冬小麦对硫的吸收及在体内的分布规律

通过池栽试验,研究了冬小麦的需硫规律。结果表明：供硫充足的小麦,植株硫的累积呈一单峰曲线,在拔节至抽穗期吸收量最高。而全硫含量在返青起身期有一个高峰,之后随着小麦的生长而逐渐降低。供硫不足时,小麦硫的吸收量显著降低,在拔节至抽穗期吸收量很低,而在其前后出现２个高峰。小麦吸收到体内的硫达到一定浓度后,即使增加土壤硫的供给,植株硫的吸收过程也不会增强。如果土壤缺氮,即使供硫充足,植株也会缺硫。硫在小麦各器官的分配随生育期变化,供硫充足的小麦叶片的硫浓度保持最高,但叶片中硫的分配比例只在抽穗前最高,成熟过程中叶片中有部分硫运出。抽穗后茎的累积量迅速上升,分配比例最高。

Study on the Characteristics of Sulfur Nutrition of Winter Wheat

Effect of sulfur on winter wheat was studied in microplot experiment.The results showed that the concentration of sulfur in wheat plant decreased sharply after the peak value at reviving stage.Velocity of sulfur uptaking reached the highest value at booting to earring stage for S sufficient wheat plants,while there appeared two peaks for S deficient wheat induced by nitrogen insufficiency.The total amount of sulfur absorbed,and especially that at booting to earring stage,was far lower for S deficient plants than sufficient ones.Sulfur concentration,velocity of acquiring,and amount of absorption didn't increase even if additional sulfur was applied,once sulfur in soil was sufficient.However,sulfur deficiency was observed in sulfur sufficient soil owing to nitrogen deficiency.The concentration and amount of sulfur in organs varied with development of winter wheat. Leaves always had highest S content in S sufficient plants.But proportion of S in leaves decrease steadily.A part of S in leaves was transported out after earring.The amount and proportion of S in stem increased dramatically after earring.