摘要
通过远缘杂交,结合杂种幼胚培养,获得了普通栽培燕麦(0001,Avenasativa,2n=42,AACCDD)与野生大燕麦(0034,A.magna,2n=28,AACC),东方燕麦(0025,A.orientalis,2n=42,AACCDD)与野生大燕麦(0027,A.magna,2n=28,AACC)的杂种F1,其杂交结实率分别为8.00%和8.11%。对杂种F1花粉母细胞(PMC)减数分裂中期Ⅰ(MⅠ)染色体行为观察发现,“0001×0034”杂种F1平均每PMC有10.95个单价体,24.05条染色体发生联会形成二价体,平均每PMC染色体构型为2n=35=10.95Ⅰ+12.03Ⅱ(6.75rod+5.28ring)(Xta=17.35)。“0025×0027”杂种F1平均每PMC有8.43个单价体,26.60条染色体发生联会形成二价体和少数三价体,平均每PMC染色体构型为2n=35=8.43Ⅰ+13.22Ⅱ(8.00Ⅱrod+5.22Ⅱring)+0.054Ⅲ(Xta=18.73),表明六倍体燕麦的A、C染色体组与四倍体燕麦的A、C染色体组不完全同源,可能发生了一些结构性变异。
Oat belongs to genus Avena L. in Gramieae. Cultivated oat is a cereal crop available for human nutrition and health and animal feed. Basic researches of oat are weaker than other crops in genetics, physiology and biochemistry. The evolution of the tetraploid and hexaploid species is vague, and the origins of B, C and D genomes have not been identified. Germplasm of oat breeding in China is poor. The tetraploid oat is the important germplasm for oat breeding. At present, the researches on the cross between tetraploid and hexaploid species are very few. The objectives of this study were to expand the genetic resources by analysing the morphologic, cytogenetic characteristics and backcrosses seed setting rate of hybrids involving Avena sativa with A. magna and A. orientalis with A. magna. Hybrids of A. sativa （0001） × A. magna （0034） and A. orientalis （0025） × A. magna （0027） were successfully obtained by hybridization and immature embry on culture in vitro. Their seed setting rates were 8.00% and 8.11%, respectively （Table 2）. Morphologic characteristics of these hybrids F1 were intermediate between the parents or resembled either of parents （Table 3）. Pollen fertility of these hybrids F1 were 1.00% and 0.80%, respectively （Table 4）. Seed setting rates of hybrids in backcrosses were 1.97% and 1.75 %, respectively （Table 5）, indicating it can be feasible to transfer the beneficial genes from tetraploid species into hexploid A. sativa. At the same time, chromosomes pairing behaviors of the hybrids F1 at meiosis were investigated. There were 10.95 univalents in the pollen mother cell （PMC） in hybrid F1 of combination ‘0001 × 0034’ and 24.05 associated chromosomes formed bivalents on the average,their meiotic configuration was 2n = 35 = 10.95 Ⅰ ＋ 12.03 Ⅱ （6.75 rod ＋ 5.28 ring） （Xta = 17.35 （ Table 6, Plate Ⅰ 3 - 5）. For the F1 of combination ‘ 0025 × 0027’, 8.43 univalents, were observed in each PMC, 26.60 associated chromosomes formed bivalents and few trivalents, the meiotic configuration was 2n = 35 = 8.43 Ⅰ ＋ 13.22 Ⅱ （8.00 Ⅱ rod ＋ 5.22 Ⅱ ring） ＋ 0.054Ⅲ （Xta = 18.73） （Table 6, Plate Ⅰ 9 - 11） ,indicating the A, C genomes of the hexaploid and tetraploid were incompletely homologous.
出处
《作物学报》
CAS
CSCD
北大核心
2005年第9期1186-1191,i0005,共7页
Acta Agronomica Sinica
基金
国家"863"计划项目(2003AA207100)
中国科学院知识创新工程重要方向性项目(KSCX2-SW-304)
四川省作物育种攻关项目资助。
作者简介
邓光兵（1971-），男，苗族，重庆人，专业：遗传学。Tel：028．85232103；E-mail：denggb@cib.ac.cn
通讯作者：余懋群（1957-），男，四川人，博士，研究员，博士生导师，专业：植物遗传学。Tel：028-85229053；E-mail：：yumq@cib．ac．cn
