Lack of suitable varieties and genotypes of black gram with adaptation to local conditions is among the factors affecting its production. Efforts to genetically improve the crop mostly involve identifying important morphological descriptors followed by development of advanced breeding lines for locale-specific cultivars. The present day available black gram varieties have not been properly characterized for their thermo sensitiveness with respect to morphological and biochemical characters. Hence efforts were taken in the present research to study the effect of the temperature on these characters in seven black gram varieties over different development stages. We aimed at studying the effect of 3 temperature regimes for identifying suitable stress tolerant genotypes. High percent germination (87.2%), root length (3.68？cm), carbohydrate content (3.72？mg？g？1 fresh tissue) among the genotypes was highest at 10°C–20°C temperature. High shoot length (13.39？cm), free amino acid content (3.73？mg？g？1 fresh tissue), and protein content (9.54？mg？g？1 fresh tissue) was found to be present when the genotypes were exposed to 20°C–30°C temperature. The black gram varieties J.L and PDU-1 performed best in all the temperature regimes over characters. Thus suitable varieties for all temperature regimes were identified using biochemical analysis. 1. Introduction Black gram (Vigna mungo) is a tropical leguminous plant, which belongs to the asiatic Vigna species along with V. radiata, V. trilobata, V. aconitifolia, and V. glaberecence. It has high nutritive value and consists of high content of proteins, vitamins, and minerals. ？V. mungo forms one of the important constituents in the dietary practices of the local communities. It is cultivated as fallow crop after rice cultivation in India. It is grown in various agroecological conditions and cropping systems with diverse agricultural practices. In recent years, there has been significant decline in its production in India. Lack of suitable varieties and genotypes with adaptation to local conditions is among the factors affecting its production. Efforts to genetically improve the crop are slow with only few efforts to identify important morphological descriptors and develop advanced breeding lines for locale-specific cultivars of this crop [1]. Stress is defined as an influence that is outside the normal range of homeostatic control in a given genotype [2]. Where a stress tolerance is exceeded, response mechanisms are activated, and where the stress is controlled, a new physiological state is established and homeostasis is
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