Dynamics of Structural Dry Matter, Water Soluble Carbohydrates and Leaf Senescence Mediate the Response of Winter Wheat Yield to Soil Cover and Water Availability

Plastic film mulching often increases the yield of winter wheat in Loess Plateau China, but physiological mechanisms are unclear, especially response to interaction between mulch and water supply. In this study, we investigated interactive effects initial soil (dry, moderate, wet), cover (plastic mulch, bare soil), seasonal conditions on dynamics dry matter partitioning, water-soluble carbohydrates (WSC), flag leaf senescence, their relations with its components. increased accumulation at anthesis maturity relative soil, no season or water. Allocation leaf, stem, spike did not change cover. Compared WSC by 14% translocation 16%. Soil influence senescence after as indicated similar C:N ratio. Grain was higher under plastic than two out three seasons, associated a amount post-anthesis that linked grain weight, number, harvest index.