eChapters

Raj Bahadur
    
3.1.    Nitrogen Fixation in Saline Soil
    
3.2.    Legumes and Nitrogen Fixation
    
    3.2.1.    Legumes in Saline Agriculture; Nitrogen Fixation Capabilities
    3.2.2.    Legumes in Saline Agriculture; Salinity Tolerance of Legumes
    3.2.3.    Improvement of Salinity Tolerance of Legumes
    3.2.4.    Legumes of the HALOPH Database
    
3.3.    Perspective for Saline Agriculture
    
3.4.    Impacts of Agriculture and Global Climate Change Terrestrial Biogeochemical Cycle of Nitrogen
    
    3.4.1.    Nitrogen Chemistry and Terrestrial Life
    
3.5.    Nitrogen Fixation
    
    3.5.1.    Decomposition
    3.5.2.    Nitrification
    3.5.3.    Denitrification
    3.5.4.    Bio-geochemical Linkage of Nitrogen and Carbon
    3.5.5.    Soil Organic Matter
    3.5.6.    Perturbations and N and C Biogeochemistry
    3.5.7.    Organic Nitrogen
    3.5.8.    Mineralization
    
3.6.    Factors Influencing Biological Nitrogen Fixation in Legumes
    
    3.6.1.    Temperature
    3.6.2.    Soil Water Status
    3.6.3.    Nitrogen Concentration in the Root Zone
    3.6.4.    Carbon Demand for Fixation
    3.6.5.    Seasonal Regulation of Legume Biological Nitrogen Fixation
    
3.7.    Quantification of Biological Nitrogen Fixation
    
    3.7.1.    Estimation with Empirical Models
    3.7.2.    Potential N Fixation Rate
    3.7.3.    Impact of Soil Temperature
    3.7.4.    Impact of Soil Water Status
    3.7.5.    Effect of Soil Mineral N or Internal Substrate N
    3.7.6.    Influence of Plant Substrate C or C supply
    3.7.7.    Changes in N Fixation with Plant Growth Stage
        
    References

1. Introduction

There is intense commercial interest in dehydrated fruit and vegetable products especially mango powder, banana powder, orange powder, papaya cereal flakes to powder, tomato juice powder and other vegetable powders, which are in great demand for soups, biscuit type cookies supplemented with fruit powders (Ana Maria et al. 2009; Sunita and Chauhan 2008), pizza mixes and sauces. Natural fruit and vegetable powders are gaining lot of popularity in recent years as they are very easy to handle after production, require minimum storage space and they are attractive. Tamarind powder is developed from tamarind fruit (Tamarindus indica) (Manjunath et al. 1991) and recently cashew apple and guava residues from fruit juice industry were successfully converted into fruit powders and used at different levels of wheat flour substitution for cookies formulation (Ana Maria et al.2009) and fruit puree like papaya can be mixed with cereal flour to prepare slurry and after gelatinization, the slurry can be useful for preparing drum dried flakes and powder (Sunita and Chauhan 2008). Tropical fruits are exotic in flavor but their juices and purees are seldom available in dehydrated powder (James, 1971). Citrus juice concentrates were produced during world war II in powdered form by using spray, drum, vacuum-puff, and freeze drying (USDA, 1962). The preservation of fruits and vegetables by dehydration offers a unique method, which may be considered as an alternative low cost preservation technique. A shift from fresh to more and more processed foods with significant value addition is bound to occur sooner or later considering the socio-economic changes taking place in the country and the rapid integration of Indian economy with global system. Most popular brands are found in the “ready to consume” food sector.

A. Bhattacharya

6.1.    Macronutrients (Primary)
    
6.2.    Macronutrients (Secondary and Tertiary)
    
6.3.    Micronutrients
    
6.4.    Inter-relationships Between Nutrient Elements
    
    6.4.1.    Synergism
    6.4.2.    Antagonism
    
6.5.    Potassium Inter-relationships with Macronutrients
    
    6.5.1.    Potassium Inter-relationships with Secondary Nutrients
    6.5.2.    Potassium Inter-relationships with Micronutrients
    
6.6.    Nutrient Deficiency
    
6.7.    Role of Mineral Nutrition Against Environmental Stress
    
6.8.    Role of Mineral Nutrition Against Drought Stress
    
6.9.    Role of Potassium in Abiotic Stress Resistance
    
    6.9.1.    Potassium and Drought Stress
    6.9.2.    Cell Elongation and Cell Membrane Stability
    6.9.3.    Aquaporins and Water Uptake
    6.9.4.    Osmotic Adjustment
    6.9.5.    Stomatal Regulation
    6.9.6.    Detoxification of Reactive Oxygen Species
    6.9.7.    Potassium and Salt Stress
    6.9.8.    Potassium and Low-Temperature Stress
    6.9.9.    Potassium and Waterlogging Stress
    
6.10.    Partition of Photosynthates under Nutrient Deficiency
        
References

14.1. INTRODUCTION

Barley (Hordeum vulgare L. emend. Bowden) is one the most important ancient crops and played very important role in the development of agriculture and human civilization. It has also played crucial role in the progress of science of agriculture, physiology, genetics, plant breeding and malting and brewing science. It is the fourth most cereal crop after rice, wheat and maize in acreages and production in the world.  It is grown and used all around the world in many countries and has fed livestock, poultry and people since ancient time.  Barley was domesticated about 10,000 years ago in the Fertile Crescent of the Near East. Fertile Crescent is considered the first of at least seven primary centres of agriculture origin in the world (Smith, 1998; Baik and Ulrich, 2008). Barley is best known around the world as a feed grain and a premier grains for malting and brewing. When most people think of composition of beer, they only think of barley over other cereals. Although utilization of barley for food is relatively low as compared to other cereals today, throughout its history barley has remained an important and major food source poor people living in Western and Eastern Asia and Northern and Eastern Himalayan region nation like Tibet, Nepal and in Northern and Eastern Africa (Newman and Newman, 2006, 2008). Moreover, there has been resurgence of interest and use of barley as food primarily in the developed world due to an increasing emphasis on incorporating the diversity in consumption of whole grain in people’s diets due to its health benefits.

1. White alkali soils also know as

a. Acid soil                  b. Saline soil

c. Saline sodic soil    d. Sodic soil

7.1 INTRODUCTION

An understanding of the processes of oxidation and reduction in soils and the associated changes and practical implications requires a knowledge firstly of soil respiration and the movement of O₂ and CO₂ in soils, and secondly an appreciation of the significance of the changes which occur when, as a result of the use of all the O₂ in a given zone of the soil, respiration changes from aerobic to anaerobic. This results in marked changes in the biochemistry of the system. A basic knowledge is therefore needed of the microbiology and biochemistry of aerobic and anaerobic respiration and of the physics of gas movement, as well as of the chemistry of the system.

1. Introduction

Kiwifruit (Actinidia deliciosa Chev.) is among the most recently domesticated of all fruit plants. The kiwifruit of international commerce are large – fruited selections of Actinidia deliciosa Planch and Actinidia deliciosa (A. Chev.) C F Liang et A. R. Ferguson, belongs to family Acitinidiaceae. A. chinensis has been cultivated commercially for little more than 20 years, however, A. deliciosa for about 70 years. This is known as “China’s miracle fruit” and “Horticulture wonder of New Zealand”. Although this fruit vine originated in China, yet its full economic potential was exploited by the New Zealanders, which accounts for over 70 per cent of world trade (Franco, 1990). Kiwifruit has completely replaced the older name of ‘Chinese gooseberry’. In China, ‘Mihoutao’ (monkey peach) is used for all Actinidia species, but as A. chinensis and A. deliciosa are by far the most important economically of the various Actinidia species in China, they are often simply referred to together as Mithoutao. More explicitly, the two species are sometimes referred to together as Zhonghua (Chinese) Mihoutao. In other countries of the world, its cultivation gained momentum after 1960s and now is cultivated on a commercial scale in USA, Italy China, Japan, France, Germany and Australia.

In India, it was first introduced in 1960 at Lalbagh garden, Bangalore, but the plant did not come into bearing due to lack of chilling requirement during winter for its bud break. Later on, in 1963, it was introduced in Shimla hills, where the plant came into bearing in 1969. In order to assess the performance of kiwifruit cultivation in different agro-climatic conditions of state its plantation were done at different locations. After evaluation, this fruit was recommended for commercial cultivation in mid and low hills of the state. It can also be grown in mid hill of Jammu and Kashmir, Uttrakhand, Sikkim, Arunachal Pradesh, Meghalaya, Nagaland and Nilgiri hills of south India.

Interaction of radiant energy, exhibiting the properties of both waves and particles, with matter is dealt in spectroscopy. Matter may be defined as material, existing in solid or liquid or gaseous phase, which is composed of molecules, atoms, or ions. Atoms, molecules, and ions, irrespective of their physical state, remain in constant motion in a matter. Molecules may rotate, vibrate, and move from place to place in space. While radiant energy interacts with matter, these molecular motions are influenced to some extent. It is observed that radiations from ultraviolet and visible range of electromagnetic spectrum lead to the movement of bonding electrons from lowest energy state (ground state) to higher energy state (excited state) in the molecules, while absorption of IR radiation causes the molecule to vibrate more. Such changes, referred to as transition, are responsible for changing the molecular energy level.

LUMBAR VERTEBRAE

Ox: The lumbar vertebrae are characterized by elongated flattened transverse processes (projecting outwards) and large, strongly curved articular processes (Fig.5.1a). The body is constricted in the middle and expanded at the extremities. The anterior extermity is less convex and posterior is less concave. The posterior vertebral notches are much deeper. The intervertebral foramina are often double in the anterior part of the series and are very large further back.

Myristica fragrans Houtt., the nutmeg tree is unique among spice plants as the donor of two distinct spices; nutmeg and mace.Native of Indonesia (Moluccas islands), nutmeg tree grows there abundantly and is now naturalised in West Indies, Srilanka, India, Phillipines, Tropical America and Pacific Islands. (Varghese, 2000). In India, the plant is grown in certain pockets of Kerala, Tamil Nadu, Karnataka, Goa, Maharashtra, North East India and Andamans (Krishnamoorthy, 2000). It is also grown in a small scale in Srilanka, Trinidad, China, Tobago, Zanzibar and Mauritius.

4.1. INTRODUCTION

Water stress is the single most severe limitation to the productivity of rice in the rainfed ecosystem (Widawsky and O’Toole, 1990). Drought has been defined as the inadequacy of water availability, including precipitation and soil moisture storage capacity, in quantity and distribution during the life cycle of the crop to restrict expression of its full genetic yield potential. Drought is actually a meteorological event which implies the absence of rainfall for a period of time, long enough to cause moisture-depletion in soil and water deficit with a decrease of water potential in plant tissues. Under drought conditions, water stress develops in the plants as the demand exceeds supply of water; this may occur either/or both due to atmospheric or soil conditions, and is reflected in a gradient of water potentials developed between the soil or soil-root interface and leaf, the transpiring organ. Moisture stress is likely to develop to a different rate in different plant organs along with the gradient. Drought like many other environmental stresses has adverse effects on plant growth and yield.

The products of the plants which are used as food adjuncts to add taste only is called

A. Spices                   B. Medicinal plants

C. Aromatic plants     D. Condiments

Morphology based nematode taxonomy and biodiversity studies have historically challenged most biologists. In the past few decades, there have been efforts to integrate molecular methods and digital 3D image-capturing technology in nematode taxonomy, the former to enhance the accuracy of identification of such a taxonomically challenging group and the latter to communicate morphological data. While the employment of these two methods is growing in recent taxonomic, biodiversity and biogeographic studies, a movement to abandon traditional phenotypic identification methods altogether has emerged (Eyualem Abebe et al?, 2011). Proponents try to justify this trend by citing the challenging gap between the high estimated number of undescribed species and the limited ability of traditional taxonomy to accomplish the task of documenting such diversity.

Introduction

The Heliantheae are the third-largest tribe in the sunflower family (Asteraceae). With some 190 genera and nearly 2500 recognized species, only the tribes Senecioneae and Astereae are larger. The name is derived from the genus Helianthus, which is Greek for sunflower.

This is one of the large and predominantly flourishing flowering botanical groups occurring in almost all parts of the world. Except for three species in South America, all other Helianthus species are native to North America and Central America i.e., Southwest United States-Mexico area (Heiser, 1976). The common name, “sunflower”, typically refers to the popular annual species Helianthus annuus, or the common sunflower, whose round flower heads in combination with the ligules look like the sun. This and other species, notably Jerusalem artichoke (H. tuberosus), are cultivated in temperate regions and some tropical regions as food crops for humans, cattle, and poultry, and as ornamental plants.

The species H. annuus typically grows during the summer, post summer rainy season and later in post-rainy season too with the peak growth during pre-summer season with temperatures ranging from 28^oC to 35^oC in India.

Domestication of sunflower started around 4,000 years ago in Eastern North America by the native tribes of American continent (Blackman et al., 2011). The current annual oilseed yielding sunflower was cultivated originally by local inhabitant tribes (Weiss, 2000), who used the seed as a source of food. The adaptations in annual sunflower to human cultivation include a dramatic increase in apical dominance, an increase in seed size, the loss of natural seed dispersal and seed dormancy, and the loss of self-incompatibility (Wills and Burke, 2007).

Hybridization is a potent technique to create variability for selection and breaking yield barriers, evolve varieties having built in high potential. The selection of suitable parents for hybridization is one of the most important step in hybridization program. Selection of parents on the basis of phenotypic performance alone is not a sound procedure since phenotypically superior lines may yield poor recombinations in the segregating generations. It is therefore essential that parents are chosen on the basis of their genetic value. Some of the commonly utilized techniques for assessing the genetic value of a genotype are:

16.1 Introduction
According to Howard (2001) the major world crop palms are coconut palm (Cocos nucifera L), African oil palm (Elaeis guineensis Jacq.) and date palms (Phoenix dactylifera L). Many other palm species provide products for international commerce and also grown as ornamentals. Some palm species are of local or regional importance and have great potential for expanded development and distribution. In general, commercial production of palms regularly starts on or near natural habitats with little agricultural development.

Chemical ecology is the study of ecological interactions between organisms mediated by chemical produced by those organisms. In short it is considered as the ecological functions of the chemicals. An insect, in various stages of its life history, performs various activities like host plant location, host plant selection,  feeding and oviposition, mating, escape from its natural enemies etc. and the chemicals play a crucial role than visual and audio signals. Chemical ecology encompasses the studies of these chemicals based interactions.

4.1. Introduction

Globally, rice is cultivated on about 165 million ha of land, which provides around 787 million tons of paddy annually (FAO, 2023). In Asia, 708 million tons of paddy is produced from nearly 143 million rice-cultivated areas. Rice crop is grown in a wide range of climates, varied soil types, and hydrological situations. Rice is the lone cereal crop that grows well in floods.

The rice habitat can be divided into four groups based on the hydrology of the rice field: irrigated lowland rice (79~80 million ha), rainfed lowland rice (54~55 million ha), upland rice (14~15 million ha), and flood-prone rice (11~12 million ha) (Table 4.1) (Bouman et al., 2006).

The purpose of a sub-surface drainage system is to lower the ground water table and removal of salts beyond the crop root zone. The ground water beyond table may rise due to commonly practiced flood irrigation method, seepage from unlined channels, percolation of rain and runoff water and sub-surface flow from higher areas. Sub-surface drainage consists of drains laid at a specified depth, spacing and grade below the ground surface. The size, spacing and depth of drains depend largely on the soil-water properties viz., infiltration, saturated hydraulic conductivity, drainable porosity; and the requirement of removal of water through drains in certain time period fixed on the basis of rainfall and crop cultivated. The drains are usually placed in a pervious stratum. Suitable filter of coarse sand and gravel may be used when it is placed in a low permeable stratum. Sub-surface drainage serves the important job of removal of concentrated salt solution from the crop root zone particularly in arid and semiarid region.

Advantage of sub-surface drainage system

1. Since sub-surface drainage are underground, no loss of land for cultivation. Some part of the land goes out of use for making drains in surface drainage.