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本文从DNA、RNA、蛋白质和类脂等大分子物质的含量变化以及凝集素类物质的存在等方面,探讨了杉木种子和胚胎发育的生化变化。1.种胚在7～8月正处于分化发育旺期,干重显著增加,胚的大小增长迅速,平均长度此时增长最快,从7月至8月平均增长7.4倍。2.种子的核酸总量也以7～8月增加最快(增加2倍)。DNA的含量也在7～8月增加最快(增加3倍多),而后趋平缓。RNA含量的变化与DNA的变化大致相似,在7～8月增加近2倍,较显著。3.在DNA、RNA含量增加的同时,种子内蛋白质、类脂的含量均相应增加。7～8月间,蛋白质含量从108.19微克/粒增至662.30微克/粒(增加5倍多),种子成熟时为1760.45微克/粒。类脂含量一直持续增加,到种子成熟时达2.04毫克/粒种子。4.种胚干重从7月的分化期到成熟期持续增加,8月为0.33毫克/胚,到成熟时为1.00毫克/胚(增加2倍)。核酸总量随胚发育而增加,成熟时达12.58微克/胚。DNA和RNA含量也随胚发育而逐渐增加,到胚分化完全后的10月下旬,含量达到高峰,DNA为3.48微克/胚,RNA为9.10微克/胚。蛋白质和类脂也如此,达高峰时蛋白质为455.57微克/胚,类脂为0.47毫克/胚。但以种子中每毫克粒干重和胚干重为单位的DNA和RNA的含量却随种子的发育和胚的分化而减少,蛋白质含量仍增加,至成熟后才下降。这可能由于细胞内含物和结构物质的增加所致。从胚珠提取液的凝血活性测定的结果表明,杉木在授粉前的胚珠中就存在凝集素类物质,且活性相当高。同样在胚胎发育过程中,胚和雌配子体(胚乳)中都发现凝集素类物质的存在,其凝血活性随胚发育而增加,但胚乳中则仅在前期存在凝集素类物质。
In this paper, the biochemical changes of seed and embryo development of Chinese fir (Cunninghamia lanceolata) were studied in terms of the content changes of macromolecules such as DNA, RNA, proteins and lipids and the existence of lectins. 1. Embryos in the period from July to August is in the period of differentiation and development, dry weight increased significantly, the size of the embryo increased rapidly, the average length of the fastest growing at this time, an average increase of 7.4 times from July to August. 2. The total amount of seed nucleic acid also increased in July to August the fastest (2-fold increase). DNA content also increased fastest in July-August (more than three times more), and then flatten. Changes in RNA content and DNA changes roughly similar in July and August increased nearly 2-fold, more significant. In the DNA, RNA content increased at the same time, the seeds of protein, lipid content increased accordingly. From July to August, the protein content increased from 108.19 μg / grain to 662.30 μg / grain (a 5-fold increase), with 1760.45 μg / grain at maturity. Lipid content continued to increase until seeds reached 2.04 mg / seed. 4. Embryonic dry weight continued to increase from the differentiation to maturity in July, 0.33 mg / embryo in August, and 1.00 mg / embryo (2-fold increase) at maturity. The total amount of nucleic acids increases with embryo development, reaching 12.58 μg / embryo at maturity. The content of DNA and RNA also increased gradually with embryo development. After the embryo was completely differentiated, the content of DNA and RNA peaked in late October, with 3.48 μg DNA / embryo and 9.10 μg RNA RNA. The same is true for proteins and lipids, reaching a peak of 455.57 micrograms / embryo and a lipid of 0.47 micrograms / embryo. However, the content of DNA and RNA per dry weight and embryo weight per milligram of seeds decreased with seed development and embryo differentiation, and the protein content still increased until it decreased after maturation. This may be due to the increase of cellular inclusions and structural substances. The results of the coagulation activity assay from the ovule extract showed that the Chinese fir had lectins present in the ovules before pollination, and the activity was quite high. Also in the process of embryonic development, the presence of lectins is found in embryos and female gametophytes (endosperm), and its coagulation activity increases with embryo development, but in the endosperm, only the pre-lectin-like substances exist.