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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]

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]