Evaluation of water deficiency impacts on antioxidant enzymes activity and lipid peroxidation in some tomato (Solanum lycopersicum L.) Lines

This experiment was conducted to evaluate the effects of drought stress on some quality traits of tomato, seven tomato lines were assessed in an experimental field at Ilam University in 2016. The layout was split plots according to randomized complete block design (RCBD) with 3 levels of drought stress including 100, 60% and 40% of field capacity with 3 replications. The genotypes were including King stone, Peto early, Bitstoik, LA1607, LA2656, LA2080 and LA1579. The effect of mild and severe drought stress on the activity of antioxidant enzymes, including peroxidase, catalase and ascorbate peroxidase were investigated. The statistical analysis showed that drought stress significantly affected all assessed traits under drought condition. CAT, chlorophyll content and RWC were reduced, but, APX, POX, Proline and MAD content as well as electrolyte leakage increased and the highest content was observed under severe drought stress (40%FC). The genotypes LA1607, LA2656, LA2080 and LA1579 identified as the most tolerant and King Stone, Peto early and Bitstoik were the most susceptible genotypes. Under severe drought stress, the highest RWC in LA2080, POX in LA1579, APX in LA1607, Chlorophyll a in LA2080, Chlorophyll b in Peto early, Chlorophyll T in Bitstoik and LA2080, EL in LA2080, MDA in Bitstoik and prolin in Petoearly were observed.