Plurispore development of Cladosiphon okamuranus Tokida (Chordariaceae, Phaeophyta).

Abstract

Development of plurispores and effects of temperature on their attachment to substrata were studied using mature plurilocular sporangia of Cladosiphon okamuranus Tokida. Development of plurispore showed the disc type, a large number of assimilatory filaments were found to develop from the middle or central part of a disc. These compact and parallel assimilatory filaments formed pseudoparenchyma (multiaxial) with abundant lateral branches. The attachment and development of a plurispore were affected significantly by temperature. Suitable seeding temperature was found to be 17-26º and 26 being optimum for successful attachment. At a temperature over 26ºC, the plurispore could not attach tightly to a substratum or developed poorly.