马尾松种子发育过程中种仁贮藏物质的积累与变化

The Accumulation and Change Trend of Storage Substance of the Masson Pine′s Seed Kernels in It′s Developing Procedure

连续４ａ以不同发育阶段的马尾松种子为试材，研究其种仁贮藏物质的积累过程及其组分含量的变化规律。结果表明：（１）种仁的干重占成熟球果干重的４．８％。其贮藏物质随种胚发育而不断变化，粗脂肪、粗蛋白和总糖的最终含量分别为：４４．７６％、４２．５０％和７．１４％（其中淀粉和可溶性糖分别为４．２６％与２．８８％）。（２）酶蛋白的最大含量在原胚阶段初为２０．８３％，以后至幼胚阶段急剧减少到４．９％。（３）脂肪由４种脂肪酸组成，以不饱和酸含量最高（亚油酸为６５．７％，油酸２１．７％）；饱和酸中的棕榈酸和硬脂酸仅为９．２％和３．４％。（４）种仁的氨基酸主要有１６种，其中有１４种的最低含量出现在原胚阶段初；１０种的最高含量在幼胚阶段初。以精氨酸、谷氨酸和天冬氨酸３种含量高，达３．０６％～７．１３％；赖氨酸、酪氨酸、组氨酸、胱氨酸和蛋氨酸５种的含量低，在１．００％以下。

Seed kernels at various developmental stages were used as experimental materials to systematically study the accumulative procedure of storage substances and change trend of component contents.It was showed that the seed kernel accounts for 4.8% of dry weight of the ripen cone and its storage substances change with the embryo development. The contents of gross fat, gross protein and total carbonhydrate of ripen seed kernels are 44.8%,42.5% and 6.54% respectively,while starch and soluble carbonhydrate account for 4.26% and 2.88% respectively. Enzymic protein content decreases from the maximum at early phase of proembryo stage (20.83%) to the minimum at young embryo (4.9%). Here the fat of the seed kernels consists of four kinds of fatty acid,of which the content of unsaturated fatty acid is much more than each one of the saturated fatty acid. Lindeic,oleic,palmitic and stearic acid accounting for 65.7%,21.7%, 9.2% and 3.4% of the total fatty acid respectively.It was found that seed kernels of masson pine contain mainly 16 kinds of amino acid,of which the minimum content of the 14 kinds appears at the proembryo stage and the maximum content of the 10 kinds at the early phase of young embryo stage.Among 16 kinds of amino acid,the contents of arginine,glutamic and aspartic acid are higher (from 3.0% to 7.5%),and lysine,tyrosine,histidine,cystine and methionine the lower(<1%).