Journal of Plant Pathology & Microbiology

Evaluation of alterations in physio-biochemical attributes and antioxidant defense-system in heatstressed okra (Abelmoschus esculentus) cultivars and its putative use as heat tolerance idicators

International Conference on Plant Physiology & Pathology

June 09-10, 2016 Dallas, USA

Rashad M Balal

University of Sargodha, Pakistan

Posters & Accepted Abstracts: J Plant Pathol Microbiol

Abstract:

The current investigation was carried out to assess, whether the alterations in the activities of antioxidant enzymes and the levels of some non-enzymatic antioxidants, could be used as potential indicators of heat-tolerance in 10 commercialy important cultivars of okra (Abelmoschus esculentus L.). The tested cultivars were exposed to 3 different temperatures i.e., 25, 40 and 45°C under controlled conditions in growth chambers. Various growth, physiological and biochemcial characters in leaf or/and root tissues were analyzed. According to the percent inhibition in shoot/root, fresh and dry biomass at the highest temperature (45°C) cultivars Sabaz Pari, Desi Okra and Green Wonder were ranked as tolerant (percent inhibition less than 60%), Shahzadi, Anarkali, Sarsabaz and Rama Krishna moderately tolerant (percent inhibition 60�??70%), Click-5759 MF-03 and Pen Beauty are heat sensitive (percent inhibition more than 70%). Heat stress caused significant reductions in photosynthesis associated attributes but did not affect the number of stomata. High temperature-stress significantly elevated the activities of antixodiants, levels of osmolytes and decreased the MSI, and activities of GPX and CAT, while the internal levels of H2O2 remained unaffected in all tested okra cultivars. Although heat-induced oxidative stress was observed in all okra cultivars, but the response of heat-resistant and heat-sensitive cultivars with respect to the formation of enzymatic and non-enzymatic metabolites measured in the present study was not consistent. Of various gas exchange characteristics, antioxidant-enzymes and metabolites measured, only PN, MSI and activities of GPX and CAT activity was found to be a consistent indicators of heat-tolerance in tested okra cultivars.

Biography :

Email: rmb@uos.edu.pk