麦田土壤杂草种子库研究

调查分析了8个稻茬小麦田块及不同土层深度的杂草种子种类和数量,结果显示:稻茬翻耕麦田土壤种子库主要杂草种类有菵草、旱苗蓼、野老鹳草和日本看麦娘等,其中菵草所占比例最高,同时在0~20 cm土层内,随土壤深度的加深,杂草的种子数呈下降趋势。0~5 cm土层菵草种子数(x)与田间菵草出苗数(Y)之间符合Y=2.000 0E-0.700 0x2 0.001 1x 242.410 0回归模型,据此可以根据土壤中杂草种子数量预测田间出苗数。

Seed Bank of Weeds in Wheat Fields

The species and quantity of weeds at different soil depths in eight wheat fields interplanted with rice were investigated.The seed bank of weeds in these fields was dominated by American slough grass Beckmannia syzigachne(Steud.)Fern],dock leaved knotweed(Polygonum lapathifolium L.),Carolina geranium(Geranium carolinianum L.)and Japanese alopecurus etc.,with American slough grass holding the most proportion.As the soil went deeper and deeper from 0 cm to 20 cm,the quantity of weed seeds became less and less.The seed number(x) and seedling number(Y) of American slough grass accorded with the regression model Y=2.000 0E-0.700 0x~2 0.001 1x 242.410 0 which could be the basis to forecast the seedling number of weed according to seed number of weed in the soil.