甘肃省野生草地早熟禾多胚苗发生研究

以甘肃安定、清水、陇西、西和、秦州5个地区收集的野生草地早熟禾种质材料和商用品种巴润为试材,比较发芽率及多胚苗的发生率,分析了多胚苗的出苗类型,多胚的形成,多胚苗发生的影响因素。结果表明：不同品种和来源的草地早熟禾多胚苗发生频率差异很大,其中,双胚苗发生频率从高到低依次为巴润,14.2%;清水,12.9%;陇西,9.6%;定西,8.9%;陇南,7.2%。三胚苗发生频率从高到低依次为陇西,0.98%;秦州,0.34%;清水,0.28%;定西,0.20%;巴润,0.10%;陇南野生草地早熟禾中未发现三胚苗。通过种子萌发的苗数可将草地早熟禾多胚苗分为3种类型：正常单苗,双苗和三苗;双苗种子又包括簇生双苗、对生双苗、间生双苗3种情况,簇生双苗在双苗中发生频率高;三苗种子又包括对生三苗、簇生三苗,三苗发生频率极低,还不到百分之一。多胚苗的发生涉及多胚的形成和多胚苗的表现两大阶段,多胚的形成不仅受到遗传背景的影响,还受到外界条件的影响。

Research on embryo development characteristics in Gansu wild Poa pratensis

Five varieties of Gansu wild Poa pratensis and commercial Baron as trial material to analysis ger mination and poly-embryo rate. The influencing factors of poly-embryo formed and the mechansim of poly-em bryo seedling was studied as well. The results indicated that the occurrence frequency of difference varieties of leek was much difference on the basic of consistent germination rate. Among them double-embryo seedlings occurrence frequency were Baron, 14. 2% ; Qingshui, 12.9%; Longxi, 9. 6% ; Longnan, 7. 2%. Among them poly embryo seedlings occurrence frequency were Longxi, 0. 98%; Qingzhou, 0. 4%; Qingshui, 0. 28%;Dingxi, 0. types, two embryony seedlings opposite, fasciation and next,the frenquency of faseiated embryony seedlings occurrenced highest. Three embryony seedlings had three types, three embryony seedlings opposite, fasciation and next,the frenquency of three embryony seedlings occurrenced infrequent, lower than hundredth. The performance of polyembryony seedlings involved polyembryo formation and polyembryo seedlings germination,the formation of polyembryo not only influenced by genetic background, polyembryony seedlings germinated also influenced by external conditions.