减量施氮对蕉园土壤养分、农艺性状及产量的影响

香蕉生产中偏施氮肥的现象仍然普遍存在,减少氮肥投入是有效实现化肥总量施用措施。本研究在传统施肥水平基础上,梯度降低氮肥的施用量,测定蕉园土壤养分淋失、农艺性状及产量等指标。结果表明:不同生长期各处理株高、茎围和青叶数等指标均比对照处理生长效果好,在营养生长期株高、茎围及青叶数最高值为T_3、T_3、T_4处理,分别比对照(CK)高14.2%、16%和19.8%,与对照处理(CK)达到显著差异;减少氮肥使用可有效降低氮肥的淋溶,其中在T_1~T_5处理20~60 cm土层NH_4~+-N含量较对照分别减少了47.4%、51.3%、30.5%、58.3%和92.1%;施用70%当量氮肥,香蕉产量和经济效益最优,分别比对照和常规性施肥每公顷增加26.4%和4.8%。

Effects of Reduced Nitrogen Application on Soil Nutrient and Banana,Agronomic Trait and Yield in Banana Plantation

It is very common to apply nitrogen fertilizer at a high rate in banana production. It is an effective measure to reduce total fertilizer input by reducing nitrogen fertilizer input. Banana plants were treated with nitrogen fertilizer at a reducing ingredient rate based on the traditional application rate to determine the soil nutrient leaching loss and their agronomic traits and yield. The results showed that the plant height, stem girth and number of green leaves of the treated banana plants were higher than those of the CK at different growing stages. The plant height, stem girth and the number of green leaves of the treatments T3, T3 and T4 were 14.2%, 16% and 19.8% higher than those of the CK, significantly different from those of the CK at the vegetative growth stage. Low application of nitrogen fertilizer effectively reduced nitrogen leaching. The NH4+-N content in the soil of 20 to 60 cm was reduced by 47.4%, 47.4%, 51.3%, 58.3%, 92.1%, respectively in the treatments T1 to T5 as against the CK. Banana plants treated with 70%of the N fertilizer produced optimum yield and economic benefits, increasing by 26.4%and 4.8%per hectare as compared to the CK and the conventional application of N fertilizer.