减施化肥配施有机肥对荔枝生长、产量品质及肥料利用率的影响

针对我国荔枝园化肥施用量过高而存在的土壤质量下降、酸碱失衡和产量下降等问题，综合考虑荔枝施肥养分投入与带走量，研究减施化肥配施有机肥对荔枝生长、产量品质及肥料利用率的影响，旨在为荔枝提质增效提供施肥指导。以妃子笑荔枝为研究对象，设置单施化肥（CF）、减施化肥30%分别配施普通商品有机肥5kg/株（OF5）和10kg/株（OF10）、减施化肥30%配施生物有机肥5 kg/株（BIO5）和10kg/株（BIO10）5个处理，比较不同施肥处理对荔枝生长、养分供应、产量品质、肥料利用率及经济效益的影响。结果表明：（1）化肥减施30%的情况下，配施有机肥未明显减缓荔枝梢期生长。与CF相比，OF5显著促进新梢生长，BIO5显著提高梢期叶片叶绿素含量（SPAD值）；有机肥处理的百叶重及梢粗较化肥处理显著降低。（2）总体来看，在梢期与果实成熟期，各处理间叶片养分含量无显著差异，在二蓬梢期及末次梢期，OF10与BIO5叶片氮含量显著高于CF处理；各处理叶片氮含量均处于适宜范围，各养分含量与变化趋势均符合荔枝生长规律。（3）与CF相比，BIO5、OF10、BIO10处理均显著提高荔枝单株产量，其增幅分别为44.77%、35.81%、18.23%；有机肥处理均有提高荔枝单果重、纵径与横径的趋势；有机肥处理下荔枝果实内在品质高于CF处理，可溶性固形物含量平均增加1.76%-3.22%，可溶性糖含量平均增加11.96%-21.84%，可滴定酸含量平均降低15.38%-35.35%；产量品质综合评价BIO5>BIO10>CF>OF10>OF5。（4）各有机肥处理氮素偏生产力均显著高于化肥处理，BIO5与OF10氮、磷、钾肥偏生产力与农学利用率均显著高于其它处理。OF10、BIO5、BIO10均能显著提高荔枝收益。综合考虑荔枝生长、果实产量及品质、肥料利用效率以及经济效益，该园区在减少30%化肥养分投入下株施5kg生物有机肥处理表现最佳，其次是株施10kg普通商品有机肥。

Effects of Reduced Chemical Fertilizer with Organic Fertilizer Application on Growth, Yield, Quality and Fertilizer Utilization Rate in Litchi

Excessive use of chemical fertilizers led to the degradation of soil quality, resulting in soil acidification and poor yield. Based on the nutrient input and removal of litchi fertilization, the growth, yield and quality of litchi and fertilizer utilization rate were explored to study the effects of reduced chemical fertilizer with organic fertilizer application, aiming to provide a theoretical basis of reasonable fertilization for improving the quality and efficiency of litchi. A field experiment of Feizixiao litchi were conducted in Hainan, including 5 treatments:100% chemical fertilizer (CF), 70% chemical fertilizer + 5 kg/plant commercial organic fertilizer (OF5), 70% chemical fertilizer + 10 kg/plant commercial organic fertilizer (OF10), 70% chemical fertilizer + 5 kg/plant bio-organic fertilizer (BIO5), 70% chemical fertilizer + 10 kg/plant bio-organic fertilizer (BIO10). The results showed that:compared with CF, OF5 significantly promoted the growth of young shoots. There were no significant differences in leaf nutrient contents among all treatments at branch or mature stages. At the second and last branch stages, the leaf nitrogen contents of OF10 and BIO5 were significantly higher than CF. The leaf nutrient contents of each treatment were in the appropriate range, and the trend were in line with the growth law of litchi. BIO5, OF10 and BIO10 significantly improved the per plant yield compared with CF. The organic fertilizer treatment could improve the internal quality of fruit, the averaged increase of soluble solid and soluble sugar contents in all organic fertilizer treatments were 1.76%-3.22% and 11.96%-21.84%, and the decrease of titratable acid content were 15.38% to 35.35%. The comprehensive evaluation result of yield and quality was BIO5>BIO10>CF>OF10>OF5. Compared with CF, the partial factor productivity of N in organic fertilizer treatments was significantly increased, BIO5 and OF10 significantly improved the partial factor productivity and agronomic utilization of N, P and K, compared with other treatments. OF10, BIO5 and BIO10 could significantly increase the economic benefits of litchi compared with OF5 and CF. Considering the growth of litchi, fruit yield and quality, fertilizer utilization efficiency and economic benefits, reducing 30% chemical fertilizer combined with 5 kg/plant (2 700 kg/hm²) bio-organic fertilizer or 10 kg/plant (5 400 kg/hm²) commercial organic fertilizer were the optimal treatments in this area.