同源四倍体水稻与非洲栽培稻杂交的后效性研究

利用亚洲栽培稻中的4份同源四倍体水稻(O.sativa,2n=4x=48)和相应的4份二倍体水稻(O.sativa,2n=2x=24)为母本,以4份非洲栽培稻(O.glaberrima,2n=2x=24)为花粉供体进行远缘杂交后,对其杂种后代的分离动态进行了研究.结果表明,不同倍性的普通栽培稻与非洲栽培稻之间杂交后代的结实率以二倍体普通栽培稻的较高.在配制的32个杂交组合中,其杂种第1代群体均表现出明显的营养生长优势.从群体的生长势来看,杂种第2代群体比杂种第1代群体要弱一些;在杂种第2代群体中,以同源四倍体水稻为母本的杂交组合的分离现象比以二倍体水稻为母本的杂交组合的分离现象更明显.在各杂交组合的第3代群体中,从植株的株叶形态和生育期来看,株系间的差异和株系内的变异依然很明显,变异频率更宽,变异种类更多.在普通栽培稻与非洲栽培稻的杂交组合中,育性变异、生长势变异、株叶形态变异、染色体变异和结实性变异等是较易发现的变异现象.

Effects in the Posterities of Distant Hybridization between Autotetraploid Rice (O. sativa) and African Rice (O. glaberrima)

Using 4 autotetraploid rice lines and their corresponding diploid rice lines (O.sativa) as the female and 4 African rice lines as the male to make crosses, the effects in the posterities of distant hybridization between autotetraploid rice (O.sativa) and African rice (O.glaberrima) were studied. The results showed that the seed set of the progenies from the hybridization between diploid rice and African rice was higher than that between autotetraploid rice and African rice. The F_1 hybrids from the 32 distant crosses showed obvious heterosis in vegetative growth. The population growth rate was weaker in the F_2 progenies than in the F_1 progenies. The segregation in the F_2 generations was greater in the crosses using autotetraploid rice as the female than those using the diploid rice as the female. In terms of plant type and growth period, the variation among different lines and individual plants within the same lines was still remarkable in the F_3 generations. The variants were easily found in male sterility, growth rate, plant type, number of chromosomes and seed setting percentage in the progenies of the distant hybridization.