叶面喷施硒肥对南瓜果实硒含量、产量及营养品质的影响

Effects of foliar spraying selenium solution on selenium content,yield and nutrition quality of pumpkin fruit

通过研究不同时期叶面喷施硒肥对南瓜果实硒含量、产量及营养品质的影响,明确南瓜最适喷施时期和施硒浓度,以期为富硒南瓜生产提供最佳富硒方案和理论依据。以南瓜品种橄榄贝贝2号为试材,亚硒酸钠为硒源,设置3个喷施时期(伸蔓期+雌花期、伸蔓期+膨果期、雌花期+膨果期)和4个浓度水平(0、207、321和723μmol·L^(-1))的叶面喷施试验。结果表明,与CK相比,喷施硒肥后,果实硒含量显著提高,随硒液浓度的增加而升高,且全部为有机硒;相同浓度处理的果实硒含量“雌花期+膨果期”>“伸蔓期+膨果期”>“伸蔓期+雌花期”。叶面喷施硒肥不仅可以提高单果质量,而且不同程度地提高了果肉中β-胡萝卜素、维生素C、淀粉、可溶性蛋白、可溶性固形物和可溶性糖的含量,但对氨基酸含量无显著影响;对南瓜果实矿质元素含量的影响主要表现在对Pb、Cd的富集有抑制作用,显著提高Fe、K的含量,适宜浓度硒肥处理显著降低Zn、Cu含量,对Na、Mg、Ca含量没有影响。通过回归方程计算得出在雌花期和膨果期各喷施一次1~197μmol·L-1亚硒酸钠溶液,果实硒含量符合富硒标准。

In order to provide the best selenium enrichment scheme and theoretical basis for the safe production of selenium rich pumpkins,the optimal spraying period and concentration were determined by studying the effects of foliar spraying selenium solution at different stages on the selenium content,yield,quality and mineral element content of the pumpkin fruits.In this paper,Olive Beibei No.2 was used as the test material and the sodium selenite as the selenium source.Three spraying periods(vines stage+female flowering stage,vines stage+fruit expansion stage,female flowering stage+fruit expansion stage)and four concentration levels(0,207,321 and 723μmol·L^(-1))were set up in the experiment of foliar spraying selenium solution.The results showed that after spraying selenium fertilizer,the selenium content of pumpkin fruits compared with CK increased significantly with the increase of selenium solution concentration and the seleniums in pumpkin fruits were all organic.The selenium contents of pumpkin fruits which treated with the same concentration were"female flowering stage+fruit expansion stage">"vines stage+fruit expansion stage">"vines stage+female flowering stage".It was found that spraying selenium solution on pumpkins leaves not only could improve the quality of individual fruits,but also could increase the content of carotene,vitamin C,starch,soluble protein,soluble solids and soluble sugar in pumpkin fruits at different degrees.But there was no significant impact on amino acid content after spraying selenium solution.The impact of spraying selenium solution on the mineral element content of pumpkin fruit manifested in the inhibitory effect on the enrichment of Pb and Cd and the significant increase of the content of Fe and K.The content of Zn and Cu is significantly reduced after applying an appropriate concentration of selenium solution,but the Na,Mg,and Ca content had no change.By regression equations,the selenium content of pumpkin fruits met the selenium enrichment standard after spraying sodium selenite solution at 1-197μmol·L-1 once in the female flowering stage and fruit expansion stage respectively.