荔枝种子发育过程中有机营养变化与萌发的关系

本文对比分析了‘紫娘喜’和‘妃子笑’2个荔枝品种种子发育过程中的种子萌发规律,研究了淀粉、可溶性糖、有机酸和氨基酸组分及含量变化,探讨了种子萌发与这些有机营养之间的相关性。结果表明,随着果实发育成熟,‘妃子笑’荔枝种子的萌发呈先上升后下降的趋势,‘紫娘喜’荔枝种子萌发率持续上升。盛花后45 d开始,‘紫娘喜’荔枝种子萌发率持续高于‘妃子笑’荔枝。果实发育过程中,‘妃子笑’和‘紫娘喜’荔枝种子的总可溶性糖含量分别呈“N”型和“W”型变化,二者的淀粉含量均逐渐升高;果实完全成熟时,‘紫娘喜’荔枝种子的淀粉含量显著高于‘妃子笑’荔枝。随着果实发育成熟,二者种子中的总有机酸含量均持续下降,但组分不同：‘妃子笑’荔枝种子中含有8种有机酸,‘紫娘喜’荔枝种子多了乳酸和琥珀酸;两个品种种子均含21种氨基酸,‘妃子笑’荔枝种子的总氨基酸含量呈现先降低后上升至稳定水平的趋势;而‘紫娘喜’种子中总氨基酸含量呈现先短时降低后升高再降低的变化。相关性分析表明,两个荔枝品种的种子萌发率与淀粉含量呈极显著正相关关系,与总有机酸含量呈极显著负相关关系。淀粉和有机酸可能是影响种子发育与萌发的主要有机营养物质。

Study on the relationship between organic nutrition changes and germination of litchi (Litchi chinensis Sonn.) seed during its development

The seed germination rules of two litchi varieties ''Ziniangxi'' and ''Feizixiao'' during seed development were compared and analyzed in this paper, and the components and contents variation of starch, soluble sugar, organic acid, and amino acid were studied. Then the correlation between seed germination and these organic nutrients was discussed. The results showed that with fruit development and mature, the germination rate of the ''Feizixiao'' seed increased first and then decreased; and the ''Ziniangxi'' seed continued to increase to a plateau. The seed germination rate of ''Ziniangxi'' was higher than that of ''Feizixiao'' 45 days after flowering (45 DAF). During fruit development, the total soluble sugar content of ''Feizixiao'' and ''Ziniangxi'' litchi seeds showed "N" and "W" type changes, respectively, and the starch content of both increased gradually. When the fruit matured, the starch content of ''Ziniangxi'' seeds was significantly higher than that of ''Feizixiao''. The total organic acid content of the seeds of the two varieties decreased continuously, but the components were different: ''Feizixiao'' seed had 8 kinds of organic acids, and ''Ziniangxi'' seed had more lactic acid and succinic acid. The seeds of both varieties contain 21 kinds of amino acids. The total amino acid content of ''Feizixiao'' decreased first, and then rised to a stable level after 38 DAF; however, that in the ''Ziniangxi'' seed decreased for a short time, then increased and then decreased. The correlation analysis showed that the seed germination rate of the two litchi varieties had a very significant positive correlation with starch content and a very significant negative correlation with total organic acid content. Starch and organic acids may be the main organic nutrients affecting seed development and germination.