以面包酵母BY-14为出发菌株制备单倍体,通过单倍体的分离和配型的鉴定(α/a),获得5株a型,7株α型。比较12株单倍体菌株的发酵性能,筛选出发酵性能及生物量与亲本基本相当、麦芽糖发酵力高及葡萄糖阻遏作用弱的17α和70a单倍体菌株。以亲本BY-14为对照,对这2株单倍体进行不加糖面团发酵力及耗糖曲线的测定,实验结果显示,2株单倍体在葡萄糖基本消耗殆尽后,迟滞期均较短,可以较快地转入麦芽糖的代谢,为后续分子育种提高麦芽糖的利用速度奠定良好基础。

Spore-producing and haploid matching(a/α) experiments were carried out to obtain 5 haploids with mating type a,and 7 haploids with mating type a from the parental diploid BY-14.The fermentation capability of the haploid strains were studied,and two haploids(17αand 70a) with high maltose fermentation ability and low glucose effect degree were identified to investigate the fermentation kinetics in maltose-free,glucose-free and mixed LSMLD medium respectively.Both the haploids had short lagging phases of maltose metabolism after glucose exhaustion, which provide a good base for breeding more excellent yeast strain with higher speed of maltose metabolism.