Developmental Morphology of Platycerium coronarium (Koenig) Desv

Abstract

The growth habit and certain developmental aspects of Platycerium coronarium (stag's horn fern) are described. Starting from the primordial stage, the nest and pendulous leaves develop to maturity in 90 and 80 days respectively. The fertile lobe, which is part of the pendulous leaf, reaches its maximum size in 40 days. The morphogenesis of the nest leaf is more variable, and it matures and deteriorates earlier than the pendulous leaf. The acrostichoid sorus formation is completed in 3 weeks from inception and spore dispersal takes place when the fertile lobe is about 100 days old. The area of the fertile lobe and number of spores produced were determined. On Knop's agar medium the gametophytes develop in 2 months and 85 per cent of them are unisexual (both male and female) and 15 per cent bisexual. Less than 1 per cent of the gametophytes give rise to sporophytes. The juvenile leaves are simple, displaying open dichotomous venation; the first nest and pendulous leaves are produced 24 months after the date of spore germination.