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生长在旱地条件下的小麦在籽粒灌浆期间．环境胁迫可加大其对贮藏同化物的依赖性．本研究之目的是确定开花后遮荫小麦叶片与茎秆中非结构性碳水化合物的损失量（ＴＮＣ）和籽粒于物质增加量。１９９１—１９９２年．在德克萨斯州的Ｔｅｍｐｌｅ于田间条件下．用Ｍｉｔ小麦品种在花后１０—１１ｄ开始实施遮荫处理。遮荫期间．带穗植株的茎干物质减少量１９９１年为２９０ｇ／ｋｇ．１９９２年为１４０ｇ／ｋｓ。叶干物质减少量１９９１年为２４０ｇ／ｋｇ．而１９９２年增加了１０ｇ／ｋｇ。茎叶贮藏碳水化合物减少量最大的为果糖和庶糖．而淀粉并不因遮荫而发生再流动。估计的维持系数１９９１年为４．３ｍｇ碳水化合物／克于物质·天．１９９２年为１．８ｍｇ碳水化合物／克干物质·天．１９９１年遮荫初始阶段维持呼吸消耗占ＴＮＣ的６８％．１９９２年占１８％．从叶、茎及穗部非籽粒组织流失的每克同化物所生产的籽粒量１９９１年为０．６８ｇ．１９９２年为０．７８ｇ．除去维持呼吸的部分后．每克流失的同化物产生的籽粒量估计为０．８２ｇ和０．９３ｇ。由此可见．当在籽粒灌浆期间发生胁迫时．贮藏碳水化合物对籽粒形成起着重要的缓冲作用。
Wheat grown under dry conditions during grain filling. Environmental stress can increase its dependence on storage assimilates. The purpose of this study was to determine the loss of non-structural carbohydrates (TNC) and the increase in grain content of shady wheat leaves and stems after flowering. 1991-1992. Temple in Texas under field conditions. With the wheat varieties of wheat 10-11d after flowering began to implement shading treatment. Shade period. The reduction of stem material of spike plants in 1991 was 290 g / kg. 1992 was 140g / ks. Leaf dry matter reduction in 1991 was 240g / kg. While in 1992 an increase of 10g / kg. The largest reduction of stored carbohydrate in stems and leaves was fructose and sucrose. Starch does not re-flow because of shade. The estimated maintenance factor was 4.3 mg carbohydrates per gram of substance in 1991. 1.8 mg carbohydrates / gram of dry matter per day in 1992. In 1991, the initial stage of shade maintenance of respiratory consumption accounted for 68% of TNC. In 1992, 18%. The amount of grain produced per gram of assimilate lost from leaves, stems and ears of non-seed tissue in 1991 was 0.68 g. In 1992 it was 0.78g. After removing the part that maintains breathing. The amount of grain produced per gram of lost assimilate was estimated to be 0.82 g and 0.93 g. This shows. When stress occurs during grain filling. Storage of carbohydrates plays an important buffering role in grain formation.