Most activities use the wild type C-Fern (RNWT1) spores also known as the C-Fern Standard Genotype. Other strains derived from the wild type are useful for investigations in development, genetics, physiology, and ecology. Below is a listing of possible available strains and a brief description.

Genotype Code Description
wild type RNWT1 Basic C-Fern genotype
Single Gene Nuclear Mutants
abscisic acid tolerant abr48 Gametophytes tolerant to the plant growth regulator, abscisic acid
dark germinator dkg Does not require light to initiate spore germination
day-night responder dnr1 Gametophytes and sporophytes grow very slowly and accumulate massive amounts of starch in their plastids under constant light. A day/night cycle, or reduced light, accelerates growth and causes depletion of excess starch reserves
FUDR tolerant fdr1 Gametophytes tolerant to the nucleotide analog 2'-deoxy-5-fluorouridine
highly male him1 Developmental gametophyte mutant showing a ‘supermale’ morphology. Forms high numbers of males (even in isolate cultures) with increased numbers of antheridia on both males and hermaphrodites
maleless her1 Does not form male gametophytes. Insensitive to the male-inducing pheromone
mutant hunt MIX An excellent way to introduce students to the wide variety of visible mutants that can be induced with the mutagen, EMS. This mixture contains wild type and mutant stocks, such as albino, pale, polka dot, lethals and a variety of other types. Mutant frequency greater than 10%. Spores do not contain EMS
non-etiolated det30 Gametophytes do not show elongation response when grown in the dark
polka dot cp Chloroplasts form clumps that resemble polka dots in both gametophyte and sporophyte tissue. Recessive in sporophytes
salt tolerant stl2 Gametophytes and sporophytes tolerant to Na+ and Mg2+ salts
sleepy sperm zzz1 Sperm are released normally, but swimming is delayed. After a few minutes some sperm ‘wake up’ and swim slowly to moderately while the rest show only slight movement and remain close to the gametophyte. Excellent for observation at high magnifications (greater than 50X). Self-fertile
slow-mo sperm slo1 Sperm are released normally and swim immediately. All but a few show very slow movement. Excellent for observations at high magnifications (greater than 50X). Self-fertile.
F1 Stocks Single gene mutants X wild type (RNWT1)
F1 pale pal1/PAL1 Spores from an F1 sporophyte produce gametophytes in a 1:1 ratio of pale mutant to green wild type. Pale gametophyte mutants grow nearly as well as wild type and are easily distinguished. The recessive mutation results in a 3:1 ratio in the F2 sporophyte generation.
F1 polka dot cp/CP F1 gametophytes segregate in a ratio of 1 wild type to 1 polka dot. F2 sporophytes segregate in a ratio of 3 wild type to 1 polka dot.
Double nuclear gene mutants
herbicide tolerant (glyphosate tolerant and paraquat tolerant) glt1 pq45 Gametophytes and sporophytes tolerant to glyphosate-containing herbicides, e.g. RoundUp*, (incompletely dominant in sporophytes) and to paraquat (recessive in sporophytes).
non-etiolated det30 Gametophytes do not show elongation response when grown in the dark. The non-etiolated genotype is currently available only as a double mutant with her1. This enhances visualization of the non-etiolated det30 phenotype in dark-grown cultures.