为探讨信号分子过氧化氢(H 2 O 2 )对干旱胁迫下裸燕麦生理响应的调控机制,以砂培白燕7号幼苗为材料,研究了喷施0.01 mmol·L -1 H 2 O 2 对17.8%聚乙二醇6000模拟的干旱胁迫下叶片光合特性、活性氧代谢、渗透调节物质积累和幼苗生...为探讨信号分子过氧化氢(H 2 O 2 )对干旱胁迫下裸燕麦生理响应的调控机制,以砂培白燕7号幼苗为材料,研究了喷施0.01 mmol·L -1 H 2 O 2 对17.8%聚乙二醇6000模拟的干旱胁迫下叶片光合特性、活性氧代谢、渗透调节物质积累和幼苗生长的影响。结果表明:喷施H 2 O 2 后,干旱胁迫下的裸燕麦幼苗叶片叶绿素a、叶绿素b、总叶绿素、类胡萝卜素含量和叶绿素a/b较对照(喷H 2 O后干旱胁迫)分别提高了20.0%、12.9%、18.5%、8.1%和24.3%,叶片净光合速率、气孔导度、胞间CO 2 浓度和水分利用效率分别提高了20.6%、25.9%、12.0%和33.8%,蒸腾速率降低了9.7%;喷施H 2 O 2 还使干旱胁迫下裸燕麦幼苗叶片的过氧化氢酶、抗坏血酸过氧化物酶活性和抗坏血酸含量分别提高了113.5%、102.9%和13.8%,而超氧化物歧化酶、过氧化物酶活性及O —· 2 、H 2 O 2 、丙二醛含量和细胞膜相对透性分别下降了21.5%、60.4%、29.3%、38.4%、19.7%和14.2%,可溶性蛋白质、可溶性糖、游离氨基酸和脯氨酸含量分别上升了10.5%、40.3%、13.8%和17.2%,幼苗株高、根长、植株鲜重、植株干重和相对含水量分别提高了14.8%、25.0%、20.1%、11.0%和5.93 %,但谷胱甘肽含量没有显著变化。表明外源H 2 O 2 能够通过降低膜脂过氧化程度和促进渗透溶质积累,改善叶片光合功能和植株水分状况,从而减轻干旱对裸燕麦幼苗生长的抑制,增强裸燕麦的抗旱性。展开更多
Peeled naked oat kernels, named “oat rice” (OR) by Chinese food scientists and processors, are novel oat products in China. This study exam-ined the effects of steaming and roasting treat-ments on the enzyme activit...Peeled naked oat kernels, named “oat rice” (OR) by Chinese food scientists and processors, are novel oat products in China. This study exam-ined the effects of steaming and roasting treat-ments on the enzyme activities, nutritional con-tents, and flour pasting properties of OR kernels. Results showed that a peeling time of 20 s caused 16.13% β-glucan loss, while a peeling time 25 s caused 34.29% β-glucan loss in the kernels. OR kernels with a 20 s peeling treatment demonstrated significantly higher starch levels and kernel whiteness compared with normal oat kernels (P<0.01). It was also found that normal pressure steaming, autoclaved steaming and infrared roasting treatments could exterminate lipase activities in the OR kernels, and provide the OR kernels with significantly lower final viscosities and setback values than normal kernels (P<0.01).展开更多
文摘Peeled naked oat kernels, named “oat rice” (OR) by Chinese food scientists and processors, are novel oat products in China. This study exam-ined the effects of steaming and roasting treat-ments on the enzyme activities, nutritional con-tents, and flour pasting properties of OR kernels. Results showed that a peeling time of 20 s caused 16.13% β-glucan loss, while a peeling time 25 s caused 34.29% β-glucan loss in the kernels. OR kernels with a 20 s peeling treatment demonstrated significantly higher starch levels and kernel whiteness compared with normal oat kernels (P<0.01). It was also found that normal pressure steaming, autoclaved steaming and infrared roasting treatments could exterminate lipase activities in the OR kernels, and provide the OR kernels with significantly lower final viscosities and setback values than normal kernels (P<0.01).
