In Vitro Cultures of a Fern Callus

Abstract

IN recent years, several reports of the successful growth in sterile culture of callus tissues derived from various pteridophytes have appeared¹. A callus culture possessing several unusual morphological, cytological and metabolic features has been obtained from gametophytes of Pteridium aquilinum (L.) Kuhn, var. latiusculum (Desv.) Underw.², which had been growing in sterile culture on an agar medium containing Knudson's solution of inorganic salts³, Berthelot's trace element solution⁴, 2 per cent glucose and 0.5 gm./l. yeast extract (autoclaved) at Harvard University, United States. Soon after these gametophyte cultures were brought to Manchester, England (in September 1950), a callus-like growth was observed in one of the tubes. When subcultured on to the same medium, with Knop's inorganic salt solution⁴ substituted for Knudson's, the abnormal tissue continued to grow in a disorganized manner. It has now been through sixteen passages, each of four to six weeks duration, and in each passage there has been a six- to ten-fold increase in the size of the inoculum.