深旋松耕作法对东北棕壤物理性状及春玉米生长的影响

【目的】探讨深旋松耕作法在东北地区玉米生产上的可行性。【方法】在辽宁省昌图县设置土壤耕作试验，以旋耕（R）和深松耕（S）为对照，对比研究深旋松30 cm（DRS30）、深旋松30 cm+地膜覆盖（DRS30P）、深旋松50 cm（DRS50）、深旋松50 cm+地膜覆盖（DRS50P）对土壤某些物理性状、玉米根系、植株生长发育和作物产量等的影响。【结果】（1）深旋松可有效打破犁底层，显著改善土壤某些物理性状。四组深旋松处理的土壤容重均低于对照，DRS50P最低，R最高。DRS50P和DRS30P土壤温度、土壤含水量高于其它处理；DRS50和DRS30苗期含水量低于其它处理，其它时期高于对照。DRS50P与DRS30P、DRS50与DRS30土壤某些物理性状差异显著。（2）深旋松促进了玉米根系生长。拔节期和灌浆期，DRS50P和DRS30P的根数、根长、根体积及根冠比显著高于DRS50 和DRS30，DRS50 和DRS30高于对照，R最低；成熟期DRS50P和DRS30P的根长和根数最大，根体积和根冠比略低于其它处理。DRS50P与DRS30P、DRS50与DRS30植株性状差异较小。（3）深旋松促进了玉米地上部生长发育，增加了籽粒产量。DRS50P和DRS30P显著增加了玉米穗长、穗粗、行粒数和百粒重。DRS50P获得最高产量，DRS30P次之，分别为12 137.4 kg?hm-2、11 929.2 kg?hm-2。两者差异未达显著水平，但均显著高于其它处理。DRS50P和DRS30P分别比R增产23.0%和20.8%，分别比S增产14.1%和12.1%。【结论】综合作业成本和动力消耗等因素，DRS30P更具推广价值。

Effects of Deep Rotary-Subsoiling Tillage Method on Brown Physical Properties and Maize Growth in Northeast of China

【Objective】 The feasibility of deep rotary-subsoiling tillage method in maize production was explored in northeast of China.【Method】The designed six tillage treatments were rotary tillage (R), subsoiling tillage (S), deep rotary-subsoiling 30 cm (DRS30), deep rotary-subsoiling 50 cm (DRS50), deep rotary-subsoiling 30 cm+plastic film mulching (DRS30P), deep rotary-subsoiling 50 cm+plastic film mulching (DRS50P). The effects of different tillage methods on some soil physical properties, maize root, spring maize growth and crop yield were measured in Changtu county of Liaoning province. R and S were set as the control．【Result】Deep rotary-subsoiling treatments could effectively break plow pan, significantly improved some soil physical properties. The soil bulk density of deep rotary-subsoiling treatments were lower than that of the control (including R and S). DRS50P treatment was the lowest and R treatment was the highest among treatments. Soil temperature and soil water content were higher in DRS50P and DRS30P treatments than other treatments. DRS50 and DRS30 treatments showed the lowest levels in soil water content at seedling stage, DRS50 and DRS30 were the higher than the control at other stages. Some soil physical properties in DRS50P and DRS30P, DRS50 and DRS30 treatments showed significant differences. Deep rotary-subsoiling treatments promoted the growth of maize root system. At jointing and milky stages, DRS50P and DRS30P treatments gained the highest amount of root number, root length, root volume and root shoot ratio, followed by DRS50 and DRS30 treatments. R treatment showed the lowest levels in the above parameters. At maturity stage, root length and root number in DRS50P and DRS30P treatments were the highest, root volume and root shoot ratio were the lower than other treatments. The differences of plant traits in DRS50P and DRS30P, DRS50 and DRS30 treatments were little. Deep rotary-subsoiling treatments promoted maize growth and development of shoot, and increased the yield of grain. DRS50P and DRS30P treatments evidently increased ear length, ear diameter, kernels per row and hundred-kernel weight. DRS50P treatment had the highest grain yield of 12 137.4 kg•hm-2, and grain yield of DRS30P treatment ranked the second places of 11 929.2 kg•hm-2. The differences between DRS50P and DRS30P showed no significant, but were significantly higher than that of other treatments. DRS50P and DRS30P treatments respectively increased yield by 23.0% and 20.8% than R treatment, by 14.1% and 12.1% than S treatment. 【Conclusion】In consideration of the comprehensive operation cost and power consumption, the DRS30P seems worth promoting.