【作者】 解备涛；

【导师】 李建民；

【作者基本信息】 中国农业大学 ， 作物栽培与耕作学， 2003， 硕士

【摘要】 以冬小麦农大189和中优9507为试验材料，在灌浆期处在高温(45℃)和紫外辐射(波峰为253nm，30w)两种逆境条件下，研究了植物生长物质γ-氨基丁酸(GABA)和表油菜素酯(BR)在开花期喷施处理对小麦产量、品质及相关生理过程的影响，主要结果如下： 1．本实验条件下，高温和紫外辐射两种逆境均导致小麦产量显著下降，植物生长物质对这种产量的下降表现一定的减缓作用。BR处理提高了高温胁迫下两小麦品种的产量，GABA处理提高高温胁迫中优9507和紫外辐射逆境下农大189的产量。 2．高温胁迫对小麦品质有不良影响，如两品种干、湿面筋含量显著下降，中优9507的粗蛋白含量、沉降值也显著下降。BR处理能提高两品种的干、湿面筋含量，但粗蛋白含量、沉降值两品种表现不同。GABA处理提高两品种湿面筋含量，而降低沉降值和干面筋含量。紫外辐射提高了小麦子粒粗蛋白含量、沉降值等指标，在增加紫外辐射条件下，BR处理使干、湿面筋含量上升，两品种粗蛋白含量、沉降值表现有差异。GABA处理提高了中优9507粗蛋白含量、沉降值和干、湿面筋含量，农大189除沉降值和干面筋降低外，其他与中优9507效果相同。 3．GABA和BR影响高温和紫外辐射胁迫条件下对小麦叶片丙二醛(MDA)、超氧物歧化酶(SOD)活性和可溶性糖含量，且与其抗逆性变化相关。两种逆境条件都引起旗叶MDA含量上升，在高温和紫外辐射条件下，两种调节剂均使中优9507旗叶MDA含量下降，表明BR和GABA降低了两种逆境引起的膜脂过氧化程度。高温和紫外辐射均引起灌浆后期旗叶SOD活性降低，在高温条件下GABA处理提高了旗叶中SOD活性上升，与MDA含量降低一致。但在紫外辐射条件下，两种调节剂处理却都使SOD活性降低。但对可溶性糖含量的研究结果表明，高温引起小麦旗叶中的可溶性糖含量上升，而BR和GABA处理使之下降；紫外辐射胁迫使农大189旗叶中可溶性糖含量下降，BR和GABA均使之上升，植物生长物质处理可能通过改善渗透调节增强对膜的保护。 4．BR和GABA对小麦主要器官中激素含量的改变，可能是对高温胁迫和紫外辐射抗性增强的重要原因。如高温胁迫下，GABA和BR处理使小麦灌浆期旗叶IAA含量上升，后期ABA含量增加，有利于物质合成和输出；使籽粒中GA3含量提高，ABA峰值前移或升高，对加快灌浆和子粒发育有利。更多还原

【Abstract】 The effects of plant growth regulators(PGR) BR and GABA on the grain yield ,quality and physiological metabolism of winter wheat(triticum aestvum L) under the stress of ultraviolet radiation and high temperature in filling stage by using the cultivars NongDa 189 (ND189)and ZhongYou 9507 (ZY9507 ) as experiment materal treated at anthesis stage, and the main results were as following:1. In this experiment, high temperature and ultraviolet radiation decreased the grain yield of two cultivars significantly, and the treatments of PGRs showed alleviate effect on reduction of grain yield in two cultivars. The treatment of BR increased the grain yield of two cultivars under high temperature, and the treatment of GABA increased the grain yield of cv. ZY9507 under high temperature and of cv. ND189 under ultraviolet radiation.2. High temperature impacted the quality of wheat, For example, the gluten content of two cultivars and the total protein content and the sedimentation value of cv. ZY9507. decreased significantly under high temperature. BR increased the gluten content of two cultivars, however, it hardly changed the total protein content and the sedimentation value. GABA increased the wet gluten content but decreased the sedimentation value and dry gluten content of two cultivars. Ultraviolet radiation increased the total protein content and the sedimentation value. BR could increase the gluten content of two cultivars, and it had different effect on the total protein content and the sedimentation value in two cultivars. GABA increased the total protein content and the sedimentation value and gluten content in two cultivars except the sedimentation value and dry gluten content in cv. ND189.3. GABA and BR affected the MDA content, SOD activity and the soluble sugar content of flag leaf in two wheat cultivars under the stresses, which reflected the resistant ability. The MDA content of flag leaf in two cultivars rised under two stresses, but the PGRs decreased it, which showed that the PGRs decreased the degree of super oxidation in membrane. The both stresses decreased the SOD activity of flag leaf in the late stage of filling, GABA increased the activity under high temperature, which showed same effect of reduction in MDA content. The two treatments decreased the SOD activity in two cultivars, which showed adverse effect in high temperature. However, the result of sugar content showed that high temperature increased the content of soluble sugar, and GABA and BR decreased it. Ultraviolet radiation decreased the soluble sugar of flag leaf in cv. ND189, the both treatments increased it. which showed that the treatment of PGR might enhance the membrane by regulating the endosmosis4. BR and GABA may build up the resistant ability to high temperature and ultraviolet radiation by altering the level of phytohormone in tissue of wheat. For example, GABA and BR increased the IAA content in filling stage and the ABA content in the later, which could enhance the synthesis and export of assimilates, and the PGRs increased GA3 content and delayed or increased ABA content ,which benefit the development of grain.更多还原