不同施氮量对水稻土氮素供应及烤烟生长的影响

Effects of Different Nitrogen Application Amounts on Nitrogen Supplyand Flue-Cured Tobacco Growth in Paddy Soil

以烤烟云烟97为材料,在云南省临沧地区,通过田间小区试验,研究不同的施氮量对水稻土氮素供应及烤烟生长发育的影响。结果表明:各处理叶面积系数、农艺性状及根冠比均随着施氮量的增加而增加,其中施氮量75 kg/hm^(2)(N3)的烟株能正常落黄,农艺性状最好;而施氮量90 kg/hm^(2)(N4)烟株贪青晚熟,品质低劣;不施氮烟株均早衰、长势较弱或生长不整齐;土壤氮矿化量也在一定程度上影响氮的供应。试验结果表明,当施氮为75 kg/hm^(2)时,可促进根冠平衡,使烟株稳健生长,对提高烤烟品质有正向作用。

Using flue-cured tobacco Yunyan 97 as the material,the effects of different nitrogen application amounts on paddy soil supply and flue-cured tobacco growth were studied by field trials in Lincang of Yunnan province.The results showed that the leaf area coefficient,agronomic characteristics and root/shoot ratio of each treatment increased with the increasing of nitrogen application amount.Tobacco plants with a nitrogen application rate of 75 kg·hm^(–2) could turn yellow normally and had the best agronomic characteristics.90 kg·hm^(–2) tobacco plants were greedy for green and late maturity,and the quality was inferior;the tobacco plants without nitrogen application all age prematurely,grow weakly or irregularly.The amount of soil nitrogen mineralization also affected the supply of nitrogen to a certain extent.Under the experimental conditions,it can be concluded that when the nitrogen application is 75 kg·hm^(–2),the root and shoot balance can be promoted and the tobacco plants can grow steadily.