不同土壤水分条件下施磷量对小麦旗叶衰老及产量的影响

在防雨旱棚池栽条件下研究了水分胁迫(W1)和水分适宜(W2)条件下不同施磷量对小麦旗叶衰老及产量的影响.结果表明,小麦开花后,W1水平下,施磷150 kg/hm~2处理的超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)下降幅度及丙二醛(MDA)上升幅度较其他处理小;W2水平下,随施磷量的增加,SOD、POD和CAT活性增加、MDA降低,可见水分胁迫下适宜的施磷量以及适宜的水分条件下增加施磷量均可以改善小麦体内的保护酶,增加小麦叶面积指数和旗叶叶绿素含量,提高光合速率,进而延缓衰老,提高产量.本试验条件下,虽然75%土壤田间持水量与施磷量150 kg/hm~2的处理组合达到了最高产量,但与55%土壤田间持水量与施磷量150 kg/hm~2的处理组合的产量差异不显著,综合观之,后者是最佳水肥处理组合.

Effects of different soil water conditions and different phosphorus supplied on the flag leaf senescence and yield of wheat

In order to clarify the rational regulation of different water conditions and phosphorus supplied,a rain-proof pool culture experiment,including two water levels,I.e.,moderate soil water content(75%),water stress(55%),and three fertilizing levels,I.e.,P1(75 kg/hm~2),P2(150 kg/hm~2),P3(225 kg/hm~2)was conducted.The results showed that the decreasing range of SOD、POD、CAT and arising range of MDA in P2 treament under W1 were lower than the other two after anthesis.The activities of SOD、POD、CAT increased and the content of MDA decreased with the increase of phosphorus.Therefore moderate phosphorus supplied under W1 and increasing phosphorus supplied under W2 could improve protective enzyme,increase leaf area index、chlorophyll content,and photosynthetic rate,delay the senescence,incease the yield.Though W2P2 achieved the highest yield,compared with W1P2,it had no siganificant difference.It was concluded that the treatment W1P2 was the better combination of water and fertilizer.