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Food grains in India achieved an all-time high production (310.74 mt) during 2020-21. Varietal and seed replacement rates played an important role in achieving this milestone. A total of 1646 varieties of food crops comprising 1273 of cereals and 373 of pulses were released from 2011 to 2022. Of these 977 varieties consisting of cereals (667) and pulses (310) have been inducted into the seed chain during 2020-21. New breeding technonologies such as bio-fortification of food crops and marker-assisted breeding were applied to improve crop varieties with respect to specific desirable traits. A total of 65 bio-fortified varieties comprising rice (8), wheat (28), maize (14), pearl millet (9), finger millet (3), little millet (1) and lentil (2) have been released with improved levels of proteins, essential amino acids (lysine, tryptophan), vitamins (pro-vitamin A) and micro/macro-nutrients (zinc, iron, calcium). Marker-assisted breeding adopting foreground and background selections with targeted gene(s) utilizing molecular markers such as RFLPs, SSRs, CAPs, STS and INDEL resulted in to the development and release of 66 cultivars comprising rice (43), wheat (5), maize (10), pearl millet (2) and chickpea (6) with one/and or combination of traits such as tolerance to biotic/abiotic stresses, herbicide tolerance, nutrient use efficiency, earliness, nutritional and other quality traits. These non-genetically modified crop varieties are expected to play vital role in achieving food and nutrition security in India. The paper also provides insight in to the maintenance breeding of food crops. The analysis of seed requirement and availability during 2010-11 to 2020-21 revealed that seed requirements for cereals and pulses have increased consistently by 31.6% and 62.3%, from 186.8 to 245.8 lakh q and 22.3 to 36.2 lakh q, respectively. The production of rice, wheat, maize, pearl millet and pulses during 2020-21 increased over that of 2010-11 by 27.4%, 26.0%, 45.2%, 4.4% and 41.3%, respectively. The productivity of sorghum was higher by 18.9% over that of 2010-11 but production decreased by 31.7% on account of a reduction in acreage by 42.5% during the corresponding period. The net per capita availability of food grains increased, by 17.2% from 159.5 kg to 187.0 kg during this period. The cereals and pulses production needs to be up-scaled by 5.3% and 24.4% to meet the demand by 2030 from 285.28 mt and 25.46 mt, respectively, in 2020-21, with almost the similar acreage, degrading and depleting natural resources, thus, requiring a greater focus on enhancing yield/ha. Crop-specific breeding programmes should be accelerated with the adoption of new technologies like GM, gene editing, marker-assisted selection and speed breeding to address the challenges of climate change and degrading natural sources.

Indian mustard [Brassica juncea (L.) Czern.] is a major edible oil crop of India. The Indian Council of Agricultural Research—National Bureau of Plant Genetic Resources (ICAR-NBPGR) and ICAR—Directorate of Rapeseed Mustard Research (DRMR) together conserve one of the largest global collection of Indian mustard germplasm comprising 5950 accessions which includes indigenously collected landraces, exotic accessions, breeding lines, Improved/released cultivars, registered genetic stocks and other type of material of unknown origin. However, only a small fraction of this huge collection has been deployed in the breeding programme due to lack of information on majority of accessions. The objective of this study was to develop a core collection of Indian mustard to enhance utilization of conserved germplasm in crop improvement programme. For this purpose, the accessions were characterized at one ideal site (Bharatpur) using 14 agro-morphological traits and the resultant data was analysed using three state-of-the-art core collection construction tools—MSTRAT, Power Core and Core Hunter 3 (CH3), to obtain three core sets each with 595 accessions. The quality of these core sets was evaluated and compared using two genetic distance based metrices (E-NE & A-NE), several summary statistics, Shannon diversity index, phenotypic correlations etc. The core collection generated using CH3 which optimized simultaneously for both representativeness and diversity was found the best in capturing the genetic variation existed in the base collection for all the 14 traits. The diversity represented in the core collection will therefore, be a guideline to breeders for a wider use of the Indian mustard genetic resources available in the genebank for identification and introgression of new useful traits, as well as for delineation of their genetic basis particularly through marker-trait association.

Oilseed Brassica crops play an important role in the vegetable oil economy of India and the world. There is an urgently felt need to increase their yield levels across varying growing conditions to meet the ever-growing demand for edible oil. The production level fluctuates widely over time and space mainly due to the challenges posed by various biotic and abiotic stresses. To combat these stresses that are very complex in nature, we need to have multi-pronged strategy by combining agronomical and breeding approaches. A major shift in yield level of any crop plant with increased tolerance to biotic and abiotic stresses is possible only with extensive genetic manipulation through breeding, and the breeding efforts in turn will require the continued collection, conservation, evaluation, and deployment of diverse crop genetic resources in a targeted way. Various activities enshrined in the management of rapeseed-mustard genetic resources are systematically explained in this chapter with an aim firstly to sensitize the readers about the importance of PGR and then to explain the principles and methodologies underlying the various activities involved in PGR management with special emphasis on rapeseed-mustard group of crops. Status of rapeseed-mustard germplasm in India and the world in terms of their number, characterization, evaluation, utilization so far, and future thrust area required are also discussed in this chapter.

Genetic diversity evaluation is one of the most important components of pre-breeding, which provides a clear understanding about the structure and variability inherited in a crop and thus helps in the identification of genetically diverse parents for breeding programmes. Rapeseed-mustard (RM) group of crops constitutes six economically important crops, of which five are oilseed crops and one, that is, Brassica oleracea, is an important vegetable crop. Among oilseed Brassica species, B. juncea (Indian mustard) is the most widely cultivated crop in many countries including India, Canada, Russia, China and Australia. In India, this crop contributes to more than 85% of RM acreage. Various efforts had been made in the past for genetic diversity characterization in Indian mustard germplasm and varieties using agro-morphological and biochemical markers. With the development of genomic resources in oilseed Brassica species, emphasis had been focused on using DNA/molecular markers including randomly amplified polymorphic DNA (RAPDs), inter-simple sequence repeats (ISSRs), restriction fragment length polymorphisms (RFLPs), amplified fragment length polymorphisms (AFLPs), simple sequence repeats (SSRs) and expressed sequence tags (ESTs). In this chapter, we have tried to compile various studies conducted for genetic diversity evaluation in Indian mustard using different types of molecular markers.

Brassica rapa (2n = 20, AA genome) is an important oil yielding species of the family Brassicaceae and characterized by wide range of genetic and morphological subtypes suitable for cultivation under diverse agro-climatic regions of India. In this study, genetic diversity among three subspecies of B. rapa including yellow sarson, toria and outlier brown sarson was estimated using various agro-morphological traits and simple sequence repeat (SSR) markers. Maximum variability was recorded for siliqua angle (Coefficient of variation = 30.9%), followed by seeds/siliqua (CV = 18.8%), leaf length (CV = 10%) and plant height (CV = 16.8%). Principal component analysis explained more than 50% of the total observed morphological variability for first two components. Of the 107 SSR markers tested, 80 generated reproducible, clear and distinct amplicons of which, 65 (81.25%) were found polymorphic. The number of alleles at each locus ranged from 2 to 7, with an average of 3.03 alleles per marker. A total of 197 alleles were detected at 65 SSR loci with average PIC value of 0.457 and a mean resolving power of 3.04. Neighbor-Joining cluster analysis based on morphological traits and SSR markers separately classified all the 28 genotypes into five major groups. The population structure analysis resulted into three sub-populations with certain extent of admixture among the earlier established taxonomic sub-groups. Twenty-three unique alleles were detected in thirteen B. rapa varieties. The clustering analysis and principal coordinate analysis outlined the genetic relationships among different varieties belonging to the three subspecies of B. rapa. Genetically diverse genotypes as illustrated by score plots and from the clustering patterns brought out the wide range of diversity present among B. rapa genotypes and the underlying options available for selecting parental genotypes for hybridization and developing high yielding cultivars suitable for Indian conditions.

Genetic engineering offers one of the most potential techniques for modification of many horticulturally important traits, which have been found impossible so far to incorporate in elite backgrounds via conventional breeding methods without affecting their phenotypic traits. Thus this technique assists in circumventing the problems of a long generation period, which hampers the scope of genetic improvement particularly in perennial horticultural tree species. Advancements in molecular biology and genetic transformation have made it possible to identify, isolate, and transfer desirable genes from any plants or microbes. The introduction or enhancement of desirable traits is traditionally done by breeding. This is time consuming and also not very precise. On the other hand, genetic engineering creates plants with specific changes in the background of a proven cultivar without disturbing their genetic constitution. Expression of undesirable genes can be blocked by the application of antisense gene technology and RNAi technology. Biotechnological interventions that could increase the efficiency of horticultural crop improvement are essential to generate plants with several desirable traits.

Genetic engineering technique offers myriads of applications in improvement of horticultural crops for biotic and abiotic stress tolerance, and produce quality enhancement. During last two decades, a large number of transgenic horticultural crops has been developed and more are underway. A number of genes including natural and synthetic Cry genes, protease inhibitors, trypsin inhibitors and cystatin genes have been used to incorporate insect and nematode resistance. For providing protection against fungal and bacterial diseases, various genes like chitinase, glucanase, osmotin, defensin and pathogenesis-related genes are being transferred to many horticultural crops world over. RNAi technique has been found quite successful in inducing virus resistance in horticultural crops in addition to coat protein genes. Abiotic stresses such as drought, heat and salinity adversely affect production and productivity of horticultural crops and a number of genes encoding for biosynthesis of stress protecting compounds including mannitol, glycine betaine and heat shock proteins have been employed for abiotic stress tolerance besides various transcription factors like DREB1, MAPK, WRKY, etc. Antisense gene and RNAi technologies have revolutionized the pace of improvement of horticultural crops, particularly ornamentals for color modification, increasing shelf-life and reducing post-harvest losses. Precise genome editing tools, particularly CRISPR/Cas9, have been efficiently applied in tomato, petunia, citrus, grape, potato and apple for gene mutation, repression, activation and epigenome editing. This review provides comprehensive overview to draw the attention of researchers for better understanding of genetic engineering advancements in imparting biotic and abiotic stress tolerance as well as on improving various traits related to quality, texture, plant architecture modification, increasing shelf-life, etc. in different horticultural crops.