eChapters

Introduction

Irrigated agriculture is dependent on an adequate water supply of usable quality. The water quality used for irrigation is essential for the yield of crops, maintenance of soil productivity, and protection of the environment as well. The quality of irrigation water is defined with respect to its effect on plant growth, soil properties, soil biological equilibrium, and irrigation technology. Conceptually, water quality refers to the characteristics of a water supply that will influence its suitability for a specific use, i.e. how well the quality meets the needs of the user. Specific uses have different quality needs and one water supply is considered more acceptable (of better quality) if it produces better results or causes fewer problems than an alternative water supply. For example, good quality river water which can be used successfully for irrigation may be unacceptable for municipal use without treatment to remove its sediment load. Similarly, snowmelt water of excellent quality for municipal use may be too corrosive for industrial use without treatment to reduce its corrosion potential.

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.

Technical Term            Definition

Infiltration                    Infiltration is movement of water from the surface into the soil or ground.

OBSERVATION

The examination of the IRS - 1A imagery under raw and the digitally enhanced modes vividly display heavy concentration of suspended sediments in certain sectors along the east coast of Tamil Nadu. Such pockets of suspended sediments are seen as long and linear bodies trending parallel to the coast to the strike length of 20 - 30 km and width of 5 - 10 km. Such Phenomenon of suspended sediments concentration are strikingly observed in two sectors. One in between Tuticorin harbour and Vaippar river mouth and the other just at the mouth of Ponnaiyar river along Cuddalore-Pondicherry coast. Both of them are observed along conspicuous (Fig.1& 2) concave coasts.

Introduction

Agriculture has historically been the primary source of income in India. It has the potential to alleviate poverty, increase income, and enhances food security for 80% of both the world’s poor and people who reside in rural areas primarily work in agriculture. One of the most effective strategies to eradicate extreme poverty, increase shared prosperity, and feed an estimated 9.7 billion people by 2050 is agricultural development. Compared to other modes, the agro - based sector’s progress is two to four times more successful in enhancing the earnings of the poorest people (www.worldbank.org).

Nearly 5 billion hectares, or 38% of the world’s land surface, is used for agriculture. Around one of this is devoted for farming, and the remaining two thirds are pastures and meadows for grazing animals. Over 10% of cropland is assigned to permanent crops like cocoa plantations, oil palm plantations, and fruit tree orchards. Yet another 21% of land is primed for irrigation, a crucial agricultural land management technique.

Introduction

Urbanization, a vital global phenomenon, refers to the process of city establishment and growth; the term commonly connotes population increase in the city from internal growth and immigration as well as their spatial expansion (Revi, 2007). Recent developments, uncontrolled population growth have been linked with the process of urbanization. Urban areas cover 3% of the global land but it gives shelter to nearly 26% of the global population (U.S. De, 2009). Increase in population growth and industrialization is posing threat to natural resources such as land air and water. Anthropogenic factors have led to change in land use pattern, high energy consumption, high level of generation of waste etc. As per UN survey, by 2050, approximately 70 percent of the global population will be living in cities (UN, World Urbanization Prospects, 2014). Unplanned growth is damaging the existing ecosystems along with that causing climate change and loss of biodiversity.

The geographical area of the union territory of Andaman and Nicobar Islands is 8, 24,900 ha with 86.9 % of it under reserve and protected forests. The humid tropical climate that prevails in the Andaman and Nicobar islands provides a unique opportunity to grow various crops. Owing to a number of factors, hardly 4.8% of the area is under cultivation. Maximizing the productivity and farm income mainly depends on effective management of natural resources like rain, soil, land as well as labour present in the Island ecosystem.  On an average, the Islands receive 3074 mm of rainfall distributed over 8 months. The rainfall is intense from June to September and may have even up to 30 rainy days per month sometimes, however, from January to April, the rainfall is scanty or absent, particularly in March. The undulating terrain results in severe water crisis during the period which is aggravated by higher evapotranspiration. The Islands receive south-west monsoon from May to September and north-east monsoon during October to January. The topography of A&N Island is undulating with a stiff terrain exposed to soil erosion due to heavy rainfall.  The crop growing season can be divided in to two major seasons viz., wet 
and dry seasons.

Polyhydroxyalkanoates (PHAs) are diverse biopolyesters synthesized by many bacteria as carbon and energy reserved materials under unbalanced growth conditions. Sand-dunes have low nutrient contents especially nitrogen (N) and phosphorus (P) thus could harbor potential PHA accumulating bacteria. There is no report of isolation of PHA producing bacteria from the sand-dunes environment.  Sand samples of rhizosphere and non-rhizosphere regions of the coastal sand-dunes were processed on Nutrient Agar and TYG-Agar media for isolation of heterotrophic bacteria.

Viruses are smaller than bacteria and require living cell for their growth. They can be detected through the bacteria to which they parasitise. Viruses are associated with both eukaryotes as well as prokaryotes and contain either DNA or RNA; only few have both DNA and RNA.

Viruses that infect bacteria are called bacteriophage. They consist of head or capsid and a tail. The head may be round, oval, polyhedral and is made up of proteins while tail is hollow and provides an exit for nucleic acid to enter in bacterial cell. The tail also helps in attachment to the cell wall surface of bacteria. After injection of the nucleic acid into bacteria they multiply and form large number of bacteriophage particles which cause lysis of the bacterial cell wall releasing many bacteriophages. Phages that cause lysis are known as lytic phages and that do not cause lysis are called temperate phage. The most common lytic phage is E.coli – a coliphage.

4.1 From Soil

Soil contains varied group of microorganisms such as fungi, bacteria, actinomycetes, algae and protozoa. The type of nutrients available, moisture, temperature and pH of the soil determine the nature of microbial population in soil. Different laboratory techniques for isolation of microorganisms have been detailed in chapter-III. These are used in particular for the isolation of specific type of microorganisms. All the techniques adopted are just to segregate the pathogens/ microorganisms from the mixture of microbial population present in nature.

(a) Isolation of Fungi

Soil contains large number of fungi and constitutes a major place of microbial population. They can be isolated in pure form by following the methods given below:

Under natural habitats microorganisms usually grow in mixed populations containing several species. This is really a problem for microbiologists because a single type of microorganism can not be studied adequately in a mixed culture. In laboratories these populations can be separated into pure cultures. The pure cultures contain only one type of organism and are thus suitable for studying the cultural, morphological and biochemical characters of an individual species. In the present days there are several ways of developing pure cultures in laboratories. Some of which are as follows:

Introduction

The concept of food security having relevance at global, national, regional, state, household and individual level is well understood as a core issue over the last three decades in the world. The World Food Conference of 1974, organized in the wake of the world food crisis of 1972-74, was largely concerned with global food security. It was felt as the common responsibility of all nations that international approaches were needed to achieve the goal of improved world food security. The food security at national level means arrangements for providing physical supply of a minimum level of food during all periods including those having harvest failures. FAO (1983) had formulated that the basic concept of food security implied that all people at all times have physical and economic access to the basic food they need. The World Bank (1986) has modified this formulation to indicate that food security is access by all people at all times to enough food for an active healthy life.

In this direction, the conference on Environment and Development held in Rio (1992), the Joint FAO/WHO Conference on Nutrition held in Rome (1992), the World Conference on Human Rights held in Vienna (1993), the International Conference on Population and Development held in Cairo (1994), the World Summit on Social Development held in Copenhagen (1995), the Fourth World Conference on Women held in Beijing (1995), the Habitat II Conference held at Istanbul (1996), the World Food Summit held in Rome (1996), etc. deliberated on various facets of food security like food security and sustainable development, right for nutritionally fit and safe food, population growth and food production, global measures to satisfy the food needs, campaign against hunger, women in food production, rural-urban linkages and so on.

Pulse production in NE states in still too low as compared to whole India. However, there is very good potentialfor enhancing pulse producity in the region and contribute to food grain production of the country. In view of these constraints, prospects for increasing pulse production from this region have been visualized.

Pulse production scenario

Despite immense importance of pulses in humanand animal nutrition, the share of north-easternregion inthe total pulse areofIndiaistoolow (0.76%)andthisregion contributesonly176.44 thousandtons(0.99%) in the all Indiapulse production (Table 1). WithinNE Region, mostof the pulsearea isoccupied by Assam and 47% of total N.E. Region’s pulse production is contributed by this state alone. After Assam, Nagaland and Tripura are major pulse growing states with 33.5 and 14.5 thousand hectares of area and 36.46and 24.20thousandtons ofproduction, respectively. In Meghalaya, pulseswere grownon4 thousandhaarea and4.2 thousand tonnesof pulses wereharvested in 2010-11. Thefactthat theaverage pulse productivity of NE region (883.0kg/ha)is much higher thanthatof whole India (689kg/ha) offers opportunityfor increasingarea and production of pulses in the region.

Introduction

Definition of ‘urban’ areas varies from country to country. Consequently, it is difficult to provide a universally acceptable meaning of the term. The difficulty has been summarised by UN (1998) as follows: “because of national differences in the characteristics that distinguish urban from rural areas, the distinction between urban and rural population is not amenable to a single definition that would be applicable to all countries” (UN, 1998). In many cases the divide between a rural and an urban area is based on the minimum population, but the number varies widely between the countries, e.g., 200 in Iceland, 2000 in some countries of West Asia, 5000 in India, and 10000 in Italy! Despite this challenge, most towns and cities are historical phenomena and have their defined administrative boundaries for services and other purposes, including municipalities. These places straight away qualify as the urban centres.

In India, the word has been defined by the Census of India (2001) as: “(a) All statutory places with a municipality, corporation, cantonment board or notified town area committee, etc.; (b) A place satisfying the following three criteria simultaneously: (i) a minimum population of 5,000; (ii) at least 75 per cent of male working population engaged in non-agricultural pursuits; and (iii) a density of population of at least 400 per sq. km (1,000 per sq. mile).” This definition was adopted for the 2011 Census.

As stated before, a careful assessment of the existing curriculum is essential before any modification is undertaken and must take into account the country’s education policy, political, economic, demographic, cultural, social and technological environment. Problems of farmers to be solved, needs to be satisfied, and priorities to be identified and addressed and then only the recommendations made for action.

Technical Knowledge (ITK) based special inputs / Techniques for plant growth

Growth of the plant has for long been believed to be due to the minerals absorbed from the soil and the food materials synthesized by the palnt. It is recognized that growth of the plant is very much regulated by certain chemical substances known as growth regulators. These substances are formed in one tissue or organ of the plant and are then transported to other sites where they produce specific effects on growth and development. These materials can be produced organically for improving plant growth.

3.1. Growth Promoting Substances

Are those organic solutions (like Panchagavya, Buttermilk & Coconut milk slurry, Amudhakaraisal) prepared using the plant and animal products, decayed fruit and other agricultural wastes. For example

Agricultural scientists and policy makers have understood that continuation of modern agriculture might lead to severe ecological and economic problems. We are also convinced that modern agriculture may not be able to meet the requirements of the ever increasing population in the future. So, we are searching for alternative technologies. Several alternatives have been proposed such as low external input agriculture, sustainable agriculture, organic farming, biodynamic farming etc. However, they require, some times little or considerable external inputs whose availability may be uncertain in future.

Hence for the developing countries, the other alternative viz., traditional methods have special advantages over modern agricultural techniques. Also the capital and technological skill requirements in the use of traditional technologies are generally low and their adoption often requires little restructure of the traditional societies. The traditional technologies are nothing but indigenous technical knowledge. By adopting such indigenous knowledge, our ancestors did not face any problem of large-scale pest out break or economic crisis unlike the today’s farmers.

Jaggery making is a simple process comprising crushing of sugarcane for juice extraction, filtration and boiling of juice for concentration and then cooling and solidifying to give jiggery blocks.

Pulses are important crops in the State of Jammu and Kashmir as they are the only source of protein, an essential part of the vegetative diet. Besides that, pulses enrich the soil fertility by fixing atmospheric nitrogen in the root nodules and improve the soil structure (Thakur et al., 2009). The tap root system explores the deeper soil strata and heavy leaf litter increases the soil organic matter. Pulses in J& K state are ideal crops for mixed and inter-cropping as well as vegetable and fodder crops. It has been estimated that by 2020 the pulse requirement for Jammu region of J&K alone will be 1.51 lakh tonnes (based on average per capita consumption of 68 grams for the projected population of 60.75 lakh) whereas the estimated requirement of J&K state as a whole works out to be 3.85 lakh tonnes (Digest of Statistics 2008-09).