Effects On Rice Yield Of Inter-Planting Rice And Weed Chemical Control In Ultra-High Stubble Field Of Wheat

Technique of inter-planting rice in ultra-high stubble wheat field, introduced from Japan in 1980s, has become a novel labor-decreased rice planting system, which has been improved in accordance with our practical situation in China, as well with systemic research and extension in different ecological district for more than ten years. By using this technique, wheat straws can be incorporated into the field and no tillage and no transplanting will be adopted.But weed is the major problem that obstacles its wide application and extention. Our research mainly focused on weed control and effects of this technique on rice yield and economic benefit.The results are as follows:Five different herbicides or their complex were applied after interplant rice in wheat field and secondly applied to the rice roots post wheat harvest, the optimal herbicide is 35.5% Dingeruyou, followed by 100 ml of 30% dichloro bensulfuron-methyl, 200ml 50% benthiocarb plus 15ml 10% bensulfuron-methyl, 50ml 50% mefenacet plus 15ml 10% bensulfuron-methyl and 36% dichloro bensulfuron-methyl. The earlier soil was treated, the better weed was controlled. The effects will last for 45 days.Among which, 35.5% Dingeruyou is safe to rice.The rice yields were compared for three different cultivation methods, that is inter-planting rice in wheat field with ultra-high stubble of wheat, regular rice cultivation and direct sowing of rice. There was no obvious difference between the first two method. Under the same condition,the rice yield of inter-plant cultivation increased with the height of remained straw (from 0 to 30cm). The rice yield with 30 cm remained straw was significantly different from that without straw remained, and the cost will be reduced more than 30%, the benefit increased 35.9%, the labour productivity is 3.8 times of the regular cultivation.