烟草抗病基因源的利用与抗病育种策略

抗源选择是抗病育种的关键。野生和种间抗源的利用是目前和今后较长时间内烟草抗病育种的重要途径。体细胞杂交和体细胞无性系变异不仅丰富了烟草抗源的变异来源,而且使这些抗源易于操作和利用。配子体单克隆系变异与加倍单倍体的产生程序,以单倍体作为育种选择单位的技术,不仅选育出了含有新的抗病种质的品种(系),而且改进了抗病育种方法、并改变了抗病育种策略。新的抗病基因变异源的利用,对抗病性和产量、品质性状的同时改良,是今后烟草抗病育种必须达到的目标。

GENETIC VARIATION SOURCES AND BREEDING STRATEGIES FOR DEVELOPING TOBACCOS WITH DISEASE RESISTANCE

The selection of genetic sources for disease resistance is suggested to be significantly important for plant breeding. The technology of somatic hybridization and somaclonal variation not on- ly enlarges the range of genetic variation for disease resistance in tobaccos, but also makes them easy to be handled in breeding process. Based on the gametoclonal variation and the procedure for doubling sporophyte haploid, the haploid sporophyte is tendencious to be used as selection unit in plant breeding. This improved method not only results in the production of new cultivars or lines of tobaccos, in which the new germplasms for disease resistance are introduced, but also causes the improvement in both breeding method and breeding strategy for developing tobaccos with disease resistance. For this improved strategy, the utilization of new sources of genetic variations, and the combined improvement of properties of disease resistance, yield and leaf quality are thougt to be the fundamental objective.