Study on the relationship between changes of organic nutrition during seed develop-ment and seeds germination in litchi(Litchi chinensis Sonn.)
The characteristics of seed germination during seed development in two litchi varieties,Ziniangxi and Feizixiao were compared and analyzed,and the variations on components and contents of starch,soluble sugars,organic acid,and amino acid were studied.The correlations between seed germination and these pa-rameters were discussed.The results showed that with fruit development and maturing,the seed germination rate of Feizixiao increased first and then decreased,while that of Ziniangxi continued to increase.The seed ger-mination rate of Ziniangxi was always higher than that of Feizixiao from 45 days after flowering(45 DAF).During fruit development,the total soluble sugar content in the seeds of Feizixiao and Ziniangxi litchi showed N-and W-type change,respectively,and the starch content of both seeds increased gradually.When the fruit matured,the starch content of Ziniangxi seeds was significantly higher than that of Feizixiao seeds.The total organic acid content in the seeds of the two varieties decreased continuously,but varied in components.There were 8 kinds of organic acids in Feizixiao seeds,and Ziniangxi seed had extra lactic acid and succinic acid.There were 21 kinds of amino acids in the seeds of both varieties.The total amino acid content in Feizixiao seeds decreased first,and then increased to a stable level.However,the total amino acid content in Ziniangxi seeds decreased for a short time,and increased and then decreased.The correlation analysis showed that the seed germination rate of the two litchi varieties had extremely significant positive correlation with starch con-tent and extremely significant negative correlation with total organic acid content.Starch and organic acids may be the main organic nutrients affecting seed development and germination.