Abstract:
Pot experiments were carried out to study of effects of micropore potassium-silicon-calcium (PSC) mineral fertilizer (a national invention patented product) on rice growth, yield and soil physical and chemical characteristics in brown-humid soils. Five treatments were designed, i.e. zero fertilization (T1), conventional fertilization (T2), conventional fertilization plus micropore PSC mineral fertilizer at 4 g·pot
-1 (T3), conventional fertilization plus micropore PSC mineral fertilizer at 8 g·pot
-1 (T4), and conventional fertilization plus micropore PSC mineral fertilizer at 12 g·pot
-1 (T5). Compared with T2, results showed that the application of micropore PSC mineral fertilizer reduced soil bulk density by 0.04 g·cm
-3. It also increased soil porosity, pH and contents of soil available silicon and potassium by 1.8%, 0.1, 9.4~27.0 mg·kg
-1 and 10.6~39.7 mg·kg-1, respectively. Compared with T2, micropore PSC mineral fertilizer increased not only leaf chlorophyll content, but also rice flag leaf area by 4.8 cm
2. It also increased effective panicle numbers by 2.3~5.0 spike·pot
-1, 1000-grain weight by 0.1~1.9 g and average yield by 13.6%. Recovery rates of N, P, K increased by 0.6%~7.5%, 0.1%~1.5% and 8.5%~13.5%, respectively. Based on rice yield, the optimal recommended economic application rate of micropore PSC mineral fertilizer was 4 g·pot
-1 equivalent to 450 kg·hm
-2 in brown-humid soils.