eChapters

Economic System

The three economic problems What, How and to whom to produce are common to all societies or economics. But different countries follow different approaches to solve basic economic problems. These approaches are called economic systems. There are 3 important economic systems.

1. Command economies
2. Market economies and
3. Mixed economies

1. Command economies (Socialist economies): In a system like this, the government controls all aspects of production and distribution. Such a government might be dictatorial or it might be democratic. Main features of socialism are public ownership of means of production, Economic planning, Economic equality, lack of competition, elimination

Heterosis

The superiority of F₁ hybrid over both its parents in terms of yield or some other characters or heterosis is increased vigours, growth, yield or function of a hybrid over the parents, resulting from crossing of genetically diverse organisms. The term heterosis was first coined by Shull in 1914. Generally heterosis manifested as an increase in vigour, size, growth, yield or some other characteristics. But in some cases, hybrid may be inferior to the weaker parent this is also regarded as heterosis.

9.1 Learning Objectives
After completing this chapter, you should be able to:
i) Understand the concept of Sample, Population, Sampling Frame, Sample Size, etc.;
ii) Differentiate between Probability and Non-Probability Sampling methods;
iii) Understand the various methods of sampling;
iv) Recognize Sampling and Non-Sampling errors;
v) Determine Sample Size.

Proper soil management without impairing soil health is the prerequisite for achieving higher productivity from agriculture land. The arable soils of tropics and subtopics are poor in organic matter due to high temperature and intense microbial activity. The importance of organic matter in improving soil fertility through maintenance of optimum levels of soil organic matter as well as plants nutrients is well recognized. There is need to encourage more ecofriendly and productive farming system.

A growing number of farmers, ecologists and scientists are coming to conclusion that conventional farming can not be sustained because in the end it does more harm than good and it is high time to think of sounder ways of farming which are healthy for the soil, environment, plants, animals and human beings.

The practices of economically sound, viable and culturally appropriate agriculture is termed as sustainable agriculture. The excessive and imbalanced use of chemical fertilizers and pesticides on soil and plant in not only harmful to soil microflora and fauna but also reduces the productivity potential of the land. The conventional intensive agriculture has depleted the soil organic matter content and plant nutrients besides the susceptibility of crops to pest and disease. Nitrates the ultimate product of N- fertilizers pollute the ground of water and food, has higher levels of non-protein nitrogen (NPN). Increasing levels of NPN in human bodies have been reported. Soil is a dynamic living system and if it is not manured to feed soil biota, soil health gets deteriorated which is essential for cycling of plants nutrients.

Abstract

Agriculture, which was once a livelihood for millions, is now turning into a not -so-profitable occupation. The interest has reduced especially among the youth because of its input intensive nature. Among all other  things, the most important input in profitable and sustainable agriculture is timely information. However, with the increasing value of the ratio of farmers to extension personnel, getting timely information is a challenge. Then again, rationally used, we are surrounded by communication devices and the most essential and affordable of all are mobile phones. They have made communication easier, faster, affordable and profitable. The boom in mobile based agro-advisory services in the developing countries around the world has found its own subscriber base among the bottom of the pyramid farmers in rural areas and has been developing their economic conditions. Their services range from crop information, market price alerts to holistic agricultural information which are available free of cost and under subscription.

The major components of soil consisting with mineral and organic matter, water and air produces a three phase systems of solid, liquid and gas. Many of the soil properties influencing crop growth and other uses depend mostly on the relative proportions of these components as well as the size, shape and arrangements of the solid matters. The physical properties of soil have strong significance in sustaining agricultural productivity. Fertiliser alone or in conjunction with suitable crop varieties and plant protection measures cannot be sufficient towards improving crop productivity unless the soil physical properties are maintained at satisfactory level. Improvement and restoration of physical properties in soil are necessary for protection of soil resources against degradation. The physical properties of soil discussed in this chapter includes soil densities, texture, structure, porosity and consistency of soils and colour of the soil.

Phosphorus is one of the essential plant nutrients, which is required in optimum amounts for proper growth of plants and soil biota. Being a constituent of ATP it is involved in various processes such as cell division, energy generation and transfer of genetic characteristics and regulation of metabolic pathways (Theodorou and Plaxton, 1993). Phosphorus constitutes about 0.2% plant dry weight (Schachtman et al., 1998). The average soil contains 0.05% phosphorus but only one tenth of this is available to plants due to its poor solubility and chemical fixation in soil (Narayansamy et al., 1981, Barber, 1984). About 98 percent of Indian soils have inadequate supply of available phosphorus (Ghosh and Hasan 1979, Hasan, 1994). A survey of Indian soils showed that out of 363 districts, only 2,2% were high, 51.5% medium and 46.3% were low in phosphorus content (Ghosh 1982).

The problem of P fertilization may become serious in coming years because of the fact that manufacture of phosphatic fertilizers requires the use of non renewable resources such as high grade rock phosphate and sulphur which are becoming costlier. The situation is further aggravated by the fact that P is readily fixed in the soil and the average utilization efficiency of added fertilizer P by plants ranges from 15-25% only (Gaur 1982, 1990). The recent report showed that 42 per cent of soil samples fell in low category, 38 per cent in medium and 20 per cent in high category (Motsara, 2002). It has been observed that the vast alluvial tracts of the country are either low or medium in available P. Hence they need P application at recommended rates.

Abstract

Since pre-historic times plants have tendered their services to mankind in the form of food, shelter and medicine. Due to the advancement of human civilization, various folklore systems of medicines were developed across the globe. Among the various folklore system of medicine, Sowa-Rigpa” is one of the oldest well recognised and widely accepted system of folk-lore medicine in the world. It is one of the commonly used of system of medicine in different parts of Tibet, Bhutan, China, former Soviet Union (some parts), Himalayan ranges, Magnolia and, Nepal. The exact origin of Sowa-Rigpa system of medicine is still not known. In the present scenario due to the awareness among the people about the determental effects of the modern chemical drugs, people preferred to use herbal based system of medicine to treat diseases. So, it is needed to understand the floristic wealth of tradional system of medicine to identify the important plants with potential source of drug candidate molecules. In the present chapter an attempt has been made to study the folklore plants used in Tibetan Mountain based Sowa-Rigpa system of medicine and food. Total 332 plant species presented as the most important in Sowa-Rigpa system of medium.

Among the various natural resources upon which all living organisms depend, soil is the unique because of its non-renewable in nature, heterogeneity in space and time and susceptibility to degradation inflicted by biotic as well as abiotic agents. Whereas, escalating population demands, in one way, to bring more land under the plough for providing food, fodder, fuel and fibre, simultaneously, on the other way, these finite natural resources are dwindling by leaps and bound, through overexploitations and mismanagement, the combined effect of which leads to land degradation, a serious global threat and major environmental issues in the present times.

Introduction
The early human beings undertook extensive exploration of wild species in different plant species before selection followed by domestication for food and other purposes. The identification and selection of innumerable wild plant species and their domestication formed an integral part of early agriculture. Thus the organized cultivation of plant species is the result of selection in and among numerous wild species followed by domestication. It started around 9000-11000 years ago and has given birth to agriculture. The evolution of numerous human civilisations/settlements across the globe is largely shaped by agriculture. Selection continued during domestication which has led to the improvement in the wild plant species and transformed wild plant species into cultivated crop plants. Subsequently, the crop plants were differentiated into distinct landraces depending on morphological features, adaptation, economic use, etc. across different continents on Earth. Selection by humans and/or by nature is a continuous and dynamic process and will continue in future as well. However, a deep understanding of genetic diversity in crop species is essential for successful selection by human beings (Naqvi et al., 2022). The objective of the selection and domestication were dynamic and varied depending on cultural, social, economic and climatic factors. In general, the major objective of selection was to increase yield and bring desirable changes in valuable traits of economic importance. The significance of selection has increased over the years and will continue to increase in future as well. The procedure and methods followed while selecting traits or genotypes of economic importance have led to the birth of a new discipline, plant breeding. In the early years, plant breeding was more of an art than a science. As science progressed, the increased understanding of the genetics of traits complemented plant breeding with scientific back-up. Subsequently, genetics has become the basis of selection, the essence of plant breeding.
Globally, the demand for food, fodder, fuel, energy etc. is increasing continuously and increased crop production is considered as the most viable and sustainable answer or solution. The major driving force for increased demand is the growing population. However, the challenges to increasing crop production are also many namely, the decreasing arable land for agriculture, changing climate (increased extreme temperatures and altered rainfall patterns etc.), decreasing natural resources like water and energy etc. (Razzaq et al., 2021). Further, global warming also impacts the overall agricultural production across crops adversely. In this scenario, the role of plant breeding is vital to sustain higher crop production on a sustainable basis. The responsibility of plant breeders also increases in terms of the development of new, high-yielding, stress (biotic and abiotic) tolerant, high-quality and higher resource use efficient genotypes continually. Historically, conventional/traditional plant breeding has made significant progress in several crops in terms of increasing production, productivity, stress tolerance, nutritional value, etc. Conventional plant breeding relied fundamentally on extensive evaluation of available germplasm for a range of traits of economic importance and utilization of genetic diversity found in the landraces and closely related species (primary and secondary gene pools) (Prohens, 2011; Mangal et al., 2024). The success in conventional plant breeding largely depends on the expertise of breeders while undertaking phenotypic selection. It mainly involved selection within broad genetic base germplasm like landraces, open-pollinated varieties, exploration of wild and related species, and their evaluation for traits of interest, followed by hybridization and cyclical selection (Hallauer and Carena, 2009). The

Chemicals are commonly employed to manage plant diseases, pests, and weeds, but they are only effective if administered promptly once an infestation has been discovered. These chemicals must be sprayed, dusted, or misted over the ground and plants. Since the chemicals are expensive, it is important to have tools for applying them evenly and effectively. Crop Protection Products (CPP) like herbicides, pesticides, and fungicides work best when they are used at the right time during the crop’s most productive times. This problem is getting worse because there aren’t enough people to do the work. In this situation, the only choice that makes sense is to automate the application process. Most of the time, poisons are put on with dusters or sprayers. Dusting is the easier way to apply chemicals. It works best with movable equipment and usually only needs simple tools, but it is less effective than spraying because the dust doesn’t stick around as long. High volume spraying is usually efficient and reliable, but it is more expensive than low volume spraying, which fixes some of the problems with the first two methods while keeping the things that work well about them.

Introduction
In the ever-evolving landscape of agriculture, the intersection of science and technology continually reshapes the way we approach crop improvement. Among the most revolutionary advancements in recent years is the advent of genome editing technologies. These powerful tools offer unprecedented precision and efficiency in modifying the genetic makeup of plants, holding immense promise for revolutionizing the field of plant breeding. Genome editing plays a crucial role in plant breeding by enabling plant breeders to make precise and targeted changes to the DNA of crops, offering significant advantages over conventional breeding methods. Besides, crop improvement, these new breeding tools shorten the time needed to introduce desirable traits into crops, from decades to just a few years. They have revolutionized plant breeding by providing breeders with the ability to efficiently create crops that are more resilient, better adapted, and can produce higher yields with fewer resources, ultimately contributing to sustainable food production and addressing the challenges posed by climate change and population growth.
This comprehensive review aims to explore the transformative potential of genome editing technologies in genetic improvement of crop plants. The review will commence by elucidating the underlying mechanisms of genome editing technologies, offering insights into the molecular machinery that drives precise DNA modifications mediated by ZFNs, TALENs, CRISPR/Cas, base editing, prime editing and other new variants of CRISPR/Cas systems, highlighting their respective strengths and limitations. From enhancing crop productivity and quality to conferring resistance against biotic and abiotic stresses, these technologies offer a versatile toolkit for addressing pressing agricultural challenges. Case studies and examples from recent research will illuminate the successes and potential pitfalls of employing genome editing in crop improvement efforts. Besides, the regulatory and ethical considerations surrounding the deployment of genome editing in agriculture will be addressed. In conclusion, this comprehensive review seeks to provide a holistic perspective on harnessing genome editing technologies in plant breeding. By elucidating the scientific principles, applications, regulatory challenges, and ethical considerations, we hope to facilitate informed discourse and decision-making surrounding the integration of these transformative tools into agricultural practices. As we stand at the precipice of a new era in crop improvement, embracing the potential of genome editing holds the promise of unlocking sustainable solutions to global food security challenges.

1.     Introduction    424

2.    Conventional Methods of Hydrogen Production    426

3.    Biological Methods of Hydrogen Production    429

    3.1.    Hydrogen production by biophotolysis of water, 430
        3.1.1. Photolysis by cyanobacteria (Blue green algae), 430
            3.1.1.1. Nitrogenase dependent hydrogen production, 434
            3.1.1.2.  Hydrogenase-dependent hydrogen production, 437
            3.1.1.3.  Factors affecting  hydrogen production by cyanobacteria, 440
            3.1.1.4.   Bioreactors for cyanobacterial hydrogen production, 443
            3.1.1.5. Future prospects for cyanobacterial hydrogen production, 446

1.    Introduction    496

2.    Strain Development Technologies    496

    2.1.    Screening of natural variants of microorganisms, 496
    2.2.    Genetic manipulation of microorganisms, 498
        2.2.1.    Random mutagenesis and selection, 498
        2.2.2.    Conjugation, 504
        2.2.3.    Transduction, 504
        2.2.4.    Transposition, 506
        2.2.5.      Hybridization, 507
        2.2.6.    Rare Mating, 509
        2.2.7.    Cytoduction, 510
        2.2.8.    Protoplast fusion, 511
        2.2.9.    Transformation, 511
        2.2.10.    Gene cloning and transformation (Recombinant DNA technology), 513

Rainfall, runoff, evaporation, and other hydrological variables exhibit considerable natural uncertainty and therefore cannot be treated as entirely deterministic phenomena. Statistical and probability methods make it possible to organize observations, describe their variability, identify relationships, estimate extreme events, and predict values associated with selected probabilities. Hydrological data may be analysed daily, weekly, monthly, seasonally, or annually and expressed through averages, maxima, minima, dispersion, skewness, and frequency. This chapter introduces statistical terminology, correlation, regression, probability distributions, plotting positions, goodness-of-fit tests, model-evaluation tools, reliability, standard error, and risk analysis. These techniques are essential for flood-frequency analysis, planning, and hydraulic design.

Weed control methods may be classified into two groups as follows:

    1.    Preventive method
    2.    Curative or remedial measures. Curative measures are sub-divided into eradication and control.

(a) Preventive Methods

Prevention is the measures taken to prevent the introduction or spread  of the weeds to new areas and to check the infestation prior to the germination of weed seeds. To achieve this, a wise step to be followed the principle- “Prevention is better than cure”.

History of Genetics

Lamarck (1744-1829): Proposed theory of “Inheritance of acquired characters”.

Charles Robert Darwin (1809-1882): published his classic book “Origin of Species” in 1859 and proposed theory of evolution and survival of the fittest.

Johann Greger Mendel : Gave laws of heredity in 1866 and is considered as Father of Genetics.

W. Flemming: The term mitosis was first used by Fleming in 1882.

W. Waldeyer: Coined the term “Chromosome” in 1888.

August Weisman: Gave the “Theory of Germplasm” in 1889.

This chapter focuses on presenting empirical findings from data analysis to provide sufficient interpretation so to draw reliable conclusions. To enhance and complement the textual contents of the study, tables and models are frequently utilized. Additionally, the discussion serves to contextualize the study’s findings and establish connections with the research work.

The pattern of distribution of the variable, Education (x2 ) depicts that the maximum education of the respondents is 5 and the minimum is 2. The mean value of education of the respondents is 4.09 with standard deviation of 0.82. The Coefficient of Variation is 19.96 per cent which indicates the distribution of variable is highly consistent.

the maximum functional education of the respondents is 15 and the minimum is 2. The mean value of functional education of the respondents is 8.27 with standard deviation of 3.39. The distribution of the variable is fairly consistent with a CV value of 41.06 per cent.

The pattern of distribution of the variable, Size of family (x4 ) depicts that the maximum size of family of the respondents is 9 and the minimum is 3. The mean value of size of family of the respondents is 5.62 with standard deviation of 1.48. The Coefficient of Variation is 26.34 per cent which indicates the distribution of variable is fairly consistent.

The pattern of distribution of the variable, Cultivated Land Holding per capita (x5 ) depicts that the maximum cultivated land holding of the respondents is 1.92 and the minimum is 0.25. The mean value of cultivated land holding of the respondents is 0.77 with standard deviation of 0.30. The distribution of the variable is fairly consistent with a CV value of 38.83 per cent.

the maximum no. of land fragment of the respondents is 2 and the minimum is 1. The mean value of no. of land fragment of the respondents is 1.24 with standard deviation of 0.43. The Coefficient of Variation is 34.73 per cent which indicates the distribution of variable is fairly consistent.

The pattern of distribution of the variable, Avg. size of land fragment (x7 ) depicts that the maximum avg. size of land fragment of the respondents is 1.25 and the minimum is 0.25. The mean value of avg. size of land fragment of the respondents is 0.64 with standard deviation of 0.19. The distribution of the variable is fairly consistent with a CV value of 30.18 per cent.

Biotechnology in the food processing sector targets the selection and improvement of microorganisms, including bacteria, yeasts and moulds with the objectives of improving process control, yields and efficiency as well as the quality, safety and consistency of bioprocessed products. They perform a series of processes such as fermentation, hydrolysis, etc. and even spoilage of food, depending upon the species of organisms, nature of raw material (food), environmental factors (temperature, pH, salt concentration, etc.), duration, etc.

Fermentation
Is the process of bioconversion of organic substances by microorganisms and/or enzymes (complex proteins) of microbial, plant or animal origin. It is one of the oldest forms of food preservation which is applied globally.

Climate change refers to long-term shifts in temperatures and weather patterns. These shifts may be natural, such as through variations in the solar cycle. But since the 1800s, human activities have been the main driver of climate change, primarily due to burning fossil fuels like coal, oil and gas. (https://www.un.org/ en/climatechange/what-is-climate-change) While it is possible to achieve enhanced food production to meet the demands of growing populations, the prevailing negative environmental trends, if continued, might cause crises in many parts of the world (Molden, 2007). The effects of climate change on agriculture can take place through changes in average temperatures, rainfall, and climate extremes (e.g., heat waves); changes in pests and diseases; changes in atmospheric carbon dioxide and ground-level ozone concentrations; changes in the nutritional quality of some foods; and changes in sea level. (Anonymous, 2014A)