eChapters

As we know there are different branches of artificial Intelligence and machine Learning of one of them which has become a most advance and widely used branch of artificial Intelligence in every field of this generation whether it may be either electronics, civil, mechanics, Bioengineering, medical or agriculture etc., In this chapter we will study about machine learning and its types with the most common algorithms of machine learning which are being mostly used in different scenarios and their implementation using python language has been discussed in the implementation part of this book. Here we will also see where machine learning can be used.

i. Introduction

Machine learning is a subset of Artificial Intelligence and one of the most important part of artificial Intelligence. It is a field of Computer science which is totally differs from traditional computational approaches. In traditional approaches, a set of instruction is explicitly provided to the algorithm to solve any problem. Whereas in Machine Learning is a domain of an AI which uses a statistical analysis and can enables a system to always learn from its data without any external inputs in order to give an essential output. Due to this machine learning makes computers in advance to make model which provide decision based on input data.

Machine Learning involves a lot of algorithms which usually based on their requirements and functionalities to use where and when. To make a machine learning model we always require the data on which model can be made. Machine learning uses the algorithm which continuously learns from the data available as training data. A machine learning model is generated after the training of algorithm from the data. After the training completes, when trained model is provided with other real-life data then you can get an essential outcome. For example, in figure 3.1 Machine learning Model we use a predictive algorithm and make a model by providing it with some data, and later on we can receive prediction’s based on real data as input.

As we have seen how artificial Intelligence can be useful in agriculture but the nest question always come in mind is that from where and how we can start to learn and what are the model of learning an artificial Intelligence. As Artificial Intelligence is a huge part of Computer Science which means we need an language as medium to perform it and we always prefer Python for that which is very dynamic and easy to learn. In this chapter we will learn about python basics so that in further implementation of artificial Intelligence it will be helpful to us.

I. Introduction

Python is a remarkable language that can claim to be easy and strong. You will be amazed to see how simple it is not to focus on the language you are programming, but on solving the problem. Guido van Rossum was the creator of the Python language which is named after the BBC show “Monty Python’s flying Circus”.

Python is formally introduced as:

“Python is an easy to learn, powerful programming language. It has efficient high-level data structures and a simple but effective approach to object-oriented programming. Python’s elegant syntax and dynamic typing, together with its interpreted nature, make it an ideal language for scripting and rapid application development in many areas on most platforms.”

The artificial intelligence (AI) world is quickly growing as it reaches several different industries. You currently will see AI used for many different purposes from agriculture to automotive; with the passage of time you will see even more of it. Agriculture is one of the most important branches of the IT industry. Agriculture is an important industry and is a big part of our economy’s base. In terms of annual sales, the agricultural industry contributes to our economy almost 17%.AI is becoming a technical advancement that boost and protects crop yield, as climate change and populations rise. Here in this chapter basics of Artificial Intelligence have been discussed how it can be related to agriculture.

1. Introduction

Artificial Intelligence has become most prominent in current generation. Every field is utilizing Artificial Intelligence for their better results and which also result in saving a lot of time. As Artificial intelligence is boosting different sectors to increase the productivity and efficiency and its utilization across different sectors like in the field of CIVIL Artificial Intelligence can be used to analyze the structures of buildings, dams etc., and Artificial Intelligence solutions are assisting in so many ways to overcome the traditional challenges in every field.

I. What is Artificial Intelligence

Artificial Intelligence is one of the most prominent field of Computer Science Engineering which attempts to redefine the tasks which are carried out by humans in their daily life with better results and maximum accuracy. Artificial Intelligence is actually meant to ease the work of human where the word artificial states the work done without any human interference and intelligence states the capabilities like human brain to perform tasks. The field artificial Intelligence has given so many definitions from time to time which can be typically stated as

10.1 Introduction

Biomass fuels are a potential source of renewable energy. One of the major barriers to their widespread use is that biomass has a lower energy content than traditional fossils fuels, which means that more fuel is required to get the same amount of energy. When combined — low energy content with low density -the volume of biomass handled increases enormously. Compaction or densification is one way to increase the energy density and overcome handling difficulties.

Densification means compaction of loose material or to increase density of loose biomass so that its volumetric efficiency can be increased. Densification essentially involves two parts; the compaction under pressure of loose material to reduce its volume and to agglomerate the material so that the product remains in the compressed state. The resulting solid may be a briquette, a pellet and a cube. It will be briquettes if roughly, it has a diameter greater than 30 mm. Smaller sizes are normally termed pellets though the distinction is arbitrary. The process of producing pellets is also different from the typical briquetting processes. The densified product can be developed in the cubical shapes as well.

If the material is compacted with low to moderate pressure (0.2-5 MPa), then the space between particles is reduced. Further, increasing the pressure will, at a certain stage particular to each material, collapse the cell walls of the cellulose constituent, thus approaching the physical, or dry mass and more, density of the material. The pressure required to achieve such high densities are typically 100 MPa plus. This process of compaction is entirely depending on to the pressure exerted on the material and its physical characteristics including its moisture content.

9.1 Introduction

The rapid growth of industrialization and population significantly affect on the demand of ethanol as an alternate fuel. Generally, conventional crops like sugarcane and corn become unable to meet the demand of bioethanol, due to their primary role in food and feed. Therefore, lignocellulosic biomass from agriculture waste is attractive precursor for bioethanol production. Biomass is renewable organic material, abundant and cost effective. Ethanol production from agriculture waste has been projected an economically attractive option for industrial sector. However, sugar and starch derived ethanol have a more theoretical yield as compared to lignocelluloses, theses sources are insufficient for bioethanol production. The major agricultural wastes including rice straw, corn straw, wheat straw and sugarcane bagasse etc. can subsequently used for ethanol production. Rice straw has a highest worldwide potential for bioethanol production (205 giga liter) followed by wheat straw (104 giga liter), corn straw (58.6 giga liter), and finally for sugarcane bagasse (51.3 giga liter)¹.

A bio fuels is environmentally friendly options for power generation. Most of the fossil fuels are biological in nature. These are plant forms that, typically, remove carbon dioxide from the atmosphere and give up the same amount when burnt. The bio fuels are therefore considered to be “CO₂ neutral”, not adding to the carbon dioxide level in the atmosphere. The type of bio fuel used will depend on a number of factor, chief amongst them being the available feedstock and the energy that can be used locally.

India import 70% of the oil it uses, and the country has been hard by the increasing price of oil, uncertainty and environmental hazards that are concerned with the consumption of fossil fuels. In this context, bio fuels constitute a suitable alternative source of energy for India. There are two examples of bio fuels are Ethanol and Bio diesel (Renewable Diesel)

Ethanol can be made from biomass material containing sugar, starches, or cellulose (starch and cellulose are complex from of sugar)

8.1 Introduction

Rising petroleum prices, increasing threat to the environment from exhaust emissions and global warming have generated an intense international interest in developing alternative non-petroleum fuels for engines. The use of vegetable oil in internal combustion engines is not a recent innovation. Rudolf Diesel (18581913), creator of the diesel cycle engines, used peanut vegetable oil to demonstrate its invention in Paris in 1900. In 1912, Diesel said, “The use of vegetable oils as engine fuel may seem negligible today. Nevertheless, such oils may become, in the passing years, as important as oil and coal tar presently.” Nowadays, it is known that oil is a finite resource and that its price tends to increase exponentially, as its reserves have being decreasing¹.

India ranks sixth in the world in total energy consumption and needs to accelerate the development of the sector to meet its growth aspirations. The country, though rich in coal and abundantly endowed with renewable energy in the form of solar, wind, hydro and bio-energy has very small hydrocarbon reserves (0.4 % of the world’s reserve). India, like many other developing countries, is a net importer of energy, more than 25 percent of primary energy needs being met through imports mainly in the form of crude oil and natural gas. The rising oil import bill has been the focus of serious concerns due to the pressure it has placed on scarce foreign exchange resources and is also largely responsible for energy supply shortages. The sub-optimal consumption of commercial energy adversely affects the productive sectors, which in turn hampers economic growth².

7.1 Introduction

Biomass gasification is age old technology originated in 1800 century for lighting and cooking purposes (Sansaniwal et al., 2017). Biomass typically contents biopolymers such as cellulose, hemicellulose and lignin in addition to the presence of average composition of C₆H₁₀O₅ which depends upon physical characteristics of biomass¹. Oxygen is required for combustion of every fuel. For complete combustion of biomass stoichiometric air to fuel ratio required varies from 6:1 to 6.5:1 with CO₂ and H₂O as end product.

Biomass gasification is an efficient and environmentally friendly way to produce energy². Gasification process is nothing but it is a conversion of solid fuel into gaseous fuel for wide applications. This whole process completed at elevated temperature range of 800-1300 ^oC with series of chemical reaction that is why it come under thermo chemical conversion³. Thermo chemical processes are most commonly employed for converting biomass into higher heating value fuels⁴. Major thermal conversion route is include direct combustion to provide heat, liquid fuel and other elements to generate process heat for thermal and electricity generation is summaries in Fig. 7.1.

6.1 Introduction

Torrefaction is a thermophilic process of biomass conversion into a solid, friable, homogenous coal-like material, which has better fuel characteristics than the original biomass. Torrefaction involves the heating of biomass material in the absence of air at 250 to 300°C temperature. Torrefaction produces high-grade hydrophobic nature solid biofuels from various streams of woody biomass or agro residues.Torrefied biomass has high energy density then the original biomass which make torrefied biomass as renewable alternate source for power generation in coal power plant. Torrefied biomass being hydrophobic in nature can be stored easily for longer duration with negligible biological degradation. At 250-300°C temperature volatilization has been taking place and around 30% mass of the biomass is reduced as compared to original untorrefied biomass with net energy loss of approximately around 10%.The end product is a predictable, homogeneous, hydrophobic, high value solid biofuel with far higher energy density and calorific value than the original biomass feedstock. During the torrefaction process a combustible gas is released, which can also utilised to provide heat to the process. The process diagram of torrefaction process is shown in Fig. 6.1.

5.1 Introduction

Today, energy distribution and environmental issues have developed into international threats. Demand for alternative fuels increases every day due to rapid population growth, rising living standards, and economical sustainability. With its massive population, India has become the fourth largest energy consumer country in the world after the United States, China, and Russia. Because most nations use fossil fuels to fulfill their energy demands, they create negative impacts on the environment including raising global temperatures, pollution, acid rain, and other effects. As such, the quest for alternative fuels derived from renewable resources has captured significant attention throughout the world¹. Biomass as a renewable energy sources is an important asset for achieving economic development is due to the availability of biomass at a low cost, a good conversion efficiency, the addition of jobs, and an increase in the biodiversity^2,3. Typically, biomass is composed of cellulose (40-50%), hemicelluloses (25-35%), and lignin (15-30%). Large amount of resources for biomass are available such as woody biomass, crop residues and their by-products, food processing waste, municipal solid waste, aquatic plant etc.

In the present context, pyrolysis process has been received a remarkable identity as a potential method for the conversion of any organic biomass into valuable energy rich products due to its simple in operation and also required a reasonable cost for conversion process. Pyrolysis is the thermal decomposition of any organic material at a specific temperature in absence of air/oxygen; the process ends with three resulting products, namely liquid (bio-oil), solid (biochar), and syngases⁴. Recently, biooil produced through pyrolysis process and further it up grading has been attracted a significant attention due to its major use as biofuel and as a precursor material for making chemicals⁵. The pyrolysis process also classified in three different types as per its operating conditions; slow, fast and flash pyrolysis.

4.1 Introduction

Biomass is referred to as an indirect source of solar energy and considered a source of stored chemical energy. Biomass is renewable organic material derived from plants and animals serving as sources of energy. Biomass produced from agricultural sector is big challenges for all over the world due to its improver disposal. Mitigating greenhouse gas emissions and ensuring adequate global food supplies represent two of the last decade’s mostdifficult challenges.Although global food production has benefitted from chemical fertilizers, environmental problems have emerged as a result of their use. Additionally, overuse of fertilizers can result in hardened soil, decreased soil fertility, polluted air and water, and the release of greenhouse gases. There is an urgent need to find an alternative to chemical fertilizers that, ideally, can be sourced in abundant amounts, promotes global food production, enhances CO₂ capture , and does not affect soil health or damage the environment¹. To sustain agricultural productivity, it is crucial to maintain adequate levels of organic matter in the soil to preserve its physical, chemical, and biological integrity. Biochar, a pyrogenic black carbon, may play an important role in improving soil health, resulting in higher crop yield and absorbing atmospheric carbon dioxide. Biochar is the most auspicious straw management measures and have highest carbon abatement and economic profit².

Biochar is produced by heating biomass at high temperatures (300 – 600 °C) in a closed reactor containing no to partial levels of air. Under these conditions, biomass undergoes thermo-chemical conversion into biochar. Because of its numerous potentials uses in agriculture, energy, and the environment, much attention has been given to biochar in both political and academic areas. Biochar can be used in a variety of applications such as energy production, agriculture, carbon sequestration, waste water treatment, and bio-refinery; additionally, biochar provides an alternative strategy for managing organic waste. These advantages have renewed the interest of agricultural researchers in producing biochar from bio-residues and using the product as a soil amendment.

3.1 Introduction

Nature has a provision for destroying and disposing off wastes and dead plants and animals. This decay or decomposition is carried out by tiny micro-organisms called bacteria. Making of farm-yard manure (FYM) and compost is also through decomposition of organic matter (OM). When a heap of vegetable or animal waste and weeds etc., die or decompose at the bottom of backwater or shallow lagoons, bubbles can be noticed rising to the surface of water. Sometimes these bubbles burn with dancing flame at dusk. This phenomenon has puzzled man for a long time. It was only during the past hundred years that Scientists unlocked this secret as the decomposition process. The gas thus produced was and is still called “Marsh Gas.” The technology of harnessing this gas under artificially created conditions is known as Biogas Technology.

2.1 Introduction

Biomass store solar energy in the chemical form and it is most precious and versatile resources on earth. Biomass, unlike fossil fuels, is a renewable energy resource that is available where the climatic conditions are favorable for plant growth and production¹. The term biomass is used for all organic materials which are combustible in nature, mainly plant and animal origin present in land and aquatic environments. Biomass is considered carbon neutral, because the amount of carbon it can release is equivalent to the amount it absorbed during its life time. There is no net increase of carbon to the environment in the long term when combusting the lignocellulosic materials. Therefore, we can say that biomass is a renewable source of energy and can play vital role in responding to concerns over the protection of the environment and the security of energy supply^2,3.

Biomass energy accounts for about 15% of the world’s primary energy consumption and about 38% of the primary energy consumption in developing countries⁴. Furthermore, biomass often accounts for more than 90% of the total rural energy supplies in developing countries⁵. It is the main source to meet out domestic energy in developing countries⁶. The efficient use of fuel wood is much more eco-friendly than the use of efficient and conventional fuels like kerosene and liquefy petroleum gas (LPG). LPG emits 15 times more CO₂ per kg than wood, and kerosene emits nearly 10 times as much. CO₂ is the prominent candidate for global. It is commonly assumed that biomass fuel cycles based on renewable in nature and greenhouse-gas (GHG) neutral because the combusted carbon in the form of CO₂ is soon taken up by re-growing vegetation⁷.

1.1 General

The term “biomass” generally refers to renewable organic matter generated by plants through photosynthesis. Materials having organic combustible matter is also referred under biomass.Biomass is an important fuel source in our overall energy scenario. Biomass is produced through chemical storage of solar energy in plants and other organic matter as a result of photosynthesis. During this process conversion of solar energy in sugar and starch, which are energy rich compounds takes place. The chemical reaction of photosynthesis can be written as:

6CO₂ + 6H₂O + sunlight → C₆H₁₂O₆ + 6O₂ + 636kcal

It indicates that the storage of 636 kcal is associated with the transfer of 72 gm carbon into organic matter. Biomass can be directly utilized as fuel or can be converted through different routes into useful forms of fuel. In fact, biomass is a source of five useful agents, which start with ‘F’ like food, fodder, fuel, fiber and fertilizer. Further, biomass has many advantages like.

(1) It is widely available

(2) Its technology for production and conversion is well understood.

(3) It is suitable for small or large applications

(4) Its production and utilisation requires only low light intensity and low temperature (5 to 35°C)

(5) It incorporates advantage of storage and transportation

(6) Comparatively, it is associated with low or negligible pollution.

An area with similar soil, climatic conditions and resource availability resulting in similar type of crops and cropping systems. Ex. Rice based cropping system, Ragi based cropping system, Wheat based cropping system, Cotton based cropping system etc.

Efficient cropping zone: An analysis of productivity efficiency of crop was made by Kanwar (1972) using relative yield index (RYI) and relative spread index (RSI).

A zone where both yield and spread indices are maximum that is above 90 per cent is called most efficient and in case of indices below 90 is the least efficient zone of a crop.

Agriculture is the most important sector in India in terms of the population dependent on it. Although agriculture now accounts for on 14 per cent of GDP, it is still main source of livelihood for the majority of the rural population. Rapid growth of agriculture is critical for development of rural economy and viable development of rural economy will leads to overall development of country. Diversification in agriculture is need of the hour, any cropping system comprising crops with varied maturity period, crop canopy and high yielding potential is need for an average farmer. Again cropping systems depending upon the soil type, total rainfall and arrival of monsoon in the region. Low cost technology is essential for reducing financial burden on farmers and to increase production on sustainable manner.

The crop production is affected by the plant type, climatic condition, soil type and management factors. The production of the plant might be increased by changing plant type and increasing the grain filling period under certain climatic condition where management and soil factors are not limited. There is a direct relationship between the plant type and crop yield because the orientation and number of leaves play an important role in carbon fixation (photosynthesis). Again any variety/cultivar will contribute 21-25 per cent to the total yield of any crop in general. In recent years due to development of photoinsensitive varieties and hybrids which are more fertilizer responsive and high yielding varieties lead to increase overall production in the country.

Plant ideotypes

Refers to plant type in which morphological and physiological characteristics are ideally suited to achieve high production potential and yield reliability. The concept of ideotype was given by Donald in 1968 and he illustrated that there should be minimum competition between the crops and crop must be competent to compete with weeds. Ideotype is defined as a biological model which is expected to perform or behave in a predictable manner within a defined environment. On the basis of environment, Donald and Hamblin (1976) identified two forms of ideotypes that is isolation ideotypes and competition ideotypes. Isolation ideotypes are suitable for mono/single cropping and competition ideotypes are suitable for mixed cultivation.

Crop diversification refers to the addition of new crops or cropping systems to agricultural production on a particular farm taking into account of the different returns from value-added crops with complementary marketing opportunities.

Major driving forces for crop diversification

Crop diversification provides better conditions for food security and enable farmers to grow surplus products for sale at market and thus obtain increased income to meet other needs related to household well being. Crop diversification enable farmers to gain access to national and international market with new products, food and medicinal plants. Diversification from the monoculture of traditional staples are important for nutritional benefits of farmers in developing countries and can support a country to become more self reliant in terms of food production. Diversification also manages price risk and compared to monoculture techniques. For diversification crops generally consists of more sustainable natural resources and again, diversified farms are usually more economically and ecologically resilient.

The stability of yield is an important characteristic to be considered when judging the value of a cropping systems when compared to others cropping systems. Here, we focus on multiple cropping and how this agroecological practice can be used to increase the sustainability of crop production. Strip, mixed and relay intercropping can be used to increase crop yields through resource partitioning and facilitation. In addition to achieving greater productivity, diversifying cropping systems through the use of strategic cropping systems will increase yield stability, reduce weeds, pests, disease and improve soil health. Several multiple cropping systems are already implemented in industrialized agricultural landscapes, including mixed intercropping with perennial grasses and legumes as forage and relay intercropping with winter wheat and red clover. Because multiple cropping systems will provide numerous benefits, researchers should be clear about their objectives and use appropriate methods so as not to draw spurious conclusions when studying multiple cropping systems. In order to advance the practice, experiments that test the effects of multiple cropping systems should use standardized methodology and researchers should report a set of common criteria to facilitate cross-study comparisons. Multiple cropping systems with two or more crops appears to be less common with annuals than perennials, which is likely due to differences in the mechanisms responsible for complementarity. One area where intercropping with annuals in industrialized agricultural landscapes has advanced is with cover crops, where private, public and governmental organizations have harmonized efforts to increase the adoption of cover crop mixtures.

When crops are grown in either intercropping or sequential cropping interaction between different component crops occurs which is essentially a response of one species to the environment as modified by the presence of another species is commonly referred to as interference or interaction.

The interaction are classified into three groups

1. Competitive interaction: One species may have greater ability to use the limiting factor and will gain at the expense of the other and this is called competitive interaction or when one or more growth factors are limiting, the species that is better equipped to use the limiting factor(s) will gain at the expense of the other and this is called competitive interaction.
2. Non competitive: If the crops are grown in association and the growth of either of the concerned species is not affected, such type of interaction is called non competitive interaction or if resources (growth factors) are present in adequate quantities, as a result of which, the growth of either of the concerned species is not affected, then it is non-competitive interaction or interference.
3. Complementary: If one species is able to help the other, it is known as complementary interaction or if the component species are able to exploit growth factors in different ways (temporal or spatial) or if one species is able to help the other in supply of factor (like legumes supplying part of N fixed by symbiosis to non-legumes), it is complementary interaction or interference and also referred to as Annidation.

Various types of cropping systems are practiced in a farm or region. They should be evaluated to find out their stability and relative advantages in yield. Again, comparisons may be made with reference to land use efficiency, biological potential and economics. Following are the important indices for assessment of competition and yield advantage:

1. Relative yield total (RYT): The oldest establishment measure of the yield advantage of crop mixtures is the Relative Yield Total. The RYT index was designed as a measure of the extent to which various crop components shared common resources, rather than as a direct measure of yield advantage.

Classifications of cropping systems

Depending on the resources and technology available, different types of cropping systems can be adopted on farms and which are as below.

Mono cropping /single cropping: Mono cropping refers to growing only one crop on a particular land year after year or practice of growing only one crop in a piece of land year after year. Example, growing only crops during kharif in rainfed areas and this is due to lack of irrigation facilities and crops depend on rainfall alone.

In sustainable agriculture the word sustain is derived from the Latin word sustinere (sus-from below and tinere-to hold), to keep in existence or maintain, implies long term support or performance. As it pertain to agriculture, sustainable describes farming system that are capable of maintaining their productivity and their usefulness in society indefinitely. Such system should be resource conserving, socially supporting, commercially competitive and environmentally sound. Systems approach is essential for understanding sustainability and it gives us tools to explore the interconnections between farming and other aspects of our environment and sustainability implies at the following,

1. Meeting the basic needs of all people and giving this priority over meeting the greeds of a few
2. Keeping population densities if possible below the carrying capacity of the region
3. Adjusting consumption patterns and the design and management of systems to permit the renewal of renewable resources
4. Conserving, recycling and establishing priorities for the use of non- renewable resources
5. Keeping environmental impact below the level required to allow the systems unaffected to recover and continue to evolve.

Various definitions have been provided for what constitutes sustainable agriculture ranging from the narrow focus on economics or production to the incorporation of culture and ecology. Wendell Berry has simply said A sustainable agriculture does not deplete soils or people.

Multiple cropping includes both inter and sequential cropping systems and here the main objective is to utilize the available resources effectively in a given environment. Number of indices are available for assessing land use and the yield advantage of crop mixtures compared to pure stands. These indices not only reflect the difference in criteria used to appraise advantages often encompassing aspects of quality or values as well as yield, but also reflects the different reasons for which an assessment is made.

1. Rotational intensity (RI): Crops are grown in a recurring sequence on the same piece of land with sufficient diversity and intensity. Crop rotations to control erosion/ to improve or maintain soil fertility and to manage weeds, insects and disease. Lower values of rotational intensity indicate mono cropping and higher values of rotational intensity indicates more rotation.

The main objective of any cropping system is to utilize available resources efficiently viz., land, water, solar radiation by maintaining stability in production in order to obtain higher net returns. The efficiency is measured by the quantity of produce obtained per unit resource used in a given time. The objective of traditional agriculture was to increase the production by two means

1. By increasing area under cultivation
2. By increasing the productivity per unit area of the crop

But two more dimensions are added to modern agriculture

1. To increase the production per unit time
2. To increase the production per unit space

In the traditional cropping systems, mixtures and rotations were developed by the farmers over years of experience by trial and error to suit specific ecological and sociological conditions to attain yield stability, whereas modern scientific cropping has three pillars viz.

A system is a unit which possess a group of interacting components, operating together for a common purpose, capable of reacting as a whole to external stimuli. It is unaffected directly by its own outputs and has a specified boundary based on the inclusion of all significant feedbacks. For example, the human body is a system-it has a boundary (skin) enclosing a number of components (heart, lungs) that interact (the heart pumps blood to the lungs) for a common purpose (to maintain and operating the living body).

Ecosystem: Any collection of organisms that interact or have the potential to interact along with the physical environment in which they live form an ecological system or ecosystem. Ecosystems are not static entities but, they are dynamic systems with characteristic pattern of energy flow, nutrient cycling and structural change.

Agro ecosystem: Agro ecosystems are ecological systems modified by human beings to produce food, fibre or other agricultural products. Like the ecological systems, agro ecosystems are structurally and dynamically complex. But their complexity arises from the interaction between socio economic and ecological processes.

Crop system: An arrangement of crop population that transform solar energy, nutrients, water and other inputs into useful biomass that produce food, feed, fuel and fibre. Crop system comprise of soils, crop, weed, pathogen and insect subsystems. The crop can be of different species and variety, but they only constitute one crop system if they are managed as a single unit.

Cropping systems: It is defined as the order in which the crops are cultivated on a piece of land over a fixed period of time. Cropping system is the way in which different crops are grown. In the cropping systems, sometimes a number of crops are grown together or they are grown separately at shorter intervals in the same field.

Growing more than one crop in sequence or simultaneously as a mixed crop is an ancient practice. In Indian Vedas, there is a mention about double cropping. In early periods, the objective to adopt sequential cropping practices was to reduce the risk of total crop failure due to uncertain monsoon and to have a variety of produce to meet food requirement of farmer’s family, fodder to animals and to meet his cash requirements. Other benefits of yield increase was due to complementary effects of the component crops in improving the soil fertility, spreading the labour requirement throughout over a period of time and to reduce damage caused by weeds, pests and diseases were only incidental.

Multiple cropping in simple terms refers to the practices that increase production in a unit area of land through two or more growing crops simultaneously. The importance of intensive cropping in sustainable agriculture has been well understood by the agricultural scientists of late and there has been surge of interest in the research community to explore these complex systems in detail and to see what can be learnt from the farmers in our quest to make cropping system more sustainable progress made in the past through intensive research carried by the various agricultural universities, ICAR, research institutes/ coordinated research projects and international research institutes such as IRRI, ICRISAT, IITA and CIMMYT, it has shown that and more efficient utilization of the natural resources is possible by suitably modifying the present cropping systems in the various regions of the world.

The present cropping intensity in India is 136 per cent. There is a great prospect for increasing the cropping intensity both in irrigated and rainfed areas. In many irrigated areas, cropping intensity can be increased to 200-300 per cent. There is good scope to increase cropping intensity to 180-200 per cent with proper policies and technology options in rainfed conditions also.

Abstract

Anaerobic microorganisms occur in oxygen-free environments as they possess biomolecules and metabolic processes that have adapted to sustain them in the stressed environments. These biomolecules and metabolic processes are harnessed and employed in various biotechnological applications. Anaerobes are abundant in various ecological niches such as freshwater or marine sediments, subsurface aquifers, deep thermal vents etc. where, in the absence or limitation of oxygen, they utilise reduced ions such as nitrate, sulphate, ferric, carbonate and certain organic compounds like degrading organic matter, fatty acids or alcohols as electron acceptors during respiration/fermentation to produce more or fewer reduced products such as, alcohols, ammonia, organic acids, hydrogen and carbon dioxide as the oxidised product. Diversity of substrates that can be fermented and the wide range of products that can be formed make anaerobic processes useful in biotechnological applications. Their substrate versatility and flexibility, for example, they can utilize simple sugars as well as many of them can utilise complex renewable biomass make their biotechnological applications sustainable and environment friendly. Anaerobes have been employed in food, chemical and material industries for the production of food items, preservative, additives, chemical intermediates, solvents, catalysts and polymers. They find widespread usage in energy sector for generation of various kinds of biofuels that can mitigate our reliance on non-renewable sources for fuel production. An emerging aspect of anaerobic biotechnology is waste valorization that involves treatment of any kind of waste (industrial, municipal, agricultural, pharmaceutical), where organic fraction of the waste is converted into valuable products. Anaerobes play key role in maintaining the global cycles of carbon, nitrogen, and sulfur, and also facilitate bioremediation by breakdown of persistent compounds. Lately, role of anaerobes in medicine and health care sector is widely explored as they are found to produce several bacteriocins, antibiotics, immunomodulators, vitamins and anti-tumor compounds. Some of the anaerobes have also been employed as probiotics. In the present chapter, we discussed these and many more biotechnological applications of anaerobes in white, green, red and blue biotechnology.

Abstract

Hundreds of bacterial taxa makes up human gut microbiota and it is comprised primarily of anaerobes belonging to four main phyla which are Firmicutes, Bacteriodetes, Actinobacteria, and Proteobacteria. Anaerobes colonizes the human body, including oral cavity, small intestine, vagina, skin but the majority of them are housed in the colon. The composition and distribution anaerobes varies along the length of gastrointestinal tract because of variation in oxygen gradient, anatomy of intestinal tract and other host physiological factors. Human gets colonized by anaerobes during the birth and these initial colonizers have impact on infant’s health status. The colonization and development of the gut microbiome is responsive to variety of factors including the mode of delivery, feeding methods, environment etc. The human gut microbiota plays an important role in healthy status of host. It plays an important role in nutrient metabolism and absorption, synthesis of vitamins and production of short-chain fatty acids (SCFAs). In turn these metabolites have positive effect on host immunity and overall host fitness. Studying, the anaerobes using culturing method remains critical in microbiology. However, culturomics approach, combined with sequencing technology, provides new insights in studying anaerobes of human gut microbiota. In this chapter we have discussed that, how human gut is an ideal habitat for the colonization and growth of anaerobes and their impact on host health. We also tried to shed light on latest technical advancement in sequencing culturing technology and their application in studying gut anaerobes.

Abstract

Gastrointestinal tract (GIT) harbors mixed microbial community, these are highly diversified, as revealed by molecular and phylogenetic studies. It is also estimated that microbiota of the GIT is composed of over 35,000 species and play a crucial role in human health and diseases. Thus are now of great interest to both the industrial and scientific communities. The microbes exhibit health benefits are known as probiotics. Anaerobic bacteria dominate in the GIT environment and genera like Bifidobacterium, Clostridium, are strict anaerobes while Lactobacillus, Lactococcus, is facultative anaerobes implicated in the probiotic effects.

For developing anaerobic bacterial based bio-products, it is necessary to cultivate large-scale biomass production that could be done using a modern manufacturing practice. Information on detailed understanding of the perfect growth medium and other bioprocessing parameters for the growth and viability is must. Also high cell viability is a prerequisite during downstream processing and storage of probiotic formulation. In this work we review the latest information about the history, mechanism of action, benefits of probiotic, selection criteria, sources of anaerobic probiotic bacteria, industrial cultivation medium along with biomass production, downstream processing.

Abstract

The normal human microbial flora comprises of both aerobes and anaerobes at various sites. Anaerobes are recognised as pathogens causing simple abscesses to life threatening human infections like gas gangrene. They are also incriminated in a large number of mixed bacterial infections and their diagnosis and specific therapy is important for better patient outcomes. The emergence of Clostridioides difficile as an important pathogen causing antibiotic associated diarrhoeas and its emerging resistance to antimicrobial agents has brought anaerobic microbiology into the forefront. Unfortunately, anaerobic clinical microbiology is difficult to practice with long turnaround time, difficult to grow pathogens, new genera and species being discovered based on 16S rRNA sequencing methods and increasing incidence of antimicrobial resistance being reported in anaerobes. This chapter delves into the important aspects required to improve utilization of anaerobic microbiology services and the variety of human infections we encounter in clinical practice due to anaerobic bacteria.

Abstract

Anaerobes are a diverse groups of microorganisms which do not require oxygen or energy for respiration/metabolism and are one of the important components of nitrogen cycle. They are capable of using various other organic and even inorganic materials as electron acceptors during respiration. Anaerobic based wastewater treatment is a biological approach where microorganisms degrade organic contaminants (i.e. rich in carbon and nitrogen) in the absence of oxygen. In this chapter, the role of anaerobes in wastewater treatment has been discussed as it offers an alternative, cheap and eco friendly treatment technology among different biological treatment methods. Anaerobic biological treatment of wastewater is well developed, understood, and frequently used in anaerobic digesters to treat complex organic carbon and nitrogen compounds such as primary and secondary wastewater sludge. The anaerobic sludge contains diverse groups of anaerobic microorganisms that work together in association via a multistage processe consisting of the following biochemical reactions like hydrolysis, acidification, acetogenesis, and methanogenesis thereby converting the organic matter to biogas. The composition of biogas includes 70% methane (CH₄) and 30% carbon dioxide (CO₂) in addition to traces of other gases (e.g., H₂ and H₂S). The methane produced as a by-product can be used as an energy source. The potentiality of anaerobes in anaerobic based bioreactors for its maximum efficiency can be implemented in a variety of ways. The chapter discusses about the working principle, performance, treatment potential, and cost implication in the application of anaerobic treatment technology. The main bioprocess parameters such as pH, temperature, mixing, organic loading rate (OLR), and hydraulic retention time (HRT) have also been discussed in brief. Anaerobic treatment offers several benefits over aerobic treatment, including lower energy requirements, less chemicals, low capital, operation, and maintenance costs, and less sludge production. Hence, it saves money and the environment and overall simplifies the whole process.

Abstract

Solid Waste Management (SWM) has become a significant global concern, specifically for developing countries like India because of increasing population, rapid urbanization and high rate of municipal solid waste generation. Bio-composting and anaerobic digestion are the methods majorly used for solid waste management. Present chapter comprises detailed information on methods, microbiology involved and pros and cons of these methods to provide the detail information of solid waste management processes to the readers. Variable nature of substrates are available for bio-composting process. It includes sludge from effluent treatment plant (ETP), sewage treatment plant (STP) and bio-toilets, municipal solid waste, food waste and garden waste etc. Nutritional content, carbon /nitrogen (C/N) ratio of the substrate, available space and cost of the process are the main factors that affect selection method for waste management. Anaerobic digestion is the preferred method of solid waste management in comparison to other processes of composting due to methane generation as biogas and bioconversion of organic compounds to manure.

Abstract

Rise in global energy demand has led to an increase in consumption of fossil fuels. In recent years, there has been an increasing awareness about the consequences of pollution and global warming caused by burning of fossil fuels. This has led to an increased interest in the search for sustainable energy. Transportation sector is a major consumer of world’s energy resources. n-Butanol is one of the most promising alternative bio-fuels which has various advantages over other biofuels. The microbial n-butanol is produced by anaerobic conversion of the substrate to n-butyric acid and subsequently utilized to form n-butanol. The present chapter explores the scope of bacterial butanol production as need of the hour and its use as an alternative biofuel.

Abstract

Hydrogen synthesis from bioprocesses a good approach for generation clean of fuel for world's development. Throughout the ancient and current periods, most of the developmental activities are completed by consumption of non-renewable fossil fuel energy that which has resulted in multiple environmental issues or challenges (Climate change and pollution by toxic gases or byproducts formation) at global level. Biohydrogen synthesis from anaerobic bacterial fermentation could be a good effort for sustainable energy production without any toxic byproduct formation. For production of hydrogen, lignocellulosic material can be utilized as cheap raw substrates. This would help the farmers in providing surplus benefits to farmer for their agriculture residues that normally burnt and cause the serious air pollution. Utilization of agro-waste residues can help in development of sustainable biofuels for world energy need. Burning of agrowaste residues by farmer's can be discouraged via utilization as raw carbon substrates thereby reducing air pollution.

Abstract

Grazing animals have developed symbiotic relationship with anaerobic microorganisms, which survive in their rumen and help in the oxidation of complex molecules of feed containing lignocellulosic materials into volatile fatty acids. The consortium comprises anaerobic bacteria, fungi and protozoans. The rich microbial diversity of rumen remains constant after its establishment and does not get affected by intruding contaminants along with feed or water. The rumen contains a wide range of microbes such as Fibrobacter spp., Ruminococcus spp., Clostridium spp., Prevotella spp., Eubacterium spp., Methanobacterium spp., Treponema sp. Lachnospira sp., Bacterioides s pp., fungi: Anaeromyces s pp., Neocallimastix spp., and protozoa: Enoplastron sp., Eudiplodinium spp., Ostracodinium sp. They often have a variety of enzymes, glucanases, xylanase, glucuronidase, pectinase and amylase, etc. These enzymes inhabit the microbes and even break down complex molecules into simpler forms like; glucose and volatile fatty acids. The present chapter discusses on the role of microorganisms of rumen.

Abstract

Anaerobic sulfur compound reduction processes make use of sulfur, thiosulfate, trithionate, tetrathionate, and sulfite during the reduction process. Complete reduction of these sulfur compounds leads to production of H₂S. Isolation of sulfur compound reducers requires a suitable electron donor and one of the sulfur compound as a sole electron acceptor during the reduction process carried out in anaerobic conditions. Anaerobic sulfur, thiosulfate and tetrathionate reductases identified to date are molybdopterin binding oxidoreductases that extract out electron during the reduction process. The electron transport chain during the reduction process involves cytochromes and menaquinones. Dissimilatory sulfite reductases include conventional siroheme dissimilatory sulfite reductase and the nonconventional sulfite reductases including ASR sulfite reductase, F₄₂₀ dependent sulfite reductase and the MccA sulfite reductase. Anaerobic sulfur compound reduction process are almost ubiquitous in nature and are important part of the biogeochemical cycle. They occurs in aquatic systems, are found in extreme environments such as hydrothermal vents, acid mine drainage sites and are also found in important human and animal pathogens.

Abstract

Methane is the second most important green-house gas and has a major role in global warming. Aerobic oxidation of methane is known for more than 100 years. Anaerobic methane oxidation (AOM) was recently discovered before ~25 years, first in marine sediments. The first discovered AOM was found to be mediated by anaerobic methanotrophic archaea (ANME) in association with sulphate reducing bacteria (SRB) and termed as sulphate dependent anaerobic methane oxidation (S-DAMO). Three main groups of ANME are present which perform methane oxidation by reverse methanogenesis pathway. Later on, methane oxidation by using nitrate or nitrite as the electron acceptor was discovered from a freshwater sediment. N-DAMO or nitrate/ nitrite dependent AMO can be carried out by an archaeal or a bacterial member, respectively. Members of Ca. Methylomirabilis oxyfera are bacteria, and use nitrite as the electron acceptor and methane monooxygenase to carry out methane oxidation. Whereas, members of Ca. Methanoperedens nitroreducens are archaea, and use reverse methanogenesis coupled to nitrate reduction. Metals like FeIII or Mn IV can also be used as electron acceptors for AOM, a process recently discovered (M-DAMO). In this case, one archaeal partner and one bacterial partner could be involved, although more research is going in this area. S-DAMO is the main methane oxidation process in the marine sediments and accounts for the major methane oxidation in the marine sediments. In fresh water sediments, aerobic methane oxidation and processes like N-DAMO seem to play an important role.

Abstract

Microorganisms that produce methane as their metabolic end product are known as methanogens. Methanogens are prokaryotic, unicellular, obligate anaerobes having fastidious growth requirements making them difficult to isolate and preserve. They catalyse the terminal step in anaerobic breakdown of organic substances. Even though methanogenic archaea or methanogens show very limited metabolic diversity, they are one of the most phylogenetically and ecologically diverse group of Archaea. Methanogenic community varies greatly with respect to temperature. Methanogens have been reported from permanently frozen habitats like permafrost to hyperthermophilic environments such as hydrothermal vents. However, the metabolic and phylogenetic diversity of methanogens in these habitats vary greatly. Methanogens are the biocatalysts, having the ability to provide a solution to help solve energy crisis by producing methane as storable energy carrier. Methane being a flammable gas, can act as a clean and renewable source of energy. The biogenic methane gas thus produced may serve as an efficient alternative for fossil fuels in the future.

Abstract

The anaerobic fungi are one of the early organisms in evolution which are commonly found in the digestive tract of ruminating and non-ruminating animals, (including herbivores) deep sea and earth, dumping sites, etc. In animals, these are considered the primary colonizers of the plant biomass ingested by them. Still their taxonomy was unclear for a long period of time. However, with the help molecular techniques, they are now classified under a separate phylum Neocallimastigomycota. There are 38 species known so far belonging to 11 genera. These have been identified based on both morphological data (like thallus, rhizoids, flagella per zoospore, etc.) and phylogenetic analysis. There is a need to explore the undiscovered anaerobic fungi and look for their potential in industrial applications and solutions to the present environmental problems. It can be achieved by improving techniques of sampling, isolation, maintenance and long term preservation. Animals like herbivores do not have the ability to produce enzymes for degrading the plant biomass and anaerobic fungi help them by producing a range of extracellular enzymes. This ability of anaerobic fungi are of use to humans in bioenergy (biogas production) and biomass degradation (by producing cellulases). Recent advances in metagenomics coupled with new methods of cultivation are helping immensely to know the uncultivated anaerobic fungal populations from the animal gut. The present book chapter discusses the past and present of anaerobic fungi, lacunaes and need for more work on this group of fungi, It focuses on the progress in sampling, isolation and preservation techniques, simultaneously discussing the advances in the application these fungi in biotechnology.

Abstract

Anoxygenic phototrophic bacteria (APB) are having the genetic potential of converting radiant energy into chemical energy useful for growth and metabolic activities without evolving oxygen. They are physiologically, metabolically and phylogenetically versatile group of organism spread in five distinct phyla; Proteobacteria (purple bacteria), Chlorobi (green-sulfur bacteria), Chloroflexi (green non-sulfur bacteria), Fir micutes (heliobacteria) and Acidobacteria. Different group of APB harbors distinct photosynthetic pigments, carotenoids, and a photosynthetic reaction center. These group of bacteria succeeds in a natural environment with light availability and presence of anoxic conditions as the pigment, and the molecular oxygen inhibits bacteriochlorophyll synthesis whereas few APB can grow in hypooxic as well as in aerobic conditions. Calvin-Benson-Bassham (CBB) pathway, reverse tricarboxylic acid (rTCA) cycle, and hydroxypropionate cycle are reported pathways for carbon assimilation in APB to fix carbon dioxide. Photosynthesis occurs in either intracytoplasmic membrane (ICM) or membrane bound chlorosomes and in the cytoplasm for few APB. APB have a wide range of potential applications including removal of H₂S from wastewater and gas streams, hydrogen production, degradation of xenobiotic, toxic metals and radioisotopes, work as host for the production of challenging membrane proteins, source of carotenoids and terpenoids, single cell protein, extensive applications in agriculture and production of bioactive compounds with antimicrobial, antioxidant and anticancer activity. The chapter is focused on the diversity of different types of APB, habitats, their growth requirements, photosynthetic machinery and biotechnological applications of APB.

Abstract

Microbes are key ingredients of various ecosystems and backbone of modern biotechnology and industry. In addition to their cultivation, purification and characterization, preservation of microorganisms is equally important. Different preservation methods and protocols have been developed for long term preservation of microbes. Microbial Resource Centers (MRCs) are providing active services in the field of life sciences. National Centre for Microbial Resource (NCMR) at National center for Cell Science (NCCS), Pune is one of the MRCs. Unlike aerobes little work has been done in the area of cultivation and preservation of anaerobic microbes. In the previous chapter we have discussed the technicalities and problems of anaerobic cultivation. The aim of current chapter is to provide the recent overview of preservation of anaerobic microorganisms like methanogens, sulfate and metal reducers and the obligate anaerobes of clinical and industrial importance with fermentative mode of life style.

Abstract

Based on oxygen requirement, microorganisms have been classified into different groups, like facultative anaerobes, micro-aerophilic, aerotolerant and strict/obligate anaerobes. Obligate or strict anaerobes are the key components of anoxic environments and provide valuable ecosystem services like methanogenesis, sulphate reduction, metal reduction, degradation of pollutants etc. Apart from being valuable for the ecosystem, they are causative agents of human infections. They are the key players of human-gut microbiology, and can be used in bio-toilets, solid waste management, anaerobic digestion of waste, wastewater treatment processes and generation of waste to energy etc. Only few anaerobic microorganisms are pathogenic in nature. A mechanistic understanding about physiology and metabolism of anaerobic microorganisms is imperative for their industrial applications. Cultivation of these organisms is the first and very important step for the basic and applied study of anaerobes. Unlike cultivation of aerobic microorganisms anaerobic cultivation needs special care and facilities for successful handling of anaerobes. In the current chapter, We tried to incorporate the components and technicalities of anaerobic pre-reduced media preparation, cultivation and successful isolation of strict anaerobes. In addition, we also tried to discuss the different tools used for cultivation of anaerobes.

Harvesting: “Removal of entire plant or economic parts after maturity from the field" is called harvesting. It includes the operation of cutting, picking, plucking or digging or a combination of these for removing the useful part or economic part from the plants / crops. The portion of the stem that is left in the field after harvest is called as stubble. The economic product may be grain, seed, leaf, root or entire plant.

Harvest Index: (H.I): It is the ratio of the economic yield to the total biological yield expressed as percentage.

H.I = Economic yield / Biological yield x 100

Time of Harvesting: If the crop is harvested early, the produce contains high moisture and more immature ill filled and shriveled grains. High moisture leads to pest attack and reduction in germination percentage and impairs the grain quality.

Late harvesting results in shattering of grains, germination even before harvesting during rainy season and breakage during processing.

Growth is the development of a plant as a whole or of a specific organ. Besides the genetic factors, the environmental factors grouped as climatic factors and soil factors influence plant growth. The supply of mineral nutrient elements to the plants is discussed in this chapter.

A complete analysis of plants detects large number of elements. But only certain elements are essential. An element is said to be essential if the plant cannot complete its life cycle without it, and if the malady (deficiency) that develops in plants in its absence can be remedied only by that element.

Earlier 16 elements were considered as essential for plant growth. They are carbon, hydrogen, oxygen, nitrogen phosphorus, potassium, calcium, magnesium, sulphur, iron, manganese, zinc, copper, molybdenum, boron and chlorine. Recently, sodium, cobalt, vanadium, silica, selenium, gallium, aluminium and iodine are added to the above list. One or the other of these elements (recently added) has been found to be essential for a particular species of plants.

Carbon dioxide, water and molecular oxygen are the forms in which C., H and O are assimilated by plants. Others are taken up by plants from the soil. Nutrient uptake by plants accounts for about 10 percent of total dry weight of crops, the remaining percentage being water. The chemical symbol and the ionic forms in which the essential elements are absorbed by the plants are as follows.

Irrigation

Irrigation is defined as the artificial application of water to the soil for the purpose of crop production in supplement to rainfall and ground water contribution.

Time of Irrigation

The time schedule which indicates when irrigation water is to be applied and the quantity of water to be applied at that time is called irrigation schedule. There are several approaches for scheduling irrigation:

1. Soil moisture depletion approach based on the available soil moisture in the root zone.
2. Climatological approach based on the amount of water lost by evapotranspiration.
3. Combination approach based on soil moisture depletion and climatological approaches.
4. Critical stage approach which indicates the growth stages at which moisture stress leads to yield loss. These stages are known as critical period or moisture sensitive period. In cereals and millets panicle initiation and flowering stages are moisture sensitive stages. In pulses and oilseeds, flowering and pod development stages are critical stages. In sugarcane active tillering or formative stage is critical and in cotton boll development is the critical stage.

Weeds are the plants, which grow where they are not wanted. Jethro Tull (1731) coined the word weed. Weeds can also be referred to as plants out of place.

Definition

Weeds are unwanted and undesirable plant that interfere with utilization of land and water resources and thus, adversely affect crop production and human welfare.

In organic agriculture weeds are treated as childrens of the soil.

In the world 30,000 species of weeds have been listed, of which nearly 18,000 cause serious damage to agricultural production. Eighteen weeds are considered as the most serious in the world and about twenty six species have been listed as principal weeds in crop fields of India, and are listed in annexure V

Crop Stand Establishment

Good crop establishment is one of the most important features in better crop production. The better crop establishment is in turn expressed as optimum plant population in fields.

Plant population is the number of plants per unit area in a cropped field. It indicates the size of the area available for individual plant.

Optimum Plant Population

It is the number of plants required to produce maximum output or biomass per unit area. Any increase beyond this stage results in either no increase or reduction in biomass.

Crop geometry is the pattern of distribution of plant over the ground or the shape of the area available to the individual plant, in a crop field.

Seed is a fertilized ripened ovule consisting of three main parts namely seed coat, endosperm and embryo which in due course gives rise to a new plant. Seed is the nucleus of life. Endosperm is the storage organ for food substance that nourishes the embryo during its development. Seed coat is the outer cover that protects or shields the embryo and endosperm.

Importance

Plants reproduce sexually by seeds and asexually by vegetative parts. Grains which are used for multiplication are called seeds while those used for human or animal consumption are called grains. Good stalks of planting materials are basic to profitable crop production. The seed or planting material largely determines the quality and quantity of the produce. A good seed or stalk of planting material is genetically satisfactory and true to type, fully developed and free from contamination, deformities, diseases and pests.

Tillage operations in various forms have been practiced from the very inception of growing plants. Primitive man used tools to disturb the soils for placing seeds. The word tillage is derived from the Anglo-Saxon words tilian and teolian, meaning to plough and prepare soil for seed to sow, to cultivate and to raise crops. Jethro Tull, who is considered as father of tillage suggested that thorough ploughing is necessary so as to make the soil into fine particles.

For better understanding of different systems of farming it is essential to study certain terminologies.

Farm is a piece of land with specific boundaries, where crop and livestock enterprises are taken up under a common management.

Farming is the process of harnessing solar energy in the form of economic plant and animal products or it is the business of cultivating land, raising livestock etc.

System refers to an orderly set of interdependent and interacting components none of which can be modified without causing a related change elsewhere in the system.

There are three district systems of farming as wetland system of farming, garden land (irrigated dry land) system of farming and dryland system of farming.

Wetland: Pertaining to soils flooded or copiously irrigated through lake or pond or tank for a least several weeks in each year (or) to crop growth in such soils. The water is not entirely under the control of the farmer.