亚硒酸钠对甜荞生长的影响

Growth of Sweet Buckwheat in Response to Sodium Selenite

【目的】探究亚硒酸盐对甜荞生长的影响,提高甜荞产量和品质。【方法】通过随机区组盆栽试验,研究了5个不同质量浓度的亚硒酸钠对甜荞生长的影响。【结果】适量施用硒肥能够促进甜荞生长,当施用硒肥质量浓度在0~10 mg/kg时,可以促进甜荞叶绿素合成、提升蒸腾速率、气孔导度、净光合速率和甜荞生物量,超过10 mg/kg则会产生抑制作用。但甜荞根系和叶片叶绿素b不会受亚硒酸钠质量浓度影响。从甜荞整个生育期来看,在盛花期,硒肥对甜荞影响最显著,此外适量施用硒肥还可以减缓甜荞生长进程中叶绿素、蒸腾速率、气孔导度和净光合速率的下降程度,起到延缓甜荞衰老的作用。【结论】适量施用亚硒酸钠可以促进荞麦生长、延缓衰老进程,过度施用硒肥会抑制甜荞生长,但不会影响甜荞根系生长。

【Objective】Selenium is a minor plant nutrient and the objective of this work is to experimentally study the effects of selenium on growth,yield and quality of sweet buckwheat.【Method】The experiments were conducted in pots fertilized with sodium selenium.Fertilizer gradient consisted of five sodium selenium concentrations.The pots were randomly arranged and during the experiment,we measured the growth of the buckwheat in each pot.【Result】Synthesis of chlorophyll,transpiration rate,stomatal conductance,net photosynthetic rate and biomass of the buckwheat were all boosted when the selenium application was in 0~10 mg/kg(fertilizer/dry soil),but were inhibited when the application exceeded 10 mg/kg.During the whole growth season,selenium fertilizer was most effective in the blooming stage.It was also found that rationally applying selenium fertilizer can slow the decline of the synthesis of chlorophyll,transpiration rate,stomatal conductance and net photosynthetic rate,thereby delaying the aging of the buckwheat.【Conclusion】Applying an appropriate amount of sodium selenite can promote buckwheat growth and delay its aging process,however excessive application inhibited growth of the canopy but not the roots.