Effects of Various Ameliorants on pH, Phosphorus Availability and Soybean Production in Alfisols

Alfisols have inherent potential to increase Indonesia’s soybean production, however, alfisols also known for its low phosphorus availability. Field experiment using ameliorants consisting of quail manure, zeolites and rock phosphate was conducted to increase phosphorus (P) availability and soybean production. The aim of this study is to evaluate the effects of ameliorant combinations for improving phosphorus availability and its correlation to soybean production in alfisols. Randomized complete block design with single factor was used, with 9 combinations of ameliorants under study (P0 – P8). Obtained results showed that phosphorus availability is increased up to 72.6% and soybean yield upto 75.9%. Correlation of phosphorus availability and soybean production was significant (r = 0.854). Finally, the best treatment to increase phosphorus availability and soybean production is quail manure 2.5 t.ha-1 + rock phosphate 5 t.ha-1).