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In eggplant, two kinds of fruit‐bearing habits can be observed, that is, cluster and solitary. The fruits grown in cluster are small in size but contribute towards yield and productivity. In this investigation, we have studied the genetics of fruit‐bearing habit and identified the SSR markers linked to this trait. Pusa Safed Baingan 1 (cluster bearer) and Pusa Hara Baingan 1 (solitary bearer) having contrasting traits were crossed to generate F1 (20 plants), F2 (215 plants), B1 (73 plants) and B2 (64 plants). Genetic analysis of the trait was carried out using Chi‐square test. The segregation of plants in F2 suggested recessive epistasis with ratio of 9:3:4 (solitary: mixed: cluster) indicating involvement of two genes for controlling the fruit‐bearing habit. The parental polymorphic 6 SSR markers were used for genotyping F2 plants and co‐segregated with the fruit‐bearing habit (Bh1) locus in 1:2:1. A linkage map covering 63.86 cm distance was developed, the SSR marker emf11A03 was closest with a distance of 4.37 cm, emk03O04 at 12.5 cm distance, and emf21O06 at 14.5 cm. The physical positions of the SSR markers emb01J19 and emf11A03 flanking Bh1 gene were located at 4.77 mb position of contig Sme2.5_05721.1 and 5.18 Mb position of contig Sme2.5_00994.1, respectively. The findings in the present study will be helpful in marker‐assisted breeding to enhance yield in eggplant. [ABSTRACT FROM AUTHOR]

The development of nutrient-use efficient rice lines is a priority amidst the changing climate and depleting resources viz., water, land, and labor for achieving sustainability in rice cultivation. Along with the traditional transplanted irrigated system of cultivation, the dry direct-seeded aerobic system is gaining ground nationwide. The root-related traits play a crucial role in nutrient acquisition, adaptation and need to be concentrated along with the yield-attributing traits. We phenotyped an association panel of 118 rice lines for seedling vigour index (SVI) traits at 14 and 21 days after sowing (DAS), root-related traits at panicle initiation (PI) stage in polythene bags under controlled aerobic condition, yield and yield-related traits under the irrigated condition at ICARIIRR, Hyderabad, Telangana; irrigated and aerobic conditions at ARS, Dhadesugur, Raichur, Karnataka. The panel was genotyped using simple sequence repeats (SSR) markers and genome-wide association studies were conducted for identifying marker-trait associations (MTAs). Significant correlations were recorded for root length, root dry weight with SVI, root volume at the PI stage, number of productive tillers per plant, spikelet fertility, the total number of grains per panicle with grain yield per plant under irrigated conditions, and the total number of grains per panicle with grain yield per plant under aerobic condition. The panel was divided into three sub-groups (K = 3) and correlated with the principal component analysis. The maximum number of MTAs were found on chromosomes 2, 3, and 12 with considerable phenotypic variability. Consistent MTAs were recorded for SVI traits at 14 and 21 DAS (RM25310, RM80, RM22961, RM1385), yield traits under irrigated conditions (RM2584, RM5179, RM410, RM20698, RM14753) across years at ICAR-IIRR, grain yield per plant (RM22961, RM1146) under the aerobic condition, grain yield per plant at irrigated ICAR-IIRR and SVI (RM5501), root traits at PI stage (RM2584, RM80, RM410, RM1146, RM18472). Functionally relevant genes near the MTAs through in-silico expression analysis in root and panicle tissues viz., HBF2 bZIP transcription factor, WD40 repeat-like domain, OsPILS6a auxin efflux carrier, WRKY108, OsSCP42, OsMADS80, nodulin-like domain-containing protein, amino acid transporter using various rice expression databases were identified. The identified MTAs and rice lines having high SVI traits (Langphou, TI-128, Mouli, TI-124, JBB-631-1), high yield under aerobic (Phouren, NPK-43, JBB-684, Ratnamudi, TI-112), irrigated conditions (KR-209, KR-262, Phouren, Keibi-Phou, TI-17), robust root traits like root length (MoirangPhou-Angouba, Wangoo-Phou, JBB-661, Dissi, NPK-45), root volume (Ratnachudi, KJ-221, Mow, Heimang-Phou, PUP-229) can be further employed in breeding programs for the targeted environments aimed at improving seedling vigour, yield-related traits under irrigated condition, aerobic condition as adaptability to water-saving technology. [ABSTRACT FROM AUTHOR]

The present investigation was carried out to estimate indica-tropical japonica genome proportion in two newly developed wide compatible restorer lines (RP6367 and RP6368) derived through indica-tropical japonica crosses and to study the molecular diversity among 12 rice genotypes namely, five promising indica restorers (RPHR1005, RPHR1096, IBL57, DR714-1-2 and Akshayadhan), two maintainers (IR58025B and APMS6B), two newly identified wide compatible restorer lines (RP6367and RP6368), two typical tropical japonica lines (IRGC66651 and IRGC66577) and one typical indica genotype (Nagina22) using 50 SSR markers and 45 InDELs. Out of the 95 markers, 54 were found to be polymorphic. The genotypic data of 54 polymorphic markers was used to estimate indica-tropical japonica genome proportion in derived lines and molecular diversity among 12 genotypes. The percentage of tropical japonica genome proportion in derived lines RP6367 and RP6368 was found to be 50% and 55.55% respectively. Our results suggest that the proportion of tropical japonica in hybrid rice parental lines is the key to select the best parents for efficient utilization of the heterosis present between indica and tropical japonica subspecies. Out of the 54 markers, 19 markers recorded PIC value above 0.5 and can be considered as highly informative and useful to study molecular genetic diversity. In this study, the SSRs primers showed higher PIC values compared to InDels. It is concluded that the use of highly polymorphic molecular markers detected in this study gives a better understanding of genetic relationship among closely related rice genotypes. [ABSTRACT FROM AUTHOR]

Sheath blight disease of rice caused by Rhizoctonia solani is one of the most dreaded plant diseases faced by the rice farmers all over the world. None of the commercially cultivated rice varieties have sufficient level of field resistance, and the disease is presently being managed by chemical pesticides. In this study, 40 isolates of rice sheath blight pathogen, collected from diverse rice ecosystems from 12 different states of India, were characterized for their morphological, pathological and genetic variation. The isolates showed wide morphological variation in terms of size of sclerotia and abundance of sclerotia production. The virulence of each pathogen isolate was studied on four rice varieties, that is TN1, IR 64, Tetep and Swarnadhan in glasshouse, and observations were taken by measuring the relative lesion height. The relative lesion heights produced by these isolates on four different rice varieties varied widely. Genetic variation of the isolates was analysed using ISSR markers. The primers based on AG, GA, AC and CA repeats were informative and revealed polymorphism among the isolates. The polymorphism information content ( PIC) of the primers ranged from 0.80 to 0.96, while the resolving power ( Rp) ranged from 3.7 to 15.35. Largely, grouping of the isolates happened based on their geographical origin. One isolate from Titabar, Assam, and another from Adialabad, Telangana, were quite distinct from rest of the isolates. [ABSTRACT FROM AUTHOR]

SSR markers targeting (GATA) n motifs are known to be highly polymorphic and useful in many organisms. (GATA) n motif specific SSR markers covering the whole rice genome are not available. The present study was carried out with an objective to identify class I rice microsatellites in the rice genome with (GATA)n motifs, in-silico, and validate their potential as molecular markers. A total of 243 such motifs were identified; 65 of these were present in the genic region, 59 were in the upstream region and the remaining motifs were found in the intergenic regions. Many of the (GATA) n motifs were found within and/or upstream of genes associated with biotic or abiotic stress tolerance. A total of 230 PCR-based markers targeting all the class I (GATA) n microsatellites were developed and 35 of these markers spread across the rice genome were validated in a set of 24 representative rice varieties belonging to five distinct cultivar groups. All the markers were polymorphic, with average polymorphism information content (PIC) value of 0.61, and the rice cultivars could be uniquely distinguished into different cultivar groups based on marker analysis. These informative markers targeting (GATA) n motifs representing a new set of markers in rice will be highly useful for genetic studies and marker-assisted selection. [ABSTRACT FROM AUTHOR]