普通小麦与华山新麦草的杂交

The Hybridization Between Triticum aestivum and Psathyrostachys huashanica

华山新麦草是分布在秦岭山脉华山段的1个特有种,经细胞学鉴定为二倍体种(2n=14)。利用普通小麦与之杂交并通过幼胚培养获得了杂种,杂交结实率为0.19%,幼胚培养出苗率为33.3%。杂种表现为双亲的中间型,杂种F_1体细胞染色体数为2n=28,花粉母细胞减数分裂中期Ⅰ每细胞平均0.99个二价体,26.01个单价体。杂种花粉粒败育,以小麦花粉与杂种回交时获得了种子,回交结实率为2.5%。回交一代体细胞染色体数为2n=49,花粉母细胞减数分裂中期Ⅰ染色体构型多数为2Ⅲ+7Ⅰ。

Psathyrostachys huashanica Keng. is a special diploid species and distributed in Huashan branches of the Qinling mountain chain. It is very difficult to cross Triticum aestivum with P. huashanica. The hybrids have been obtained by means of embryo culture. The percentage of seed set of cross was 0.19% and germination rate of embryo culture was 33.3%. The F1 plant appeared to be intermediate between their parents in morphology. The chromosome number of F1 plant root tip cells was 2n = 28. The 0.9911 and 26.011 per cell of F1 plant were observed at PMC's Ml and the pollen grain were abortive. The percentage of backcross seed set of F1 hybrid pollinated with common wheat pollen was 2.5%. Root tip chromosome numbers of BC1 plants were 2n = 49 and most of the chromosome configuration at PMC's Ml of BC1 was 2111 + 71