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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.

Plants respond through a cascade of reactions resulting in varied cellular environment leading to alterations in the patterns of protein expression resulting in phonotypic changes. Single cell genomics and global proteomics came out to be powerful tools and efficient techniques in studying stress tolerant plants. Non-coding RNAs are a distinct class of regulatory RNAs in plants and animals that control a variety of biological processes. Small ncRNAs play a vital role in post transcriptional gene regulation by either translational repression or by inducing mRNA cleavage. The major classes of small RNAs include microRNAs (miRNAs) and small interfering RNAs (siRNAs), which differ in their biogenesis. miRNAs control the expression of cognate target genes by binding to complementary sequences, resulting in cleavage or translational inhibition of the target RNAs. siRNAs too have a similar structure, function, and biogenesis like miRNAs but are derived from long double-stranded RNAs and can often direct DNA methylation at target sequences.In this review, we focus on the involvement of ncRNAs in comabting abiotic stresses of soybean. This review emphasis on previously known miRNAs as they play important role in several abiotic stresses like drought, salinity, chilling and heat stress by their diverse roles in mediating biological processes like gene expression, chromatin formation, defense of genome against invading viruses. This review attempts to elucidate the various kinds of non-coding RNAs explored, their discovery, biogenesis, functions, and response for different type of abiotic stresses and future aspects for crop improvement in the context of soybean, a representative grain legume.

Faba bean (Vicia faba L.) maintain third place with respect to area and production among legume. Its unique ability to excel under all most all type of climatic conditions, it is one of the best performing crops under changing climate scenario. Its soil fertility augmenting potential and their performance was evaluated for two years with 73 accessions collected from Bihar. This study provides glimpses of scope and magnitude of soil fertility improving potential of faba bean (Vicia faba L.)

In the changing climatic conditions and global scenario, in a continued green revolution; we have already accomplished food security and is legal through food security bill. Whereas, Systematic Management of Agricultural Resources and Technology (SMART) is the only way to nutritional security. India started breathing for agriculture with 30 Crore people (300 million) in the 1950's when we faced a huge food shortage and had to receive food under PL 480 agreement with the United States. Farmers brought us up from a net importer of food grains in 1950s, to an exporter; a huge jump. Whereas now again there is a shortage for pulses and oilseeds though we are having enough of cereals. What went wrong? We do have sufficient genetic diversity, we do have high yielding varieties, we have farmer supporting systems, but we were not SMART enough. Indian agriculture has registered impressive growth over last few decades with the same momentum of continued green revolution. Recent past has registered highest production levels in horticultural and fishery, animal husbandry products. The food grain production has increased from 51 million tonnes (MT) in 1950-51 to 265.57 MT during 2013-14 highest ever since independence. Even during 1950's we were the largest producers and exporters of many agricultural produce. At present, we have lost the first places in production of so many crops to our neighbours. It need not to be a monopoly but we should know our potential and at least to maintain the production level rather than giveup. So wise is the farmer, rich will be our nation. Hence, come on farmers raise up! We are your dependants! Self sufficiency has to be counted from the root level. If not at the level of an individual farmer, it should be from villages. A village should produce its needs starting from solar energy to food grain, milk, vegetables and feeds reducing the burden on transport and transportation loss. There is lack of 'we-feeling' or 'togetherness' in farm villages which cannot be created but can be inculcated in their minds for a better livelihood.