大鸭梨与不同倍性梨品种杂交后代染色体数目鉴定

Observation on Chromosome Number of Hybrid Progeny of Dayali and Pear Cultivars with Different Ploidy

本文用去壁低渗－火焰干燥－Ｇｉｅｍｓａ染色法对大鸭梨与不同倍性梨品种杂交后代的染色体数目进行了鉴定，共１０个组合３８１株，发现 ３０株为三倍体（２ ｎ＝３ ｘ＝５１），其中，１株为金花４号×大鸭梨的后代，８株为大鸭梨×金花４号的后代，３株为大鸭梨×秦酥的后代，６株为大水核×大鸭梨的后代，８株为安梨×大鸭梨的后代，２株为大鸭梨×安梨的后代，２株为白皮洋×大鸭梨的后代，三倍体的比例为 １．９％；６８株为四倍体（２ｎ＝４ｘ＝６８），其中１株为大鸭梨×安梨的后代，１株为安梨×大鸭梨的后代，１株为大水核Ｘ大鸭梨的后代，２１株为沙０１×大鸭梨的后代，４４株为大鸭梨×沙０１的后代，四倍体的比例为１７．８％；１２株为非整倍体，占观察总数的３．１％；余者为二倍体。结果表明，大鸭梨为倍性育种的优异种质资源。

Observations on chromosome number of 381 seedlings derived from 10 crossings of tetraploid pear cultivar 'Dayali'as seed or pollen parent with pear cultivars with different ploidy were made and it was found that 30 seedlings, including 1 seedling from Jinhua 4 × Dayali, 8 from Dayali × Jinhua 4, 3 from Dayali × Qinsu, 6 from Dashuihe × Dayali, 8 from Anti × Dayali, 2 from Dayali × Anti, 2 from Baipiyang × Dayali, were triploid (2 n ＝3 x＝ 51) and the frequency of triploid was 7. 9 %; 68 seedlings, including 1 seedling from Dayali × Anti, 21 from Sha 01 × Dayali, 44 from Dayali × Sha 01, 1 from Anti × Dayali, 1 from Dashui- he × Dayali, were tetraploid(2 n ＝4 x＝ 68)and the ratio of tetraploid produced was 17. 8 % ;12 seedlings were aneuploid and the ratio of aneuploid produced was 3.1 %; remaining seedlings were diploid. The re- sults showed that Dayali pear is an excellent germplasm resource for pear polyploid breeding.