The Young Gametophyte of Lycopodiella lateralis and the Role of the Intermediate Shaft in Development of Lycopodiella Gametophytes

Abstract

Abstract Spores of Lycopodiella lateralis germinate rapidly in illuminated cultures as is typical for most Lycopodiella spores. The young gametophyte develops into a solid, green, spherical primary tubercle. Mature gametophyte development occurs at the top of the primary tubercle by the formation of a crown with photosynthetic lobes. An intermediate shaft reported for other Lycopodiella gametophytes fails to form. Comparisons were made between intermediate shafts of Lycopodiella gametophytes growing in nature and in culture. In well illuminated conditions the intermediate shaft does not form as it does on poorly illuminated gametophytes. If the gametophyte development starts partially covered by soil, long intermediate shafts can be produced. The intermediate shaft raises the top of the young gametophyte to the top of the soil where a sexually-mature gametophyte develops and sexual reproduction can take place. The intermediate shaft provides the possibility for a young gametophyte in unsuitable illuminati...