eChapters

Climate refers to the long-term pattern of temperature, rainfall, humidity, wind and other weather parameters within a geographical region. Human activities such as industrialization, urbanization, deforestation, land-use change and intensive agriculture have accelerated climate change by increasing greenhouse-gas emissions. Rising temperatures, irregular monsoon rainfall, droughts, floods, cyclones and elevated atmospheric carbon dioxide now affect crop growth, development and productivity. Different crops and developmental stages vary in their tolerance to these stresses. Consequently, farmers are modifying cropping patterns, sowing periods and crop choices. This chapter examines the effects of changing climatic conditions on major agricultural crops and identifies suitable adaptation and mitigation measures.

Horticultural crops include fruits, vegetables, flowers, plantation crops, spices, aromatic plants and medicinal species. They contribute substantially to nutrition, farm income, employment, exports and livelihood security. However, their productivity and quality are highly sensitive to temperature, rainfall, humidity, drought, flooding, salinity and other climate-related stresses. Changing climatic conditions affect flowering, fruit setting, maturity, nutritional composition, pest incidence and postharvest quality. Annual and perennial crops respond differently depending on their location, growth stage and environmental requirements. This chapter examines the influence of major climatic factors on horticultural production and discusses adaptive practices required to maintain productivity, quality and economic sustainability under changing environmental conditions.

6.1 INTRODUCTION

Presently, pressure on productive land is greater than ever before and will be further more in years ahead. Per capita arable land is projected to decline from about 0.23 ha in 2000 to about 0.15 ha by 2050 (Lal, 1991). The global demand for food is projected to increase by 1.5 to 2 times due to ever increasing population and also due to demand for richer diets. On the other hand, volatility in the cost of agricultural inputs and the income generated from farm products leads to instability in the farm economy. Moreover, in conventional system, agriculture is practised for uniform application of fertilizer, herbicide, insecticides, fungicides, and irrigation, without considering spatial variability. In some cases, there is excessive use of nitrogenous fertilizer and pesticides, owing to air and water pollution but there are certain cases, where farmers hardly use any chemicals. Hence, to alleviate the ill effects of over and under usage of inputs, the scenario calls for the introduction of modern technologies to improve crop yield, provide information to enable better in-field management decisions, reduce chemical and fertilizer costs through efficient application, permit more accurate farm records, increase profit margin and reduce pollution.

Precision agriculture is a production system that promotes variable management practices within a field, according to site conditions. This system is based on new tools and sources of information provided by modern technologies. These include the global positioning system (GPS), geographic information systems (GIS), yield monitoring devices, soil, plant and pest sensors, remote sensing, and variable-rate technologies for applicators of inputs. Precision farming is concerned with the management of variability in the dimensions of both space and time. Aspects of precision farming, therefore, encompass a broad array of topics, including variability of soil resource base, weather, plant types, crop diversity, machinery performance and most of the physical, chemical and biological inputs used in production of a crop. These are closely linked to the socio-economic aspects of production system. Success in precision framing is directly related to how well it can be applied to manage the space-time continuum in production system. Thus precision farming is technology enabled, information based, and decision focused. It is the integration of these technologies that has enabled farmers and their service providers to do things not previously possible, at level of detail never before obtainable, and, when done correctly, at level of quality never achieved before. In our country, vast data on various aspects like soil characteristics, climatic parameters, topographic features, crop requirement in terms of consumptive use and nutritional requirements have been generated and instruments needed for recording these parameters are also available. However, applications of precision farming as a package in the farmer’s field have received little attention, although some aspects of precision farming have been prasticed. This has been primarily due to lack of awareness about the potential for increasing productivity and improving the quality of produce with minimum use of inputs.

Introduction

Agricultural research and development in the past 50 years has primarily focused on increasing productivity through intensification of input use to  maximize grower income and  minimize hunger and food shortage (Andow et al., 2009). The full environmental costs of this policy such as water and soil pollution, soil and resources impoverishment (Tegtmeier & Duffy, 2004), only recently became apparent, and this awareness has led to the beginning of a change in philosophy away from purely production-oriented practices towards those that are more environmentally sustainable (Alexanian, Metera, & Schuler, 2009). In addition, agriculture and its interactions with the natural environment have begun to emerge more strongly in political, economic and social agendas reflecting the increasing importance of sustainability to consumers. Consumers are now demanding food that are of high quality, locally produced, regionally specialized, organic, fairly traded, and are humanly and ethically produced. Achieving all or some of these goals with fewer resources is now the objective of modern sustainable agriculture (Mason, 2003).

Azolla, a fresh water fem is a rich source of nitrogen especially for low land rice farming. It is found in rice paddies in many tropical countries like China, India, Korea, Philippines and Vietnam. The agronomic importance of Azolla lies in its ability to fix atmospheric nitrogen through the symbiotic association with a blue-green alga, Anabaena azolae. The symbiotic association can fix nitrogen proportional to its biomass produced. When Azolla is grown in paddy f ields and subsequently incorporated as green manure, the nitrogen contained within Azolla biomass is mineralized during the process of decomposition.

Azolla is a genus of small aquatic fern comprising 7 living and 25 fossil species, which is globally distributed. It occurs on still water ponds, lakes, swamps, lagoons and paddy fields in both tropical and temperate regions. Because of its rapid growth, high nitrogen percent and its ability to grow in stagnated waters, it has been used as organic manure in Vietnam and China for centuries. Its use in India and other countries is relatively recent. Azollla pinnata is native to India and widely distributed.

Introduction

Conventional agriculture is highly dependent on fossil fuel based mineral fertilizers to compensate for removal of plant nutrients by crops. Chemical fertilizers are not only in short supply but also are very costly. The preparation and use of organic manures are not being practiced in a scientific manner to harness the plant nutrients removed by plants, animals and humans.

The application of chemical fertilizers to soil alone and in an imbalanced way has resulted in deterioration of soil health and its quality. The use of chemical fertilizers has to be reduced to check the soil and water pollution and simultaneously the role of soil microorganisms has to be augmented by different ways such as greater use of biofertilizers. Moreover, the demand for organic food particularly both in developed and developing countries is on rise which opens up immense possibility to use organic manure and biofertilizers for production of foods grains, fruits, vegetables, spices, tea and coffee. Therefore, the production and the use of biofertilizers assumes greater significance and could be an excellent biological alternative to chemical fertilizers.

In spite of considerable progress achieved during the last four decades in vegetable production in India, average productivity of vegetable crops is still low as compared to national and world level, indicating the scope to enhance their yield potential of quality produce. This is because of an appealing gap between potential yield and actual yield. In many vegetables, yield realized is even lesser than 50 % of potential yield. Sometime, farmers growing vegetable crops during main season do not get back their cost of cultivation. The prices of the same vegetable produce is very high during off-season. Several biotic and abiotic stresses are major factors responsible for low productivity and poor quality in different vegetable crops under open field cultivation, especifically in rainy and post-rainy seasons. The increasing demand of off-season high quality vegetables in various markets of big cities has called the attention of vegetable growers for diversification from traditional techniques of vegetable cultivation to modern systems of cultivation.

Protected cultivation of vegetable crops offers best choice for diversification. Production of crops under protected conditions has great potential in augmenting production and quality of vegetables, in main and off-season, maximizing water and nutrient-use efficiency under varied agroclimatic conditions. This technology has great potential especially in peri-urban areas, since it can be profitably used for growing high- value vegetables like tomato, cheery tomato, coloured Capsicum and parthenocarpic cucumbers, and healthy and virus-free seedlings in agri-entrepreneurial models.

Orchids are perennial ornamental crop, grows well in shady and humid places in wild habitat. The same growing conditions can be achieved by making special structures known as orchidaria or orchid houses.
Basics for Orchid House Cultivation
The following points should be considered during the construction of orchid houses:-
    ·    Topography of land.
    ·    Climate of region.
    ·    Type of soil and water.
    ·    Accessibility of area, transport and marketing facilities.
    ·    Proper drainage facilities.
    ·    Availability of good quality irrigation water.
    ·    A good infrastructure like availability of electricity.

8.1 INTRODUCTION

Amaranth is one of the oldest food crops in the world, with evidence of its cultivation reaching well back to 6700 BC. The genus Amaranthus consists of nearly about 60 species, which includes leafy vegetables, vegetables for grains, ornamental plants as well as weeds. The word amaranth has actually been derived from the Greek word amarantos, which means unwithering and the people who used it symbolize immortality. The Hindi term for amaranth, Ramdana, means God’s own grain. Amaranthus tricolor L. is the most common species grown as leafy vegetable during summer and rainy season in India but it can be grown throughout the year. It fits well in crop rotations because of its very short duration and large yield of edible matter per unit area. The estimation of the extent of its cultivation is not available. Green or leafy types are usually grown in kitchen and market garden. Amaranth is more widely used as a potherb. The grain Amaranthus species are popular in the high lands of tropical and sub-tropical America. It is gaining importance in the Indian plains also, particularly in Gujarat and Maharashtra. Grain types are usually grown as mixed crops along with cereals, pulses and vegetables.

The leaves and tender stems of Amaranthus are rich in protein, minerals, vitamin A and vitamin C. A 100g of edible portion of Amaranthus consists of Protein 4.0 g, Calcium 397 mg, Iron 25.5 mg, Magnesium 247 mg, Phosphorus 83 mg, Potassium 341 mg, Sulphur 6 mg, Vit C 99 mg and Vit A 9200 IU. Besides, the soft fibrous matter provides necessary roughage in the diet

The fresh tender leaves and stem of Amaranthus are delicious when cooked and consumed like other leafy vegetables. The tiny seeds of grain Amaranthus are parched and milled for flour. Amaranthus flour compares favourably with other cereals in taste, nutritional value and yield. The grain Amaranthus is a rich source of protein and essential amino acids like lysine, leucine and isoleucine which are required for growth of children. In spite of several advantages of amaranth as leafy vegetable, both its stems and leaves also contain the anti-nutritional factors such as nitrate and oxalate, which can be removed by cooking with ample water. In general, the presence of oxalates causes the kidney stone, while that of nitrates causes methaemoglobin in blood. Therefore, it is recommended not to consume leaves of more than 200 g/day/head.

Botanical Name: Areca catechu L. Family: Arecaceae / Palmae Chromosome No: 32 Place of Origin: Philippines, Malay, Indonesia, Cochin, China and Malaya Peninsula Common Name: Betel nut 3.1 Introduction Arecanut (Areca catechu L.), commonly known as Supari or Betel palm or Arecanut palm, is cultivated primarily for its kernel obtained from the fruit which is chewed in its tender, ripe or processed form. It is an important cash crop of India. The economic produce is the fruit called ‘betel nut’ and used mainly for masticatory purposes. Its cultivation is restricted in South Western and North Eastern regions of the country. The chromosome number of Areca catechu L. was first determined as 2n=32 (Venkatasubban, 1945) and it belongs to family Arecaceae. It is one of the important commercial crops grown in parts of Karnataka, Kerala, Assam, Meghalaya, West Bengal, and Andaman and Nicobar Islands. The cultivation of arecanut has also been extended to other states like Tamil Nadu, Andhra Pradesh and Maharashtra. India is the largest producer and consumer of arecanut in the world holding 62% of the area and 60% of the production. The other major arecanut growing countries are Indonesia, Bangladesh, China, Myanmar and Thailand. Arecanut being a profitable plantation crop, it is important to understand the package of practices and seasonal operations to be followed in the nursery, in young gardens and in old plantations to get maximum returns. To get additional income in the adverse periods, concept of cropping system is very important. The exact origin of areca nut is not known till date but, arecanut is a palm which grows in much of the tropical Pacific, Asia, and parts of East Africa (Kumar, 2013).

Importance

It helps to cope with fever, cough and cold, stress, high blood pressure, excessive fats in body. It lowers the cholesterol level, cleanse the body by eliminating toxic substances, improve the digestive system, improve blood circulation, cleanses other organs of our body including kidney, pancreas, liver, bladder etc.and aid to deal with menstrual problems. The oil is distilled from leaves and flowering tops of Lemon grass. The oil has strong lemon-like odour, due to high percentage (over 75%) of citral in the oil. The characteristic smell of oil makes its use in scenting of soaps, detergents, insect repellent preparations. However, the major use of oil is as a source of citral, which goes in perfumery, cosmetics, beverages and is a starting material for manufacture of ion ones, which produces vitamin – A. The Citral rich oil has germicidal, medicinal and flavouring properties. An allied species called West Indian lemon grass (C.citratus) has low citral content in the oil and has meager trade in the country.

17.1 INTRODUCTION

Basella is a short-lived but productive leafy vegetable of the tropics. Its resistance to pests and diseases makes it very promising for small-scale production in home and market gardens. The plant is a climbing vine with thick fleshy stem and leaves. They are chopped and cooked as vegetables and has ornamental value too. Its leaves are rich source of vitamin A (3250 IU/100g), protein (1.2%) and rich source of iron (1.4mg/100g). The succulent leaves with petioles and tender leaves are cooked as vegetables. The plant is a climbing vine with thick fleshy stem and leaves. It was cultivated since long in South-East Asia and China, and is now widespread throughout tropical Asia, Africa and America. It is a popular vegetable in Malaysia and the Philippines. The colouring matter present in the red cultivar is reported to have been used in China as a red dye for official seals, as ink. These are used to allay fever and as a mild laxative for pregnant women. A decoction from the plant is used to alleviate labour pains. Boiled leaves are used as a poultice. Flower spikes are sold as vegetable in northern Thailand markets. Flowers have been reported as an antidote to poisons. Fruit juice is used as eye-drops in the treatment of conjunctivitis. Cooked roots are used to cure diarrhoea, while cooked leaves and stems are used as a laxative. The red types of Ceylon spinach are very popular ornamentals and are grown as a pot plant in Europe.

17.1 Introduction

Basella is a short-lived but productive leafy vegetable of the tropics. Its resistance to pests and diseases makes it very promising for small-scale production in home and market gardens. The plant is a climbing vine with thick fleshy stem and leaves. They are chopped and cooked as vegetables and has ornamental value too. Its leaves are rich source of vitamin A (3250 IU/100g), protein (1.2%) and rich source of iron (1.4mg/100g). The succulent leaves with petioles and tender leaves are cooked as vegetables. The plant is a climbing vine with thick fleshy stem and leaves. It was cultivated since long in South-East Asia and China, and is now widespread throughout tropical Asia, Africa and America. It is a popular vegetable in Malaysia and the Philippines. The colouring matter present in the red cultivar is reported to have been used in China as a red dye for official seals, as ink. These are used to allay fever and as a mild laxative for pregnant women. A decoction from the plant is used to alleviate labour pains. Boiled leaves are used as a poultice. Flower spikes are sold as vegetable in northern Thailand markets. Flowers have been reported as an antidote to poisons. Fruit juice is used as eye-drops in the treatment of conjunctivitis. Cooked roots are used to cure diarrhoea, while cooked leaves and stems are used as a laxative. The red types of Ceylon spinach are very popular ornamentals and are grown as a pot plant in Europe.

4.1 INTRODUCTION

It is an annual crop cultivated all over India, Bangladesh, Pakistan, China, Japan, South East Asia and Philippines. The fruits are available practically throughout the year. Brinjal fruits are a good source of calcium, phosphorus, iron and vitamins particularly ‘B’ group. A 100 g of edible fruit contains 91.5g of water, 6.4 g of carbohydrates, 1.3g of protein, 0.3g of fat and 0.5g of mineral matters. Its green leaves are the main source of vitamin C (38-104.7mg/100g). Dark purple brinjal has more vitamin C than those with white skin. Bitterness in brinjal is due to presence of glycoalkaloid solasodine. Generally, high amount of glycoalkaloids (20mg/100g) in the fruits produce a bitter taste and off flavour. Brinjal is reported to stimulate the intrapeptic metabolism of blood cholesterol and has marked drop in blood cholesterol level. The de-cholestrolising action is attributed due to the presence of poly-unsaturated fatty acids, PUFA (linoleic and linolenic) which are present in flesh and seeds of fruit in higher amount (65.1%). The presence of Mg and K salts also helps in de-cholestrolising action. Dry fruit is reported to contain goitrogenic principles. Aqueous extracts of fruit inhibit choline esterase activity of human plasma. Brinjal has got much potential as raw material in pickle making and dehydration industries. It is supposed to contain certain medicinal properties and white brinjal is said to be good for diabetic patients. The fruits are regarded as a cure for toothache. It is also an excellent remedy for those who are suffering from liver complaints. Cu content and polyphenol oxidase activity are highest in purple colour fruits and lowest in white fruit. Fe and catalase activity are highest in green fruited cultivars and lowest in white fruited cultivars. White fruited cultivars contain twice as much crude fibre as the purple and green fruited cultivars. Solanum ferox is yellow fruited type and is very popular in southern Europe, France and Italy and USA. Vitamin C content of brinjal is affected by canning. Toasting of fruits raises the nicotinic acid at the expense of trigonellin which is present in it and 66-69% of it is converted into nicotinic acid during toasting.

Brinjal is a self-pollinated crop but cross-pollination also occurs in it i.e., it is often cross-pollinated and pollination is mainly done by bumble bees and honey bees. To encourage pollination and visit of these bees, Mimosa pudica plants should be planted in the vicinity of brinjal. Brinjal flowers are divided into four types namely (i) long styled (ii)Medium styled (iii) pseudo-short styled and (iv) short styled. The maximum fruit setting in different cultivars is in long styled flowers which ranges from 70-86.7% and in medium styled it ranges from 12.5 to 55.6%. There is no fruit setting in pseudo-short and short-styled flowers. In India it is produced in an area of 0.669 million ha with a production of 12.4 million tonnes.

4.1 Introduction

It is an annual crop cultivated all over India, Bangladesh, Pakistan, China, Japan, South East Asia and Philippines. The fruits are available practically throughout the year. Brinjal fruits are a good source of calcium, phosphorus, iron and vitamins particularly ‘B’ group. A 100 g of edible fruit contains 91.5g of water, 6.4 g of carbohydrates, 1.3g of protein, 0.3g of fat and 0.5g of mineral matters. Its green leaves are the main source of vitamin C (38-104.7mg/100g). Dark purple brinjal has more vitamin C than those with white skin. Bitterness in brinjal is due to presence of glycoalkaloid solasodine. Generally, high amount of glycoalkaloids (20mg/100g) in the fruits produce a bitter taste and off flavour. Brinjal is reported to stimulate the intrapeptic metabolism of blood cholesterol and has marked drop in blood cholesterol level. The de-cholestrolising action is attributed due to the presence of poly-unsaturated fatty acids, PUFA (linoleic and linolenic) which are present in flesh and seeds of fruit in higher amount (65.1%). The presence of Mg and K salts also helps in de-cholestrolising action. Dry fruit is reported to contain goitrogenic principles. Aqueous extracts of fruit inhibit choline esterase activity of human plasma. Brinjal has got much potential as raw material in pickle making and dehydration industries. It is supposed to contain certain medicinal properties and white brinjal is said to be good for diabetic patients. The fruits are regarded as a cure for toothache. It is also an excellent remedy for those who are suffering from liver complaints. Cu content and polyphenol oxidase activity are highest in purple colour fruits and lowest in white fruit. Fe and catalase activity are highest in green fruited cultivars and lowest in white fruited cultivars. White fruited cultivars contain twice as much crude fibre as the purple and green fruited cultivars. Solanum ferox is yellow fruited type and is very popular in southern Europe, France and Italy and USA. Vitamin C content of brinjal is affected by canning. Toasting of fruits raises the nicotinic acid at the expense of trigonellin which is present in it and 66-69% of it is converted into nicotinic acid during toasting.

1 What is the best time to sow onion seeds in Northern Hilly regions?

 a) January to February b)  March to April

 c) May to June  d) September to November

 2 Which type of soil is best for onion cultivation?

 a) Sandy loam    b)  Clay loam

 c) Alluvial soil  d) Both a and b

 3 What should be the pH range for onion cultivation?

 a) 4.4-5.0    b)  5.5-6.5

 c) 6.0-7.5    d)  6.5-7.5