INTERSPECIFIC HYBRIDIZATION INVOLVING BANKSIA-PRIONOTES LIND AND B-MENZIESII R BR (PROTEACEAE)

Interspecific pollen tube growth within the Banksia genus was investig ated using controlled hand pollinations of B. prionotes and B. menzies ii and a putative natural interspecific hybrid between B. prionotes an d B. hookeriana, registered in 1991 as the cultivar Waite Orange, was studied using morphological and biochemical characters. Success of pol len tube growth in the pistil following interspecific pollination to B . prionotes and B. menziesii was largely related to taxonomic distance between the species, and the results indicated close affinity between the series Banksia and Crocinae. Control of pollen tube growth in the pistil was imposed in the pollen presenter, a specialized area of the distal style, and in the upper style. Hybrid status cv Waite Orange w as confirmed using morphological characters, and isozyme and arbitrari ly primed polymerase chain reaction (AP-PCR) analysis confirmed that t he two parent species were sister taxa.