地膜覆盖免放苗栽培对土壤温度及高粱生长的作用效应

摘要 为进一步丰富和完善地膜覆盖免放苗栽培技术，以高粱为指示作物，采用大田试验的方法，测定了地膜覆盖免放苗栽培对土壤温度、高粱出苗、主要农艺性状及产量的影响。结果表明，地膜覆盖免放苗栽培对土壤的增温保温效应明显，0～25 cm土层温度保持在23.90～15.62 ℃，较露地增温3.97～2.24 ℃，利于高粱出苗及壮苗。地膜覆盖免放苗栽培所涉及的地膜种类及其厚度对高粱主要农艺性状和产量均有明显影响，以厚度为0.010 mm的普膜覆蓋表现最好，高粱的出苗率超过93.0%，生育期较露地提前10 d，增产51.95%，茎、穗部性状有明显改善，可大面积推广应用;降解膜覆盖也有较好的表现，高粱的出苗率达到89.4%，生育期较露地提前5 d，增产29.61%，茎、穗部性状也有明显改善，但该种地膜成本较高、分解较快、保墒性较差、杂草危害较重，因此应用受限;银灰双色膜和黑色膜覆盖，高粱的茎、穗部性状表现较好，但明显影响出苗，出苗率不足85%，不宜推广应用。

关键词 地膜覆盖;免放苗;土壤温度;高粱生长;效应

Abstract In order to further enrich and improve the technology of plastic mulching and no seedling cultivation， taking sorghum as an indicator crop， we carried out field experiment to determine the effects of plastic mulching and no seedling cultivation on soil temperature and emergence rate， major agronomic traits and yield of sorghum at the drought area of eastern Gansu Province. The results showed that the technology of mulch over and no seedling cultivation significantly improved and preserved the soil temperature. The soil temperature at 0-25 cm soil depth was maintained at 23.90-15.62 ℃， which increased by 3.97-2.24 ℃ compared with the control group， which suggested that the technology of plastic mulching and no seedling cultivation was beneficial to the emergence rate of sorghum and strong seedlings. Different types and thicknesses of plastic mulch used in the technology of plastic mulching and no seedling cultivation had a significant impact on the main agronomic traits and yield of sorghum. Compared to the control group， the group of a mulch thickness of 0.010 mm showed the optimal production performance. The emergence rate of sorghum exceeded 93.0%， the growth period was 10 d earlier， and the yield increased by 51.95%. Furthermore， the stems and ears of sorghum were significantly improved compared with the control groups， suggesting that it was a highly efficient planting model and would be promoted in large areas. In addition， the group of degradation film cover also showed superior performance than control group. The emergence rate of sorghum was 89.4%. The growth period was 5 days earlier， and the yield increased by 29.61%，the traits of stems and ears also improved significantly. While this kind of plastic mulching had higher cost， faster decomposition， poorer moisture retention， heavier weed damage and limited application. The group of silvergray doublecolor film and black film was beneficial to the stems and ears of sorghum， but the emergence rate was less than 85%. Therefore， these two types of plastic mulching should not be widely promoted.

Key words Plastic film mulching;No seedling release; Soil temperature;Sorghum growth;Effect

地膜覆盖免放苗栽培技术[1]是采用单垄种植，先播种后覆膜，然后给播种行膜面覆土的一种种植方式。该技术巧妙利用作物的趋光性及其锥状芽鞘钻透地膜的特性，不采用人工破膜放苗，实现作物自己顶膜出苗。该技术保证了地膜的完整性，出苗率高、垄面无杂草、保水保肥、节本效应十分显著。该技术能有效解决目前地膜覆盖栽培模式中需要人工放苗、填洞及膜孔杂草丛生等一系列问题[2-5]，也弥补了地膜覆盖穴播种植中杂草掀膜的困扰[6-7]，极大限度地提高了地膜覆盖的水肥利用率，因此推广意义很大。……