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Advances in molecular biology have sharpened the tools of the breeders, and brighten the prospects of confidence to serve the humanity. The application of biotechnology to field crop has already led to the field testing of genetically modified crop plants. Genetically engineered Rice, Maize, Soybean, Cotton, Oilseeds like Rape seed, Sugar Beet and Alfalfa cultivars are expected to be commercialized in the late of 20^th century. Genes from varied organisms may be expected to boost the performance of crops especially with regard to their resistance to biotic and abiotic stresses

Genetic engineering involves isolation of DNA fragments within a cell recombining them outside. The basic technique is quite simple. Two DNA molecules are isolated and cut into fragments by one or more specialized enzymes, the fragments joined together in a desired combination, then restored to a cell from replication and reproduction. This method also referred to as recombinant DNA technology. Genetic engineering developed in the mid 1970 when it becomes possible to cut DNA and to transfer particular pieces of DNA containing specific bits of information, from one type of organism into other.

Introduction

It refers to all activities designed to identify materials that cannot be used directly in breeding programmes, and further to transfer these traits to an intermediate set of materials that breeders can use further in producing new varieties for farmers. It is a bridge between Genetic Resources and Crop Improvement. That is collaboration between germplasm curator and plant breeder.

Crosses between adapted and exotic materials, where different proportions of introgression are obtained and evaluated, have been denominated as semi exotic materials. That should be readily used in regular breeding programme for cultivar development.

Objectives of pre-breeding 8-10 Years • Improved germplasm and associated genetic knowledge that enhance resistance expression and diversity.

• Reduce genetic uniformity in crops through the use of a wider pool of genetic material to increase yield, resistance to pests and diseases, and other quality traits.

• Identification of desirable traits/genes and their subsequent transfer into a suitable set of parents for further selection.

• Improved parental stocks which can be readily utilized within breeding programs and improved selection methodologies.

• Identify potentially useful genes in a well-organized and documented gene bank Designing strategies that lead to development of an improved germplasm that are ready to use in varietal development.

ABSTRACT

Of the several PCR techniques developed during the last two decades, random amplified polymorphic DNA (RAPD) offers a simple and economical means of genotype characterization. The information obtained through RAPD characterization is extensively used for the identification of genotypes, screening of duplicates, assessing genetic diversity and monitoring the genetic stability of conserved germplasm. The present study is a report on the DNA fingerprinting of P. nigrum and P. longum cultivars. Fourteen land races and three advanced cultivars of P. nigrum and eleven land races and one advanced cultivar of P.longum were used in the present study. Forty decamer primers from Operon Tech were screened using two representative genomic DNA samples of black pepper. Of these, 10 primers that yielded clear and dominant band patterns were selected for the final analysis of the 29 accessions. These generated 119 amplification products. The total number of markers per primer varied with respect to both P. nigrum and P. longum. Cultivar specific single bands were obtained for a few land races and accessions of both the Piper species.

Introduction
Chromosome manipulation, the targeted alteration of chromosome quantity and combination, represents a cornerstone of genetic enhancement in aquaculture. Initially rooted in early twentieth-century studies focused on fundamental biology—particularly in amphibian models—this field has significantly expanded to enhance desirable traits through methods like polyploidy and uniparental inheritance (Arai, 2001; Benfey, 1999; Benfey, 2011; Cherfas, 1975; Devlin & Nagahama, 2002; Felip et al., 2001; Guo et al., 2009; Hulata, 2001; Komen & Thorgaard, 2007; Nagy, et al., 1979; Nagy, et al., 1978; Neyfakh, 1956; Ojima & Makino 1978). Over time, researchers worldwide have meticulously refined these techniques, transforming chromosome manipulation into a powerful tool for developing aquaculture strains with improved performance traits. By the late 20th century, aquaculture research began leveraging chromosomal modifications in finfish and aquatic invertebrates to achieve increased growth rates, disease resistance, and enhanced survival, with such techniques becoming extensively applied in commercial aquaculture operations (Pandian & Koteeswaran, 1998; Piferrer et al., 2009; Purdom, 1972). Over the past 30 years, a wide body of research has focused on optimizing treatment conditions specific to each target species, yielding robust evaluations of various aquaculture performance metrics. These metrics, including survival, growth, reproductive maturation, and disease resistance, have proven essential in assessing the effectiveness of polyploid and uniparental (gynogenetic and androgenetic) progeny (Purdom, 1976; Refstie et al., 1977; Romashov et al., 1960; Romashov & Belyaeva 1964; Stanley 1976; Stanley, 1976; T. J. Pandian, 2011; Devlin & Nagahama 2002; Guo, et al., 2009; Hulata, 2001; Komen & Thorgaard, 2007). As aquaculture has grown into the fastest-expanding sector of animal food production globally, the demand for sustainably produced, high-quality protein continues to rise. This surge in demand is driven, in part, by the decline of global fisheries due to overfishing, pollution, and habitat degradation. Consequently, the aquaculture industry faces the challenge of increasing output sustainably, necessitating the development of improved fish strains that support the resilience and efficiency of farmed stocks. To meet these demands, a range of genetic modification methods has been employed, aiming to produce fish with desirable traits such as rapid growth, superior meat quality, and enhanced resistance to disease (Xu et al., 2015). Chromosome manipulation has thus emerged as a critical tool, facilitating precise genetic interventions to enhance farmed species’ overall performance and adaptability.

Introduction

Agricultural biodiversity must be an integrated part of climate change adaptation and mitigation efforts. Climate change adaptation, biodiversity conservation and poverty alleviation should complement each other (FAO, 2007, 2008). Climate affects vectors, pathogens, hosts and host-pathogen interactions from the level of cellular defence to that of the habitat. Hoberg et al. (2008) provide an overview of predicted responses of complex host-pathogen systems to climate change. Climate change may affect the spatial distribution of disease outbreaks, and their timing and intensity (Epstein 2001). Outbreaks of African horse sickness, peste des petits ruminants, Rift Valley fever, bluetongue virus, facial eczema and anthrax are triggered by specific weather conditions and changes in seasonal rainfall profiles.

Dairy farmers are faced with a number of fundamental inquiries. The first inquires as to what dairy animal he needs to keep. Is the breed with the best production performance the one that has adapted to the local environment the most? What animal is the best, asks the second? Is it the one with a showwinning conformation or the one with a strong ancestry? Is the ideal dairy cow one that produces the most milk, has the best feet, legs, and udder support, or combines the performance of these characteristics in the best possible way?

Buffaloes have been classified in two main categories namely riverine and swamp buffaloes depending upon variation in their habitat and genome structure. River buffaloes are generally large in size mostly with curled horns and are mainly found in India, Pakistan and some of the west Asian countries, prefer to enter clear water and have 50 (2n) numbers of chromosomes and are primarily used for milk production and also used for meat production and draught power. Swamp buffaloes are stocky animals with marshy land habitats and have 48 (2n) numbers of chromosomes. They were primarily developed for draught power in paddy fields and haulage and are also used for meat and milk production. Swamp buffaloes are mostly found in south East Asian countries and few animals are also available in north eastern states of India.

Cocoa (Theobroma cacao L.) represented as ‘Food of Gods’ is considered as an important beverage crop next to Tea and Coffee. The economic produce of cocoa is the bean, when it is fermented and dried, become the source for chocolate. Cocoa is native to Amazon basin of South America and is domesticated and distributed to different regions by the natives Mayas, Aztecs and Pipil- Nicaraos (Wood and Lass, 1955; Young, 1994) who consumed it as an energy drink called ‘xocoatl’ by roasting and grinding cocoa beans. When Spanish conquered Mexico in 16th century they took cocoa to Europe which is christened as ‘chocolate’ the worlds’ favourite food. From then on cocoa spread to many other countries (Wood, 1991). According to World Cocoa Foundation, currently 40–50 million people depend on cocoa for their livelihood and the production is 3.97 mt in which Africa contributes 71%, Latin America 14% and Asia and Oceania 14% (Jean Marc Anga, 2013). Ivory Coast is the major producer followed by Ghana, Cameroon, Nigeria and Brazil. In Asian continent, Indonesia and Malaysia are the leading producers (www.wcf.org.).

Abstract

The genetic improvement of crop plants is possible only through employing an appropriate breeding technique. The use of plant breeding technique depends on mode of pollination and reproduction of plant species e.g. selection and hybridization are used in sexually reproduced species, while clonal selection in asexually propagated plant species. The plant species/ varieties are usually derived through conventional techniques (vi z. introduction, selection, hybridization etc.), which are commonly used in various breeding programmes, while some modern techniques viz. transgenic breeding and marker assisted selection etc. are also available which are equally effective for improvement of all crop species. Various techniques applied for development of new varieties and hybrids are briefly described in this section.

Plant breeding is an art, science and technology of improving genetic make-up of crop plants in relation to their economic usefulness for mankind. Various techniques/methods of breeding used for genetic improvement of crop plants are: introduction, selection, hybridization, mutation, transgenic breeding etc.

Classification of Breeding Techniques: Plant breeding techniques are classified as conventional and modern breeding techniques.

Livestock is one of the fastest growing agricultural subsectors in developing countries. In India has a vast diversity of animal genetic resources. Among them, sheep is an important ‘five star’ livestock species contributing significantly to rural economy through production of mutton, wool, manure, skin and milk etc. Sheep make a valuable contribution to the livelihood of the economically weaker sections of the society. The total Livestock population is 535.78 million and total sheep population is 74.26 million in in the country showing an increase of 4.6% and 14.1%, respectively over Livestock Census-2012. And it’s ranking 3rd in the world after China and Australia. Rajasthan is the fourth largest sheep rearing state in India with 7.9 million population (Livestock Census, 2019). Malpura sheep is one amongst the heaviest sheep breed of India, widely distributed in the semi-arid region of Rajasthan, mostly Tonk, Jaipur and Sawai Madhopur districts. Malpura sheep is reared and improved for mutton production since year 1975 at CSWRI, Avikanagar. The objective since then has been to improve the growth characteristics of this sheep breed for producing more carcass yield.The sheep is known for its adaptability to the harsh environment and potential for high meat production.Coat colour of Malpura sheep is white with coarse wool. The face is light brown with short, blunt ears. Animals have square compact body and long legs. Farmers also have liking for the long tail of animals for aesthetic purpose. The farmers like Malpura sheep for its properties like good mothering ability and produce sufficient milk to sustain and accelerate the growth of their neonates (Mishra et al., 2005), higher weight gain, number of lambs weaned, wool quality, walking capacity and the ease of management.

As the ornamental fish industry expands throughout the world, genetic considerations have become more important in terms of production, sustainability and conservation. Genetic technologies are now being applied to increase food production in aquaculture through traditional and modern breeding programmes. Genetic markers can help to manage capture fisheries and distinguish farmed from wild stocks in mixed fisheries. Genetic technologies are also now finding application in post-harvest and trade to assist in product identification and traceability. Genetic improvement of fish has considerably increased the fish production from aquaculture. It includes selective breeding, hybridization, polyploidy, gene and nuclear engineering. For any genetic selection programme, induced breeding is the basic and initial step. Intensive selective breeding is practiced with various species of fish in perfecting appearance, shape and color so that new strains are produced.

Domestication

Most of the fish being widely grown in captivity are domesticated to some extent, but there are very few which have undergone genetic improvement. Just as terrestrial livestock and crops are bred to be not only productive, but productive in convenient proximity to humans, aquatic plants and animals are now undergoing these same pressures.

In comparison to agriculture crops, fruit plants and animals, aquaculture is much behind with regard to the domestication of the fish, especially ornamental fish. Never the less, a good number of ornamental fish have been domesticated which can be considered for selective breeding to improve their traits. The available technologies and tools could be used to remarkably speed up domestication and genetic improvement process.

Domestication implies much more than merely keeping wild animals in farms or homes. Domestication is a very long process, during which captive individuals become more adapted to captive environments. Domestication leads to permanent genetic modifications of a bred lin-eage, while taming or keeping wild fish in captive conditions is only conditioned behavioral modification of individuals. The entire life cycle of the domesticated fish species must be fully closed in captivity. Once full life cycle is completed in captivity, the process of domestication can proceed further.

The first truly domesticated fish species was certainly the goldfish, for which the domestication was initiated by the Chinese about 1500-2000 years ago.

Technologiocal intervention is essential for improving pulse productivity through introduction of suitable high yielding varieties (Masood Ali and Shiv Kumar 2009). This is only possible through: (i) development of high yielding varieties with multiple resistance/tolerance to major diseases like mung bean yellow mosaic virus (MYMV), powdery mildew (PM) and Cercospora in mung bean and urdbean; (ii) development of varieties having resistance and tolerance to pre-harvest sprouting in mung bean, (iii) development of efficient plant type with high biomass and harvest index, (iv) development of varieties suited for intercropping system, (v) broadening genetic base of developed varieties, (vi) development of 50-55 days varieties of mung bean having 1 tonne/ha productivity and resistance to YMV for summer cultivation, (vii) development of high yielding and early maturity varieties of peas having resistance to powdery mildew, (viii) developing rajmash genotypes resistant to bean common mosaic virus and sclerotia rot, tolerant to high/low temperature and shattering resistance are important ones for increasing production through varieties intervention (AICRP MuLLaRP, http://iipr.res.in/mullarp).

The Para rubber tree (Hevea brasiliensis) is the most important commercial source of natural rubber, a strategic raw material. Rubber is an indispensable commodity used in the manufacture of over 50,000 products worldwide. This crop has therefore emerged as a key plantation species in various countries. The global area under rubber  cultivation is about 9.6 million hectares producing 9.2 million tones annually (IRSG, 2014). Among the major natural rubber producing countries, India occupies 4th position in terms of production with 0.91 million tones and more significantly the first position in average productivity of 1823 kg/ha/year. The major rubber producing countries are Thailand, Indonesia, India, Malaysia, Vietnam and Sri Lanka. Rubber is also commercially cultivated in Philippines, Nigeria, Cameroon, Cote de Ivoire, Liberia, Brazil, Cambodia, Nigeria, Cameroon, Guatemala, Myanmar, Mexico, China, Ghana, Democratic Republic of Congo, Gabon, and Papua New Guinea.Increase in production and improving productivity of NR continues to be the subject of considerable research efforts, particularly in the context of the widening gap between demand and supply of natural rubber. Over one million small farmers  in India owning less than 0.5 ha. of land depend on rubber cultivation for a livelihood.

Livestock is an important source of income for the rural poor and marginal farmers which enables earn income and food security using common resources.It is a best option to utilize such waste resources in proper way to earn income. About 65-69% of Indian population consisting of small and marginal farmers and land less laborers reared animal as supplementary occupation by feeding their animals agriculture by products. Indian agriculture is very difficult to sustain without dairy animals. Per capita availability of milk comes out to 281gm per day, which is below than the average of 300gm recommended by Nutrition Council of ICMR. Thus, there is a further need to increase the milk production of the country in view of minimizing difference between per capita availability and requirement. Milk production in India has increased from a modest 22 million tons during 1970-1971 to about 122 million tons in 2011—2012 (Deptt. of Animal Husbandry and Dairying).

ABSTRACT

Plant tissue culture is an important and efficient technique for the production of desired plant products with different and improved variety in aseptic conditions. Plant tissue culture methods have a wide scope for the creation, conservation, and utilization of genetic variability for the genetic improvement of field, fruit, vegetable, forest crops, medicinal and aromatic plants. The main objective of this communication were to collects the information and techniques of tissue culture to genetic improvement of the medicinal plants. Tissue culture technique in combination with molecular techniques has been successively used to incorporate specific traits through gene transfer. Modified varieties of medicinal plants is mostly required, as some compounds like alkaloids, terpenoids, steroids, saponins, phenolics, flavanoids, and amino acids etc are extracted from these plants. From the ancient time up to 20th century, most of the human-being are dependent on the medicinal plant for basic healthcare needs and improving such a crop is the most important for this billionaire world. As far conventional methods of genetic improvements the tissue culture techniques takes cheap and lesser time required for traits specific improvements in the MAPs.

Phenotype is a result of gene products brought to expression in a given environment. Genes specify the structure of proteins. All known enzymes are proteins. Enzymes perform catalytic function, causing the splitting or union of various molecules. All of the chemical reactions which occur in the cell constitute the subject of intermediary metabolism. These reactions occur as stepwise conversions of one substance into another, each group being mediated by a specific enzyme. All of the steps which transform a precursor substance to its end product constitute a biosynthetic pathway. Several genes are usually required to specify the enzymes involved in even the simplest pathways. Before gene-enzyme relationship could be postulated, soon after rediscovery of Mendelian principles of inheritance, it was discovered that genes were not merely separate elements producing distinct individual effects, but they could interact with each other to produce completely novel phenotypes. The simplest example of gene interaction could be the fact that allele A could be characterized by phenotype A, and the allele B by the phenotype B and an organism having both alleles A and B at the same time might show phenotype C. The occurrence of such interactions means that the phenotype we observe is not present in the genes themselves but arises from a complicated developmental process resulting from a biosynthetic pathway as illustrated below (Stansfield, 1969)

Introduction
Aquaculture is rapidly outpacing all other sectors in agricultural development. The study of fish genetics gained traction in the 20th century, driven by advancements in the understanding of Inheritance and reproduction. During the 1960s, selective breeding programmes aimed at enhancing genetic qualities became more common (Gjedrem and Baranski, 2009). Currently, more than 60 fish and shellfish species are going through selective breeding (Gjedrem and Baranski, 2009). Despite this, many critical traits like resistance to disease, efficiency of feed conversion, fatty acid composition and quality of meat are challenging to assess in breeding prospects but significantly impact the yield and profitability of several aquaculture species. Genetic mapping refers to the process of creating a genetic map (Van Ooijen and Jansen, 2013). Making genetic linkage maps is still essential for carrying out genetic and genomic research and many aquaculture species have had such maps developed. Developments in genotyping and sequencing technologies have made it the creation of higher-density, high-resolution (HR) genetic linkage maps. However, there are now important tasks in linkage analysis due to the usage of a large number of molecular markers. High-density linkage maps are valuable tools for studying genomic biology and evolutionary genetics because they serve as the foundation for QTL (quantitative trait loci) mapping. They facilitate the quantification of recombination rates, linkage disequilibrium levels, and chromosomal rearrangements across chromosomes, between sexes, and among different populations. The development of marker-Assisted Selection (MAS) has gained significant consideration and has significantly accelerated genetic breeding efforts in numerous cultured aquatic organism (Li, 2019; Yu, 2019). Quantitative trait loci (QTL) linked to economically important variables are frequently mapped using genetic linkage maps, which are an invaluable tool for examining genomic regions. (Huang, 2020; Wan 2017; Zhou, 2021). Growth rate, flesh quality, and disease resistance are only a few of the important features that are regulated by several genes or loci. The use of genetic maps in QTL (quantitative trait loci) mapping is essential for determining the locations of genes linked to these traits. (Huang, 2020; Li, 2019; Wan, 2017; Wang, 2018). The mapping of trait-related quantitative trait loci has been greatly improved by recent developments in high-throughput next generation sequencing techniques (You, 2020). Research in this field has greatly advanced through the use of a variety of techniques, including restriction site-associated DNA sequencing (RAD-seq), genotyping-by-sequencing, specific-locus amplified fragment sequencing, and genome-wide association studies (GWAS). Of these, RAD-seq is thought to be an appropriate, robust, and economical approach that has demonstrated 172 Aquaculture Genetics: Breeding, Conservation, and Sustainable Production efficacy in detecting genotypes and single nucleotide polymorphisms (SNPs) (Andrews, 2016). Linkage mapping in aquaculture is a valuable tool that has revolutionized selective breeding. By revealing the genetic foundations of key traits, it allows for more efficient and sustainable aquaculture practices. The integration of linkage mapping with other genomic technologies is expected to enhance productivity, improve disease management, and ensure the long term sustainable growth of aquaculture industries worldwide.

Linkage and Crossing Over

Crossing over may produce recombinant phenotypes.

Bateson and Punnett discovered two traits that did not assort independently.

Morgan provided evidence for the linkage of several X-linked genes and proposed that crossing over between X chromosomes can occur.

A chi square analysis can be used to distinguish between linkage and independent assortment.

Creighton and McClintock correlated crossing over that produced new combinations of alleles with the exchange of homologous chromosomes.

Crossing over occasionally occurs during mitosis. Genetic Mapping in Plants and Animals

The frequency of recombination between two genes can be correlated with their map distance along a chromosome

Alfred Sturtevant used the frequency of crossing over in dihybrid crosses to produce the first genetic map.

Trihybrid crosses can be used to determine the order and distance between linked genes.

Interference can influence the number of double crossovers that occur in a short region.