采用田间试验法,研究了不同浓度及不同时期喷施叶面硒肥对春小麦硒素吸收、转化分配规律及硒肥利用率的影响.结果表明:(1) 在拔节期和孕穗期2次喷施10~20 mg/kg或孕穗期1次喷施40~50 mg/kg的亚硒酸钠溶液,都能使春小麦达到富硒标准.(2) 在拔节、孕穗、乳熟期喷施40 mg/kg亚硒酸钠溶液都能使籽粒中的硒素含量达到富硒标准,孕穗至乳熟期为最佳喷施时期.(3) 在生育进程中,全株硒素含量在0.062~0.187 mg/kg之间变化,平均0.086 mg/kg.叶面硒肥能显著提高各器官硒素含量,且富集效应顺序是叶>籽粒>颖壳>茎.(4) 全株硒素吸收量和吸收速率动态变化可分别用一元三次方程式和一元二次方程式定量表达.孕穗期喷施40 mg/kg亚硒酸钠溶液时,全株硒素最快吸收速率为0.0305 μg/(d·株),与对照相比,提高了9.5倍,出现时间提前4 d.%Field experiment was conducted to study the effects of selenium (Se) fertilizer on Se-enrich reaction and Se absorp-tion, distribution of spring wheat. The results showed: (1) To reach the standard of Se-enrich in spring wheat grain, appropri-ate foliar spray concentration of Se fertilizer was 10~20 mg/kg at jointing stage and booting stage, respectively; it was 40~50 mg/kg at booting stage. (2) With foliar spray of Se fertilizer in three spray period (jointing stage, booting stage and mil-king stage) treatments, the Se content in grain all reached the standard of Se-enrich, the appropriate period was from boo-ting stage to milking stage. (3) The change of Se content of the whole plant was 0.062~0.187 mg/kg in the growth period of spring wheat, with average of 0.086 mg/kg. The Se content in all organs of spring wheat could be improved effectively by foliar spray of Se fertilizer. Se accumulation of different organs was leaf>grain>shell>stem. (4) Se content and absorp-tion velocity in whole plant were calculated by cubic curve and quadratic cubic, respectively. The fastest absorption velocity was 0.030 5 μg/(d·plant) and could be improved by 9.5 times, 4 days earlier compared with the CK treatment.
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