草甘膦对玉米中莽草酸、硝酸还原酶活性、产量和种子成分的影响。

Glyphosate effect on shikimate, nitrate reductase activity, yield, and seed composition in corn.

机构信息

Crop Production Systems Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Stoneville, Mississippi 38776, USA.

出版信息

J Agric Food Chem. 2010 Mar 24;58(6):3646-50. doi: 10.1021/jf904121y.

DOI:10.1021/jf904121y

PMID:20180575

Abstract

When glyphosate is applied to glyphosate-resistant (GR) crops, drift to nonglyphosate-resistant (non-GR) crops may cause significant injury and reduce yields. Tools are needed to quantify injury and predict crop losses. In this study, glyphosate drift was simulated by direct application at 12.5% of the recommended label rate to non-GR corn (Zea mays L.) at 3 or 6 weeks after planting (WAP) during two field seasons in the Mississippi delta region of the southeastern USA. Visual plant injury, shikimate accumulation, nitrate reductase activity, leaf nitrogen, yield, and seed composition were evaluated. Effects were also evaluated in GR corn and GR corn with stacked glufosinate-resistant gene at the recommended label rate at 3 and 6 WAP. Glyphosate at 105 g ae/ha was applied once at 3 or 6 weeks after planting to non-GR corn. Glyphosate at 840 (lower label limit) or 1260 (upper label limit) g ae/ha was applied twice at 3 and 6 WAP to transgenic corn. Glyphosate caused injury (45-55%) and increased shikimate levels (24-86%) in non-GR compared to nontreated corn. In non-GR corn, glyphosate drift did not affect starch content but increased seed protein 8-21% while reducing leaf nitrogen reductase activity 46-64%, leaf nitrogen 7-16%, grain yield 49-54%, and seed oil 18-23%. In GR and GR stacked with glufosinate-resistant corn, glyphosate applied at label rates did not affect corn yield, leaf and seed nitrogen, or seed composition (protein, oil, and starch content). Yet, nitrate reductase activity was reduced 5-19% with glyphosate at 840 + 840 g/ha rate and 8-42% with glyphosate at 1260 + 1260 g/ha rate in both GR and GR stacked corn. These results demonstrate the potential for severe yield loss in non-GR corn exposed to glyphosate drift.

摘要

当草甘膦施用于抗草甘膦（GR）作物时，漂移到非抗草甘膦（non-GR）作物可能会造成严重伤害并降低产量。需要工具来量化伤害并预测作物损失。在本研究中，在两个田间季节中，在美国东南部密西西比三角洲地区，在种植后 3 或 6 周（WAP）时，以推荐标签率的 12.5%直接应用于非 GR 玉米（Zea mays L.）来模拟草甘膦漂移。评估了视觉植物伤害、莽草酸积累、硝酸还原酶活性、叶片氮、产量和种子成分。还在推荐标签率下的 GR 玉米和具有叠氮化抗性基因的 GR 玉米中评价了这些效果，在 3 和 6 WAP 时。105 g ae/ha 的草甘膦在种植后 3 或 6 周时一次性施用于非 GR 玉米。在 3 和 6 WAP 时，将 840（标签下限）或 1260（标签上限）g ae/ha 的草甘膦两次施用于转基因玉米。与未处理的玉米相比，草甘膦在非 GR 玉米中引起了 45-55%的伤害并增加了 24-86%的莽草酸水平。在非 GR 玉米中，草甘膦漂移不会影响淀粉含量，但会增加 8-21%的种子蛋白质，同时降低 46-64%的叶片氮还原酶活性、7-16%的叶片氮、49-54%的谷物产量和 18-23%的种子油。在 GR 和与草铵膦抗性基因叠加的 GR 玉米中，以标签率施用的草甘膦不会影响玉米产量、叶片和种子氮或种子成分（蛋白质、油和淀粉含量）。然而，在 GR 和与草铵膦抗性基因叠加的 GR 玉米中，草甘膦在 840+840 g/ha 率下的硝酸盐还原酶活性降低了 5-19%，在 1260+1260 g/ha 率下降低了 8-42%。这些结果表明，暴露于草甘膦漂移的非 GR 玉米可能会严重减产。