摘要
采用添加系列试验和模型拟合的方法研究了不同野燕麦密度下油菜各生长性状的变化规律。结果表明,油菜在野燕麦的竞争干扰下,植株高度、分枝数、角果数及千粒重均随其密度的增加而显著降低,而第一分枝高度则不断增加。野燕麦能显著降低油菜植株间的透光率,其对田间25 cm高处的透光率影响较大,对75 cm和50 cm高处的透光率影响相对较小。野燕麦密度为5株.m-2时油菜产量显著降低,当其密度达到160株.m-2以上时,可使油菜减产达90%以上。对数模型y=15.436 lnx+8.475可以较好地拟合野燕麦与油菜产量损失间的关系(P<0.000 1)。油菜田野燕麦人工防除的经济阈值为1.15株.m-2,使用精噁唑禾草灵化学防除的经济阈值为0.70株.m-2。
Additive series experiment and regression fitting methods were used to study the influence of Avena fatua on growth and yield of oilseed rape （ Brassica napus L. ） under field conditions. The results showed that increasing density of A. fatua significandy reduced plant height, branching number, pod number and 1 000-grain weight of rape, but increased the height of first branch. The light penetration rate in rape fields was reduced significandy with the presence of A.fatua, and the reduction at the height of 25cm was greater than that of 75cm and 50cm. Yield of oilseed rape could be heavily reduced when A.fatua density was above 5 plant·m^-2 ,and the yield loss could reach 90% when A. fatua density was above 160 plant·m^-2. The logarithmic regression model y = 15. 436 lnx ＋ 8. 475 was the best in describing the relationship between A. fatua density and yield loss of oilseed rape （P 〈0. 0001 ）. In rape fields ,the economic threshold of A.fatua was 1.15 plant·m^-2 for manual weeding and 0.70 plant·m^-2 for fenoxaprop-P-ethyl chemical control.
出处
《中国油料作物学报》
CAS
CSCD
北大核心
2009年第2期233-238,共6页
Chinese Journal of Oil Crop Sciences
基金
国家"十一五"科技支撑项目(2006BAD08A09)
湖北省科技攻关项目(2006AA201B19)
湖北省重点科学技术研究项目(992P0504)
关键词
野燕麦
油菜
透光率
经济阈值
Avena fatua
Oilseed rape
Light penetration rate
Economic threshold
