土壤酸化对双季早、晚稻产量的影响

土壤pH是影响水稻生长的重要因素,目前还不清楚土壤酸化对双季水稻产量的影响。本研究利用硫酸调节土壤pH结合移栽后浇灌不同pH的水使土壤酸化。结果表明,随着土壤pH的下降,双季早、晚稻生育期延长,物质生产量下降,产量降低,当浇灌水pH下降至4.5以下,土壤pH下降至5.0以下时,双季早、晚稻产量下降明显,其中早稻平均下降7.82%,晚稻平均下降8.06%;当浇灌水pH下降至3.5以下,土壤pH下降至4.5以下时,双季早、晚稻产量下降幅度更大。土壤酸化主要抑制双季早、晚稻前期分蘖的发生,导致每穗粒数降低,结实率和千粒重也表现出下降的趋势。

Effects of Soil Acidification on the Yield of Double Season Rice

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 yieldof double season rice decreased even more sharply. Under the condition of soilacidification, 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.