply providing weather data to actually assessing its impact on the plant‘s performance. The ability to accurately evaluate these responses is paramount for several interconnected reasons: Firstly, from a fundamental scientific perspective, it deepens our understanding of plant ecophysiology. By analyzing how crops react to specific weather patterns, we gain invaluable insights into the underlying biological mechanisms that govern growth and development under diverse environmental pressures. This knowledge is crucial for advancing agricultural science itself. Secondly, for agricultural management and decision-making, this evaluation is directly actionable. Understanding optimal weather conditions for specific growth stages, or predicting the impact of adverse events, enables farmers

ABSTRACT

The present study reports shoreline changes at Gopalpur along east coast of India for 30 years during 1973-2003. In order to understand the trend of sediment transport, shoreline changes at the vicinity areas viz. Rushikulya and Bahuda estuaries are also discussed. Geomorphological investigation is also carried out to understand the processes acting on this system. One Landsat image (1973) and two IRS 1C/1D images (1993 and 2003) were used for the study. The data were subjected to digital analysis using ERDAS Imagine and management of information layers using ARC/INFO GIS software. The results of the study show that the changes occurred differently in three distinct spatial features namely, i) sand spit ii) beach and, (iii) channel zone. Changes documented in these imageries reveal that the lengths of NE spit and SW spit are increased and decreased respectively in thirty years. Areas of NE and SW spits are also showing the similar pattern. Beach is almost stabilised and a slight decrease of 0.28 km in length is observed. However, area has been increased in the southern beach. Towards north, the beach area is also increased over a period of thirty years. The change of width of the beach is not found to be significant. The mouth near channel zone is reduced to 70 meter from 135 meter during the period of study.

The change of state of water from solid and liquid to the vapour and its diffusion into the atmosphere is referred as Evaporation. In the meteorology, evaporation is defined as the maximum possible loss of moisture from a wet, horizontal, flat surface exposed to weather which exist in the vicinity of plants.

FACTORS AFFECTING EVAPORATION

1. Those affecting water supply at the evaporating surface. i.e., soil and plants including soil storage capacity, rainfall and irrigation and

2. Those affecting energy supply to the evaporating surface like solar radiation.

This chapter is fundamental to agricultural water management, as it explains how water moves from the land surface and plants back into the atmosphere, directly influencing irrigation needs and drought impacts. Water is the lifeblood of agriculture, and its efficient management is paramount for sustainable food production. Understanding how water is lost from the soil and plants to the atmosphere is central to optimizing irrigation and assessing crop water needs. This chapter delves into the concepts of evaporation, transpiration, their combined effect as evapotranspiration, and how these relate to overall crop water use (Fig.5.1).

Definition: Evaporation is the physical process by which liquid water is converted into water vapor and transferred from the land surface (e.g., bare soil, water bodies, or wet plant surfaces) into the atmosphere. It is purely a physical process driven by solar energy and the vapor pressure gradient between the surface and the air.

Evapotranspiration is the combination of two separate processes named evaporation and transpiration. Evaporation accounts for the movement of water to the air from sources such as the waterbodies and soil. Transpiration accounts for the movement of water within a plant and the subsequent loss of water as vapour through stomata in its leaves. So evapotranspiration is a bio-physical process.

Evaporation

The change of state of water from liquid to the vapour and its diffusion into the atmosphere is referred to as evaporation. During evaporation, water molecules absorb energy which gives them the motion required to escape from the surface of liquid and become a gas. Since a certain amount of energy is consumed in the process of evaporation, the remaining liquid is cooled by an equivalent amount. Thus, the process of evaporation is always accompanied by a cooling effect.

As evaporation proceeds, the surrounding air becomes gradually saturated with water vapour and the process will slow down and might stop if the wet air is not transferred to the atmosphere. The replacement of the saturated air with drier air depends greatly on wind speed. Hence, solar radiation, air temperature, air humidity and wind speed are meteorological parameters to be considered when assessing the evaporation process.

In agrometeorology, evaporation is defined as the maximum possible loss of moisture from a wet, horizontal, flat surface exposed to weather parameters, which exist in the vicinity of plants. Evaporation is an essential part of the water cycle. It is the primary pathway through which water moves from the liquid state back into the water cycle as atmospheric water vapour. The oceans, seas, lakes and rivers provide nearly 90 per cent of the moisture in the atmosphere via evaporation, with the remaining 10 per cent being contributed by plant transpiration. A very small amount of water vapour enters the atmosphere through sublimation, the process by which water changes from a solid (ice or snow) state to a gaseous one, bypassing the liquid phase.

The movement of water from soil to the crop canopy and leaves to provide water for transpiration and the effect of weather factors on transpiration is most important area of study. When the crop is just sown, there will be an only evaporation of water from the soil. After germination of seeds there will be emergence of seedlings. After the emergence of seedlings there will be formation of leaves. The small leaves start intercepting the incoming solar radiation and absorb some portion of solar energy, get heated and there will be evaporation turn off water from the stomata of the leaf. When water vapour escapes into the atmosphere through the stomata of leaf, the plant absorbs carbon dioxide which results in photosynthetic activity. During night time, there will not be any photosynthesis due to absence of sunlight. The plants use parts of the photosynthetic accumulate for its metabolic activity and the process is called maintenance respiration. The balance of the photosynthetic accumulate contributes to the expansion of leaves and increased dry matter accumulation in crop plans. The process of dry matter accumulation in plants is called crop growth. When the seedlings start growing, there will be formation of tillers or branches. When the leaves grow it reaches a stage when the crop will be completely shading the ground and the soil evaporation will be minimum and maximum amount of water is lost only through evapotranspiration (Fig.6.1).

In cropped soils, evaporation refers to evaporation of water from the soil and transpiration refers to evaporation of water from plant canopies (Fig.6.1). Evaporation and transpiration play very significant role in mass and energy transfer. The latent heat of vaporization is defined as amount of heat required to evaporate 1 gm of water at a temperature of 100°C; i.e. the boiling point of water is 540 cal/gm. The amount of heat required for evaporation of water at ordinary temperature of about say 30°C is 610 cal/gm.
Fig. 6.1: Process of evapotranspiration
The evapotranspiration from crop depends upon several factors as indicated below:
• The evapotranspiration increases with increase in air temperature.
• The evapotranspiration increases with increase in wind speed up to a certain limit.
• The evapotranspiration decreases with increase in relative humidity
• The evapotranspiration increases with increase in Saturation Vapor Pressure Deficit (SVPD). SVPD = es – ea

The geologists of the Indian subcontinent have all along been of the opinion, that, the southern part of the Indian Peninsula is a stable shield area. But, the recently acquired IRS-1A image of June, 1988 vividly displays spectacular geomorphic anomalies suggesting that this part of the Indian subcontinent is prone to earth movements. In order to unearth more evidences on such earth movements / neotectonism in Tamil Nadu, the IRS-1A image of Coromandel coast of Tamil Nadu was analysed ( Fig. 1).

OBSERVATIONS

• The IRS-1A image conspicuously displays three contrasting morphotectonic domains in the study area marked by the western undissected Tertiary upland (Vallam upland), central highly dissected Tertiary upland (Pattukottai -Mannargudi upland) and the eastern Cauvery delta (Fig 1 and 2). These three domains are separated by two conspicuous N-S trending lineaments (E and F, Fig.1 and 2) namely the Tanjavur - Avadaiyarkovil lineament in the west and Kumbakonam -Muttupet lineament in the east.
• In addition, two more E-W trending lineaments (G and H, Fig.1 and 2) are also observed trifurcating the undissected Vallam upland into three blocks.
• Along these lineaments, especially the Tanjavur -Avadaiyarkovil and Kumbakonam -Muttupet lineaments, the rivers show conspicuous drainage anomalies in the form of drainage deflection, drainage compression etc., wherever they transect the lineaments.

Introduction Agricultural extension plays a pivotal role in the advancement of agriculture in any nation. It encompasses the dissemination of knowledge, guidance, and assistance to farmers, rural communities, and various stakeholders involved in the agricultural domain. The primary objective of agricultural extension is to empower farmers to enhance their productivity, income, and overall quality of life. The concept of agricultural extension has undergone significant transformations across various countries, including India. This article will delve into the historical progression of agricultural extension both internationally and within the Indian context.

Abstract

Camelids across the world are reared for milk, meat, draught, race and tourism. Camelids are also the source of world’s finest natural fibre. They are distributed in the South American, African, Arabian and Asian countries. Apart from this a feral population exists in Australia and recent reports indicate that a few animals of the species are also being reared in Europe. Camel (Camelus dromedarius) is the predominant species of the camelids. The world camel population shows an increasing trend with 12.92 m in 1961 to 26.63 m in 2011 producing 0.42 m tonnes of meat and 2.11 m tonnes of milk per annum. The top 20 camel rearing countries produce both milk and meat with the exception of India and Pakistan as per FAO data. There are about 83 populations of the dromedary camels in the world spread mainly across African and Asian countries. There are about 3.04 m Alpacas in world with Huacaya and Suri as the two main populations and 3.24 m Llamas with Chaku and Kara as the two main populations. The Guanaco population in the world is about 0.5 m and that of Vicuna is 0.35 m. The wild Bactrian camels are around a thousand but the domesticated Bactrian camels are about 0.6 m. The Alpaca and Bactrian camel genome has been sequenced whereas the expressed sequence tags of the Dromedary are available in the public domain. A brief account of evolution, present status and conservation of camelids is discussed.

Exchanges sodium (Na+) is animportantparameter forsalt affected soils. This is estimated by extraction with ammonium acetate and then measuring the extract inflamephotometer.

Reagents

1. Neutral normal ammonium acetate solution (1 N CH₃COONH₄ of pH 7): Dissolve 77.09 g of ammonium acetate in distilled water and make up the volume to one litre. Adjust the pH of the solution to 7 with ammonia solution or acetic acid.
2. Standard solution of Na (500 mg/L Na): Dissolve 1.271 g of NaCl in distilled water and make up the volume to one litre.
3. Working standard solution of Na (100 mg/L): Dilute 200 ml of 500 mg/L stock solution to 1000 ml.

Organic farming system in India is not new and is being followed from ancient time. It is a method of farming system which primarily aimed at cultivating the land and raising crops in such a way, as to keep the soil alive and in good health by use of organic wastes (crop, animal and farm wastes, aquatic wastes) and other biological materials along with beneficial microbes (biofertilizers) to release nutrients to crops for sustainable production.

Presently the farming situation urges need to develop farming techniques, which are sustainable from environmental, production, and socio-economic points of view. Modern agricultural production throughout the world does not appear to be sustainable in the long run.

Sustainable agricultural development “is the management and conservation of the natural resource base and the orientation of technological and institutional change in such a manner to assure the attainment and continued satisfaction of human needs for the present and future generations”. Such sustainable development in the agriculture, forestry and fishery sectors, conserves land, water, plant and animal genetic resources, is environmentally non-degrading, technically appropriate, economically viable and socially acceptable. Consequently these concerns imparted a way to organic farming. It is the need of the day to understand the prospects and problems of organic farming to launch a successful and flawless organic production programme in the farm environment.

There are many explanations and definitions for organic agriculture but all converge to state that it is a system that relies on ecosystem management rather than external agricultural inputs. It is a system that begins to consider potential environmental and social impacts by eliminating the use of synthetic inputs, such as fertilizers and pesticides, veterinary drugs, genetically modified seeds and breeds, immunity booster preservatives, additives and irradiation. These are replaced with site-specific management practices that maintain and increase long-term soil fertility and prevent pest and diseases.

6.0 General

No lessons can be drawn without the experiences of the past. In fact, much of engineering, rather all sciences have developed in bits and pieces from the experiences of the past. The engineers by and large have never become wiser in one day. They have become wiser slowly and slowly with their own experiences and from the experiences of past engineering works. Wisdom lies to gain wisdom from experiences/draw lessons from the marvellous engineering works constructed so far. It helps us in a direction for further development of technological skills.

Here an effort is made to draw lessons from experiences of the canals constructed in the past.

 There are several aspects of such experiences. A few important aspects of studies are:

 (i) Internal hydraulic sections of the canal with respect to discharge, topography, stability of side slopes, type of lining, operation and maintenance problems and their solutions etc.

 (ii) Design of canals banks (embankment) with respect to discharge, depth of flow, depth of cutting /filling, below/above natural ground level, type of soil, topography, operation and maintenance, drainage of banks etc.

 (iii) Canals aesthetics and arboriculture

 (iv) Other utility/service of canal such as multi-objectives of hydropower, irrigation, drinking/industrial water supply, social needs of recreation, forests etc.

In this chapter, the focus is on understanding the importance of experimental design and being familiar with key terminology. You’ll also learn about the three fundamental principles of experimental design and their roles in conducting experiments. Additionally, you’ll learn how to do randomization of treatments in various experimental designs using R.

Experimental Design

Experimental design is the methodical planning of scientific experiments for reliable results by controlling variables and minimizing biases. It serves as the foundation for effective research. Some key definitions to enhance understanding of this concept:

Key terminologies

• Experiment: Structured investigation for knowledge acquisition or validation.

• Experimental unit: Entity receiving treatment (e.g., land plot, pot).

• Treatment: Specific procedure for assessment and comparison.

• Experimental error: Variation among identically treated units.

Principles of Experimental Design

Experiments are vital tools in agricultural research, aiming to assess treatment effectiveness and quantify their impact. However, extraneous factors can confound results. To mitigate these issues, we depend on three core principles of experimental design: replication, randomization, and local control.

Abstract

Plant roots influence the biological, chemical and physical properties of rhizosphere soil. These effects are a consequence of their growth, their activity and the exudation of organic compounds from them. There is now considerable scope for the new ideas to be extended to the rhizosphere. The role of soil microorganisms in sustainable productivity has been well construed. In recent years, root inhabiting (rhizozosphere) bacteria (rhizobacteria) is gaining importance. The beneficial effects of plant growth promoting rhizobacteria (PGPR) has been variously attributed to their ability in improving the crop production, protection against phytopathogens, soil health and environmental quality. However, there is a need for isolation, identification and improvement of potent PGPR’s to utilize them ultimately as promising bio-inoculants. This review embodies some recent developments to evolve strategies for the better biotechnological exploitation of PGPR’s.

ABSTRACT

Remote sensing, especially high resolution satellite data has a major role to play in locating (localizing) mineral targets. The present study is carried out on exploration and discrimination of magnetite ore deposits of Tirthamalai region of part of Dharmapuri district, Tamil Nadu, India, using IRS P6 LISS IV high resolution satellite data. The applicable image processing techniques and associated put forth of field knowledge is used in the present study. The image processing classifications namely band rationing, principal component analysis and contrast enhancement are carried out in visualizing images using ERDAS Imagine 8.7 software. The visual interpretation of FCC of digital data shows that the raw pixel values of iron ore bands in the blue ranges 95 to 120, green ranges 85 to 125 and red ranges 55 to 75 and provided better delineation for iron formations.

The interpretation of satellite data shows that the iron ore band exhibits in dark color, linear shape, fine texture and sharp contact with associated rock types. To rectify and reduce misinterpretation all above image processing techniques are undertaken along with the detailed filed-check in the selected test sites using GPS 178 and delineated the in situ iron formations. The interpretations show that the occurrence of few more iron bands and weathered formations along with massive formations in the region traced on the imagery since the absorptions themselves are different. The availability spectral absorption of iron formation is inferred highly in visible and near infrared region (0.9-1 Ìm). Remote sensing high resolution satellite data proved that the satellite parameters are important criteria and play a vital role in mapping of low-grade iron ore deposits of the Tirthamalai region of Dharmapuri district of Tamil Nadu state.

Data Collection: An Academic Perspective

Data collection constitutes the systematic gathering and measurement of information pertinent to variables of interest. This process facilitates the answering of research inquiries, hypothesis testing, and outcome evaluation. It is a fundamental component across all academic disciplines, encompassing physical and social sciences, humanities, business studies, and more. While methodologies may diverge among fields, the fundamental objective remains constant: ensuring the precise and ethical acquisition of data. The overarching aim of data collection is to acquire high-quality evidence that underpins robust data analysis, thereby enabling the construction of compelling and credible research outcomes.

Introduction 
Education stands as a fundamental pillar in societal progress and individual development, serving as the cornerstone for a nation’s growth and prosperity. Within the realm of education, the nature of allocation and utilization of public expenditure represent a critical aspect that profoundly influences the quality, accessibility and inclusivity of educational opportunities. As nations navigate through economic, social and technological transformations, the strategic allocation of financial resources towards education emerges as a key determinant in shaping the educational landscape. Today, schools and students are dividing into a world where computers, tablets and the internet play a big role in how we learn. This is a new way of learning called digital education, a cornerstone of the modernization in today’s world. The imperative for digital education arises from the necessity to equip learners with the skills and competencies required to navigate an increasingly interconnected and technology-driven world.Digital tools and technologies offer interactive and engaging learning experiences that cater to diverse learning styles and enable personalized learning systems dedicated to individual’s needs and preferences. Historically, the Northeastern regions had limited access to formal educationdue to its remote and geographically challenging terrain. Colonial rule in India introduced some educational institutions. After India gained independence in 1947, efforts were made to expand education in the region. Various government initiatives, policies and programs like the Rashtriya Madhyamik Shiksha Abhiyan (RMSA) and Sarva Shiksha Abhiyan (SSA) were implemented to enhance education in Northeast India, aimed to provide universal elementary education and improve secondary infrastructure. In recent years, there have been endeavors by both the central and state governments to bridge the educational gap The dawn of the internet era in the 1990s marked a pivotal moment, fostering an environment conducive to the integration of technology into education. Fast forward to the 21st century, the government initiatives like Make in India, Digital India, SWAYAM and National Digital Literacy Mission (NDLM) have proved to be crucial evidence in the significance of digitalization in education.

Abstract

Ever growing population and associated food scarcity are the major issues of concern globally. Microorganisms are the ultimate solution for addressing this severe problem in association with recent advances made in genomics and molecular biology. Many bacterial and fungal species which are in association with plant rhizosphere soil can immensely contribute in better growth and developments, ultimately leading to better yield. Exploring these novel organisms happens to be the need of an hour. Metagenomics and next generation sequencing technologies can contribute in identifying those microbes which are otherwise impossible to cultivate traditionally.

Introduction Extension programmes are strategically planned and implemented by an organization, typically a government department, with the majority of their funding originating from public sources. In the dynamic and ever-changing landscape of developmental initiatives, extension programmes play a pivotal role in fostering progress and transforming societies. These initiatives, designed to extend knowledge, skills, and resources to target communities, are instrumental in addressing pressing challenges and promoting positive change across various sectors. In order to justify the allocation of public funds and to measure effectiveness and sustainability of the programmes, it is imperative to conduct thorough and comprehensive monitoring and evaluations of their administration and impact at regular intervals.