TABLE 1

Phenotypic characteristics of su1 and su2 mutant alleles

Suppression levelaLongevity (cm)bmtDNA rearrangementscMycelium morphologydFertilityeGermi-nationf
WT9.5 ± 1.0α, β, γGreen mycelium, with dense aerial hyphae+++Good, WT
su1-1+8.1 ± 0.9WTWT+++Good, WT
su1-5+10.3 ± 0.9NDWT+++Good, WT
su1-13+9.6 ± 0.8NDMycelium darker than WT+++Good, WT
su1-19+8.9 ± 0.7NDWT+++Good, WT
su1-25++7.1 ± 0.9WTDark or white mycelium without aerial hyphaePoor, VM
su1-26++7.8 ± 1.1WTMycelium with white and green sectorsPoor, VM
su1-31++6.7 ± 0.9WTWhite mycelium without aerial hyphaeGood, WT
su1-37++7.4 ± 0.8WTMycelium darker than WT++Good, AM
su1-39++8.0 ± 0.6WTMycelium darker than WT++Good, AM
su1-40+9.5 ± 0.7NDWT+++Good, WT
su1-42+8.1 ± 0.6NDWT+++Good, VM
su1-47+10.1 ± 0.9NDWT+++Good, WT
su1-48+9.7 ± 1.0NDWT+++Good, WT
su1-49+10.3 ± 1.3NDWT+++Good, WT
su1-50+19.8 ± 5.4NDMycelium with a rhythmic growthGood, VM
su1-51+>150WTVery dark and slow growing myceliumGood, VM
su2-1+8.8 ± 0.6WTWT+++Good, WT
su2-3+8.4 ± 0.7NDWT+++Good, WT
su2-5++?WTWhite myceliumPoor, VM
su2-6++6.6 ± 0.6WTDark green mycelium without aerial hyphaeGood, VM
su2-10+10.9 ± 0.9NDWT+++Good, WT
su2-11+9.0 ± 1.1NDWT+++Good, WT
su2-12+10.0 ± 0.5NDWT+++Good, WT
su2-14++8.9 ± 1.3WTMycelium growth slightly slower than WT+++Good, AM
AS2-111.7 ± 0.9WTWT+++Good, WT
AS2-211.7 ± 1.5WTWT+++Good, WT
  • a The suppression level brought by the mutation as a measure of the restoration of pigmentation of 193 su ascospores; +, 193 su ascospores are light green; + +, 193 su ascospores are dark green; —, ascospores are white.

  • b The longevity in centimeters (±SD) of the indicated strains measured on M2 minimum medium. ? indicates that su2-5 does not present senescence with a complete stoppage but a stop-and-start growth alteration. This occurs after about 7/8 cm of growth. At that point, mtDNA is modified in the su2-5 stain as seen in wild type.

  • c The mtDNA rearrangements present during the terminal phase of senescence (WT means that no difference is observed when compared to wild type; ND, not determined). The mtDNA rearrangements consist in the amplification of circular double-stranded molecules of small regions of the mtDNA (senDNA, Cummings et al., 1979). In wild-type strains, three different regions (called α, β and γ) are found amplified (Dujon and Belcour, 1989).

  • d The morphology of the mycelium when cultivated on M2 medium (WT means that no difference was observed when compared to wild type).

  • e A visual estimation of the amount of perithecia (fertility) observed after fertilization with wild-type conidia.

  • f The efficiency with which homokaryotic spores containing the indicated allele germinate. Good indicates that mutant spores have a good germination percentage, poor that they have not. WT, AM (altered morphology), and VM (very altered morphology) refer to thallus appearance after germination of mutant ascospores. No differences were observed whether the mutant alleles were associated with one mating type or the other.