Effect of water control in combination of depth and amount on dry matter partition and water use efficiency of winter wheat

A three years field tria1．under the water control experim ent with different soll depths and water contents，is cartled out to study the effects of water control on dry matter distribution， yield and water use efficiencies of winter wheat．The resUIts show that the dry matter accum ulation above the ground is 65％ FC> 50％ FC> 80％ FC in the treatment of surface irrigation and 80％ FC>65％ FC>50％FC in other three treatments of under surface irigation；the treatment of 30cm×80％ FC produces the highest yield of 6512．4kg／hm², the lowest yield of 3568．1 kg／hm² appears in the treatment of 50cm ×50％ FC．The crop water use efficiency gradually increases with the depths increasing．The optimum combinations would be 30cm × 80％ FC and 30cm × 65％ FC．