Experimental crosses in Phormium confirm the lack of intrinsic barriers to interspecific hybridisation and the fertility of putative wild hybrids

Abstract This study examined the potential for hybridisation between species of Phormium by examining fruit and seed set following self, intraspecific, and interspecific hand pollinations among several genotypes, including representatives of P. tenax, P. cookianum subsp. cookianum, and P. cookianum subsp. hookeri. Plants from a putatively introgressed population of P. tenax and a number of plants of uncertain taxonomic affinity were also included. There was considerable variation in performance as paternal and maternal parent, both among genotypes and taxa. Results confirm that all taxa are able to cross and produce fruit with filled seed, and we found no convincing evidence for the presence of intrinsic crossing barriers among taxa.