eChapters

It is generally observed that N, P and Zn content in soil decreases with increasing soil salinity. Nutrient imbalances created by continuous use of chemical fertilizers, particularly nitrogenous fertilizer alone, combined with sub optimal rates of other nutrients or total omission of other nutrients are the primary causes for unsustainable yields of crops in saline soil. A sustainable approach for nutrient management in salt affected soils should therefore include balanced use of organic, inorganic and biological sources of nutrients (Bandyopadhyay and Rao, 2001). Organic amendments are known to facilitate the reclamation of sodic soils and better nutrition of crops (Anand swarup, 1992).

Experiments at Central Soil Salinity Research Institute (CSSRI), Kamal, India showed that alkali soils are not always high in available P and rice and wheat significantly responded to addition of P (Pathak et al., 1975).

The availability of phosphorus in soil either native or added is limited by fixation and precipitation mechanisms. The organic acids released during decomposition of organic matter influences the soil pH, form stable complexes with cations responsible for P fixation and thus increases the availability (Tiwari et al., 1980).

The use of bulky organic manures (Maurya and Ghosh, 1972; Chaudhary et al., 1981) and green manures (Prabhakar et al., 1972; Sharma et al., 2000) has been found very beneficial for P management of saline and alkali soils as these improve the soil physical condition and the availability of soil phosphates.

Potassium availability in most of the coastal salt affected soils of India is rich except when the soils are low in clay content (Bandyopadhyay et al., 1985). Plants grown under high salinity may show K deficiency due to the antagonistic effect of Na on K absorption and / or disturbed Na / K ratio. Under such conditions application of K is also known to reduce the adverse effect of salinity and sodicity on crop growth (Qadar, 1995). Singh et al. (1980) reported that the addition of FYM increased the K concentration in the soil. Swarup (1987) reported that the incorporation of green manure increased the available N, P and K status of the soil. Available P and K remarkably increased to a tune of 30 and 44 per cent respectively by the application of coir waste (Santhi et al., 1991).

The uptake of Mg by rice plant was highest when fertilizer was applied in combination with vermicompost (Jadhav etal, 1997). Pattanayak etal. (2001) also reported the highest Ca uptake in the treatments that received green manuring of dhaincha. Sriramachandrasekharan (2001) who reported the highest Fe uptake of rice with green manuring of Sesbania aculeata.

Debele et al. (2001) reported that the application of FYM enriched with 10% rock phosphate + gypsum with PSB and PSF @ 500 g inoculums t^-1 of FYM increased the nutrient uptake of maize. The higher nutrient uptake of 227 kg N ha^-1, 59.5 kg P ha^-1 and 227 kg K ha^-1 recorded with the application of enriched FYM @ 2 t ha^-1.

Introduction

Several hazardous chemicals, microbes, and techniques like recombinant DNA technology are used for research and development work in research Institutes and universities. Therefore, the researchers, technical, helping and supporting staffs as well as the laboratory outputs must be kept free from contaminations. Thus, biosafety is necessary to prevent unintentional exposure/ release of hazardous chemicals, microbes/pathogens, and toxins to the laboratory staff and environment. Following the biosafety guidelines and ethical considerations are essential to maintain safety standards for the researchers as well as the environment. This chapter deals with various biosafety measures and ethical issues to be strictly followed while working in a research laboratory. The required safety level needs to be determined as per the chemical/biological materials are used in the laboratory to keep the researcher/environment safe for sustainable research and developmental activities.

Biosafety

The term biosafety is used to describe the procedure and policies needed to ensure environmental and personal safety. Biosafety refers to the containment principles, technologies and practices that are implemented to prevent unintentional exposure to pathogens, toxins, or their accidental release into the environment. A fundamental objective of any biosafety program is the containment of potentially harmful chemical/biological agents as precautionary safety measures.

Why Biosafety?

With the increasing number of countries adopting molecular biology tools and techniques in life science research and development activities, especially in the areas of agriculture and medicine, the biosafety issues are gaining importance to ensure biological safety for the public and the environment. Conducting research in safe and sustainable manner is not only a personal requirement but essential collective efforts to ensure biological safety for a clean and safe environment. This requires rules, regulations, monitoring bodies, and awareness among the workers as well as the public. Therefore, biosafety per se is an integral part of laboratory research and requires awareness among the researchers so that biological safety can be well taken care from the grassroot level.

Introduction
 
Nanotoxicity is a serious concern to be addressed sooner than later as nano-based processes and products in various fields are being extensively exploited. Nanotoxicology is the science of engineered nanodevices and nanostructures that deals with their effects in living organisms (Oberdorster et al., 2005). The unique property of nanoparticles is in its very large surface area to mass ratio, which is considered to be a boon to create novel products. But this distinctive property also challenges the way we identify, understand and address potential risks caused by nanoparticles (Rajkishore et al., 2011). It is sufficient to alert us to the fact that some engineered nanoparticles do indeed behave differently to their more conventional counterparts and may present new and unusual risks. Kahru and Dubourguier (2010) assessed the existing literature on nanotoxicity to main food chain levels (bacteria, algae, crustaceans, ciliates, fish, yeasts and nematodes) and classified the NPs of Ag and ZnO as “extremely toxic”, C60 fullerenes and CuO NP as “very toxic”, SWCNTs and MWCNTs as “toxic” and TiO₂ NP as “harmful”. 

Introduction

Biosensor technology is a powerful alternative to conventional analytical techniques, harnessing the specificity and sensitivity of biological systems in small, low cost devices. Despite the promising biosensors developed in research laboratories, there are not many reports of applications in agricultural monitoring. The authors review biosensor technology and discuss the different bio-receptor systems and methods of transduction. The difference between a biosensor and a truly integrated biosensor system are defined and the main reasons for the slow technology transfer of biosensors to the market place are reported. Biosensor research and development has been directed mainly towards health care, environmental applications and the food industry. The most commercially important application is the hand-held glucose meter used by diabetics. The agricultural / veterinary testing market has seen a number of diagnostic tests but no true biosensor systems have made an impact.

Bioshields offer barriers of vegetation, shrubs, small and big trees and if integrated as a well designed system they can greatly help our coastal as well as inland areas. Though primarily looked at for coastal regions, under a broader definition Bioshields can play important role in semi-desert areas, hills, etc. also.

Why Bioshield?

Bioshields or Biobarriers can make a major contribution in minimizing the effects of storms, cyclones and Tsunamis and at the same time offer short and long term ecological and livelihood benefits.

Biostimulants examines substances and microorganisms that enhance plant physiological processes, growth, development, and tolerance to environmental stress. The chapter distinguishes non-microbial and microbial biostimulants and discusses plant extracts, protein hydrolysates, animal-derived hydrolysates, humic substances, seaweed and macroalgal extracts, and secondary metabolites. Microbial examples include nitrogen-fixing and nutrient-solubilizing organisms, arbuscular mycorrhizal fungi, Trichoderma, Bacillus, Pseudomonas, microalgae, and cyanobacteria. Their implications for germination, metabolism, root development, crop quality, growth promotion, and abiotic-stress tolerance are described. The chapter provides a framework for understanding biostimulants as complementary tools within sustainable crop production and natural farming systems. in modern sustainable crop production for farmers worldwide under diverse agricultural production conditions.

Introduction
Biotechnology represents a transformative force in modern agriculture, offering innovative solutions to enhance crop production, improve resistance to diseases, and address the global challenges of food security and climate change. Chapter 9 delves into the multifaceted role of biotechnology, particularly in the realm of genetic innovation, and how it is reshaping the agricultural landscape. The chapter begins by exploring the various applications of biotechnology in crop improvement. This includes the development of genetically modified organisms (GMOs) and transgenic crops, which have been engineered to exhibit desirable traits such as increased yield, pest resistance, and enhanced nutritional content. These advancements have significantly contributed to the global food supply, particularly in regions facing harsh climatic conditions or limited agricultural resources. A detailed examination of genomic tools and techniques follows, highlighting the sophisticated methodologies employed in biotechnology. Techniques such as CRISPR -Cas9 gene editing, marker-assisted selection, and genomic sequencing are discussed, showcasing their pivotal role in accelerating the development of improved crop varieties. These tools have enabled scientists to manipulate genetic material with unprecedented precision, paving the way for more efficient and targeted crop breeding programs. The chapter also addresses the role of biotechnology in crop protection, emphasizing its importance in developing crops that are resistant to pests, diseases, and environmental stresses. By enhancing the natural defense mechanisms of plants, biotechnology reduces the need for chemical pesticides, thereby promoting more sustainable agricultural practices and minimizing the environmental impact of farming. The importance of biotechnology and genetic engineering in ensuring food security is a central theme of this chapter. As the global population continues to grow, the demand for food is expected to increase dramatically. Biotechnology offers a viable solution to meet this demand by enabling the production of higheryielding and more resilient crops. This section also explores the ethical and regulatory considerations surrounding the use of GMOs and other biotechnological innovations in agriculture.

Stress is an intrinsic part of biological systems, and successfully adapting to stimuli that induce stress is essential for the survival of dryland crops and farm animals kept in a complex and ever-changing environment. Here the biotic stresses of crop plants are treated and not that of farm animals to avoid the expansion of the volume of the chapter. Biotic stress in plants is caused by living organisms, specifically viruses, bacteria, fungi, nematodes, insects, arachnids, and weeds. In contrast to abiotic stress caused by environmental factors such as drought and heat. Biotic stress agents directly deprive their host of its nutrients leading to reduced plant vigour and, in extreme cases, death of the host plant. In agriculture, biotic stress is a major cause of pre- and postharvest losses. Plants respond to biotic stress through a defence system (Atkinson and Urwin, 2012).

Introduction

Black cotton soils are formed by the solidification of molten magma; it covers a large area of the Deccan plateau. The depth of this soil is very high in the lower part of the Krishna – Godavari basin. The clay fraction is very high which is responsible for the heavy waterlogging in the area of heavy rainfall and become more vulnerable to soil erosion. The fine fraction of soil not allows draining out through the soil profile and at the same time the rate of evaporation is low. During summer soils suffer from moisture stress and it becomes very hard but at the same time during the rainy season moisture content very high. this imposes severe constraints on conventional agriculture use as a result most of the land remains fallow and subjected to soil erosion due to heavy rain. The nutrient status of the soil is quite good in Vertisol but these constraints limit crop production. To manage black cotton soil for crop production it is advisable to use animal-powered devices for surface soil drainage, Counter cultivation, adoption of a new cropping system will be helpful for better crop production.

Rice is grown in about 40 million hectares of land in India and nitrogen requirement for the crop is 60 lakh tonnes based on the present levels of consumption. Rice production has to be sustained and increased to provide staple diet to our increasing population. Blue green algae is a potentional biofertilizer in rice because of their capacity to meet both carbon and nitrogen requirement naturally from the air. They are microscopic algae which are collectively called phytoplankton produce basic organic matter forming the first link in food chain and alongwith replenish the oxygen content of atmosphere. Algae contain proteins, Vitamins, iodine, bromine and substances of antibiotic and stimulatory nature. The soil algae are divided into chlorophyta (green algae) cynophyta (blue green) bacillariophyta (diatoms) and xanthophyta (yellow-greens).

De (1939) suggested that fertility of rice fields is maintained due to the growth of blue-green algae. Different types of blue-green algae have been reported to colonize the rice fields. The cells such as heterocysts in Anabaena, Nostoc, Tolypothrix etc. which have capacity to fix atmospheric nitrogen under aerobic condition and unicellular and non- hetercoystous forms also fix atmospheric nitrogen under microaerophilic conditions.

Boron (B) de?ciency has been realized as the second most important micronutrient constraint in crop production after that of Zn in the world (Ahmed et al., 2012). However, in Nepal, B de?ciency is more wide-spread than Zn de?ciency, as 80 to 90% of soil samples were de?cient in B, 20 to 50% in Zn and 10 to 15% in Mo (Anderson, 2007). In India, B de?ciency has increased from 2% of the soil samples de?cient in B in 1980s (Katyal and Vlek, 1995) to 52% soil samples in 2000s (Singh, 2012). Total B content in Indian soils varies from 7 to 630 mg kg^–1 soil (Kanwar, 1976); being the highest in arid regions of the country and the lowest in wet humid regions of the country (Behera et al., 2009; Prasad et al., 2014). Boron de?ciency is most in the heavy rainfall areas of Western Ghats of Maharashtra, Karnataka and the eastern states of Bihar, Odisha, Jharkhand and Chhattisgarh states of India (Fig.13.1). The wide-spread de?ciency of B in India can be seen from the fact that B fertilization recorded the highest bene?t : cost (B : C) ratio in rice–wheat cropping system at Palampur (Himachal Pradesh), Ludhiana (Punjab), Faizabad, Modipuram and Varanasi (Uttar Pradesh), Pantnagar (Uttarakhand) and in rice–rice cropping system at Maruteru (Andhra Pradesh), Karjat (Maharashtra) and Jorhat (Asom) (Singh and Goswami, 2014). Response of wheat to B fertilization is also reported from Bangladesh (Halder et al, 2007).

Crop production is challenged by abiotic and biotic stresses results in low yield and high production costs.

Magnitude and intensity of stresses are increasing dramatically due to climate change causing recurrent droughts, increased temperature (heat) and emergence of new diseases and pests.

5.1. Characteristics of asexually propagated crops

Majority of them are perennials

Many of them show reduced flowering and seed set.

Invariably cross pollinated.

Mostly polyploids.

Many species are inter specific hybrids.

4.1. Synthetic varieties

Produced by crossing in all combinations, a number of lines that combine well with each other.

3.1. Selection

To isolate desirable plant types from a population.

3.1.1 Progeny test

Evaluation of growth of plants on the basis of performance of their progenies

Real value of plant could be known by studying the progeny.

18.1. Buffer stock

Refers to stock of food grains maintained by government to be used as a buffer to cushion shocks of fluctuating supply and price, to meet the emergency needs and to meet the situations arising out of serious unexpected shortages resulting from transport bottlenecks, natural calamities like war, flood, famine, earthquakes, and from the influx of refugees.

Introduction

Calcareous soils are those that contain high levels of calcium carbonate (CaCO3 ) that affects soil properties related to plant growth, such as soil water relations and the availability of plant nutrients (Elgabaly, 1973), and give effervescence visibly releasing CO2 gas when treated with dilute 0.1 N hydrochloric acid. The pH of calcareous soil is > 7.0 and also regarded as an alkaline (basic) soil.

Calcareous soils have often more than 15% CaCO3 in the soil that may occur in various forms (powdery, nodules, crusts etc.). Soils with high CaCO3 belong to the Calcisols and related calcic subgroups of other soils. They are relatively widespread in the drier areas of the earth. They occupy >30% of the earth’s surface, and their CaCO3 content varies from just detectable up to 95% (Marschner, 1995).

Formation of calcareous soils

Calcareous soils occur naturally in arid and semi-arid regions because of relatively little leaching. They also occur in humid and semi-humid zones if their parent material is rich in CaCO3 , such as limestone, shells or calcareous glacial tills, and the parent material is relatively young and has undergone little weathering. Some soils that develop from calcareous parent material can be calcareous throughout their profile. This will generally occur in the arid regions where precipitation is scarce. It has been estimated that these soils comprise over one-third of the world’s land surface area (Taalab et al. 2019, Aboukila et al. 2018).