小芸木胚发育过程中脱水耐性的变化

对热带植物小芸木的种子和胚在整个发育阶段的形态学特征、含水量、萌发率和电导率进行了研究。结果显示:(1)小芸木种子在发育过程中形态学特征、电导率、萌发率和胚的脱水耐性有明显的变化;(2)在55~80 d种子鲜重和干重逐渐增加,随后又稍微降低,整个发育过程未经历明显的成熟脱水阶段;种子萌发率从55~85 d逐渐达到最大,随后又稍微降低;(3)胚的脱水耐性从55~90 d逐渐增加,于85~90 d达到最大,在95~103 d时又有所下降。表明小芸木胚的最大脱水耐性的获得时间与种子干物质积累达到最大的时间一致。

Changes in Desiccation Tolerance of Micromelum integerrimum Roem. Embryos during Its Development

This paper describes research results on some morphological properties, moisture content, germinability,leakage rate of electrolyte and desiccation tolerance of Micromelum integerrimum Roem. seeds at various developmental stages. It showed that throughout the course of development M. integerrimum seeds experienced significant changes in morphological characteristics, leachate conductivity, germinability and desiccation-tolerance. Between 55 to 80 days after flowering (DAF),both fresh and dry weight of seeds increased gradually. Seed germinability gradually reached up to a maximum from 55 to 85 d, but decreased somewhat thereafter. During 55 to 90 d,embryos desiccation tolerance increased and reached a maximum at 85 ～90 d, but decreased at 95 ～ 103 d. It didn' t experienced obviously maturation dehydration. The acquisition of the maximum desiccation tolerance of embryos takes place on 90 d which conform to the maximum dry matter accumulation.