We have recently found that when mutants in the CMJ030 (mt-) background are crossed to standard lab strain 21 gr (mt+), the “Sager strain”, high efficiency mating and zygote germination is obtained. Because 21 gr has a cell wall (CW15+) and it is wild-type for nitrate reductase (NIT+), it should be possible in a single cross to generate walled, NIT+ versions of mutants of interest. For more information, see CC-1690 wild type mt+ [Sager 21 gr].