河套灌区晚播向日葵保苗播种技术研究

Research on High Survival Rate Seeding Technology of Late Sowing Sunflower in Hetao Irrigation Area in Inner Mongolia

[目的]为了解决河套灌区晚播向日葵播种中存在的土壤难以保墒而适播期短、种穴覆土遇雨易板结、出苗期鸟鼠危害严重,保苗率低、毁种率高的问题。[方法]从不同土壤保墒、播种、播种穴覆盖等方式,进行了保苗播种技术研究。[结果]研究结果表明,先覆膜后灌水保墒,可大幅度延长土壤水分的适播期;播种穴覆沙可有效解决种穴覆土遇雨板结问题,同时可提高地温、加快出苗进程、降低鸟鼠危害程度,提高保苗率;机械垄上播种种穴覆土板结率较机械覆膜沟种覆土大幅度降低。[结论]播种前地块先覆膜后灌水,土壤含水量降到20%以下后采取人工点播种穴覆盖风积沙的播种模式,是河套灌区最适宜的保苗播种模式。

[Objective]To solve the existing problems in the traditional sowing model, such as low the capacity of soil moisture conservation, short suitable sowing period, hardened and impervious soil around the sowing hole after a rain, birds and rats disaster during the emergence period, low survival rate and high repeating sowing rate, in the sowing of late sowing sunflower in Hetao Irrigation Area. [Method]The high survival rate seeding technology were researched from several aspects including the soil moisture conservation, sowing, sowing hole cover. [Result]The results showed that the suitable sowing period could be greatly lengthened when the plastic film mulching was made before irrigation and soil moisture conservation; the sowing hole covering by sand could effectively solve the problem of hardening and imperviousness of the soil around the sowing hole after a rain, meanwhile, it could improve the ground temperature, promote the process of seedling emergence,reduce the degree of harm made by birds and rats and improve the survival rate of the seedlings. The rate of hardening and imperviousness of the soil around the sowing hole with the machine ridge sowing was lower enormously compared with that of the mechanical film mulching and furrow seeding. [Conclusion]The model, namely, before seeding, the irrigation was made after plastic film mulching and the sowing hole was covered by the wind deposited sand after the manual bunch planting was conducted when the soil water content dropped below twenty percent, was the optimal sowing model for sunflower in Hetao Irrigation Area.