Effects of soil acidification on the yield of double season rice

Abstract

Soil pH is one of the important factors affecting rice growth and development, but little is known about the impact of soil acidification on the yield of double season rice. In the pot experiment, sulfuric acid was added to the soil and low pH water was used for irrigation after transplanting. The results showed that with the decrease of soil pH the plant growth duration extended, the dry mass accumulation and the grain yield decreased in double season rice. When the pH of irrigated water lowered than 4.5 and soil pH lowered than 5.0, the yield of double season rice decreased significantly, by 7.82% for early season rice and by 8.06% for late season rice. When the pH of irrigated water lowered than 3.5 and the soil pH lowered than 4.5, the yield of double season rice decreased even more sharply. Under the condition of soil acidification, the early tillering for double season rice was suppressed, leading to decrease of number of spikelets per panicle, seed setting rate and 1000-grain weight.