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Background: Blackgram is one of the important pulse crops belongs to the Papilionaceae family. Seed germination and seedling growth are a very important step in the survival of a plant. Water stress is one of the important factors affects seedling growth. Methods: An experiment was conducted to study the effect of water stress on seedling growth in twenty-one blackgram [Vigna mungo (L.) Hepper] genotypes at the pot culture yard of Annamalai University during March 2018. The water stress was created by using Polyethylene Glycol (6000 MW) in different concentrations (0%, 10% and 20%). Different phenotypic characters were recorded such as shoot length, root length, shoot fresh weight, root fresh weight, shoot dry weight and root dry weight at two different levels of treatment and control. The experiment was laid in a completely randomized design with two replications. Result: The combined analysis of variance revealed significant differences (p less than 0.001) among genotypes, treatments and genotypes × treatments interaction. The highest stress tolerance index (STI) was recorded by the genotype ADT-5. Based on clustering and ranking, the genotypes ADT-5, KGB-28, RU-16-9, VBG-10010 and VBG-12062 were classified as drought-tolerant. Overall, pot culture screening of 21 blackgram genotypes for drought tolerance at seedling stage using various concentrations of PEG 6000 resulted in the identification of drought-tolerant genotypes, where ADT-5 showed the highest tolerance followed by KGB-28 and RU-16-9.

: Combining ability analysis was studied in a line x tester analysis of rice (Oryza sativa L.). The analysis of variance for combining ability revealed that the variance due to GCA and SCA were highly significant for all the characters indicated that nonadditive gene actions were involved in the expression of the traits. Among the line AURC 14 and testers IR 64 and ADT 43 were considered as the best general combiners, while hybrids AURC 1 x ADT 36, AURC 8 x ADT 36, AURC 8 ADT 43, AURC 10 x ADT 43, AURC 14 x ADT 36, AURC 14 x TRY 1, AURC 22 x IR 64, AURC 22 x TRY 1 and AURC 25 x ADT 36 as good specific combiners for grain yield and other yield contributing and quality traits. The promising line AURC 14 and testers IR 64 and ADT 43 which are having high GCA effects in desirable direction for yield components and for quality traits may be incorporated in crossing programme. The crosses AURC 14 x TRY 1 and AURC 22 x IR 64 exhibited good SCA effects for major yield and more than seven yield contributing characters. This may be exploited for better yield and quality either by exploiting them through heterosis breeding or involving them in multiple cross breeding programme.