不同种植密度下油菜产量与茎叶性状对施肥水平的反应

为探明种植密度和施肥水平对油菜生长与产量的影响及其机理，此文采用大田小区试验，研究了高、中、低（分别为7.5、22.5、37.5万株/hm2）3种密度条件下冬油菜籽粒产量和茎叶性状对4种施肥水平的反应。结果表明，在供试3种密度条件下，籽粒产量、单株角果数、每角果粒数、千粒重、越冬期和盛花期的根颈直径、越冬期单株绿叶数、盛花期单株主茎绿叶数、越冬期最大叶长和宽、盛花期第一片无柄叶长和宽均随着施肥量的增加而增加，但增加幅度因密度不同而异，籽粒产量和越冬期根颈直径在中密度条件下、其余各项指标在低密度条件下增加幅度最大，而在高密度条件下所测各项指标的增加幅度均最小。因此，所有处理中，籽粒产量和越冬期根颈直径以中密度、高施肥量处理（N、P2O5、K2O、B分别为240、120、210、1.2 kg/hm2）的最高，其他各项指标均以低密度、高施肥量处理的最高。不同种植密度下油菜产量与茎叶性状对施肥水平的反应各异，其中以越冬期根颈直径受个体间竞争的影响相对较小，在不同密度条件下随施肥量的变化趋势于籽粒产量一致，所以能更好地反应油菜生长和产量情况。

Responses of Grain Yield and Stem, Leaf Parameters of Oilseed Rape to Applying Fertilizer Levels under Different Planting Densities

A field plot experiment was conducted to study the responses of grain yield and stem, leaves parameters of ‘ Xiang Zayou 763 ’ （a new hybrid variety of winter oilseed rape with high quality） to 4 levels of application fertilizer under planting density conditions of high （375 thousand plants/hm 2 ）, middle （225 thousand plants/hm 2 ） and low （75 thousand plants/hm 2 ）. The results showed that grain yield, siliques per plant, seeds per pod, weight of thousand seeds, diameter of rootstalk at wintering and flowering stages, numbers of green leaf per plant at wintering stage, numbers of green leaf on main stem per plant at flowering stage, length and width of the biggest leaf at wintering stage, length and width of the first leaf without handling at flowering stage increased with fertilizer application amount under 3 kinds of planting density, but the degrees of their increases were different from planting densities. The increased degrees of grain yield, diameter of rootstalk at wintering stages were biggest under the middle planting density, the other indexes heavily increased under low planting density, while under high planting density, the increased degrees of all indexes were small. Therefore,grain yield, diameter of rootstalk at wintering stages at treatments of middle planting density and high application N level increased heavily （N, P 2 O 5 , K 2 O and B were 240, 120, 210, 1.2 kg/hm 2 ）, the increased degrees of other indexes were highest at the treatments of low planting density and high application N levels.