断根对冬小麦荧光特性和产量的影响

Effects of Root Excision on Fluorescent Properties and Yield of Winter Wheat

用荧光淬灭分析技术研究了断根对冬小麦荧光特性的影响以及不同水分条件下断根对产量的影响.结果表明,在不同生育期中小麦断根与未断根处理相比其最大量子产量(Fv/Fo)和PSⅡ潜在活性(Fv/Fm)无显著差异.通过对不同生育期荧光特性研究表明,断根初期小麦电子传递速率和有效光量子产量降低,而PSⅡ光合电子传递活性增加,孕穗期随着更多的能量向地上部的运转,此时根系补偿作用使ETR、ΦPSⅡ和qP增加,而且断根并显著降低光系统Ⅱ光化学效率.混播处理ΦPSⅡ和ETR值高于单播处理,认为断根降低了小麦的竞争能力,使总体光合活性增强,促进了能量向地上部运转,与混播处理产量增加相一致.小麦单播湿润处理下,断根降低了小麦穗重和地上部生物量,且籽粒产量降低了19.2%.在干旱处理下,断根降低了根冠比,提高了小麦穗重和籽粒产量.

Fluorescence quenching was ties as well as on the yield of winter adopted to probe the effects of wheat under different moisture root excision on fluorescent propercircumstances. The results indicated that at different growth stages,maximum quantum yield （Fv/Fo） and potential PS Ⅱ activity （Fv/Fm） of wheat in the treatment with root excision did not significantly differ from those in the treatment without root excision. The fluorescence properties at different growth stages showed that root excision initially made the ETR and ФPS; of wheat decline but the photosynthetic electron transport of wheat PSⅡ increase in its activity. In the booting stage, because more energy was transported to the aboveground parts, root compensation made the ETR,Фps; and qP increase ,and that root excision did not significantly reduced the photochemical efficiency of PS Ⅱ . The ФPS; and ETR under the mixed planting mode were higher than those under the single planting mode and this was thought of resulting from that root excision reduced the competitive edge of wheat but increased the whole photosynthetic capacity thereby helping transport energy to the aboveground parts and consisting with the yield increase under the mixed planting mode. In normal moisture treatment under the si ground biomass of wheat as well as ngle planting mode,root excision reduced the spike weight and abovethe kernel yield by 19.20%. In drought treatment ,root excision lowered the root/shoot ratio of wheat and raised the spike weight and kernel yield of wheat.