Antioxidant, lipid peroxidation and cell membrane stability influence yield in Cucumis sativus L. by chitosan application under different sowing times

Abstract

Heat stress in a major obstacle in cucumber
production in the Punjab province of Pakistan. To save
cucumber production from heat stress, a study was
designed to evaluate chitosan on cucumber genotypes for
yield enhancement under three sowing dates. Four
cucumber genotypes, two tolerant (L3466 and Desicucumber) and two susceptible (Suyo Long and Poinsett),
were screened in a previous experiment under field
conditions during 2016. The 1st sowing date was 15th
March, followed by 1st April, and 15th April, respectively
with four replications. Chitosan level (200 ppm) was
applied as foliar spray at 30 days post-sow and then
applied two times after a week interval. During present
research, the highest summer temperature was 47.5 °C recorded in May, 48°C in June, and 46.1°C in July. Chitosan
improved the enzymatic antioxidants and osmolytes in
enhancing the ability of cucumber to tolerate heat stress.
Enhancement in biochemical characteristics (Superoxide
dismutase, peroxidase, catalase, and protein content) were
observed in chitosan treated plants as compared with nontreated plants. It was revealed that yield per plant was highest
in L3466 (2.12 kg) and Desi-cucumber (2.10 kg) with chitosan
application on the 1st sowing date, while yield per plant was
reduced in Suyo Long (0.31 kg) and Poinsett (0.29 kg) on the
third sowing date with chitosan application. However, in 3rd
sowing date Suyo Long and Poinsett could not survive at the
fruiting stage without the chitosan application. L3466 and
Desi-cucumber could be a benefit to farmers with chitosan
application and breeders for further studies for heat stress
tolerance. © 2020 Department of Agricultural Sciences, AIOU