遮荫对夏玉米产量和品质的影响

Effects of Shading on Yield and Quality of Summer Maize

研究在夏玉米不同生育时期遮荫对产量和品质的影响。结果表明:不同时期遮荫都显著降低玉米子粒产量,花粒期遮荫对玉米子粒产量影响最显著,农大108遮荫50%和90%的分别减产67.5%和79.4%,花粒期遮荫主要降低了千粒重;其次是穗期遮荫,农大108遮荫50%和90%的分别减产34.1%和55.3%,穗期遮荫主要减少了穗粒数;苗期遮荫对其影响相对较小,农大108遮荫50%减产16.9%。玉米子粒产量随着光照强度的减小而显著降低,不同时期遮荫对玉米子粒产量的影响显著大于不同遮荫程度(光照强度)的影响。苗期遮荫对玉米子粒品质没有显著影响;穗期和花粒期遮荫玉米子粒的粗蛋白和赖氨酸含量显著升高,粗脂肪、淀粉含量显著降低。随着光照强度的减小,对子粒品质的影响加剧。不同时期遮荫对玉米子粒品质的影响显著地大于不同遮荫程度的影响。

Shading decreased significantly grains yield of maize. Different shading phases had different effects on grains yield of maize. The effects of shading from flowering to maturity stage on grains yield of maize were most significant, then were from joining to flowering stage and from seedling to joining stag. Shading from joining to flowering stage decreased grains number mostly, and shading from flowering to maturity stage decreased 1 000-kernels weight mostly. Grains yield of maize was decreased significantly as the intensity of illumination decreased. Effects of different shading phases on grains yield of maize were significantly bigger than those of different intensities of illumination. Shading affected grains quality of maize significantly, and different shading phases had different effects on grains quality of maize. Shading from seedling to joining stage had no significant effects on grains quality of maize, while shading from joining to flowering stage and from flowering to maturity stage increased significantly crude protein and lysine contents, and decreased significantly ether extract and total starch contents. As the intensity of illumination decreased, the effects of it on grains quality were increased. Effects of different shading phases on grains quality of maize were significantly bigger than those of different intensities of illumination.