eChapters

12.1. BASIC AND CURRENT FACTS OF AGRICULTURE

Basic information related to agriculture and allied sciences in India

1. Cattle
2. Buffaloes
3. Sheep
4. Goat
5. Swine
6. Camel
7. Rabbit
8. Poultry

Animal husbandry

Animal husbandry is the branch of science concerned with the care and breeding of domestic animals such as cattle, hogs, goat, sheep and horses.

India supports nearly 20% of the world livestock and 16.8% human population with a land area of only 2.3%. India leads in cattle and buffalo population and has world’s second largest goat and third largest sheep population. As per the 19^th Livestock census (2012) cattle (191 millions), buffalo (109 m), Sheep (65 m), goats (135 m), pigs (10.29m), camels (0.4 m) and poultry (729.2 m) population was reported in India. The total livestock population has decreased by about 3.33% over the previous census. India’s milk production increased from 43 million tonnes in 1983 to 155.5 million tonnes in 2015-16 (annual growth of 6.27%) and stands first in milk production in world.. The egg production is around 82.93 billion during 2015-16. The per capita availability is around 66 eggs per annum. The poultry meat production is estimated to be 3.26 million tonnes. Wool production (43.6 million Kgs) and meat production is 7.0 million tonnes in 2015-16.

1. Area, Production and Productivity of Horticultural Crops (2013-2014)

9.1. STATISTICAL METHODS

Measures of central tendency : Three measure of the central tendency of a frequency distribution are mean, median and mode.

1. Mean / average / arithmetic mean : It is sum of all of the data values divided by the number of data values and it affected by extreme values.
2. Median : It is the middle value of the data set when it has been arranged in ascending or descending order. This is not at all affected by extreme values.
3. Mode : It is the value that occurs most often in a distribution. Not affected by extreme values. It used to find the ideal size of different age group. eg: size of readymade garments, shoe size

   Harmonic mean : Reciprocal of the arithmetic mean of the reciprocal of a given value. It deals with rate, price and speed.

Measures of dispersion : It is the degree to which the data tend to spread about the mean value is called dispersion.

1. Range : The range of a distribution with a discrete random variable is the difference between the maximum value and the minimum value.
2. Standard Deviation (SD) : It is the square root of the arithmetic mean of the squares of the deviations measures for the mean or square root of the variance.
3. Variance : It is the average of the squared deviation from the mean or the square of the standard deviation
4. Standard Error (SE) : It is the measure of the mean difference between sample estimate of mean (X) and the population parameter (μ).
5. Coefficient of Variation (CV): It is defined as the ratio of the standard deviation to the mean. This is expressed as percentage.

Economics definition

Adam smith (1776) defined economics as the science of wealth in his book An Inquiry into Nature and Causes of Wealth of Nations.

According to Marshall Economics is primarily a study of mankind in the ordinary business of life.

Agricultural Economics : An applied social science that deals with the production, distribution, and consumption of agricultural or farming goods and services.(or) an applied phase of social science of economics in which attention is given to all aspects of problems related to agriculture.

Subject matter of Economics : It can be studied through a) traditional approach and (b) modern approach.

a) Traditional Approach : Economics is studied under five major divisions namely consumption, production, exchange, distribution and public finance.

Consumption : The satisfaction of human wants through the use of goods and services is called consumption.

Production : Goods that satisfy human wants are viewed as "bundles of utility".

Exchange : Goods are produced not only for self-consumption, but also for sales. They are sold to buyers in markets. The process of buying and selling constitutes exchange.

Distribution : The production of any agricultural commodity requires four factors, viz., land, labour, capital and organization. The land owner gets rent, the labourer earns wage, the capitalist is given with interest and the entrepreneur is rewarded with profit. The process of determining rent, wage, interest and profit is called distribution.

Public finance : It studies how the government gets money and how it spends it.

b) Modern Approach : The study of economics is divided into: i) Micro-economics and ii) Macro-economics.

Extension is an “Out – of – School” system of education for rural people.

The term “Extension” have originated in Latin. It means stretching out.

The term “University Extension” was first used in 1866.

The person considered as Father of extension and the concept of Extension Education Process was given by Paul Leagans

The person considered as father of extension in India is K.N.Singh

The term “Extension Education” was first coined in United Kingdom

Extension education is an applied behavioral science and brings about behavioral changes in human beings.

The philosophy of extension is not “What to Think?.” It is “How to think?”

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.

5.1. SEED AND SEED PRODUCTION

Origin of Plentiful Yield is the Seed - Parashara 400BC

Good Seed in Good Soil Yield Abundantly - Manu Smriti 200BC

Botanically seed is a matured ovule containing an embryo in arrested state of development with a food reserve (endosperm) and protective coat (seed coat). In albuminous seeds the endosperm is present eg. rice, wheat, castor (cereals). Whereas, exalbuminous seeds the endosperm is absent eg. onion and pea (pulses).

Types of fruit/ seed

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

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

Soil

Soil is a natural body of mineral and organic constituents differentiated into horizons usually unconsolidated, of variable depth which differs among themselves as well as from the underlying parent material in morphology, physical makeup, chemical properties and composition and biological characteristics (Whitney, 1982; Hilgard, 1892; Dokuchaiev, 1900 and Joffe, 1936).

According to Soil Science Society of America (SSSA, 1970) soil is the unconsolidated mineral matter on the surface of the earth that has been subjected to and influenced by genetic and environmental factors of parent material, climate (including moisture and temperature effects), macro and microorganisms and topography, all affecting over a period of time and producing a product, that is “SOIL” that differs from the material from which it is derived in physical, chemical, biological and morphological properties and characteristics. The unconsolidated mineral material on the immediate surface of the earth, that serves as a natural medium for the growth of plants.

Approaches of Soil Study

Pedological Approach : The origin of the soil, its classification and description are examined in Pedology. (From Greek word pedon means soil or earth). It is the study of soil as a natural body and does not focus on the soil’s immediate practical use.

Edaphological Approach: Edaphology (from Greek word edaphos means soil or ground) is the study of soil from the stand point of higher plants. Edaphologists consider the various properties of soil in relation to plant production.

Soil Science : The science dealing with soil as a natural resource on the surface of the earth, including pedology (soil genesis, classification and mapping) and the physical, chemical and biological and fertility properties of soil and these properties in relation to their management for crop production.

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

A

Acervulus (pl. Acervuli)—A saucer-shaped, spore-producing body of a fungus embedded in host tissue.

Actinomycetes—Filamentous bacteria that produce several antibiotics and give soil its earthy smell.

Active ingredient: In pesticides, the chemical responsible for the desired effect.

Aggressiveness: Virulent forms of pathogen cause differing degrees of symptom severity.

Alternate Host—One of two kinds of plants on which a parasitic fungus (e.g., rust) must develop to complete its life cycle.

Anamorph—Asexual stage of a fungus.

Antagonism: The counteraction between organisms or groups of organisms.

The over emphasis on the use of chemical pesticides and their improper use by the farmers has led to several complications such as residue in food, feed, fodder, development of resistance, resurgence, secondary outbreak, etc. and above all, environmental pollution, leading to a condition known as Pesticide Treadmill characterized by the need to spray ever greater quantities of chemical pesticides. In 1962, Rachel Carson in her book ‘Silent Spring’ aroused worldwide concern about the excessive use of pesticides, which eventually led to the concept of Integrated Pest/Disease Management as an environmentally sound alternative to the sole use of chemicals.

The IDM Concept

In disease management, all the alternate control measures like cultural, biological, mechanical, resistant varieties, physical etc, are utilized in anintegrated manner in order to maintain the disease below economic injury level. If the disease increases and reaches the economic threshold level, pesticides are used to bring the disease down. This is concept of an Integrated Disease Management in which minimum pesticides are used keeping in view of agro- ecosystem. Actually, we do not go for 100 percent control in disease management rather the disease is allowed below which can be tolerated i.e economic threshold. This also provides opportunity for bioagent to survive, managing upon the diseases keeping them at certain equilibrium level. Thus, the Integrated Disease Management concept aims at managing the disease through all the available tactics with favorable economic, social and ecological consequences.

Plant diseases are a threat to world agriculture. Significant yield losses due to the attack of pathogen occur in most of the agricultural and horticultural crop species. More than 70% of all major crop diseases are caused by fungi . Plant diseases are usually handled with applications of chemicals. For some diseases, chemical control is very effective; but it is often non-specific in its effects, killing beneficial organisms as well as pathogens. Chemical control may have undesirable effects on health, safety and cause environmental risks. A promising method for protecting plants against diseases is constructing and employing pathogen-resistant cultivars. Although a number of resistant cultivars have been developed through breeding programs, these cultivars become obsolete in a short time due to the rapid evolution of the phytopathogens and the emergence of virulent forms capable to overcome the plant resistance. Breeders are often confronted with the issue of using a limited number of plants in their breeding programs, undesirable traits transferred together with the valuable resistance genes, and, in recent years, also with the depletion of potential gene sources. Control of diseases is a subject of great interest for biotechnologists. The most significant development in the area of varietal development for disease resistance is the use of the techniques of gene isolation and genetic transformation to develop transgenic resistance to fungal, bacterial and viral diseases. Improvements in genetic transformation technology have allowed the genetic modification of almost all important food crops like rice, wheat, maize, mustard, pulses and fruits. Genetic engineering technology has proved to be beneficial in managing viral and bacterial diseases in plants. The advances in gene engineering technologies and the understanding of the molecular nature of plant protection mechanisms have provided means for developing principally new strategies of plant disease control, in addition to the traditional approaches based on employing chemicals or classical breeding schemes. Biotechnology will enhance our understanding of the mechanisms that control plant’s ability to recognize and defend itself against disease caused by fungi. The integration of biotechnology with traditional agricultural practices will be the backbone for sustainable agriculture.

Proper selection of a fungicide and its application at the correct dose and the proper time are highly essential for the management of plant diseases. The basic requirement of an application method is that it delivers the fungicide to the site where the active compound will prevent the fungus damaging the plant. The fungicidal application varies according to the nature of the host part diseased and nature of survival and spread of the pathogen. The method which are commonly adopted in the application of the fungicides are discussed

1. Foliar or vegetative application
2. Soil application

INTRODUCTION

The use of chemical for protecting plants from the ravages of the pathogens is not an innovation of the 20th century. Chemicals have been used for over 200 years to protect plants against fungal diseases. At present about 150 chemicals belonging to different classes are used as fungicides in world agriculture. Most of the recommended treatments generally provide 90% or greater control of target diseses. Even when a crop has been grown from pathogen free soil and the crop seems superficially healthy, the use of fungicides in some circumstances become unavoidable. Resistant varieties of potato are attacked by late blight if rain occurs during tuber formation. To control this disease use of fungicides become vital to avoid any loss of the crop. Thus, even in the case of resistant varieties, judicious use of chemical protection will extend the life of resistance in the variety. For killing different groups of pathogens, different types of chemicals are required. The chemicals mainly used for controlling diseases are: fungicides for killing fungus, bactericide for killing barteria, nematicides for killing nematodes, and viricides for killing viruses.

INTRODUCTION

The current food crisis has put the agriculture production on a tight leash, not allowing the producers any lassitude whatsoever. Even though we have outgrown from our ‘ship to mouth existence’; our least negligence can torpedo our efforts to maintain the steady state of progress achieved in food grain production. Around 35% of what is produced is lost due to pest and diseases. In this situation, plant protection assumes significance. Unfortunately our plant protection regime begins and ends with pesticides. It is the default option in the plant protection menu and all the other options more or less remain defunct and unused. Even though, our major thrust areas of plant protection are promotion of Integrated Pest Management: ensuring availability of safe and quality pesticides for sustaining food production from the ravages of pests and diseases, streamlining the quarantine measures for accelerating the introduction of new high yielding crop varieties, besides eliminating the chances of entry of exotic pests; we remain largely insulated from these aspects in IPM.

With the Globolization and liberalization in International trade of plants and plant material in the wake of Sanitary and Phytosanitory (SPS) Agreement under WTO, the plant quarantine measures have become more imperative. Liberalization of trade policies have helped the world agriculture trade to prosper which is key sector for many countries like India whose economies are dependent on agrarian industry. But the likehood of the presence of disease/pest inherent in the import material can very well geopardize the trade. Activities are meant to help agricultural development and Plant quarantine service are charged with the responsibility of preventing the entry of hazardous pests, pathogens and weeds, but to deny entry of valuable genetic re-sources would be against national interest. These activities are meant to help agricultural development and they are complementary to each other and therefore are necessary, and we on our parts need to be fairly vigilant. As has been very truly said-An ounce of prevention is worth a pound of cure.