土壤水胁迫对冬小麦生长发育、干物质积累与分配的影响

Effect of Soil Water Stress on Growth,DM Accumulation and Distribution of Winter Wheat

采用盆栽方法,在控制越冬至成熟期间土壤水及力对冬小麦(许06)影响的条件下,研究了土壤水协迫对冬小麦的影响,结果表明:在0.3bar水吸力条件下,小麦体内保持良好的水分状态和根系活力,生长发育健壮,体内同化物积累多,花后灌浆期光合产物占总积累的35%,占籽粒产量的91.1%,小麦表现为穗多、粒多、粒重、产量高。随着土壤水吸力的提高,小麦体内水分胁迫增强,生育受抑制的程度加重,地上部受胁迫的影响较地下部为重,干物质积累减少,籽粒物质来自于贮藏同化物的比例上升。0.5bar 处理小麦拔节受抑,株高降低,分蘖成穗数显著减少,但穗粒数、千粒重与0.3bar 处理差异不大,小麦产量下降25.1%。1.0bar 处理小麦,产量三因子大幅度下降。≥3.0bars,小麦近于绝收,体内干物质积累很少,灌浆期不但无净光合积累,反而有较多损失。另外在0.3～1.0bar 范围内,随着土壤水吸力的提高,小麦生育进程加快,成熟提前,但≥3.0bars,小麦两极分化滞缓,生殖生长受阻,不能正常成熟。池栽试验的结果与盆栽基本一致,0.3bar 处理下,小麦产量最高。但在同等水吸力下,池栽小麦受胁迫危害的程度要小于盆栽小麦。

In a pot trial,winter wheat CV.Xu 06 was subjected to 5 levels.of soil water suction(SWS)applied from early overwintering to maturityThe result showed:Treated with 0.3 bar SWS,the plant grew vigorously,moreears,more grains,and higher 1000-grain weight and yield.As SWS increasedthe enhenced water stress obstructed the growth of wheat,DM accumulatedreduced and the ratio of the portion coming from stored assimilation incre-ased.With SWS of 0.5 bar,the plant shortened,ear numbers reduced sign-ificantly and the yield suffered a decrease of 25.1% compared with that at0.3 bar.SWS at 1.0 bar,all the three yield components lessened to a bigmargin.SWS(?)3.0 bars,wheat plant accumulated very little amount of DMand nearly no grain was harvested.In addition,SWS increased from 0.3 to1.0 bar,the wheat ripened earlier.