eChapters

Site of incision: Make a mid-lateral and mid-medial longitudinal incision on hindlimb from stiffle joint to 3rd digit. Joins the above incisions transversally on caudal aspect at stiffle joint above and 3rd phalanx below, respectively. Remove the skin on plantero-medial aspect of limb.

Site of incision: Make two incisions at mid-lateral aspect at base of the tail join them dorso-ventrally and reflect the skin caudally up the 4-5 inches.

5.1 Introduction

In many problems of economics, we may want to know how small or how large a certain quantity may become. In other words, we may want to know the minimum and maximum values of some functions of variables.

The term ‘optimisation’ may be used in general, both for maximisation and minimisation. The term ‘optimal position’ is often applied to the ‘equilibrium position’ resulting from the balancing of the forces.

6.1 Introduction

Let

v : Represents the volume of a gas.

p : Represents the pressure of a gas.

t : Represents the absolute temperature.

The law is represented by the relation writen as t v k. p ? where k is a constant.

1. Suppose the temperature varies and pressure remains constant then

2. Suppose the pressure varies and temperature remains constant then

7.1 Introduction

The integral calculus is concerned with the opeartion of “integration” which is the reverse process of differentiation. If f '(x) represents the differential coefficient of f '(x), then the problem of integration is to find f(x) from f '(x).

7.2 Integration of a Function Containing a Constant

If we integrate a function containing a constant factor, this factor must also be a factor of final integral.

8.1 Matrix

An arrangement of m×n elements into m rows and n columns is called a matrix. A matrix is a rectangular array of numbers usually represented by enclosing the array in brackets.

Order of a Matrix : The number of rows and columns is called the ‘dimension’ or ‘order’ of the matrix.

14.1 Introduction

In this chapter, we have to present the review matters related to the theory of the “Classical Linear Regression Model (C.L.R.M.) and Testing of Significance of Statistical Hypothesis”. Here, I have to provide the references about the topics and the names of the books from where the readers can refer about the availability of the subject matters (preliminaries, procedures and interpretations) of numerical results obtained through the statistical analysis carried out for the empirical studies considered there in.

In production one or a combination of the following relationship are commonly observed:

1. The law of constant marginal returns (productivity)

 2. The law of increasing marginal returns (productivity)

 3. The law of decreasing marginal returns (productivity)

17.1 Introduction

Factor-factor relationship is concerned with the possibility of substituting one input factor (X1 ) for another input/factor (X2 ) for producing a given level of output. It answers the crucial question of finding out the optimum or least cost combination of two or more resources in producing the given amount of output. The two fold objective of factor-factor relationship is:

18.1 Introduction

The farmers have limited resources and a number of enterprises/or enterprise combinations of crops and livestock to choose from. So, the question is how much of what to produce and with what technology. In other words, what combination of enterprises should be produced is expressed as.

19.1 Introduction

The farm management comprises of two words: ‘farm’ and ‘management’. Literally ‘farm’ means a piece of land where crops and livestock enterprises are taken up under a common management and has a specific boundaries. ‘Management’ means the act or art of managing, the agricultural production or enterprises etc.

23.1 Introduction

The following Frank Kright, the knowledge situation can be classified into the following logical possibilities:

23.2 Perfect Knowledge

There would be no need for farm management experts if knowledge was perfect. If there were so technology, prices and institutional behaviour would be known with certainty for any period of time in the nature. But the concept of perfect knowledge is a fallacious one and does not represent the real world situation.

25.1 Introduction

Farmers must be able to take appropriate decisions at appropriate time. Incorrect judgement and decisions will return in failure of execution of farm plan and in turn economic loss. The farm management decisions can be broadly categorised into two ways.

Disease is one of those terms that are very difficult to define. It is realized that disease (literally dis-ease) implies lack of ‘comfort’and therefore, involves deviation from normal functioning. From time to time several definitions which have been proposed, in fact descriptive but not simultaneously exclusive. The definitions for the term disease are.

Plant Pathogen

Pathogen is an inducer of disease.

A pathogen can therefore be defined as any factor that induces unresolved impairment or disruption of one or more important plant functions.

Some plant functions such as nutrient uptake, are highly localized. Others, such as respiration, occur in all living tissues. Still others, such as photosynthesis and photorespiration, are extensively coordinated. Pathogen effects therefore range from very local to very general.

Disease development depends on three factors: host, pathogen, and environment.

Host must be susceptible.

The pathogen must be virulent to cause disease.

The environment must be conducive to disease development.

Role of environment on disease development 

Environment

Enzymes, toxins, growth regulators, and polysaccharides are much more common and perhaps more important in the development of plant diseases. The pathogen produce these substances when grown on certain substrates (inducible). Let’s talk carefully one by one

Enzymes in plant diseases.

Toxins in plant diseases.

Growth regulator in plant diseases.

Polysaccharides in plant diseases.

Philosophy of defence in plants

Plants cannot move and must resist or tolerate co-located pathogens.

Plants have evolved very powerful preformed defense systems in the form of structural and toxic barriers.

Plants cannot keep intruders out, they can only limit (contain) them.

Plants can tolerate more nutrient runoff. They often sacrifice a piece of tissue to contain pathogens.

Introduction

Plant pathogens include fungi, bacteria, viruses, viroids, phytoplasma, and nematodes.

They have evolved different strategies for invading, feeding on, and reproducing inside plants.

Biotrophic pathogens require living tissue to grow and reproduce.

Necrotic pathogens kill host tissue at the onset of infection and feed on the dead tissue.

Viruses generally require living tissue for survival.

1. Genes and Disease

When various plants such as rice, wheat, tomato and apple are infected with pathogens and cause disease, pathogens are generally different for each host plant type.

Venturia inaequalis, the fungus that causes apple scab, only affects apples. Fusarium oxysporum f. sp. lycopersici which causes tomato wilting, only affects tomatoes and so on.

It is the presence in the pathogen of one or more genes of pathogenicty, specificity, and virulence to the respective host that enables disease development in the host.