除草剂对苘麻子代萌发和幼苗生长的延迟影响

以我国本土野生植物苘麻为研究对象，通过盆栽和萌发实验，研究了苯磺隆和莠去津2种除草剂施用于苘麻花期对收获种子的萌发和幼苗生长的影响.结果表明，苯磺隆和莠去津均对苘麻繁殖具有延续影响.苯磺隆对苘麻的种子萌发百分率和平均发芽时间影响不显著，而使种子萌发初始时间提前或推迟，随着浓度增加变化无规律性.大田推荐剂量浓度的苯磺隆（22.5g ai/hm²）抑制第7天幼苗生长特别是子叶下胚轴生长，而低于大田推荐剂量的6个浓度均促进第7d幼苗生长.大田推荐剂量浓度1/16的莠去津（75g ai/hm²）处理后所获得种子萌发百分率显著高于空白对照和其它处理获得的种子萌发百分率，施用大田推荐剂量（1200g ai/hm²）和大田推荐剂量浓度1/4的莠去津（300g ai/hm²）使种子初始萌发时间显著推迟.莠去津使种子平均发芽时间显著增加，大田推荐剂量浓度1/64（0.35g ai/hm²）和1/4的莠去津抑制第7天幼苗生长.

Seed germination and seedling growth of seed from velvetleaf treated by herbicides

For further study the ecological risk of herbicides and the carry-over effect of herbicides on plant reproduction, the pot and germination experiment were used to investigate the effect of tribenuron-methly or atrazine treated on flowering stage of velvetleaf (Abutilon theophrasti Medicus) on the offspring germination and seedlings growth. The result shows that tribenuron-methly and atrazine both had a carry-over effect on velvetleaf reproduction. Tribenuron-methly had no significant effect on germination percentage and mean germination time (MGT) of seeds. Initial germination time was irregularly changed (advance or delay) with the increase of tribenuron-methly concentration. Radicle growth of seedlings (7days) were inhibited by the recommended field application concentration (RFAC) (22.5g ai/hm²) of tribenuron-methly, with promoted by the others doses. Seed germination percentage from parent plants treated by 1/16of RFAC (75g ai/hm²) of atrazine was significantly higher than that treated by other doses. The initial germination time were delayed significantly when parent plants were treated by RFAC (1200g ai/hm²), 1/4of RFAC (300g ai/hm²) of atrazine. MGT of seeds from parent plants treated by atrazine significantly increased, and seedlings growth was inhibited when parent plants were treated by 1/64 (18.75g ai/hm²), 1/4 of RFAC of atrazine.