不同时期喷施草甘膦对大豆生理指标的影响

 采用随机区组的设计方法，分别在第一、二、三复叶期喷施不同剂量的41%草甘膦异丙胺盐水剂，研究了其对抗草甘膦大豆RR2和普通大豆晋大75叶片叶绿素含量指数、莽草酸质量分数和SOD活性等生理指标的影响。结果表明：在不同时期喷施w为41%草甘膦异丙胺盐水剂均可以抑制RR2和晋大75的叶绿素合成，促进大豆体内莽草酸的积累，但RR2对w为41%草甘膦异丙胺盐水剂的抗性远高于晋大75。施药时期越早，大豆的叶绿素含量指数越低，晋大75叶片的莽草酸质量分数越低。不同时期施药对RR2和晋大75的SOD活性均影响不大。3次施药以第三复叶期对晋大75的伤害最大。所测3个生理指标的敏感性依次为叶片莽草酸含量>叶绿素含量指数> SOD活性。比较不同时期喷施w为41%草甘膦异丙胺盐水剂对大豆生理指标的变化，从一定意义上对于了解转基因大豆和常规大豆对草甘膦的耐药性差异及其他生理响应机制有重要参考价值，为大豆田合理运用草甘膦提供依据。

Impact of Spraying Glyphosate on Physiologi Physiological Index of Soybean at Different Growth Stages

Random complete block design was used to research the impact of spraying 41% Glyphosate-isopropylammonium AS on physiological indexes of glyphosate-resistant soybean cultivars (RR2) and ordinary soybean cultivars (Jinda75) at different growth stages, one-trifoliolate, two-trifoliolate and three-trifoliolate leaf stage. The chlorophyll content index, shikimic acid content and SOD activity were measured. The results indicated that, the chlorophyll content indexes of RR2 and Jinda75 decreased with increasing the dosage of herbicide, while shikimic acid contents increased. The earlier 41% Glyphosate-isopropylammonium AS was applied, the less the chlorophyll content index was; But the shikimic acid content of ordinary soybean was opposite. The impact of 41% Glyphosate-isopropylammonium AS on SOD activity of the soybean was little. The injury of 41% Glyphosate isopropylammonium AS on ordinary soybean at three-trifoliolate leaf stage was the largest. During these three physiological indexes, shikimic acid content was the most sensitive, and SOD activity was the last. The change of physiological indexes could show the glyphosate-resistance differences of cultivars and had an important significance for applying glyphosate appropriately in soybean field.