eChapters

Abstract

As we have entered in the post genomic era where we have successfully completed the full genome sequencing of many important crop species and now the future challenge is to ascertain the functions of all genes present in plant genome.

Abstract

Of the various rhizosphere associated bacteria, Azospirillum species are probably the most studied and appear to have significant potential for commercial application. During the last 35 years of studies of Azospirillum–plant interaction, over 20 proposals were suggested for the mechanism of action by which Azospirillum  enhances plant growth, yield and nutrient uptake. Besides, fixing the nitrogen with associative symbiosis, they impart a number of beneficial effects on plants such as phytohormone production, siderophore production, enzyme production, proliferation of root system, enhanced water and mineral uptake, mobilization of minerals, mitigation of environmental stressors of plants, and moderate biocontrol potential. The following plant responses to Azospirillum inoculation in agriculture crops were often reported: increase the germination percentage and height of the seedlings, increase the total number and length of adventitious roots and root hairs, increase the hydraulic conductivity of the root system, increase in the height of the shoot and dry matter production and yield of the crop plants. The effect of Azospirillum inoculation on the total yield increases of field grown plants generally ranged from 10 to 30 per cent. This article reviews the recent researches on role of Azospirillum in plant growth promotion.

Introduction

It is carried out by 15 centres that are members of the CGIAR Consortium, in close collaboration with hundreds of partners, including national and regional research institutes, civil society organizations, academia, development organizations, and the private sector.

History

It was formed in response to the widespread concern in the mid-20th century that rapid increase in human populations would soon lead to widespread famine. The Rockefeller Foundation and the Mexican government, in 1943 laid the seeds for the Green Revolution when they established the Office of Special Studies, which led to establishment of the International Rice Research Institute (IRRI) in 1960 and International Maize and Wheat Improvement Centre (CIMMYT) in 1963. However, these foundations alone could not fund all the agricultural research and development efforts needed to feed the world’s population. In 1969, the Pearson Commission on International Development urged the international community to undertake “intensive international effort” to support “research specializing in food supplies and tropical agriculture”. Thus, with the support of World Bank, FAO and UNDP, CGIAR was established on May 19, 1971, to coordinate international agricultural research efforts aimed at reducing poverty and achieving food security in developing countries

Introduction
As the seed market has become more globalized, seed trade has seen a rise in competitiveness as well as stricter quality requirements. Throughout the entire seed manufacturing process, thorough management is necessary to ensure high seed quality, from initial planning to final distribution. Among the various seed quality parameters, genetic purity is particularly critical in determining the authenticity and planting value of a seed lot. Genetic purity refers to the degree of purity within a seed lot, the genetic integrity of an F1 hybrid in a hybrid seed lot, or the difference between a submitted seed sample and the stated variety. During manufacturing, achieving complete (100%) varietal purity is challenging, even when recommended protocols are strictly followed. Outcrossing, partial off-type removal, and physical mixing during harvest, storage, or seed handling are a few examples of these factors can result in unintended varietal impurities (Bradford, 2006). Seed firms, producers, and suppliers conduct laboratory-based evaluations for internal quality control or post-control grow-out testing on seed lots to guarantee the necessary levels of purity. Assessments for genetically modified trait purity and the accidental inclusion of genetically modified (GM) seeds in non- GM seed lots are now necessary due to the introduction of transgenic varieties into the worldwide market, which has further broadened the scope of seed purity testing. Thus, seed purity testing is a cornerstone of agricultural production, ensuring that the seeds sown in the fields conform to their designated genetic identity. This process is essential for maintaining varietal integrity, meeting regulatory requirements, and ensuring high agricultural productivity (Sandra et al., 2023). The quality and genetic purity of seeds all directly impact crop productivity, pest and disease resistance, and overall farm profitability. Traditional seed purity assessment methods rely heavily on morphological, physiological, and biochemical traits. These methods include visual examination of seed characteristics, seedling grow-out tests, electrophoresis-based protein profiling, and chemical marker-based identification. However, these approaches often suffer from several limitations, such as the influence of environmental conditions on phenotypic traits, subjective assessments, and the need for significant time and labour. The accuracy and reproducibility of such conventional techniques can be further affected by variations in experimental conditions and the expertise of personnel conducting the tests.The advent of molecular biology has brought a paradigm shift in seed purity testing. DNA-based technologies provide precise, reliable, and high-throughput solutions that overcome the limitations of traditional methods. These molecular approaches allow for direct examination of genetic material, offering greater accuracy in varietal identification, hybrid seed purity assessment, and detection of genetic contamination. DNA markers can distinguish even closely related varieties, enabling seed companies, regulatory bodies, and farmers to ensure the authenticity of seed lots with high confidence. This chapter provides an overview of various DNA-based techniques employed in seed purity testing, including polymerase chain reaction (PCR)-based markers, single nucleotide polymorphism (SNP) markers, and high-throughput sequencing (HTS) technologies.

Nano-bioinoculants are revolutionizing modern agriculture, empowering farmers with an innovative and environment-friendly approach to crop cultivation. This chapter delves into the fascinating world of these tiny technological breakthroughs that work seamlessly with nature to significantly enhance crop yields in a sustainable manner. Their remarkable ability to deliver essential nutrients directly to plants, fortify crops against drought and diseases, and minimize the reliance on harmful chemicals will be highlighted. By presenting real-world success stories, we will illustrate how farmers are harnessing these advancements to produce healthier food while conserving valuable resources. Nevertheless, the path to widespread adoption is not without its challenges; which will be confronted for critical issues such as costs, regulatory hurdles, and the transition of these solutions from laboratories to agricultural fields. Looking ahead, we will envision a future where nano-bioinoculants synergize with other cutting-edge farming technologies, paving the way for truly sustainable food systems that can meet the demands of our growing population.

Heavy metal contamination in soils and water is a risk to environmental health, agricultural production and human well-being. Conventional remediation methods are expensive and not particularly efficient, so nanobioinoculants are being accepted as a more sustainable solution for bioremediation of heavy metals. Combinations of nanoparticles and microorganisms work together to increase the removal or immobilization of toxic metals from contaminated environments. Nanobioinoculants provide advantage of the high surface area and reactivity of nanoparticles, alongside the metabolic diversity of microbes like bacteria, fungi, and actinomycetes. These microbes facilitate the heavy metal detoxification through the mechanisms such as biosorption, bioaccumulation, biotransformation, and nanoparticle assisted immobilization. Mostly microbial strains have metal tolerance and the ability of biofilm formation provides further protection and play a role in sequestration of the heavy metal. Nanoparticle integration with microbes increases their resilience to perform well in harsh conditions. With these advantages nanobioinoculants are found to be a sustainable and effective way of combating heavy metal contamination in the environment. The present chapter explores the synergetic action of nanotechnology and microbial inoculants, which is the role of nanobioinoculants in mitigating heavy metal pollution by sustainable

As per United States Department of Agriculture (USDA), organic farming is defined as a system which avoids or largely excludes the use of synthetic inputs (such as fertilizers, pesticides, hormones, feed additives etc.) to a maximum extent and feasible rely upon crop rotations, crop residues, animal manure, off farm organic waste, mineral grade rock additives and biological system of nutrient mobilization and plant protection. FAO suggested that organic agriculture is a unique production management system which promotes and entrance agro-ecosystem health, including biodiversity, biological cycles and soil biological activity and this is accomplished by using on-farm agronomic, biological and mechanical methods is exclusion of all synthetic off-farm inputs.

Essential elements for plant growth

A large number of mineral elements are present in plants, but they do not require all these for growth. Out of the 107 elements in the periodic table, 90 elements are naturally occurring in plants and out of which only 17 elements are essential for plant growth.

Although common sense goes a long way in defining the concept of an essential element, Arnon and Stout in 1939, stated that an essential element should fulfil following criteria:

1. A deficiency in absence of the elements should make it impossible for the plant to complete its lifecycle.
2. Must not be replaceable by another element.
3. Must be directly involved in plant metabolism, that is, it must be required for a specific physiological function.

   To Arnon and Stout’s three requirements for essential elements should be added a fourth:

Abstract

Cancer is a potent disease causing nearly 6 million deaths per year worldwide. There are a number of cancers such as skin, brain, lung, breast, stomach, colon and blood cancer caused due to number of factors like unbalancing of hormones, smoking etc. Cancer could be treated by chemotherapies or through irradiation therapies.

Wide hybridization or distant hybridization is crossing between two different species or genera, and has been used successfully to transfer genes and to create new crop species. Wild plant species related to crop plants form an important source of useful traits for quality improvement and biotic and abiotic stress tolerance. Cultivated species has lost many beneficial traits for stress tolerance in the process of domestication and selection, which resulted in uniformity in many agronomic traits. Although there have been multiple cases of valuable tolerant genes being transferred from wild rice to cultivated rice, it is now necessary to look at new breeding and selection strategies that may be applied to wide hybridization. It breaks the species barrier for gene transfer and makes it possible to transfer the genome of one species to another, which results in changes in genotype and phenotype of the progenies. The barriers in wide hybridization occurs as prezygotic and postzygotic barriers. Techniques of chromosome doubling, bridging species, protoplast fusion, and embryo rescue are highly beneficial in recovering fertile progenies by overcoming various barriers in wide crossings. Broadening the gene pool of a crop is an important plant breeding method as it can enhance tolerance of major biotic and abiotic stresses and improve the quality characteristics of the plant.

Rose is the world's most recognized cut flower and one of India's most important commercial floriculture crops. This chapter provides comprehensive information on rose origin, taxonomy, genetics, breeding, varieties and commercial types. It emphasizes greenhouse production, including temperature, humidity, light, carbon dioxide, greenhouse orientation, planting systems, pruning, training, fertigation and crop regulation. Major pests and diseases, harvesting stages, grading, postharvest treatment, vase life and yield are also covered. Modern greenhouse varieties and newly developed spray and standard roses demonstrate the diversity of cultivars available for premium markets. The chapter is particularly valuable for commercial and export-oriented rose production.

Rose is one of the most important and versatile flower crops, with a distinct role in both loose and stemmed flower production. Loose roses are harvested as fully open flowers for garlands, religious offerings, cosmetics and numerous value-added products. The chapter discusses the traditional importance of rose in India and its applications in rose water, gulkand, essential oil, concrete, absolute, incense and other products. It covers origin, distribution, genetics, botanical characteristics and commercially important varieties. Production practices include climate and soil requirements, propagation, planting, nutrient management, irrigation, pruning and pest and disease management. Harvesting, postharvest handling, yield and value-addition opportunities are also discussed.

For a researcher, laboratory is another home where he/she spends much time every day. As we take care of cleanliness, safety, and design of our home, we must take care on these aspects of laboratory too. It is the responsibility of the laboratory personnel to ensure cleanliness/safety of the laboratory. Since every laboratory chemical and equipment have the potential to cause harms if not used with appropriate precautions. Hence, as a laboratory user, it is our responsibility to follow the basic safety/biosafety rules and regulations set up by the Principal Investigator of the laboratory, Institutional Biosafety Committee, as well as by other regulatory authorities, if any. We must be aware of the general/personal protective measures, cleanliness and laboratory waste disposal prior to joining a research laboratory. In this chapter we will briefly discuss about personal safety, chemical safety, cleanliness, waste disposal, etc.

A. Personal Safety

1. Personal Protective Equipment (PPE)

Personal protective equipment (PPE) is special arrangement to protect the worker from specific hazards because of using a hazardous substance. PPE does not reduce or eliminate the hazard, but protects the wearer from exposure to hazardous material. PPE should not be reused or brought outside the laboratory as these might increase the risk of spread hazardous material or contamination. Used PPE must be kept inside the laboratory in a designated waste storage area adjacent to the work area.

Introduction

Accumulation of excess soluble salts in the root zone of soils resulting in partial or complete loss of soil productivity is a worldwide phenomenon. The problems of soil salinity are widespread in the arid and semi-arid areas but salt-affected soils also occur extensively in the sub-humid and humid climates particularly in the coastal regions where the ingress of sea water through estuaries and rivers and through ground water movement causes large scale soil and water salinisation. Soil salinity is also a serious problem in areas where ground waters of high salt content are the only source of water available for irrigation. By far the most serious problems of salinity are being faced in the irrigated, arid and semi-arid regions of the world. Our ability to manage salt-affected soils and waters both in the irrigated and in the unirrigated regions will constitute a major effort in meeting potential food requirements. The magnitude of the problem can be appreciated from the following.

Once a pest, pathogen or a weed has been detected in the introduced planting material, quarantine officials must make all efforts to disinfect/decontaminate the material and make it available for further exploitation in the country without undue delay. However, it may be kept in mind that treatments, which only reduce the inoculum, may be acceptable for general agricultural practices, but they are not acceptable in plant quarantine. For quarantine purposes, tolerances are zero and, therefore, no residual inoculum of exotic pests/pathogens must remain. Fullproof eradicative treatments are required to be employed before release of the planting material from quarantine.

16.1. Fumigation

Fumigation of the material under atmospheric or under reduced pressure has been found acceptable as a quarantine treatment against insects and mites. Fumigants like methyl bromide, HCN, phosphine and EDCT (ethylene dichloride + carbon tetrachloride mixture) are commonly used.

In general, fumigation with Methyl bromide at 48g/cubic metre for 24 hours at 21ºC or above or 32g/cubic metre for 2 hours at 21ºC or above is used based on the kind of infected material and the pest to be salvaged.

A Scanning electron microscope (SEM) is a type of electron microscope that images a sample by scanning it with a high-energy beam of electrons in a raster scan pattern. The electrons interact with the atoms that make up the sample producing signals that contain information about the sample’s surface topography, composition, and other properties such as electrical conductivity.

The types of signals produced by an SEM include secondary electrons, back-scattered electrons (BSE), characteristic X-rays, light (cathodoluminescence), specimen current and transmitted electrons. Secondary electron detectors are common in all SEMs, but it is rare that a singlemachine would havedetectors for allpossiblesignals. The signals result from interactions of the electron beam with atoms at or near the surface of the sample. In the most common or standard detection mode, secondary electron imaging or SEI, the SEM can produce very high-resolution images of a sample surface, revealing details less than 1 nm in size. Due to the very narrow electron beam, SEM micrographs have a large depth of field yielding a characteristic three dimensional appearance useful for understanding the surface structure of a sample.

Electron Microscopes are scientific instruments that use a beam of highly energetic electrons to examine objects on a very fine scale. This examination can yield information about the topography (surface features of an object), morphology (shape and size of the particles making up the object), composition (the elements and compounds that the object is composed of and the relative amounts of them) and crystallographic information (how the atoms are arranged in the object).

Electron Microscopes were developed due to the limitations of Light Microscopes which are limited by the physics of light to 500x or 1000x magnification and a resolution of 0.2 micrometers. In the early 1930’s this theoretical limit had been reached and there was a scientific desire to see the fine details of the interior structures of organic cells (nucleus, mitochondria...etc.). This required 10,000x plus magnification which was just not possible using Light Microscopes.

Summary
 
Although the concept of IPM, with emphasis on minimum use of pesticides: is well established and widely practiced in India, pest population still continue to be unabated, often reaching to alarming levels .Development of non chemical methods of pest control  as component of IPM tactics is a priority area of research today. Development of multiple resistance in larval stages against recommended insecticides ,spoiling of crop ecosystem with toxic chemicals and consequences of health hazards is the best alternative to control the pest in adult stage before they reproduce. Use of light trap is one such potential methods of control for the species known to be positively phototropic in adult stage. Rice is one of the most important cereal crop grown in different parts of world , serving as staple diet for millions of people . The losses due to insect pests in rice are very high and the pesticidal use in this crop is second highest after cotton in world .The positive feature of using light trap as IPM tool for survey ,monitoring , detection and control tool is that most of the insect pest species of rice are phototropic in nature and collected in sufficient numbers in light trap .Therefore use of light trap for imparting eco-integrity  by minimizing indiscriminate use of chemicals ,reduction of pest management cost and enhancement of farm income can be very useful for achieving the ultimate goal of sustainability in rice cultivation. 

Recombinant DNA is advancement in molecular technology which allows manipulation of genomes of higher organisms and dissection of their complex regulatory circuits. This new methodology is being used to understand the biochemistry of living organisms. The isolation of gene begins with the cloning of fragmented DNA of the organism into appropriate vector.