Development of high yielding and early flowering new coconut cultivars with exotic Pollen

Abstract

Coconut is a socio economically vital crop in Sri Lanka. Due to its recently discovered health benefits, coconut industry is flourishing across the globe. As coconut hybrids (or crosses between varieties) produce 40% more yield than conventionally grown Sri Lankan Tall variety, introduction of new hybrids is the way forward for supplying nuts for increasing demand. Over the past 80 years, Sri Lankan coconut breeders have utilized all the locally available genetically diverse Dwarfs (Green, Yellow and Brown) and exotic accessions available locally such as San Ramon in breeding programme. As a result, by the start of new millennium, coconut breeding was almost at a dead end due to lack of genetically diverse material. Based on the results of previous molecular studies, 23 exotic coconut accessions were imported from 2002 to 2004 predominantly with South East Asian and Pacific origins via embryo culture. Seedlings were then generated and planted at the field gene bank to broaden the genetic base. In the current study, to speed up the coconut breeding programme, pollen from selected exotic germplasm viz. Rennel Island Tall (RIT), Tagnanan Tall (TAGT), Malayan Red Dwarf (MRD) were imported and successfully crossed with Sri Lankan Tall and Sri Lankan Green Dwarf to develop six new coconut crosses. In addition, the pollen from a previously acquired exotic accession Brazilian Green Dwarf (BGD) was also used in this crossing programme. According to the results of the multi-locational analysis for mean flowering time, early nut yields and kernel productivity, two promising new crosses viz. T x MRD, T x RIT were identified. These crosses have a great potential to be released in near future as commercial cultivars for the National Coconut Replanting Programme in Sri Lanka