一年生野生大豆植株基部休眠芽萌动与刈割时间的关系

为探究一年生野生大豆(Glycine soja Sieb.et Zucc.)植株基部腋芽的萌动特性,分别在主茎第2、3、4、5、6、7和第8复叶期(20007年5月至8月底)于第1复叶节和第2复叶节之间切除主茎,在剪切后第0、2、4、8、12 d观测各处理主茎基部新生芽(茎)数以及残茬中可溶性碳水化合物含量。结果表明:一年生野生大豆子叶节上对生着2个腋芽,其只有在主茎第4复叶展开前打顶刺激下才能萌动生长,否则枯死;单叶节上也存在2个对生的腋芽,无论主茎剪除与否,均可萌动生长成分枝;第1复叶节上存在多个腋芽,在节上存在分枝的情况下,剪除主茎仍能刺激节上休眠腋芽的萌动。主茎剪除后,残茬中可溶性糖含量短期内显著下降(P<0.05);不同生长期刈除主茎,其残茬可溶性糖含量的变化趋势无显著差异,且与残茬上休眠芽的萌动和生长无明显的相关关系。因此推测,一年生野生大豆植株基部休眠芽在较短生长时期内便失去萌动能力,早期刈割和提高留茬高度是确保刈割后再生的重要措施。

Relationship between Germinating of Axillar Buds at the Base Node and Main Stem Removing Time in Annual Glycine soja Sieb.et Zucc.

In order to investigate the germinating ability of axillar buds,the experiments were conducted using pot planting annual wild-type soybean(Glycine soja Sieb.et Zucc.) between May 2007 through August 2007.Main stems were cut between the 1st compound leaf nodes and the 2nd compound leaf nodes at the 2nd、3rd、4th、5th、6th、7th and 8th compound leaf stage,respectively.Numbers of germinating buds and branchs as well as contents of water-soluble carbohydrate(WSC) were determined in 0、2、4、8、12 days after cutting.The results showed that two opposite axillary buds from cotyledon node could only germinate when main stem was cut before the 4th compound leaf stage.Regardless of whether the main stem was cut or not,two opposite axillary buds from a single leaf node could germinate.When there were more than two axillary buds or several branches at the 1st compound leaf nodes,the buds still could be stimulated to germinate after cutting their main stem.The content of WSC decreased significantly,but no significant differences were observed among the decribed cutting treatments(P<0.05).The results suggested that axillary buds in annual wild-type soybean plant could cose their ability to germinate,so cutting at early growth stage and increasing cutting height were important to ensure re-growth in cultivation.