Mitigating water stress on wheat through foliar application of silicon

Climate change emerges in different forms such as drought, which is prevalent all over the world, especially in semi-arid and arid regions. Crop production especially wheat (Triticum aestivum L.) yield is affected due to water shortage at critical growth stages in Pakistan. A greenhouse experiment was conducted by using plastic trays to assess the performance of wheat to exogenous silicon (Si) application under water stress which in applied through skipping irrigation at critical stages at College of Agriculture, University of Sargodha, Pakistan. Experiment include irrigation levels (I1: irrigation at crown root stage + booting stage, I2: irrigation at crown root stage + anthesis stage, I3: crown root stage + grain development stage, I4: crown root stage + booting stage + anthesis stage + grain development stage, I5: crown root stage + tillering stage + booting stage + earing stage + milking stage + dough stage) and foliar application of Si viz., Si0: 0% (Control), Si1: 0.25%, Si2: 0.50%, and Si3: 1% (w/v). Treatment combination I1 + Si0 significantly reduced yield and yield attributes, net assimilation rate, Si contents in plants, leaf water potential, chlorophyll content, root length and water use efficiency furthermore, increased evapotranspiration efficiency. In contrast, treatment combination I5 + Si3 significantly increased these parameters and reduced evapotranspiration efficiency. Moreover, treatment combinations I4 + Si3 and I3 + Si3 were statistically at par with treatment combination I5 + Si3 which indicating the role of Si in mitigating negative impact of water shortage and improved these parameters. It is concluded that plant exhibited positive response at irrigation levels I3 and I4 in combination with foliar-applied Si3 while irrigation level lower than I3 with Si3 was not showed positive improvement in crop productivity.