If they are incompatible, they survive normally and grow side by side as two homokaryons. Then they produce conidia again.
Because the OC type encounters more compatible conspecifics than the other types, many heterokaryons will be formed but only a few (low-fitness) homokaryons with only h nuclei.
They assumed that the parasitic allele was competitively superior in heterokaryons but lowered the fitness of homokaryons. They concluded that vegetative incompatibility could evolve as a consequence of the existence of such a parasitic gene, but whereas their model considers only two vegetative compatibility groups (VCGs), in reality (many) more VCGs are found in ascomycete species.
In formulas (B2a) to (B2d), the first part of the equation to the right of the equals sign is the fraction of that genotype produced by homokaryons. The second part is the fraction produced by the heterokaryons.
Fritsche crossed homokaryons together to make the U1 and U3 hybrids, she did so without the knowledge that they had the potential to mate.
Thousands of these homokaryons from commercial and wild sources are used in our breeding program,
Our lab has had the best luck obtaining homokaryons through spore germination.
MAS allows us to use a DNA-based marker system, to determine which of the homokaryons will provide us with the traits we desire, without having to wait for new crosses to be cropped.
This marker was integral in the development of our patented brown hybrids; where one of the steps was to cross homokaryons from a white commercial strain with homokaryons from an old-fashioned brown strain.
It was not until we crossed homokaryons from U1 with homokaryons from the Old-Fashioned Brown and created an intermediate hybrid, that we finally started to have success.