Abstract: A pot experiment was conducted to study the seedling emergence of weedy rice in Northern China at different sowing depths.Results showed that the elongation of mesocotyl and internode of coleoptile played important roles in the seedling emergence of the weedy rice from northern China.The mesocotyl of weedy rice elongated at 3 cm sowing depth,but both the mesocotyl and the coleptile elongated at 5 cm sowing depths.The germination dynamics of weedy rice at deep sowing depth depended on the elongation of mesocotyl and coleoptile.

Key words: weedy rice, mesocotyl, internode of coleoptile, elongation, germination dynamics

摘要： 以盆栽的方式，采用不同的覆土深度，对中国北方杂草稻的出苗特性进行了研究，分析了杂草稻的出苗动力源。研究结果表明，在中国北方发现的部分杂草稻具有较强的中胚轴伸长特性和芽鞘节间伸长特性。在播种深度较浅时（3 cm），杂草稻依赖于中胚轴的伸长顶土发芽；当覆土较深时（5 cm），杂草稻中胚轴伸长特性更加明显，伸长长度加大，同时杂草稻的芽鞘节间也明显伸长，中胚轴和芽鞘节间的共同伸长为深覆土条件下杂草稻的出苗提供了动力基础。

关键词: 杂草稻, 中胚轴, 芽鞘节间, 伸长, 出苗动力