烟草耐黄瓜花叶病品系GAT-2 GAT-4的研究与利用

STUDY ON UTILIZATION OF TOBACCO BREEDING STRAINS GAT-2 AND GAT-4 WITH CMV-TOLERANCE

1982～1988年对GAT-2、GAT-4的研究结果表明,此两品系高抗烟草普通花叶病,也是目前耐黄瓜花叶病性能较强的品系。运用回交育种法转移它们五对耐病基因的关键是F_2和各回交世代的F_2,必须选择具五对耐病基因的植株与轮回亲本回交,以及各回交世代必须保持极大的接种群体。具五对耐病基因植株的选择标志是:幼苗接种TMV后,拔除N—type枯斑株及系统感染株,剩余幼苗再接种CMV,无病症株即为具五对耐病基因之植株。

Observations from 1982 to 1988 showed that two tobacco breeding strains, GAT-2and GAT-4, were resistant strongly to tobacco TMV disease, and more tolerant to CMVdisease. When backcross technique was used to transfer their 5 pairs of CMV-tolerantgenes, two significant points should be emphasized. In the populations of their F_2 andthe F_2 from every backcross generations, the plants with 5 pairs of CMV-tolerant genesshould be picked out and hybridized back to the recurrent parent. During inoculationexaminating, a considerably great number of inoculum populations should be applied. Thesymbolizations for selecting plants with 5 pairs of CMV-tolerant genes were as follows: af-ter seedlings were inoculated with TMV, those plants which showed N-type necroses orsystematic infection were removed. The rest were reinoculated with CMV and thensymptomless plants were those with 5 pairs of CM V-tolerant genes.