芝麻种子萌发动态及其代谢生理变化研究

为明确芝麻种子萌发过程的代谢生理变化，丰富芝麻种子生物学内容，在25 ℃暗培养条件下，以2个芝麻品种为材料，研究了种子萌发0～72 h过程中的形态变化、水分吸收以及可溶性糖、可溶性蛋白、氨基酸、粗脂肪、游离脂肪酸和脂肪酶活性等代谢生理指标的变化。结果表明，芝麻种子在浸水后6 h吸胀，12 h萌动，24 h胚根开始快速伸长，48 h胚芽开始快速生长，72 h完成发芽。吸水率呈现不断上升的趋势，其中在 0～6 h和24～60 h 2个时间段表现为急速上升；吸水速 率呈现先降后升再降的变化过程，其中在0～3 h时下降最快，在胚芽开始生长（吸水后48 h）后再次出现较大幅度上升。随着萌发进程的推进，可溶性糖含量和可溶性蛋白含量均表现为先降后升趋势，氨基酸含量不断下降，粗脂肪含量在24 h后有所下降，游离脂肪酸含量呈现先降后升再降的变化趋势，脂肪酶活性不断增强，棕榈酸、硬脂酸、油酸和亚油酸等主要脂肪酸组成变化非常小。因此，芝麻种子萌发过程中，最先启动糖代谢，随后启动蛋白质和脂肪的代谢。研究结果为芝麻种子萌发机理进一步研究提供参考。

Germination Dynamics and Physiological Changes of Metabolism in Sesame Seed

In order to clarify the metabolic physiological changes of sesame seeds during germination and enrich seed biology of sesame seed, the germination of two sesame varieties was studied at 25 ℃ under dark condition. The changes of morphological changes, water absorption, soluble sugar content, soluble protein content, amino acid content, crude fat content, free fatty acid content and lipase activity during seed germination course of 0 ～ 72 h were tested. The results showed that sesame seeds started to expand at 6 h after soaking, protruded at 12 h, the radicle began to grow rapidly at 24 h, the germ began to grow rapidly at 48 h, and germinated 72 h later. Water absorption rate showed a rising trend, which showed a rapid increase during 0 ～ 6 h and 24 ～ 60 h. Water absorption speed showed a change process of first decreasing, then increasing and decreasing again, among which the fastest decline appeared at 0 ～ 3 h, and a large increase again after the embryo began to grow at 48 h after water absorption. With the development of seed germination, content of soluble sugar and protein decreased first and then increased; the content of amino acid decreased continuously, and the content of crude fat was after 24 h; the content of free fatty acids decreased first, then increased and decreased again; lipase activity increased continuously; and the composition of main fatty acids such as palmitic acid, stearic acid, oleic acid and linoleic acid changed very little. Therefore, during the process of seed germination, sugar metabolism initiated firstly, followed by protein and fat metabolism. The present research provided a reference for further study on seed germination mechanism of sesame.