草甘膦对耐草甘膦大豆体内莽草酸含量及产量的影响

Shikimic Acid Accumulation as an Indicator of Glyphosate Tolerance in Glyphosate- Resistant Soybean

采用网室盆栽试验与田间试验相结合的方法，测定处于不同叶龄的大豆在草甘膦处理后莽草酸的积累量。结果表明：1230～2460 g a．i．/hm2草甘膦处理后，常规大豆莽草酸积累量急剧上升，并随草甘膦处理剂量的增加而升高。耐草甘膦大豆莽草酸积累量与不用药的空白对照差异不显著；在4920 g a．i．/hm2草甘膦处理后，体内莽草酸出现短时间的积累，但5～9d后恢复至药前水平。在3、5、7张羽状三出复叶期喷施草甘膦后，不同叶龄之间的大豆叶片莽草酸积累量差异不显著，说明这3个叶龄处理的耐草甘膦大豆均有较好的耐受性。上述草甘膦处理剂量及处理时期施药后，耐草甘膦大豆籽粒产量与不用药的空白对照差异不显著。

Pot experiments and field trials were conducted to determine the shikimate accumulation after glyphosate appli -cation during the period of soybean growth .At 1 230.0~2 460.0 g a.i./hm2,shikimate accumulation rapidly increased in leaves of conventional soybean .Accumulation increased with increasing herbicide doses .Shikimate accumulation in glyphosate-resistant soybean did not differ between glyphosate -applied and blank control treatments .Shikimate accu-mulation did not differ among glyphosate -resistant crop plants treated with glyphostate at the 3 -,5 -and 7 -leaf growth stages,which indicates that transgenic soybeans at those growth stages expressed high tolerance to glyphosate .At 4 920 g a.i./hm2 ,shikimate transiently accumulated but returned to its normal level before the glyphosate application after 5~9 days.The transgenic glyphosate -resistant soybean subjected to the above dosage of glyphosate produced the same yield as the blank control .Shikimate accumulation can be used as an early detection index of glyphosate tolerance levels of soybean .