C-Fern sperm can swim for over two hours at 25 °C in the Sperm Release Buffer (SRB) as described in the C-Fern Chemotaxis exercise – Chemical Attraction. (See also the C-Fern Manual for the formulation of SRB.) Sperm will swim a much shorter time in plain distilled water, although it is more than sufficient to […]
C-Fern is derived from tropical / subtropical species and requires warm temperatures, 28 °C (82° F) for optimal and consistent growth and development. The C-Fern Growth Pod and a simple light are all that are needed to achieve this. For large number of cultures, you can use the C-Fern Culture Dome with a light bank.
Temperatures below the optimum of 28 °C (82 °F), but above 20 ° C (68 °F), will not kill C-Fern cultures. However, spore germination and both gametophyte and sporophyte growth will be delayed. The cooler it is, the slower development will be.
C-Fern spores are quite large for fern spores, about 120 µm (microns). Surprisingly, human eggs, i.e. secondary oocytes, and C-Fern spores are similar in size and shape. A vial containing 300,000 C-Fern spores (ca. 240 mg) is a graphic demonstration of the number of eggs (primary oocytes) in the ovaries of a 7-year-old girl. Only […]
Standard C-Fern sowing density is 300 spores/dish (60×15 mm Petri dish). This standard sowing density gives more consistent results with respect to the ratio (or proportion) of male to hermaphroditic gametophytes). At lower densities, proportions of these types can be highly variable. Density can be reduced by adding more water before sowing or by using […]
C-Fern sperm can be seen at magnifications as low as 20X. The critical factor is light from below and proper adjustment of the light source. If all else fails, try placing a piece of aluminum foil with a pencil lead-sized hole in it under the Petri dish culture or slide. View sperm swimming in the […]
C-Fern Growth Pods are the easiest way to maintain cultures.
C-Fern antheridiogen, the pheromone which determines the sexual phenotype of gametophytes, can be easily harvested and used in experiments. Use old cultures of gametophytes, preferably those which are not contaminated, and carefully scrape the gametophytes from the surface. Next, freeze and then thaw the agar. The antheridiogen containing liquid will separate from the agar and […]
C-Fern spores can be evenly spread in Petri dishes by using nickel-chromium wire (ca 0.64 mm) in an inoculation loop holder. Nickel-chromium wires can be repeatedly flamed to achieve surface-sterilization. This thinner wire gives superior results compared to using thicker plastic or metal spreaders. However, if you take care, thicker spreaders will work – even […]