硫对水稻产量的影响及缺硫诊断研究

Diagnosis of Sulfur Deficiency and the Effect of Sulfur on Rice Grain Yield

为研究硫对水稻产量的影响，确定缺硫诊断指标，进行了水培和大田试验。结果：①施硫可提高水稻有效穗、结实率和千粒重，产量较缺硫处理有极显著的增加；有效硫含量中等的沙质田，硫肥（石膏）用量以含纯Ｓ１５ｋｇ／ｈｍ２为宜。②不同生育期缺硫对水稻产量的影响不同，分蘖期缺硫对产量影响最大，其次是苗期和抽穗期，生产上硫肥宜作基肥施用。③水稻缺硫诊断的适宜部位是叶片，分蘖期水稻硫素营养诊断的临界值是：硫酸盐硫（Ｓ）１９０μｇ／ｇ，全硫（Ｓ）０．１１％；Ｎ／Ｓ比值３１。

The field and hydroponic experiments were conducted to confirm the effect of sulfur on rice grain yield and diagnostic index of sulfur deficiency,the results showed as follows:①Fertilization of sulfur enhanced the number of effective panicles,percentage of filled grain and 1000grain weight,significantly increased the grain yield .In sandy soils,which contained medium available sulfur,the proper doses of sulfur fertilizer was 15 kg per hectare.②The effect of sulfur deficiency on rice grain yield was more serious at tillering stage than that at seedling and ear developing stage.Sulfur fertilizer should be applied as basic fertilizer.③The proper organ for sulfur diagnosis was rice leaves.Total sulfur,sulfatesulfur and N/S ratio could be used for sulfur diagnosis and the critical levels were 011%,190 μg/g and 31 respectively at tillering stage.