Effect of balanced fertilizers on pineapple yield and quality in Guangxi
IPNI-2008-CHN-GX10
15 Feb 2010
2009 Annual Interpretive Summary
Effect of Balanced Fertilization on Pineapple Yield and Quality in Guangxi, 2009
This study continues to evaluate the effects of different fertilizer rates and combinations on fruit yield and
quality of pineapple grown in Guangxi. Thirteen treatments tested four rates of N (0, 188, 375, and 562 kg/ha), four rates of P (0, 75, 150, and 225 kg P2O5/ha), four rates of K (0, 300, 450, and 600 kg K2O/ha), Mg at 54 kg MgO/ha, B at 4.5 kg borax/ha, and Zn at 4.5 kg zinc sulfate/ha. The optimum (OPT) treatment, based on soil testing and preliminary research, was set at 375-150-450-54 kg N-P2O5-K2O-MgO/ha.
Pineapple yields responded to N, P, and K application and reached a peak yield of 35 t/ha under the OPT. Yields were reduced when application rates of N, P, and K were either below or above the OPT. Removing Mg from the OPT also resulted in a significant (-10%) yield reduction. Similar to the previous results, addition of Zn along with the OPT did not improve yield, whereas addition of B significantly reduced yield. Critical values for these micronutrients need to be adjusted since soil testing did indicate existing deficiencies. Agronomic efficiencies for the macronutrients were higher than in 2008 and ranged from 29 to 58 kg fruit increase/kg N applied, 26 to 44 kg fruit increase/kg P2O5, and 38 to 60 kg fruit increase/kg K2O. The net income from the OPT treatment was US$6,035/ha, which was significantly above the other imbalanced fertilizer treatments. Guangxi-BFDP-08