【摘要】 为了探明γ-氨基丁酸(GABA)对糯玉米产量形成影响及其光合生理,指导糯玉米产量提高的化控技术应用。以糯玉米品种粤彩糯2号(V1)、京科糯928(V2)和粤白甜糯7号(V3)为材料,以根灌清水(CK)为对照,研究了孕穗期根施GABA处理(RS)对糯玉米产量和光合生理的影响。与CK相比,RS处理提高了供试糯玉米品种的净穗产量(1.62%～4.97%),降低了供试糯玉米品种的苞叶产量(16.52%～23.09%),其中粤白甜糯7号的净穗产量提高和苞叶产量减低均达显著水平。RS一定程度提高了灌浆期和成熟期的净光合速率和蒸腾速率,提高成熟期叶片老化指数;提高穗长、行粒数、总粒数;促使抽穗期、散粉期和叶丝期提前了1～2 d。RS处理显著提高了成熟期功能叶CAT活性,显著降低了功能叶的MDA含量。净穗产量与鲜苞产量、鲜苞穗叶比、穗长、穗行数、总粒数和灌浆期叶片老化指数呈显著正相关关系(P<0.05)。孕穗期根施GABA处理可以通过调控糯玉米品种的光合生理、产量构成因子和鲜苞的苞叶占比等影响糯玉米品种的净穗产量提高。更多还原

【Abstract】 The aim of this work was to evaluate the effects of γ-aminobutyric acid(GABA)on waxy maize yield formation and its photosynthetic physiology, for guide the application of chemical control technology to improve the yield of waxy corn.The waxy maize varieties Yuecainuo 2,Yuebaitiannuo 7,and Jingkenuo 928 were used as materials, the effects of root application of GABA treatment(RS)on yield and photosynthetic physiology of waxy maize were studied, the root irrigation of water was taken as control(CK).Compared with CK,RS treatment increased naked ear yield of waxy maize varieties(1.62%-4.97%),the bract leaves yield of waxy maize varieties was reduced(16.52%-23.09%),among them, the naked ear yield and the bract leaves yield of Yuebaitiannuo 7 changed significantly. RS treatment improved the net photosynthetic rate and transpiration rate at both filling stage and mature stage, improved the leaf aging index at mature stage. The spike length, number of grains per row, and number of grains per spike were increased to some extent.The heading stage, powder period, and the spinning stage were advanced 1-2 d.The CAT activity in functional leaves was significantly improved under RS treatment but the MDA content in in functional leaves was significantly decreased under RS treatment. A significant positive correlation was observed between naked ear yield and fresh bracts yield, ratio of fresh bracts to ears and leaves, spike length, number of grains per row, number of grains per spike, and leaf aging index at filling stage(P<0.05).Root application of GABA treatment during booting stage can improve the naked ear yield of waxy maize varieties by regulating growth, photosynthetic physiology, yield formation, and the ratio of fresh bracts to ears and leaves.更多还原