柑桔同源及异源四倍体花粉育性研究

对８个柑桔同源四倍体及通过原生质体融合得到的２个异源四倍体的花粉育性和花粉粒大小进行了测定。结果显示，同源四倍体柑桔花粉育性平均为３６％，约为二倍体（６２％）的６０％。‘伏今夏’甜橙由于是异质结合的染色体易位突变体，其同源四倍体花粉育性比二倍体（２３％）高出５０％。权（Ｐｏｎｃｉｒｕｓｔｒｉｆｏｌｉａｔａ）与甜橙（Ｃｉｔｒｕｓｓｉｎｅｎｓｉｓ）属间以及来檬（Ｃ．ａｕｒａｎｔｉｆｏｌｉａ）与甜橙种间四倍体体细胞杂种花粉育性介于其双亲之间，花粉育性分别为各自高值亲本的９９％和７５％。同源及异源四倍体花粉粒体积平均为二倍体的２倍或双亲之和。本结果说明，柑桔体细胞杂种可作为杂交亲本进一步被利用。

Pollen Fertility of Auto-and Allo-tetraploids of Citrus

The fertility and pollen size of 8 citrus autotetraploids and 2 allotetraploid somatic hybrids were observed. The results showed that the average pollen fertility of autotetraploid plants was 36%, which was 60% of that of the corresponding diploid plants. However, the pollen fertility of 4x'Valencia'sweet orange was 50% higher than its 2x plants, since this variety is a hetero-translocation mutant. Intergeneric somatic hybrid of Poncirus trifoliata with Citrus sinensis cv. Valencia sweet orange and interspecific one of C. aurantifolia with Valencia sweet orange were fertile, with an intermediate pollen viability between the corresponding parents. The intergeneric one has 90% pollen fertility, and the interspecific one 38%. The average pollen volume of tetraploid plants was about twice the she of the diploids or the addition of both parents. The result also indicated that the allotetraploid somatic hybrids could be used as parents in future crossing.