Nine-tenth of all photosynthesis of world (85 - 90%) is carried out by

Nine-tenth of all photosynthesis in the world (85 - 90%) is carried out by algae of the ocean.
Algae are a diverse group of predominantly aquatic photosynthetic organisms, including cyanobacteria, green algae, and other eukaryotic algae. They account for 85 - 95% of the photosynthesis that takes place on Earth.
Algae have a wide range of antenna pigments to harvest light energy for photosynthesis giving different types of algae their characteristic colour.
Algae are indispensable because they produce about half the oxygen in Earth's atmosphere.