BIOCHEMICAL RESPONSES OF COMMON BEAN (PHASEOLUS VULGARIS L.) GENOTYPES TO WATER STRESS UNDER MID HILL CONDITIONS
Usha Rana* and Meena Kumari
Department of Biology & Environmental Sciences, College of Basic Sciences, CSKHPKV,Palampur–1760624-230311
[Corresponding author E-mail*: email@example.com]
Received: 31-08-2015 Accepted: 06-10-2015
Experiment was conducted to assess drought-tolerance in seven common bean genotypes by inducing stress at flower initiation stage on the basis of inherent stress tolerance characters viz.total chlorophyll content, chlorophyll stability index, nitrate reductase activity, total free proline content, total free amino acids and drought susceptibility index. Data of various biochemical parameters was recorded and revealed significant differences among the various common bean genotypes for chlorophyll content and proline accumulation. KR 15 and KR 186-I, showed minimum reduction in chlorophyll content, chlorophyll stability index and nitrate reductase activity and maximum decline in these parameters was observed in KR 84 and KR 257. Total free proline content and total free amino acids were minimum in the genotypes KR 15 and KR 186-I, whereas, KR 84 and KR 257 showed marked increase. KR 186-I, KR 15 and KRC 5 were found to be most drought tolerant genotypes with lower drought susceptibility index, while KR 257 and KR 84 were most drought susceptible genotypes with higher drought susceptibility index. It was concluded that genotypes KR 186-I, KR 15 and KRC 5 proved to be tolerant to water stress and genotypes KR 60 and KR 142 were moderately drought sensitive, whereas genotypes KR 84 and KR 257 were highly susceptible to water stress.
Keywords: Common bean, Drought tolerance, susceptibility index, water stress