Physiological and biochemical changes in wheat cultivars under salt stress as affected by foliar boron application

Abstract

In this study, interactive effects of salt stress (150 mM NaCl) and foliar boron (H3BO3; 30 µM) application was studied in two wheat (Triticum aestivum L.) genotypes (Momtchil and Pamukova-97). Chlorophyll a and total chlorophyll content in Momtchil were not affected by salinity, foliar boron and salinity+foliar boron application while chlorophyll b content was increased by foliar boron and salinity+foliar boron application as compared to relative controls, probably due to higher total carotenoid and free proline level. In Pamukova-97, however, foliar boron and salinity+foliar boron application led to the reduced photosynthetic pigment content because of the absence of such a protective mechanism. Antioxidant enzymes of ascorbate-glutathione cycle and superoxide dismutase was not induced by all applications and both remarkable H2O2 accumulation and membrane damage was determined in the leaves of wheat cultivars, as demonstrated by higher MDA content in leaves. As a result, it may be concluded that expected ameliorative effect of foliar boron application did not occur in salt-affected wheat cultivars used in this study.