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二倍体和四倍体多花黑麦草×苇状羊茅杂种 F_1 花粉母细胞减数分裂染色体具有较高的配对水平,单价体少,二价体多。存在低频率的三价体、四价体和较低频率的五价体,表明多花黑麦草和苇状羊茅染色体之间存在同源或部分同源和异源苏会配对,F_1 正常花粉频率平均为0～18.2%,不同杂交组合甚至同一组合不同植株均有很大的差异。F_1 的回交结实率很低,平均为0.05粒种子/小穗,且易与多花黑麦草回交。杂种后代自交结实率与其亲本一样均很低。开放授粉结实率则随着世代的增加显著提高,F_1 代平均仪为0.4%,至第五代高达65.5%。杂种后代越夏性以 F_1为最强,平均达79.9%,介于双亲之间或与苇状羊茅相近,随着世代的增加越夏性则逐渐丧失。推测越夏性丧失与杂种后代群体过早或过多地丢失苇状羊茅染色体,减少了优良基因重组的机会有关。育性正常、越夏性较强的黑麦草型第四代选系“891”的获得,表明把苇状羊茅的越夏性部分地转移到多花黑麦草中是可行的。
The chromosomes of diploid and tetraploid ryegrass × Fescue fescue hybrid F_1 pollen mother cells had higher pairing level, fewer monovalent bodies and more bivalent bodies. The existence of low-frequency trivalent, tetravalent and lower-frequency pentavalents indicates that homologous or partially homologous and heterologous Su-paired pairs exist between the chromosomes of the ryegrass and the tall fescue, F 1 normal pollen The average frequency ranged from 0 to 18.2%. Different crosses or even different combinations of the same genotypes showed significant differences. F_1 had a very low rate of backcrossing with an average of 0.05 seeds / spikelet and was easily backcrossed with ryegrass. Hybrid selfed seed set rate as low as their parents. However, the rate of open pollination and seed setting increased significantly with the increase of generations, with average F 1 generation of 0.4% and up to 65.5% of the fifth generation. The more heterosexual offspring F_1 was the strongest, with an average of 79.9%, which was similar between parents or with tall fescue. With the increase of generations, the more the summer was, the more lost. It is speculated that the loss of summer sex is related to the premature or excessive loss of the chromosomes of F. fescue by the offspring population, reducing the chance of good gene recombination. Fertility, summer and more strong rye grass type fourth generation “891” access, indicating that the more part of the summer fescue Festuca transfer to ryegrass is feasible.