ABSTRACT
Poor soil aeration is a limiting factor that influences rice (Oryza sativa L.) growth. Oxygenated compound fertilizer (OCF) is a vital strategy to address this challenge by improving soil aeration. Three kinds of newly developed fertilizers amended with different amounts of calcium peroxide (OCF1, OCF2, and OCF3) were prepared by mixing nutrients and other additive materials. Using waterlogging (WL), micro-bubble aerated water irrigation (MBWI), and fertilization of calcium peroxide for four times (FCP) as check, effects on soil aeration, physiological characteristics, and yield of rice with two rice varieties (Q681 and EK1) were examined in a pot culture. The results showed that OCF achieved a higher soil Eh and dissolved oxygen at the main growth stages and had higher nitrification intensity with lower de-nitrification intensity at tiller stage and full heading stage compared to WL/MBWI/FCP. Compared to WL/MBWI/FCP, OCF3 has 5–76% higher soil NH4+-N and 0–33% higher soil NO3–N, respectively. OCF3 increased the photosynthesis rate, stomatal conductance, and transpiration rate by more than 11%, 21%, and 7% compared to WL, respectively. OCF3 improved 1.07 times of rice yield than WL and has more than 29–58% rice yield than MBWI/FCP. OCF3 kept good soil aeration with long periods, being low price and user-friendly, and could be especially useful in paddy soil under long-term waterlogging.
Acknowledgments
Thanks to D.L. Qi for the grammatical editing.