What kind of soil is needed to grow C-Fern sporophytes? Does soil pH need to be adjusted?

C-Fern sporophytes grow well in commercially available ProMix® potting mix. ProMix works very well for both greenhouse or terrarium culture (see mini-terrarium instructions) and has some starter fertilizer in it to get things going. Soil pH is not adjusted when using Promix potting material. Sporophytes grown in mini-terraria typically need no additional fertilization to grow […]

How can I grow sporophytes to maturity?

The easiest way for most users to cultures sporophytes is to use a Mini-terrarium constructed from a plastic drink bottle. Instructions for construction and use of the Mini-terrarium are available at Sporophyte Culture – Mini-terrarium. Bottles as small as 8-ounces or as large as 2-liters can be used. The commercially available potting soil (i.e. ProMix®) […]

Why do you sometimes get genetic ratios that are quite different from the expected?

“Unexpected” genetic ratios are typically associated with sampling error and an unconscious tendency to bias counts towards one of the phenotypes. Students should be carefully instructed in the proper ways of data collection, including a very thorough explanation of appropriate random sampling. One common problem is the tendency to ‘select’ individuals for counting rather than […]

Will contaminants such as fungi and algae affect my C-Fern cultures?

C-Fern cultures are largely resistant to many fungal contaminants, although some fungi can be pathogenic. For routine observations, the presence of some contamination will not generally interfere with gametophyte growth or development. Contamination by certain types of algae can be much more destructive since contamination can spread rapidly and infect other cultures. If algal contamination […]

I have problems seeing swimming sperm under the dissecting scopes.

Magnification is typically not the problem since sperm can be adequately visualized even at a total magnification of only 25 X. Usually, difficulties observing sperm are often associated with improper or insufficient illumination. Bottom (transmitted) illumination is preferred. If adjustments are possible, try increasing or decreasing the intensity of the light source. Also, if a […]


A brief overview of a model plant system C-Fern® is a specially derived cultivar of the tropical homosporous fern, Ceratopteris richardii, commonly referred to as “water fern”, which is also used as an aquarium plant.