eChapters

Isolation of Protoplasts

Protoplast is the living material of the cell however an isolated protoplast is the cell from which the  cell wall is removed. In plant breeding programme many desirable combination of characters could not be transmitted through the conventional method of genetic manipulation. Higher plants that could lead to the genetic process involving fusion between the subsequent developments of a product to a hybrid plant is known as somatic hybridization. Plant protoplasts can be isolated from cells by two methods:

Experiment - 1

Aim: Isolation of plant genomic DNA through modified CTAB method

Principle: Genomic DNA is extracted from plant material requires cell lysis, inactivation of cellular nucleases and separation of the desired genomic DNA from cellular debris. Ideal lysis method is rigorous enough to disrupt the complex starting material (plant tissue), yet gentle enough to preserve the target nucleic acid. The cetyltrimethylammonium bromide (CTAB) procedure is sufficient for the extraction and purification of DNA from plants and plant derived food stuff.  This is particularly suitable for the elimination of polysaccharides and polyphenolic compounds otherwise affecting the DNA purity and hence quality.

Experiment- 1

Aim: Direct DNA delivery to Plant by Particle Bombardment
 
In direct gene transfer method, the foreign gene of interest is delivered into the host plant cell without the help of vector. Klein and Coworkers (1987) evolved a procedure through which the delivery of DNA into cells of intact plant organs or cultured cells is done by a process called Projectile Bombardment. The microprojection (Small and high density particles) are accelerated to high velocity by particle gun apperatus. These particles with very high kinetic energy penetrate the cells and membranes and transmit foreign desired DNA inside of the bombardment cells.

Experiment - 1 
Aim: Mobilization of recombinant Ti plasmid (with gene of interest) from  
(E. coli) to an Agrobacterium tumefaciens strain. 

Principle: Due to ease of cloning and harvesting plasmids, E. coli is most popular for maintenance of plant transformation vectors. Consequently, the plant transformation vector with cloned gene of interest is mobilized to recipient Agrobacterium strain harbouring vir plasmid. Plasmid are closed, circular DNA molecules that are able for autonomous replication with a host cell. 

Experiment - 1
 
Aim: Molecular analysis of putative transformed plants by Polymerase Chain Reaction

The expression of transgenes are not identified at that time but it can be achieved through DNA analysis of that plant. The presence of transgene are generally identified of PCR-based detection followed by gel electrophoresis and comparison with standard samples. The main achievement of PCR-based detection is that it is very sensitive. The Polymerase Chain Reaction (PCR) provides a rapid and sensitive method to amplify a specific gene sequence. 

Blotting is the procedure through which nucleic acids or proteins are immobilized onto a solid support generally nylon or nitrocellulose membranes. Blotting of nucleic acid is the central technique for labeling and hybridization on membranes have formed the basis for a range of experimental techniques involving understanding of gene expression, organization, etc. More recently the identification of abnormal genes in genomic DNA has become increasingly important in clinical research and genetic counseling. We can identify inherited disease, infectious agent present in the sample by using blotting technique. It is also used to mapping restriction sites in single copy gene.

Electrophoresis is a method used to separate charged particles from one another based on differences in their migration speed. In the course of electrophoresis, two electrodes (typically made of an inert metal, e.g. platinum) are immersed in two separate buffer chambers. Gel electrophoresis is a technique used to separate molecules based on physical characteristics such as size, shape, or isoelectric point. A gel is composed of agarose or polyacrylamide. Agarose is used for separating DNA fragments in size range of 100bp to 20kb. Polyacrylamide is preferred for smaller DNA fragments. Separation is achieved by moving the negatively charged nucleic acid molecules through agarose matrix with an electric field. Rate of migration of DNA molecules is inversely proportional to their molecular weight. Smaller molecules move faster than larger ones. But conformation of the DNA molecule is also an important factor. Conformations of a DNA plasmid that has not been cut with a restriction enzyme will move with different speeds such as: supercoiled plasmid DNA will move fastest followed by linearised DNA, while open circular DNA will move at the slowest pace. To visualise DNA, gels are stained with ethidium bromide which intercalates in DNA and fluorescse under UV.

1. Microscope

The microscope is a precious instrument. There are many small objects or details of objects which cannot be seen by the unaided human eye.
 
A microscope (from Greek: mikrós, means “small” and skopeîn, means “to look”) is an instrument used to see objects that are too small for the naked eye.  In another word microscope is an optical instrument that uses a lens or a combination of lenses to produce magnified images of small objects, especially of objects too small to be seen by the unaided eye.

Tissue culture consists of growing plants cells as relatively on organized masses of cells on an agar medium (callus culture) or as a suspension of free cells and small cell masses in a liquid medium (suspension culture). In other words, In plant cell culture, plant tissues and organs are developed in vitro on artificial media, under aseptic and controlled environment. The procedure depends mainly on the concept of totipotentiality of plant cells (Haberlandt, 1902) which refers to the ability of a single cell to express the full genome by cell division.

Newer technologies involve fermentation by specific strains of lactic acid bacteria which bring specific fermentation under controlled conditions to a specific fermented product with enhanced organoleptic, nutritional and therapeutic qualities. Today health is of primary concern. It is important to have nutritionally balanced food with good bacteria. For this, probiotic foods top the list. The functional food concept was initially developed in Japan in 1990‘s as there were many side effects of allopathic medicines. A regulatory system has been initiated by the ministry of health and welfare to approve certain foods to improve health. These are now recognized as Foods for specialized health use (FOSHU). According to American dietic association (ADA) these foods are potential healthful food or food ingredients that may provide health benefits beyond the traditional nutrients. Probiotics are beneficial microorganisms. Probiotic foods as yogurt and sauerkraut are very well known. Fermentation increases the nutrient content and taste with the shelf life.

There are potential beneficial medicinal uses of probiotics for which research is limited and only preliminary results are available. Recent research on the molecular biology and genomics of Lactobacillus has focused on the interaction with the immune system, anti-cancer potential, and potential as a biotherapeutic agent in case of antibiotic-associated diarrhoea, traveller‘s diarrhoea, pediatric diarrhoea, inflammatory bowel diseases and irritable bowel syndrome (Ljungh et al., 2009). Studies of some probiotics tested in vitro on human epithelial cell lines have shown that they could block the adhesion of shiga toxin producing E. coli (Sherman et al., 2005). These are claimed to be health promoting and/ or disease preventing beyond the basic function of supplying nutrients. Probiotic foods are emerging as an important category of food supplements. Earlier workers have shown the inhibition of diarrhea caused by E.coli using probiotic lactic acid bacteria and yeast (Yan and Polk, 2006). Ratledge et al. (2002) have studied the biochemistry and molecular biology of lipid accumulation in oleaginous microorganisms.

LAB constitutes a group of gram positive bacteria. They are nonsporulating, nonrespiring but aerotolerant cocci or rods, which produce lactic acid as one of the main fermentation products of carbohydrates, they do not have cytochromes. They belong to the phylum Firmicuttes, class Bacilli and order Lactobacillaceae. The group includes several genera such as Lactobacillus, Lactococcus, Bifidobacterium, Pediococcus, Enterobacter, Corynebacterium, Streptococcus, Leuconostoc etc.

4a. Intestinal Disorders
 
History of health claims
 
According to Bottazzi (1983) it was in 76 BC that the Roman historian Plinius recommended the use of fermented milk for treating gastroenteritis. Metchnikoff claimed that the intake of fermented milk containing Lactobacilli reduces the toxin producing bacteria, thereby increasing the longetivity of the host (Metchnikoff, 1908). Tissier (1905) showed that there was an increase in the Bifidobacteria in breast fed-infants, thus claiming that the administration of Bifidobacteria to infants suffering from diarrhea was very beneficial as they supersede the putrefactive bacteria that causes the disease. Intestinal beneficial microfloras are responsible to resist the disease (Bohnhoff et al., 1954).

The lack of mechanistic understanding of probiotic activity is a major drawback for the prediction of safety of probiotic intervention. The complex gut-associated microbial ecosystem and nutritionally related factors are the most important environmental triggers for the development and modification of chronic degenerative diseases including immune and metabolic pathologies. In fact, the interaction between the gut microbial ecosystem and the host is considered to be a critical factor in overall health or disease. Whether probiotics will exert protective, harmful, immune-stimulating or immune-suppressing effects on a host is dependent on the interaction between the microbial signals, the genetic make-up of the host and the effects by the environment. Many studies have revealed that certain probiotic bacteria stimulate immune cell proliferation and activity as evidenced by the production of cytokines and antibodies, thereby enhancing the effectiveness of the immune response against pathogens. Ng et al. (2009)

Probiotic Fermented food products
 
An individual requires adequate nutrients like proteins, carbohydrates, vitamins, and minerals to maintain diet. There has been an explosion of the consumer interest in the role of enhancing the health by some specific foods or physiologically active food components, so called functional foods (Hasler, 1998). The concept of functional foods evolved in the year 1990 in Japan.

Antibiotic Resistance and Gene transfer
 
It is important that probiotic strains should be assessed for their phenotypical antibiotic resistance and potential to transfer resistance gene as otherwise they cannot be used in food (BgVV, 2000; Vankerckhoven et al., 2008). It is vital to do research on characterization of acquired resistance mechanisms and transferability of resistance genes and on methods for determining transferability.

Probiotics are measured in colony forming units (cfu). CFUs are generally measured in the millions or billions per serving. Probiotics are most commonly beneficial bacteria, but can also be friendly fungal or other organisms, that are typically freeze dried to stabilize them in an inert state during storage and production. Then their continued stability and viability, as measured by CFU counts when cultured, is dependent on limiting their exposure to stimulating environmental conditions such as temperature and moisture. Besides refrigeration, this protection can be done by packaging in glass or by adding freshness packets that helps to absorb and reduce moisture in the package.

What new research is needed, what trials and how will the ultimate consumer and Industry benefit?
 
In Brazil, the sales of functional foods amounts to US $ 500 million per year representing about 1% of the total sale of the Brazilian food processing industry. According to a report the interests are mainly for dairy products, nutraceuticals and soy-based products. ABIA forecasts a substantial growth of 4.5-5% for this segment of the market (Stanton et al., 2001). In order to exert the health benefits beyond inherent basic nutrition, it is necessary that the activity of the probiotic culture should be maintained at very high levels during the shelf life of the product.

In spite of the problems with dosage and viability of probiotic strains, a lot more work is required for industry standardization and safety issues. However, it is noted that probiotics have considerable potential against many pathogenic and other diseases. A wide range of clinical trials are still needed to standardize and optimize the conditions. Ongoing basic research will continue to identify and characterize existing strains of probiotics, identifying strain-specific outcomes, determine optimal doses needed for certain results and assess their stability through processing and digestion.

Today it has been understood that yeasts have great potentials as novel probiotics (Nayak, 2011). They have been found to be safe for human consumption in traditional fermented foods (Jakobsen and Narvhus 1996). Yeasts have a great physiological importance inside the gastrointestinal (GI) tract (Czerucka et al., 2007; Gatesoupe, 2007). Jespersen (2003) has mentioned the role of consuming fermented foods and the health benefits attributed with it.Yeasts are known for prevention of table olive (Arroyo lopez et al., 2012). Bonatsau et al. (2015) have shown multi-functional property of yeast as starters.

The shift from vegetative to reproductive phase in plants is the result of multiple gene cascades in response to photoperiodic and temperature dependent pathways, gibberellic acid pathway, vernalization pathway and autonomous pathway. The environmental cues are initially detected in the leaves and the mRNA of the flowering signal integrator FT gene, moving to the shoot apical meristem, acts as a long-distance signal for floral meristem identity. At SAM, FT-FD protein complex, based on signals from above said pathways in association with the signals from age-dependent and miRNA pathways, leads to the activation of master regulator gene of flowering AP1. The activation of genes involved in ABCDE model of floral organ differentiation, based on the directions of various cadastral genes lead to the development of floral organs. Thus, the sequential action of floral meristem identity genes, floral organ developmental genes, floral meristem size and organ number genes, floral organ pattern genes and cadastral genes leads to the flower development. This chapter sums up the gene interactions happening in leaf and SAM, leading to the development of a complete flower.

Endophytic Microorganisms

Endophytes (‘endo’, inside; ‘phyte’, plant) include microorganisms that thrive inside the plant tissues without any obvious adverse effects on the host, and they include mainly bacteria and fungi (Hallmann et al., 1997; Bacon et al., 2002; Hardoim, 2015). Endophytic microorganisms share an intimate association with the host adding essential and functional capabilities. Therefore, plant may be considered as a superorganism composed of an amalgam of both selected symbiont microbiota and host cells (Hardoim, 2015) with the new concept of holobiome, i.e., plant together with the associated microorganisms collectively governing the plant activities (Hardoim et al., 2015; Vandenkoornhuys et al., 2015).

The scientific community working in the field of crop protection is experiencing an increasing academic and industrial interest in the discovery and development of new bio-insecticides as environmentally friendly pest control tools to be integrated, in combination or rotation, with chemicals in pest management programmes. In this context, Entomopathogenic nematodes (EPNs) as a bio-control agent have proven successful and are now commercially mass produced in six of the seven continents to treat pest problem in agriculture, horticulture and forest crops. They actively search for the host, including those in cryptic habitat stages of insect pests in soil environment. They can be considered as good candidates for integrated pest management in ustainable agriculture due to plants and mammals which are not adversely affected and have ease of mass production. We present a general overview on the current state of knowledge of EPN and their mutualistically associated bacteria and their utilization as biological control agent against insect pests in world and India are briefly presented in this chapter.

“Standards are to Industry as Culture is to Society” said Shri C. Rajagopalachari, the first Governor General of India. Shri C. Rajagopalachari was inaugurating a conference on Standardization and Quality Control in February 1948. The great statesman has beautifully summed up the importance of standardization.

The basic principles on which procedures and practices are based had their origin in the United Kingdom, where the first national standardization movement started as early as 1901. Thereafter, procedures have been continuously developed, modified and improved till considerable similarity is achieved.

Every research in agriculture aims at developing a promising new technology or refines an age old technology that can help addressing the improvement in crop yield. This is a worldwide scenario to meet up with the food needs of the growing population and reducing agricultural land resources. Many traditions in the world are associated with vast knowledge of cultivating the food crops, vegetables, fruits etc using selected methods that are modified based on the needs, climatic conditions and the resources available in the place of settlements. Soil based agriculture is the most popular method of growing plants since soil is considered as the main source of nutrients and water required for the healthy growth of crops. Generally it includes 3 major steps, ploughing, sowing and harvesting.

Labour is one of the biggest input costs for vegetable growers. Vegetable farming is labor intensive and time consuming. Frequently, it is associated with low yield and poor quality production. The constraints are high labor requirements for land clearing, ploughing, bed forming, mulch laying, seeding, transplanting, harvesting and transporting. Mechanization is interjection of improved tools, implements, machines and other equipments between man and materials (soil, water, environment, seed, fertilizer, pesticides, growth regulators, irrigation water, agricultural produce and by-products such as fruits, vegetables, and seeds, etc.)

The vegetables and fruits are largely consumed fresh and day by day, their market demand is increasing due to nutritious quality. However, market supply is not sufficient to meet public demand throughout the year as production is inadequate because crop production has not increased substantially in recent years due to climatic changes. Another important reason for low production is the economic losses incurred due to damages of insect pests and plant diseases.

Since ancient times, reduction in pest and disease incidence is sought by spraying of pesticides including conventional preparations such as tobacco decoction, Bordeaux mixture, neem leaf extract etc. During the green revolution years, the synthetic pesticides were greatly recommended for pest and disease control and thereby increasing crop yields many-fold. Having experienced the spectacular improvement in both yield and quality of marketable produce, farmers were solely dependent on synthetics and ultimately abandoned other control measures.

Pesticides are an undeniable part of modern life, used to protect everything from flower gardens to agricultural crops from specific pests. Pesticides have contributed significantly to improving quality of life and safeguarding the environment. Some 20 to 40 percent of the world’s potential crop production is already lost annually because of the effects of weeds, pests and diseases (according to the FAO reports) (www.CropLifeAmerica.mht). In addition to increasing crop yields, crop protection products used in stored products can also prolong the viable life of products, prevent huge post-harvest losses from pests and diseases and protect food safety for eating.

Soybean, a source of 40 per cent good quality protein, 20 per cent oil and other nutrients has great potential in meeting nutritional requirements and extending health benefits through soy based food products to Indian population. Soy foods are nutritious, economical and good for health. Regular food use of about 10 per cent processed soybean flour with cereal flours or 25-30 g properly processed soybean per day in a diet entitles the consumer to derive maximum nutritional and health benefits at a relatively low-price. Soy food products like fullfatsoyflour, soy-based bakery products and dairy analogs (soy milk, soy paneer (tofu), curd (dahi), soyshrikhand, soy amrakhand), being the products of acceptable type to Indian population, have good scope. Different organizations have given input in R&D work on soybean processing. SPU Centre at ICAR-CIAE, Bhopal has been involved in development of number of soybased food products, technology and equipment for preparation of those. To make available the properly processed soy food products to our population, the centre is actively engaged in capacity building of upcoming entrepreneurs and entreprise development for soybean processing for food uses. Around 500 cottage scale soy food enterprises have been established in different states of the country.

Centuries before Greece and Rome were discovered, sailing ships carried Indian spices, perfumes and textiles to Mesopotamia, Arabia and Egypt. It was the lure of these that brought many seafarers to the shores of India. Emperors, kings, senators and the aristocracy transformed spices into the mostly highly prized commodities of ancient trade routes The story of Indian Spices is more than 7000 years old. By the 1400s, when navigational equipment had improved to the point that long-haul sailing became possible, European rulers set out to change the balance of world trade by funding spice-hunting missions of their own. Christopher Columbus who, in searching for a quick route to India, reached the Americas. Vasco de Gama was the first to surround Africa, and with a crew led by Ferdinand Magellan, fully circumnavigated the globe.

Spices play important roles in daily life and India is a rich repository of spices. Various biotechnological approaches like micropropagation, somaclonal variation, in vitro conservation, synseed technology, protoplast fusion, production of flavor and coloring components, and development of novel transgenics have great significance in conservation, utilization and increasing the production and productivity of spices. Protocols for micropropagation and production of disease free planting materials are available for many spices. Efficient plant regeneration protocols are also available for exploiting somaclonal variation ,where the available natural variability is relatively low. Technologies for isolation and culture of protoplasts were reported in a few spices. Development of transgenics for disease resistance is gaining momentum. Synseed and Micro-rhizome technology are also available for many spices for safe propagation, conservation, movement, and exchange of germplasm. In vitro and cryo preservation technologies for conservation of spices germplasm are available for many spices.

Mango (Mangifera indica L.) is one of the most important tropical fruits of the world and is commonly known as the ‘King of fruits’ for its high quality fruits which are very popular among the Indians (Sharma et al., 2008). It is the oldest and extensively cultivated fruit crop in India having high socio-economic significance. India is the home of more than 1000 mango varieties, which originated in the Indo-Burma region (Mukherjee, 1958). India is the largest producer of mango, grown in about 2.3 million hectares with an annual production of 15.02 million tones. However, its productivity is only 6.5 tones per ha against 30 tones per ha in Israel (Bijay Jumar, 2010). Improvement of productivity in mango continues to be the foremost issue in mango production (Sauco, 1993). Of late, all the mango importing countries are considering the India as a source of quality mangoes due to its varietal wealth and availability. Hence, it is imperative to improve the productivity and quality of Indian mangoes to meet the global need (Balamohan et al., 2014).

The word Cymbidium has been derived from a Greek word ‘Kumbos’ meaning ‘hole or cavity’ referring to the structure of the base of the lip. The genus consists of 44 known evergreen species in the family Orchidaceae, subfamily Vandoideae, tribe Cymbidieae and sub-tribe Cryptopodiinae. It is distributed from northwestern India to China, Japan, south through the Malay Archipelago to the north and east Australia. (DuPuy and Cribb, 1988). Cymbidiums have been for over hundred years one of the most famous orchids in commerce.

The orchids are commercially important group of flowering plants and their flowers are affluent in uniqueness in their shape, size and colour, exquisitely attractive, remain fresh condition for long period of time in comparison to other flowers. Orchidaceae is the second largest family among floriculture; about 25000 to 35000 species of orchids have been reported over the world (Rampal and Nagrare, 2006). India accounts for nearly 7 per cent of world’s orchids genetic diversity contributed 1300 species under 184 genera (Arora, 1983; Rampal and Nagrare, 2006) and 1150 species belonging to 164 genera (Satish Kumar, 1994) of which about 800 species are found in the North Eastern region of the country (Nagaraju et al., 2006) and many more are discovered year after year because of the prevailing congenial climatic conditions, diverse terrain and altitudinal variations, which provide suitable habitat for orchids.

Methylene-cyclo-propyl-glycine (MCPG), is a cyclopropyl derivative, grouped into the amino acids that have been isolated from the higher plants (Fowden, 1960). MCPG was identified to be closely related to two other cyclopropyl derivatives (Fig. 1), 1-aminocyclopropane – 1 – carboxylic acid from Vacciniumvitis-idaea and perry pears (Vahatalo and Viertanen, 1957; Burroughs, 1957) and â- methylenecyclopropyl alanine (MCPA or Hypoglycin A) from Blighia sapida (Hassall and Rayle, 1955; Anderson et al., 1958; Ellington, Hassall and Plimmer, 1958).

Mango (Mangifera indica L), the king of fruits, is cultivated throughout a wide range of frost-free climates (Litz 1998). It is commercially the most important fruit crop of India, accounting for more than 54% of the total mango production worldwide. The fruit of mango (Mangifera indica L.) is exceptional for its juicy, succulent, thick fruit pulp and nutrient abundance in terms of wide range of amino acids, sugars, organic acids, minerals including Ca, P, Fe, and K and vitamins. Out of several diseases which attack mango crop, mango malformation disease is a serious threat to its cultivation since it causes gross deformation of the vegetative and floral tissues (Ploetz et al., 2002; Kumar et al., 2011). Floral malformation is a major problem in mango, rendering mango cultivation unproductive in northern India and other regions of the world (Pandey et al., 1977; Ram, 1991).

Tomato (Solanum lycopersicum L.) is one of the most important vegetable crops cultivated in the world. It is used as raw in salads and also used as cooked vegetable in the preparation of curries. Processed items such as tomato puree, ketchup, pickle, chutney, whole peeled tomatoes and tomato powder are also consumed considerably. It is a rich source of Vitamins A & C. Lycopene and other flavonoids in tomato serve as good source of antioxidants. Tomato occupies 5 million hectares with a productivity of 34t/ha. in the world. In India it is cultivated in an area of 0.88 million hectares with productivity of 21 t/ha.

Soil fertility -importance

From edaphological point of view soil is a medium for plant growth. It holds and nourishes the plants. Soil fertility refers to the ability of soil to supply plant nutrients. Soil fertility and fertilizers are very much closely related terms; and cannot be neglected one from the other in their function. Soil fertility acts as a ‘SINK’ where in plants can draw nutrients for maximum productivity, where as fertilizer, acts as a ‘SOURCE’ wherein we can apply continuously different nutrients. The importance of soil fertility and nutrient management is being increasingly recognized in all countries recently to meet the demand for food and other agricultural raw materials. Intensive use of fertilizer, intensive cropping and high yielding seeds have no doubt increased the food production and reduced the food shortage but it has also ushered in innumerable problems of soil fertility, soil and water pollution. On the other hand, fast depletion of nutrients due to over exploitation, a wide spread deficiency of N, P, K and S coupled with micronutrients deficiencies specially Zn, B and Mo is taking place. Further deforestation, shifting cultivation, burning of crop residues, trees, bushes, grasses and cow dung, soil erosion, nutrient losses and imbalanced nutrient application, leaching losses etc., have aggravated the depletion of soil fertility status. The productivity of Indian agriculture solely depends on scientific management of soil fertility along with judicious and efficient use of fertilizers integrated with organic sources.

Terminology

    ·    Nutrient: Nutrients are substances required by an organism for their normal     growth and reproduction. 
    ·    Plant Nutrient: The plant nutrient is a “food” which is composed of certain chemical elements often referred to as ‘plant nutrient’ or plant food elements considered very essential for growth and development of plants. 
    ·    Nutrition: The supply and absorption of chemical compounds needed for growth and metabolism of an organism.

The following graph is a visual representation of how plant growth and/or yield is affected by nutrient concentrations

N-Transformation and availability in soils     
    a.    N-Cycle 
    b.    N transformation in  soils 
Phosphorus transformation & availability in soils: 
    a.    P-Cycle 
    b.    P transformation in soils 
K-transformations& availability in soils: 
    a.    K-Cycle 
    b.    K-Transformations

Organic matter and its composition 
Decomposition  
Types microorganisms involved 
Enzymes involved in decomposition process?

    1.    Acid soil
    2.    Causes of soil acidity   
    3.    Problem of soil acidity 
    4.    Management or Amelioration of soil acidity 
        a.    Lime requirement (LR): 
        b.    Liming reaction in soils      
        c.    Benefits of liming on acidic soils 
    5.    Calcareous soil  
    6.    Formation, characteristics & management of calcareous soil 

    1.    Salt affected soils;
    2.    Classification of salt affected soils; 
    3.    Formation of salt affected soils; 

Alkali soil
 
Alkali soils are those that contain measurable amounts of soluble salts mostly as carbonates and bicarbonates of sodium. 

Definitions of IPNM 
Concept of IPNM 
Main objectives of INM 
Components of IPNM

The objective of nutrient use is to increase the overall performance of cropping systems by providing economically optimum nourishment to the crop while minimizing nutrient losses from the field and supporting agricultural system sustainability through contributions to soil fertility or other soil quality components. NUE addresses some but not all aspects of that performance. The most valuable NUE improvements are those contributing most to overall cropping system performance. Therefore, management practices that improve NUE without reducing productivity or the potential for future productivity increases are likely to be most valuable. An excellent review of NUE measurements and calculations was written by Dobermann (2007). Table  is a summary of common NUE terms, as defined by Dobermann, along with their applications and limitations. The primary question addressed by each term and the most typical use of the term are also listed below.

Fertilizers are applied to supplement nutrient requirement of the crop. It should not be looked as a substitute to organic sources. After determination of nutrient requirement of a crop fora given yield and contribution of nutrients from different sources, articularly, from the soil source, it is necessary to supplement the balance from the inorganic sources. These are determined by field experimentation supplemented by pot-culture, laboratory and green housestudies, if necessary. When a fertilizer is applied all of its nutrient (s) are not absorbed by the crop. The interactions between soil-crop-season and other factors are quite significant. Only a fraction of the nutrient(s) is utilized by the crop.

Methods of soil fertility evaluation          
    I.    Nutrient deficiency symptoms on plants  
    II.    Plant analysis
    III.    Biological tests   
    IV.    Soil testing
    V.    Spectral sensing for site specific evaluation

Soil fertility evaluation is conducted for providing an adequate supply of essential plant nutriens to ensure optimum plant productivity, while maximising economic benefits and minimising environmental degradation.
 
Mathematical modelling of nutrient application

The significance of an essential plant nutrient was contained in the Liebig’s law of minimum.