Effect of Hydrogen Peroxide Application on Salt Stress Mitigation in Bell Pepper (Capsicum annuum L.)

The present study aimed to evaluate the effects of the foliar application of hydrogen peroxide on the attenuation of salt stress on the growth, photochemical efficiency, production and water use efficiency of 'All Big' bell pepper plants. The experiment was conducted under greenhouse conditions in Campina Grande, PB, Brazil. Treatments were distributed in a randomized block design, in a 5 x 5 factorial scheme, corresponding to five levels of electrical conductivity of irrigation water (0.8, 1.2, 2.0, 2.6 and 3.2 dS m(-1)) and five concentrations of hydrogen peroxide (0, 15, 30, 45 and 60 mu M), with three replicates. Foliar application of hydrogen peroxide at concentration of 15 mu M attenuated the deleterious effects of salt stress on photochemical efficiency, biomass accumulation and production components of bell pepper plants irrigated using water with an electrical conductivity of up to 3.2 dS m(-1). Foliar spraying of hydrogen peroxide at a concentration of 60 mu M intensified the effects of salt stress. The 'All Big' bell pepper was classified as moderately sensitive to salt stress, with an irrigation water salinity threshold of 1.43 dS m(-1) and a unit decrease of 8.25% above this salinity level.

Automated summary

The study evaluated the effects of foliar application of hydrogen peroxide on salt stress in bell pepper plants. It was found that a concentration of 15 μM attenuated the negative effects of salt stress on plant growth and production components, while a concentration of 60 μM intensified the stress. The threshold for irrigation water salinity in 'All Big' bell pepper plants was determined to be 1.43 dS m(-1), above which there was a decrease in yield.