Effect of balanced fertilizers on pineapple yield and quality in Guangxi
IPNI-2008-CHN-GX10
03 Feb 2011
2010 Annual Interpretive Summary
Effect of Balanced Fertilization on Papaya Yield and Quality in Guangxi, 2010
The objective of this study was to evaluate the effects of different fertilizer treatments on fruit yield and quality of papaya grown at two locations in Guangxi, Nanning City and Wuming County. There were eight treatments including: an optimal (OPT) treatment; treatments individually omitting N, P, K, Mg, B, and Zn within the OPT; and the OPT + Mo. The OPT treatment was based on soil testing and preliminary research and was set at 900-190-960 kg N-P2O5-K2O/ha, plus 130 kg MgO/ha, 4.0 kg borax/ha, and 4.0 kg zinc sulfate/ha. The Mo fertilizer used was ammonium molybdate.
Papaya yields responded significantly to N, P, and K application at two sites in spite of the considerable difference in their productivity. At Nanning, yields were reduced by 18.6 t/ha (-42%), 8.6 t/ha (-19%), and 5.6 t/ha (-13%) with omission of N, P, or K, respectively. At Wuming, yields were reduced by 9.4 t/ha (-31%), 4.6 t/ha (-15%), and 3.5 t/ha (-12%) with omission of N, P, or K, respectively. Omission of Mg or Zn reduced papaya yield by 3 to 5%, while omission of B had little effect on yield. Addition of Mo only slightly improved yield (+2%), which implies that the critical value for B needs to be adjusted as soil testing did indicate existing deficiencies.
Agronomic efficiencies for N, P, K, Mg, Zn, and Mo application at the two sites were 11 and 21 kg fruit/kg N; 24 and 45 kg fruit/kg P2O5; 4 and 6 kg fruit/kg K2O; 8 and 12 kg fruit/kg MgO; 51 and 2,221 kg fruit/kg Zn, and 233 and 2,410 kg fruit/kg Mo, respectively. The net income from the OPT treatment was significantly higher than all nutrient omission treatments at USD 17,000/ha at Nanning and USD 12,400/ha at Wuming. Guangxi-BFDP-08