机构地区: 中国科学院华南植物研究所
出 处: 《植物研究》 2003年第3期290-295,共6页
摘 要: 茸毛赤种子自花后 30d发育至 5 5d ,发芽率、发芽指数和活力指数由 0升至最大 ;含水量逐渐下降 ,但下降速率不等 ,发育后期存在显著的成熟脱水期。花后 45d果实干重接近最大 ,种子干重在 45d达到最大 ,种子和果实的发育基本同步。自然风干 1d后 ,花后 40~ 5 0d的种子含水量下降 2 %~ 4%。花后 40d的种子发芽力显著提高 ,花后 45~ 5 0d的种子无明显变化 ,继续干燥 ,发芽率、发芽指数和活力指数均有不同程度的降低 ,而花后 5 0d的种子直到含水量低至 4%后才明显下降 ;花后 35d和 5 5d的种子经过不同天数干燥后 ,发芽力均下降。不同发育时期茸毛赤种子耐脱水力有差别 ,由强至弱依次为花后 5 0、45、5 5、40、35d。用半致死含水量可准确地反映不同发育时期茸毛赤种子的脱水敏感性的强弱。 Seed germination percentage, germination index and vigor index of Thladiantha cordifolia(Bl.) Cogn.var.tomentosa A.M.Lu et Z.Y.Zhang rose from zero to maximum value following with the seed developing time from 30 DAA(days after anthesis)to 50 DAA. During this period, the seed MC(moisture content) decreased gradually with different rates. Seed dry weight approached the maximum value and a significant dehydrating stage appeared at 45 DAA shown that they were in a physiological maturing process. When drying the seeds of 40~50 DAA with their moisture content slightly decreased by 2~4% after natural air-drying for one day, the germination capacity of seeds at 40 DAA was improved significantly and that of the seeds at 45~50 DAA had no obvious changes. The germination percentage, germination index and vigor index decreased to various degrees when desiccation kept on. However, germination capacity of 50 DAA seeds appeared no significant change until the moisture content decreased lower than 4%. These results shown that the desiccation-tolerance of seeds were gradually formed and changed during developing process, an order of desiccation-tolerance from maximum to minimum of Thladiantha cordifolia var. tomentosa seed at different developmental stages were 50, 45, 55, 40 and 35 DAA. The Semilethal moisture content could indicate desiccation-sensitivity of Thladiantha cordifolia var. tomentosa seed at various developmental stages.
关 键 词: 种子 发育时期 脱水耐性 发芽力 茸毛赤瓞 葫芦科
领 域: [生物学]