eChapters

Abstract
The cultivation of grain legumes is expanding globally because of their diverse applications as food for humans, feed for livestock, and raw materials for industrial purposes. Legumes contribute significantly to sustainable agricultural practices due to their unique ability to fix atmospheric nitrogen through symbiosis with rhizobia bacteria in their root nodules. Incorporating legumes into cropping systems in place of traditional cereal-cereal rotations can significantly enhance agricultural sustainability due to their multiple benefits. Their role in nutrient cycling, particularly nitrogen and phosphorus, ensures that subsequent crops benefit from improved soil nutrient availability, making legumes an essential component of crop rotations and intercropping systems. Additionally, legumes improve soil structure, organic matter content, and decrease the environmental impact associated with excessive fertilizer use, such as greenhouse gas emissions and water pollution. With the increasing demand for plant-based foods and the economic challenges of fertilizing cereal crops, grain legumes are anticipated to play a more prominent role in cropping systems, especially in regions where fertilizer availability and affordability are limited. It includes studies on improving nitrogen fixation efficiency, enhancing phosphorus uptake, and developing varieties that are better adapted to specific environmental conditions and cropping systems. Additionally, there is a need to identify the most suitable legume species and varieties for different regions and cropping patterns to ensure maximum productivity and sustainability.
Keywords: Climate change mitigation, Grain legumes, N fixation, P availability, Soil organic carbon

9.1. Nutrient deficiency of corrective measures

9.1.1. Major and secondary nutrients

Cashew (Anacardium occidentale L.) is the principal and one of the most important horticultural products of India. In spite of its immense popularity and commercial importance, information relating to nutrient deficiency/toxicity symptoms in cashew has not progressed much. Nutrient deficiency is common in cashew growing soils as most of the cashew plantations in India are established on degraded slopes with poor fertility, where soil and water erosion are common phenomena. Nutrient deficiency in cashew is influenced both by soil and climate.

Previous Year Questions

1. Discuss the iron and protein malnutrition in India. Describe the dietary pattern for mitigating the above-said malnutrition. (15M, IFoS-2022)

2. What is protein energy malnutrition? Give micronutrient deficiency in women and children. (20M, CSE 2017)

3. How are vitamins classified? Name the blood clotting vitamin. Give its various functions and sources. (10M, 150W, CSE 2019)

4. What do you mean by nutrient deficiency? Explain the micro-nutrient deficiency in context of work capacity of women and children. (12.5M, CSE 2015)

There is a lot of confusion and lack of understanding when it comes to scheduling of fertigation. Even crop specialists prepare a fertigation dosage by dividing the total fertilizer quantity by the number of days of crop growth. This is highly erroneous. A scientifically prepared fertigation plan allows coordination of nutrient supply with changing demands of the growing crops which changes with the physiological shifts in the crop. Fertigation planner requires following information to prepare this schedule- which, when and how much plan:

Soil is a major source of nutrients needed by plants for growth. The three main nutrients are nitrogen (N), phosphorus (P) and potassium (K). Together they make up the trio known as NPK. Other important nutrients are calcium, magnesium and sulfur. Plants also need small quantities of iron, manganese, zinc, copper, nickel, chlorine, boron and molybdenum, known as trace elements because only traces are needed by the plant. The primary nutrients are nitrogen, phosphorus and potassium, because they are required in larger quantities than other nutrients. These three elements form the basis of the N-P-K label on commercial fertilizer bags. As a result, the management of these nutrients is very important. However, the primary nutrients are no more important than the other essential elements since all essential elements are required for plant growth. Remember that the ‘Law of the Minimum’ tells us that if deficient, any essential nutrient can become the controlling force in crop yield.

Introduction

Increase in population in our country with decrease in cultivable land is putting the challenges to the scientists and policy planners for increased food supply. There is very little scope for horizontal increase in cultivable land. Hence, the way to meet the need for providing food to ever increasing population is to increase the production of food per unit area of cultivable land.

Farmers, generally apply fertilizer to soil on blanket recommendation. Sometimes, the addition of nutrients is inconsistent. Sometimes, the application of fertilizer is much higher than the recommended dose. Imbalanced application of fertilizer to soil results in low nutrient use efficiency and low crop yield. There is need of site specific nutrient management for increased crop yield and for achieving higher nutrient use efficiency. Proper care should be taken for selection of fertilizer, method of application of fertilizer, rate of fertilizer application and also time of nutrient supply to the soil. Excess application of fertilizer has an adverse effect on soil health.

Traditional tillage may affect physico-chemical as well as biological properties of soil. Change in tillage practice from conventional tillage to conservation agriculture method may have an impact on soil properties and nutrient dynamics. Conservation agriculture affects soil health, proper fertilizer application, both rate and time, along with efficient use of soil moisture improves nutrient use efficiency. For obtaining a good crop yield nutrient should be available for plants in adequate quantity and in right proportion. Nutrients removed by the crop should be replenished by application of inorganic fertilizers alongwith incorporation of organic manures. Soil test is an important tool for determining the quantity of nutrients available in the soil. Based on soil test values and nutrient requirement of the crop rate of fertilizer to be applied in the soil for the plant is determined. Ample quantity of farm yard manure is not available nowadays. Hence, other organic manure such as town waste, green manure etc should be used.

Nutrient film technique popularly known as NFT is one of the methods of soilless farming or hydroponics where in plants have their roots in a shallow stream of recirculating water containing all the nutrients required for plant growth dissolved without any solid growing medium. The lower portion of roots remain submerged in flowing nutrient medium in a water tight gully having enough air for the roots. The nutrient film technique was developed during the late 1960s by Dr Allan Cooper at the Glasshouse Crop Research Institute, England. The method is already used in commercial horticulture in many countries including India. NFT is potential for other crops such as animal fodder and even energy-source plants for fuel production.

NFT related technologies

Hydroponics : Cultivation of plants in nutrient solutions is known as hydroponic cutlivation. This ia gerally done under protected structures and in containers arranged horizontally or vrtically (vertical garden). Use of nutrient film or fertilizers is made to feed the plants. Hydroponics can be practiced following nutrient film technique method, trough method, deep water floating method and coco peat bag culture.

The foods we eat contain nutrients. Nutrients are substances required by the body to perform its basic functions. Nutrients must be obtained from diet, since the human body does not synthesize them. Nutrients are used to produce energy, detect and respond to environmental surroundings, move, excrete wastes, respire (breathe), grow, and reproduce. There are six classes of nutrients required for the body to function and maintain overall health. These are carbohydrates, lipids, proteins, water, vitamins, and minerals. Foods also contain non-nutrients that may be harmful (such as cholesterol, dyes, and preservatives) or beneficial (such as antioxidants). Nutrients that are needed in large amounts are called macro-nutrients. There are three classes of macro-nutrients: carbohydrates, lipids, and proteins. These can be metabolically processed into cellular energy. Micro-nutrients are nutrients required by the body in lesser amounts, but are still essential for carrying out bodily functions. Micro-nutrients include all the essential minerals and vitamins. There are sixteen essential minerals and thirteen vitamins.

Plants require altogether 17 essential elements to nourish themselves and to complete their reproduction and life cycle. Among them nine elements are required in large amounts for their growth, the so called macro nutrients like C, H, O, N, P, K, Ca Mg and S.  The former three elements (C, H and O) are available to the plants through air and water over which we have relatively little control either in their application rates or uptake into plant system.

With the introduction of high yielding varieties and use of high analysis fertilizer in intensified agriculture under irrigation condition resulted in green revolution in our country. But continuous use of chemical fertilizer in indiscriminate manner without assessing soil also had adverse effect on productivity and environment. Though use of high analysis fertilizer ensured the high production but also resulted in acceleration of mining of native sources of nutrient. This has led to appearance of hidden hunger of several other essential nutrients and sustainability of our agriculture has become venerable.

Sustainability in agricultural production is guided by the overriding philosophy of ‘feed the soil to feed the plant’. Adequate supply of plant nutrients is required to ensure efficient crop production. Plants use individual chemical elements and ions as their food. In 1939, Arnon and Stout laid down three criteria for the essentiality of a plant nutrient.

The arid region of India covers about 12 % of countries geographical area and occupies over 3.17 lakh Km² of hot desert located in the parts of Rajasthan (61%), Gujarat (20%), Punjab and Haryana (9.0%), Andhra Pradesh (7%), Maharashtra (0.4%) and Karnataka (3.0%). In addition to this an area of about 78 thousand Km² of cold desert in Jammu & Kashmir and Himachal Pradesh presents an entirely different set of agro climatic conditions as compared to hot arid zone. The hot arid region is characterized by low and erratic distribution of rainfall (< 100 to 400 mm), high temperature, low relative humidity, high potential evapo-transpiration, high sunshine and high wind speed during summer. Soils of this region are dry for most part of the year and suffer from water stress. Besides growing annual crops, a great emphasis is being laid on the development of agroforestry systems in this region which also includes cultivation of arid fruit crops in cropping systems. Horticulture based production systems are considered to be the most ideal strategy to provide food, nutrition and income security to the people (Chundawat, 1993). Integration of annual crops with fruit trees yields multiple outputs that ensure production and income generation.

Soil

Soil is the upper most crust of earth surface which supports plant growth. It is defined as a three phase system in which plants grow. These phases are solid, liquid, and gas are essential. Solid part is frame which provides space for other two. It consists of minerals, clay minerals and organic matter. The soil is also a living system with millions of microbes that breakdown organic matter. The microbes are very essential and survive only when soil is well aerated and rich in organic matter and devoid of waterlogged conditions. Texture of soil depends on the size of solid particles and classified as gravel, coarse and fine sand, silt and clay. Soils are classified according to the relative distribution of these particles. Likewise, arrangement of these particles is referred as structure. Generally loamy soils and crumb structure are most growing preferred for fruit crops. According to level of organic matter, soils are classified as mineral soil or organic soil and soil having more than 20% organic matter is organic soil like peat and muck etc. Minerals and salts lend chemical properties to the soil like pH, alkalinity, sodicity, salinity and cation exchange capacity which influences the availability of nutrients in soil. Therefore, for making choice for soil, soil analysis in terms of following criteria isessential to decide on land capability. Maximum numbers of fruit orchards in India are depleted from micro and macro plant nutrients which interrupted the growth and development of the fruit plants and their quality. Therefore, like growers are not attain profit desired. To obtain marketable fruits, nutrients managements are highly beneficial to the fruit growers rainfed areas. Analysis of soil is useful to determine the level of the elements available in the orchards to get maximum yield.

10.1 What is nutrient management?

• Nutrient management is an important component in orchard management for high efficiency and high fruit quality. Fruit trees are perennial woody plants which can store nutrients and then release them for growth.

• Therefore, the nutrient uptake of fruit trees includes the total nutrients of the fruits, leaves, new branches, and time increments of storage. Nutrient uptake is different under different yield levels. For example, the N uptake of apple trees was 100–120, 110– 130,120–140, and 130 150kg/ha under yield levels of 30, 45, 60, and 75t/ha, respectively.

• Basal fertilization is considered to be important for high-quality fruit production by providing nutrients for tree growth and also improving soil structure which promotes better root development. It is usually recommended and immediately applied during the dormant season up to autumn, after fruit harvest.

• Top dressing applications are usually chemical fertilizers which are applied two to four times before bud break or prior to or after blooming and at the fruit enlargement stage, depending on the requirements of each type of fruit tree.

• Using this INM method, the total nutrient demand is calculated according to target fruit yield level and NPK fertilizers are recommended based on soil fertility index (High, Moderate, and Low soil fertility) and nutrient demand with different stages. For moderate apply trees, most of N fertilizer is applied in autumn after picking to add N storage and renew tree vigor, and most of the P fertilizer is applied in spring with flowing stage to improve flower bud quality, and most of the K fertilizer is applied in summer fruiting period to improve fruit quality. Management of high yielding fruits using suitable pruning, and irrigation, are combined in this INM

The fundamental idea behind integrated nutrient management, or INM, is to optimize plant nutrient supply in order to maintain the targeted crop yield. It entails using chemical fertilizers, organic manure, and biofertilizers in the right amounts according to the land use system and the environmental, social, and economic circumstances. Vermicomposting is a natural fertilizer that is devoid of chemicals and made from organic wastes that decompose. It is an environmentally benign process. Beneficial microflora, including those that fix nitrogen, dissolve phosphorus, and break down cellulose, are abundant in vermicompost. In addition to having earthworm cocoons, which boost the number and activity of earthworms in the soil, it also has important vitamins, enzymes, and hormones like auxin and gibberellins, which improve the soil’s structure, texture, aeration, and ability to hold water while preventing soil erosion. Additionally, because of its high organic matter content, it increases the soil’s capacity to retain water, improves the macro- and micronutrient quality of the soil, and encourages greater root development and nutrient absorption. Porosity, aeration, drainage, and water-holding capacity are all extremely high in vermicompost (Sinha, 2009). Profile of Nutrients in Vermicompost: C:N ratio of 15.5. N = 1.6%, P = 0.7%, K = 0.8%, Ca = 0.5%, Mg = 0.2%, Fe 175.0 ppm, Mn 96.5 ppm, Zn 24.5 ppm, Cu 5.0 ppm, T = 0.5%. Biofertilizers are substances that include living microbes that, when added to soil, colonize the plant’s interior, or rhizosphere, and increase the host plant’s availability or supply of primary nutrients, so promoting growth. Biofertilizers provide soil with nutrients by utilizing the body’s natural mechanisms of fixing nitrogen, phosphorus solubilization, and growth-promoting material production. It can symbiotically link with plant roots because it is a living entity. Complex organic material could be simply and safely converted into a simple chemical by the involved microorganisms, making it easier for plants to absorb them. Long-term microorganism function leads to an increase in soil fertility. It preserves the soil’s natural habitat. In addition to increasing plant development, it substitutes artificial nitrogen and phosphate by 25% and enhances crop output by 20% to 30%. According to Hazarika and Ansari (2007), biofertilizers have the capacity to fix 20–200 kg N/ha/year, solubilize

According to the present state of our knowledge, sixteen-elements are considered to be essential for plant growth and development. These nutrients are chemical elements, which are absorbed by the plants in more or less quantity to transform light energy into chemical energy and to keep up plant metabolism for the synthesis of organic material. These elements are regarded as essential in higher plants.

These are Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus, Potash, Calcium, Magnesium, Sulphur, Zinc, Manganese, Copper, Iron, Boron, Molybdenum and Chlorine. Carbon, Hydrogen and Oxygen are obtained from air and water. Carbon makes up the great bulk of the plant and is obtained from carbon dioxide in the air. Hydrogen is derived mainly from the breakdown of water. Oxygen is obtained from air as well as water. Other thirteen elements are obtained from mineral and organic components of the soil. These elements are further grouped into major/macro and minor/micro-elements. The nutrients that are required in relatively larger quantities are termed as macro elements. Micronutrients that are required in relatively lesser quantities are termed as micro nutrients.

Pineapple is considered as one of the important tropical fruits which are extremely demanded in the international market. This is due to its various quality characteristics like sweeter taste, blemish-free flesh, a cylinder shape with golden yellow pulp, a very pleasant aroma when ripe, low acidity, and a longer shelf life compared to other varieties (Banful et al., 2011; Malezieux et al., 2003). Pineapple can grow well in low as well as high fertile soil but the best production is obtained with high fertile soils. Souza et al. (2007) found that a fruit’s weight is directly correlated with the plant vigour at the time of f loral differentiation with a minimum D-leaf length. Therefore, it is proved by Souza et al. (2007) that nutrients play animportant role in pineapple cultivation to increase the growth and yield of the crop. It is also noted that the pineapple plants have a large nutrient uptake demand, especially for potassium, followed by nitrogen, calcium, magnesium, sulphur, and phosphorus.

The focus on pineapple production should not only aim for stable volumes but also sustainable growth while maintaining quality standards amidst a growing population. The ‘Green Revolution’ with high inputs has plateaued, emphasizing the need for a natural balance to sustain life and property. Effective plant nutrient management is crucial for environmental, economic, and social reasons. Pineapple’s nutrient requirements, high in nitrogen (N), potassium (K), and iron (Fe), with lower needs for phosphorus (P) and calcium (Ca), make soil organic matter desirable. Repeated cultivation exhausts soil nutrient reserves, leading to decreased yields. Heavy synthetic fertilizer use may cause soil impaction and acidification. Combining organic manure with chemical fertilizers is recommended for profitable and sustainable crop production while preserving soil fertility. However, excessive nitrogen application poses health risks. As farmers transition to organic farming, the negative impact of inorganic fertilizers on pineapple size, yield, and quality is evident.

Salt affected soils occupy 962.2 m ha globally which accounts for 33% of the arable land. In India 8.373 m ha is affected with salts. Of which 2.359 m ha are alkali soils, 3.829 m ha are saline soils and 2.185 m ha coastal saline soils. Reclamation of these soils provides additional area for food grains production and employment.

India is a leading vegetable producing country in the world. Presently it occupies 7.981 million hectare area with the annual production 129.077million tones (2008-09). The country being belessed with the unique gift of nature of diverse climate and distinct seasons, make it possible to grow an array of vegetables number exceeding more than hundred types. However, potato being the staple food and easy to mix in several preparations ranks first (26.6%) in total production of vetetables followed by onion (10.5%) and other important Solanaceous vegetables like tomato (8.6%), brinjal (8.0%). Cauliflower and cabbage are most preferred winter vegetables and their total share in the country’s vegetable production is 5.1 and 5.3%, respectively. Other important vegetables, which are primarily grown in the country, are okra, onion, vegetable peas and a good range of cucurbits (Fig. 1)

There is miss-match in area production and productivity of vegetables among various states of the country. The West Bengal ranks first in the total production of vegetables in the country and its production during the year 2008-09 was in tune of more than 22.704 million tones, contributing the more than one-fifth of total country’s vegetable product ion. Uttar Pradesh, Bihar and Orissa in north India and Maharashtra, Tamil Nadu and Karanataka in south India are the other leading vegetable producing states in the country. In last one decade, there has been considerable progress in enchancing the productivity of vegetables which is presently 16.2 tonnes hectare^-1. Incessant growth of urbanization, ceaseless fragmentation ofland holdings and depleting natural resources are the major challenges before the expansion of any agricultural commodity either cereals or vegetables. Hence, our attention must be focused on vertical expansion strengthened with the boon ofthe technology instead of horizontal expansion just by increasing the crop area. To ensure the nutrition security of the burgeoning population of the country, it is estimated that up to 2020, the country’s vegetable demand would be around 155 million tones (Rai et al., 2004; Pandey et al., 2009). To achieve this target, it is sine qua non to integrate the various technologies right from production to post-harvest.