Not Available

Not AvailableHost and pathogens have to cope with different types of environmental stresses during their developmental processes. Autophagy regulates programmed cell death as a response to pathogen infection and is emerging as key a defense module in host-pathogen interactions. The current study focuses on the differential pattern of expression of autophagy (ATG) genes in two contrasting banana genotypes, upon infection with fungal pathogen Fusarium Oxysporum f.sp. cubense (Foc1). The expression analyses of twelve ATG genes responding to biotic stress were investigated in the contrasting genotypes “Calcutta-4” (tolerant) and “Kadali” (susceptible). All the 12 ATG genes were upregulated in both contrasting genotypes, upon disease progression. After Foc1 infection, it was observed that the susceptible genotype “Kadali” showed an enhanced expression at 3dpi, in comparison to the tolerant genotype. An increased and sustained expression of ATG genes in tolerant genotype “Calcutta-4” at 10dpi was also observed suggesting accelerated defense response, under Foc1 infection, indicating an important role of autophagy in disease tolerance to regulate programmed cell death which is a key component of plant immunity response. The present survey suggests that both increased and sustained higher expression of ATG genes during disease progression, imparts tolerance to Foc1 in banana.Not Availabl

Genomic Approaches for Improvement of Tropical Fruits: Fruit Quality, Shelf Life and Nutrient Content

The breeding of tropical fruit trees for improving fruit traits is complicated, due to the long juvenile phase, generation cycle, parthenocarpy, polyploidy, polyembryony, heterozygosity and biotic and abiotic factors, as well as a lack of good genomic resources. Many molecular techniques have recently evolved to assist and hasten conventional breeding efforts. Molecular markers linked to fruit development and fruit quality traits such as fruit shape, size, texture, aroma, peel and pulp colour were identified in tropical fruit crops, facilitating Marker-assisted breeding (MAB). An increase in the availability of genome sequences of tropical fruits further aided in the discovery of SNP variants/Indels, QTLs and genes that can ascertain the genetic determinants of fruit characters. Through multi-omics approaches such as genomics, transcriptomics, metabolomics and proteomics, the identification and quantification of transcripts, including non-coding RNAs, involved in sugar metabolism, fruit development and ripening, shelf life, and the biotic and abiotic stress that impacts fruit quality were made possible. Utilizing genomic assisted breeding methods such as genome wide association (GWAS), genomic selection (GS) and genetic modifications using CRISPR/Cas9 and transgenics has paved the way to studying gene function and developing cultivars with desirable fruit traits by overcoming long breeding cycles. Such comprehensive multi-omics approaches related to fruit characters in tropical fruits and their applications in breeding strategies and crop improvement are reviewed, discussed and presented here

Not Available

Not AvailableAbelmoschus esculentus L. (Malvaceae), populary known as okra, is one of the important pod vegetable crops in tropics and subtropics. To develop the microsatellite markers, we have partially sequenced genomic DNA using Roche 454 Titanium pyrosequencing technology. A total of 979,806 bp data from 61,722 reads were obtained. These reads were assembled into 3735 contigs of which 2708 had microsatellites. Primers were designed for 402 microsatellites, from which 50 randomly selected SSR primers were standardized for amplification of okra DNA. Genetic analysis was done by employing 29 genotypes. Polymorphic information content (PIC) across all 50 loci ranged from 0.000 to 0.865 with a mean value of 0.519. The observed and expected heterozygosity ranged from 0.000 to 0.750 and 0.000 to 0.972, respectively. Alleles per locus ranged from 1 to 27. This is the first report on the development of genomic SSR markers in okra using next-generation sequencing technology. We have also assessed cross species transferability of microsatellite markers with related wild species A. tetraphyllus (84%), A. ficulneus (78%), A. moschatus (92%), A. angulosus grandiflorus (90%) and A. caillei (86%), and demonstrated their use in genetic relatedness study and molecular characterization.Not Availabl

Identification of novel microsatellite markers in okra (Abelmoschus esculentus (L.) Moench) through next-generation sequencing and their utilization in analysis of genetic relatedness studies and cross-species transferability

Not AvailableAbelmoschus esculentus L. (Malvaceae), populary known as okra, is one of the important pod vegetable crops in tropics and subtropics. To develop the microsatellite markers, we have partially sequenced genomicDNA using Roche 454 Titanium pyrosequencing technology. A total of 979,806 bp data from 61,722 reads were obtained. These reads were assembled into 3735 contigs of which 2708 had microsatellites. Primers were designed for 402 microsatellites, from which 50 randomly selected SSR primerswere standardized for amplification of okraDNA. Genetic analysis was done by employing 29 genotypes. Polymorphic information content (PIC) across all 50 loci ranged from 0.000 to 0.865 with a mean value of 0.519. The observed and expected heterozygosity ranged from 0.000 to 0.750 and 0.000 to 0.972, respectively. Alleles per locus ranged from 1 to 27. This is the first report on the development of genomic SSR markers in okra using next-generation sequencing technology. We have also assessed cross species transferability of microsatellite markers with related wild species A. tetraphyllus (84%), A. ficulneus (78%), A. moschatus (92%), A. angulosus grandiflorus (90%) and A. caillei (86%), and demonstrated their use in genetic relatedness study and molecular characterizationNot Availabl

Not Available

Not AvailableIn this study, genetic diversity and population structure of mango cultivars were assessed by employing fourteen simple sequence repeat markers, with high polymorphic information content. A set of 387 mango accessions from different regions of India was used. Model-based structure analysis revealed the presence of two subpopulations comprising the cultivars from ‘South-West’ region and ‘North-East’ region. A similar clustering pattern was observed in the dendrogram analysis, with two major groups identified that were further sub-grouped based on their genetic relatedness. Analysis of molecular variance showed a significant variance component among and within mango sub-populations derived from the structure analysis. The proportion of genetic differentiation among individuals within the two populations was found to be significant with a FST value of 0.248. The extent of genetic diversity was found to be higher in case of ‘South and West’ population than ‘North and East’ population. Six SSR loci with low probability of identity values have been chosen as universal markers for mango characterization. Our results highlight genetic diversity encompassed by mango cultivars and genetic distinctness of ‘South-West’ and ‘North-East’ region cultivars.Not Availabl

Not Available

Not AvailableIn this study, genetic diversity and population structure of mango cultivars were assessed by employing fourteen simple sequence repeat markers, with high polymorphic information content. A set of 387 mango accessions from different regions of India was used. Model-based structure analysis revealed the presence of two subpopulations comprising the cultivars from ‘South-West’ region and ‘North-East’ region. A similar clustering pattern was observed in the dendrogram analysis, with two major groups identified that were further sub-grouped based on their genetic relatedness. Analysis of molecular variance showed a significant variance component among and within mango sub-populations derived from the structure analysis. The proportion of genetic differentiation among individuals within the two populations was found to be significant with a F ST value of 0.248. The extent of genetic diversity was found to be higher in case of ‘South and West’ population than ‘North and East’ population. Six SSR loci with low probability of identity values have been chosen as universal markers for mango characterization. Our results highlight genetic diversity encompassed by mango cultivars and genetic distinctness of ‘South-West’ and ‘North-East’ region cultivars.Not Availabl