假色槭种子透水性及内源抑制物质的初步研究

Effects of Seed Permeability and Endogenesis Inhibitory Substances of Acerpseudo-sieboldianum Seeds

为研究假色槭种子透水性及种子不同部位甲醇浸提液生物活性,初步探讨假色槭种子休眠原因,比较了假色槭完整种子和剪裂种皮种子的吸水率,测定了种子各部位浸提液对小麦种子萌发及幼苗生长的抑制强度。结果表明,种皮透水性良好,对假色槭种子休眠影响较小。假色槭种子的果皮、种皮、胚浸提液处理后,对小麦种子发芽率影响较小,但却严重影响了小麦苗高、苗鲜重、根长、根鲜重的生长,降低了叶绿素含量、淀粉酶活性,抑制了小麦种子对自身淀粉和可溶性糖的吸收利用,而且随着各部位浸提液浓度比例的不断提升,其抑制活性也表现得愈加强烈。在各部位浸提液浓度比例相同的情况下,胚浸提液对小麦种子发芽率、苗高、苗鲜重、根长、根鲜重的生长以及各项生理指标的抑制影响强于种皮和果皮。说明假色槭种子果皮透水性不是其休眠的主要原因,种子各部位存在发芽抑制成分,尤其是胚的抑制活性最强可能是其休眠期较长、不易发芽的主要原因。

In order to study the dormancy mechanism of Acerpseudo-sieboldianum seeds, seed permeability and inhibitory activity of endogensic inhibitory substances of Acerpseudo-sieboldianum were investigated in this paper. The water permeability between intact seed and piercing naked seed were compared, and the inhibitory activities of the methanol extracts from the pericarp, seed coat and embryo of Acerpseudo- sieboldianum against seed germination and seedling growth of wheat were also studied. The results showed that the permeability of the seed coat was good. The different concentration of methanol extracts from different parts of seeds had an inhibiting effect on plant height, fresh seedling weight, root length and fresh root weight of wheat, which decreased the content of chlorophyll content and the activity of tr-amylase and inhibited in metabolizing of the starch and soluble sugar. As the concentration increased, the inhibition enhanced. In the same concentrations, the extracts from the seed embryo could inhibit wheat germination and growth at higher level than that from the pericarp and the seed coat. It was concluded that the permeability of the seed coat to water was not the main cause of seed dormancy of Acerpseudo-sieboldianum. The inhibitors were distributed in all fractions of the seeds, mainly embryo. It might be the main reason of Acerpseudo-sieboldianum long period dormancy.