TABLE 3.

Appearance of zygotes in intra- and interspecies crosses

Crossa	Mating type	Frequency of zygotesb	Presence of homo- or heterokaryonsc
A
Y184 × Y185	MATα × MATa	0.40	n.p.
Y169 × Y170	MATa × MATα	0.30	n.p.
Y184 × Y169	MATα × MATa	0.22	n.p.
Y244 × Y245	MATα × MATa	0.30	n.p.
B (Y339 × Y345)	MATα × MATa	0.05	n.p.
C
Y184 × Y245	MATα × MATa	0.26	n.p.
Y185 × Y244	MATa × MATα	0.33	n.p.
Y169 × Y244	MATa × MATα	0.33	n.p.
Y170 × Y245	MATα × MATa	0.30	n.p.
D
Y184 × Y345	MATα × MATa	0.08	Homokaryons
Y184 × Y257	MATα × MATa	0.10	Homokaryons
Y184 × Y344	MATα × MATa	0.05	Homokaryons
Y185 × Y339	MATa × MATα	0.09	n.p.
Y185 × Y257	MATa × MATa	0.19	n.p.
Y185 × Y344	MATa × MATa	0.15	n.p.
E
Y345 × Y257	MATa × MATa	0.03	Homokaryons
Y345 × Y344	MATa × MATa	0.15	Homokaryons
Y257 × Y344	MATa × MATa	0.07	Homokaryons

^aA, intraspecific crosses within the sensu stricto group; B, intraspecific crosses within the sensu lato group; C, interspecific crosses between yeasts belonging to the sensu stricto group; D, interspecific crosses between yeasts belonging to the sensu stricto and sensu lato groups; E, interspecific crosses between yeasts belonging to the sensu lato group. 

^bNote that the frequency of zygotes is estimated on approximately 1,000 cells. 

^cn.p., not performed.