论文部分内容阅读
为了探索控制水稻根系发育， 进而控制地上部生长的途径， 设置了不同施氮量和施肥方法试验， 明确： （１） 水稻整根及其各层次根系的干重和体积， 与施氮量呈抛物线型关系， 以１ｍ ２ 施Ｎ１５ｇ 为最大， 无Ｎ 区次之， 高Ｎ 区最小， 并出现浅根化趋势。肥料深施则增进下层根的发育， 使根系在土壤中趋于均匀分布。（２） 水稻地上部干物质积累量和产量， 与施氮量也呈抛物线型关系， 以１ ｍ ２ 施Ｎ１５ｇ 为最高， 高Ｎ 区次之， 无Ｎ 区最低。肥料深施的地上部干物质积累量和产量略有增加。（３） 冠根比随着施氮量的增加而提高。贫Ｎ 诱发根系竞争性生长； 提高供 Ｎ 水平，地上部干重增长速率高于地下部； 过高的Ｎ 素营养则抑制根系伸长， 但单位根重的活力明显增强。暗示水稻存在一种维持地上下部形态与机能平衡的机制。结果表明， 通过调节养分供应强度和改进施肥方法， 可以控制根系的发育
In order to explore ways to control the root development of rice and control the growth of shoots, different nitrogen rates and fertilization methods were set up to make clear: (1) The dry weight and volume of roots and their roots in rice Parabolic relationship, with N15g 1m2 as the largest, N-followed by the highest, the highest N-area minimum, and shallow rooting trend. Deep application of fertilizers enhances the development of the underlying roots, allowing the root system to be evenly distributed in the soil. (2) The dry matter accumulation and yield of aboveground rice also showed a parabola relationship with nitrogen application rate. N15g was the highest at 1 m 2, followed by high N, and lowest in N. Fertilizer application of aboveground dry matter accumulation and yield increased slightly. (3) Crown-root ratio increased with the increase of nitrogen application rate. N deficient N induced root competitive growth. Increasing the N supply level increased the above-ground dry weight growth rate above ground level. Excessively high N nutrition inhibited root elongation, but the root activity per unit weight was significantly enhanced. Suggesting that rice has a mechanism to maintain the balance between the morphology and function of the above and below the ground. The results showed that root development could be controlled by adjusting nutrient supply intensity and improving fertilization methods