The role of exogenous individual or combined application of silicon (Si) and salicylic acid (SA) (control, 6 mm Si, 1 mm SA, and 6 mm Si + 1 mm SA) on grain yield and some key physiological characteristics of wheat (Triticum aestivum L.) cvv. Shiraz (drought-sensitive) and Sirvan (drought-tolerant) was investigated under field water-stress conditions (100% and 40% field capacity). Drought stress caused a considerable reduction in biological yield, yield and yield components, relative water content and leaf water potential of both cultivars. Application of Si and SA effectively improved these parameters in water-deficit treatments. Moreover, water-limited conditions markedly promoted the activities of key antioxidant enzymes including peroxidase, ascorbate peroxidase, catalase and superoxide dismutase as well as the levels of malondialdehyde (MDA) and hydrogen peroxide (H2O2), while enhancing the accumulation of soluble sugars, potassium, magnesium and calcium in leaf tissues. Application of Si and SA further enhanced the activities of the key antioxidant enzymes and accumulation of osmolytes, and decreased the levels of H2O2 and MDA in drought-stressed plants; the positive effects of Si were greatest when it was applied with SA. Synergistic effects of Si + SA application on yield and physiological parameters were apparent compared with Si or SA applied separately. Water-stress alleviation and yield improvement in the wheat cultivars by Si and SA application was attributable to partly improved osmotic adjustment and antioxidant activity as well as to more favourable water status under stress conditions. Overall, Si and SA application proved to have great potential in promoting grain yield of wheat in drought-prone areas.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 70 • No. 1