FIELD-EVALUATION OF TISSUE-CULTURED PAPAW CLONES IN QUEENSLAND

Field performance of tissue-cultured clones of papaws established eith er from adult tissue of a high-yielding female plant or from juvenile tissue of seedlings (2 females and 2 hermaphrodites) was compared with seedling controls. All tissue-cultured plants had strong root systems and established more quickly than seedlings. Plants from adult tissue (TCA) had a reduced juvenile phase, as evidenced by increased circumf erence, lower height of first flower, reduced time to harvest, and hig her fruit numbers per metre of stem. Planting date affected node numbe r of first flower for TCA plants but not seedlings. TCA plants had hig her yields than seedlings when planted in spring, and this could lead to improved commercial practice. Differences between clones establishe d from juvenile tissue and their respective seedling controls varied a nd were not consistent with a reduced juvenile phase. Four dwarf off-t ype plants (<1% of population) originated from a single bud explant.