ddRADseq reveals the relationships of harakeke and wharariki (Phormium species, Asphodelaceae) and selected weaving cultivars in Aotearoa New Zealand

Abstract

Abstract Phormium tenax (harakeke) and P. cookianum (wharariki) are important plants for Māori, particularly as weaving materials. At least 60 different cultivars were selected for specific purposes; most are harakeke, but some are suspected hybrids between the two species. We used next-generation sequencing to examine the relationships of wild and cultivated Phormium. We found that the two species could be distinguished genetically, despite evidence of hybridization and introgression. We observed genetic structuring within harakeke and most of the cultivars clustered with wild North Island samples. Our results indicate that it is possible that the populations of harakeke on offshore islands (Norfolk Island, the Kermadec Archipelago, Rēkohu and the subantarctic islands) are all introduced, either by Māori or early European settlers.