稻草覆盖还田量对郴州烟田土壤温度及烤烟生长发育的影响

为进一步推广烟田稻草覆盖还田技术，2012年在湖南郴州进行大田试验，研究了不同稻草覆盖还田量对烟田土壤温度与烤烟生长发育及产量的影响。结果表明：稻草覆盖影响土壤温度，6月中旬以前表现为“降温”效应，之后表现为“调温”效应；稻草覆盖可使烤烟成熟期推迟1～2 d，可改善烟株的农艺性状，稻草还田量为4000 kg／hm^2表现最好；稻草覆盖可使烟株旺长期后干物质积累量增加，对提高中上部叶的单叶重、叶长与叶宽有一定作用；稻草覆盖对烤烟单叶重、上中等烟比例和均价无明显影响，但有一定增产增效作用，以还田量4000 kg／hm^2效果最好。

Effects of Amount of Rice Straw Returning to Field by Mulching on Te mperature of Tobacco Field Soil,Growth and Development of Flue-cured Tobacco in Chenzhou,Hunan Province

For further extension of technique of rice straw returning to tobacco field,a field experiment was conducted in Chenzhou,Hunan in 2012 to study the effect of rice straw returning to field by mulching on temperature of soil,growth and development and yield traits of flue -cured tobacco.The results showed that soil temperature was affected by rice straw mulching,it showed decrease effect before mid-June and adjusting effect after middle decade of June.Rice straw mulching appreciably delayed the maturity of tobacco 1 ～2 d,improved agronomic characters of tobacco plants and the best effect was observed in treatment of rice straw 4000kg/hm^2.Rice straw mulching improved the dry matter accumulation of tobacco plants after rapid growth stage and weight per leaf,length and width of middle and upper leaves.Rice straw mulching had no clear effect on weight per leaf,average price,medium and first-class leaf proportion,while improved the yield and output value of flue-cured tobacco and the best effect was observed in treatment of rice straw 4000kg/hm^2.