以异源四倍体体细胞杂种为父本杂交培育三倍体柑桔植株的研究

以 3个柑桔原生质体融合而来的四倍体体细胞杂种为父本 ,与二倍体单胚性种柚子 (Citrusgrandis)以及单多胚混合型品种“华农本地早”桔 (C.reticulata)有性杂交 ,授粉后 90 d,发现种子干瘪 ,大部分种子的胚败育。将干瘪种子在 MT附加 1mg/L GA3 或 50 0 mg/L麦芽浸出物的培养基中 ,经培养抢救 ,有 2 5.6%的种子萌发成苗或继续进行胚的生长 ,后者进一步诱导能形成丛芽 ,经试管嫁接或诱导生根形成完整植株。共获得 6个组合 73棵完整植株 ,染色体数检查表明 ,2 0株为三倍体 (2 n=3x=2 7) ,32株为二倍体 (2 n=2 x=18) ,8株为非整倍体 ,其它 13株还有待于进一步检查。

TRIPLOID CITRUS PLANTS OBTAINED FROM CROSSING THE DIPLOIDS WITH ALLOTETRAPLOID SOMATIC HYBRIDS

Hybridizing the diploid monoembryonic pummelo (Citrus grandis) and polyembryonic tangerine (C. reticulata cv. Huanongbendizao) with allotetraploid somatic hybrids from protoplast fusion were conducted. Seeds of pollinated fruits were found to be abortive 90 days after pollination. The aborted seeds were then cultured on media of MT supplement with 1 mg/L GA 3 or with 500 mg/L of malt extract. 25.6% of the seeds germinated or developed into embryoids. The entire plants were transplanted into soil after grafting shoots on the root stocks of trifoliate orange in vitro, if the germinated embryos have poor roots or no root at all. A total of 73 plants from 6 different combinations were obtained, among which 20 were verified as triploids with 2n=3x=27 chromosomes, 32 diploids 2n= 2x=18 , 8 aneuploids and the rest 13 unconfirmed.