Complex sentence: The Central Plantation Crops Research Institute (CPCRI) which is the Regional Station conducts research in arecanuts which is basic commercial crop and breeding, production and protection and drought resistance in cocoa.
Split into simpler sentences: The Central Plantation Crops Research Institute (CPCRI) which is the Regional Station conducts research in arecanuts which is the basic commercial crop. It also heads research in the breeding, production and protection and drought resistance in cocoa.