Morphological, biochemical and molecular insights on responses to heat stress in chilli Srivastava Arpita, Singh Khushboo, Khar Anil, Parihar Banna Ram, Tomar Bhoopal Singh, Mangal Manisha* Division of Vegetable Science, ICAR-Indian Agricultural Research Institute, New Delhi - 110012 *Corresponding author: manishamangal@rediffmail.com
Online Published on 02 May, 2022. Abstract Four heat susceptible and four heat tolerant genotypes of chilli were grown under high temperature as well as control conditions to study the morphological, biochemical and molecular changes occurring in them due to high temperature stress. It was observed that high temperature did not have significant effect on vegetative growth in chilli however the reproductive growth was significantly affected and was manifested as reduction in fruit length, fruit width, fruit weight and number of seeds per fruit. The detrimental effect was more pronounced in heat susceptible chilli genotypes. Tolerant genotypes accumulated more amounts of protein as well as proline and displayed higher activities of antioxidant enzymes like SOD (superoxide dismutase) and POD (peroxidase) in order to combat the high temperature stress. Out of seven Capsicum annuum specific heat shock proteins studied, three genes namely CaHSP 832 (HSP 83), Ca HSP 703(HSP70) and Ca HSP 2272 (small HSP) showed significant differences in expression level between tolerant and susceptible genotypes thereby suggesting their utility in discriminating the genotypes for their tolerance to heat stress. Top Keywords Capsicum annuum, High temperature tolerance, Heat shock proteins (HSP), Proline content, Antioxidant activity. Top |