The effects of IAA on the growth, chlorophyll and protein content of Ulva pertusa Studies on chemical constituents of green algae Ulva pertusa Effects of salinity, light and nutrients on photosynthesis of sterile Ulva pertusa Comparative Studies on the Allelopathic Effects of Ulva pertusa Kjellml, Corallina pilulifera Postl et Ruprl, and Sargassum thunbergii Mertl O. Kuntze on Skeletonema costatum (Grev.) Cleve