滴灌施肥量对棉花生长、养分吸收及产量的影响

2012年以新陆早33号棉花为供试作物,利用田间小区试验研究了大田膜下滴灌施肥条件下,不同滴灌施肥量对棉花植株氮、磷、钾养分的吸收、干物质积累及籽棉产量的影响。设置了5个N-P2O5-K2O施肥水平150-60-30、200-80-40、250-100-50、300-120-60 kg·hm-2和350-140-70 kg·hm-2(分别记为F1、F2、F3、F4和F5),灌水量为100%ETc(作物蒸发蒸腾量)。结果表明:在新疆膜下滴灌条件下,棉花干物质积累与氮、磷、钾养分吸收和吸收速率均随着滴灌施肥量的增加呈增大的趋势,施肥量达到F4时,棉花的干物质累积和氮、磷、钾的吸收和吸收速率最大;随着施肥量的增加,棉花产量有增加的趋势,但当施肥量大于F3,棉花产量随施肥量的增加(F3,F4,F5)无显著性差异;F3施肥水平下的氮肥农学效率、磷肥农学效率、钾肥农学效率和肥料偏生产力显著大于F4与F5施肥水平。从节肥和生态可持续发展角度来看,F3施肥水平,即250-100-50 kg·hm-2(NP2O5-K2O)为最佳滴灌施肥量。

Dosage effects of dripping fertilization on cotton growth, nutrient uptake and yield

The cotton species, XinLuzao 33, was tested through field plot experiments at the Water-saving Irrigation Station of Xinjiang Academy of Agricultural and Reclamation Science in 2012. The effects of fertilization levels were evaluated on the uptakes of nitrogen, phosphorus and potassium by cotton, dry matter accumulation and yield under mulched drip fertigation. There were five fertilization levels of N-P₂O₅-K₂O (150-60-30, 200-80-40, 250-100-50, 300-120-60, 350-140-70 kg·hm^-2, as F1, F2, F3, F4 and F5, respectively) and the irrigation level was set as 100% ET_c(the crop evapotranspiration). Results showed that the dry matter accumulation, the uptakes of N, P₂O₅, K₂O and their uptake rates were elevated with the increase of fertilizer amounts, which reached maximum values at the F4 level. Cotton yield had a tendency to become increased with escalation of fertilizer amount, but there were no significant differences between F3, F4 and F5. The AEN, AEP, AEK and PEP at the F3 level were significantly larger than those at the F4 and F5 levels. In terms of fertilizer saving and ecological sustainable development, the F3 level with N-P₂O₅-K₂O of 250-100-50 kg·hm^-2 was suggested be the optimal fertilization application. This study could provide valuable information for improving the management of cotton under mulched drip fertigation in Xinjiang.