Characteristics of Hardwood Cuttings Influence Rooting of Actinidia arguta (Siebold & Zucc.) Planch.

Abstract

Root development of hardwood cuttings of Actinidia arguta was investigated in relation to the size of cuttings and the number of buds. Dormant shoots of 13 Actinidia arguta cultivars and lines were cut into lengths varying from 3.5 to 18 cm and containing one to nine buds. After being treated with 0.3% indolebutyric acid in talc, cuttings were stuck into oasis foam cubes and placed under intermittent mist. Actinidia arguta lines and cultivars included 74-46, 74-55, 124-40, 125-40, 127-40, 119-40-B, `Meader Male', `Meader Female #1', `Geneva #1', `Ananasnaja', `Michigan State', A. arguta cordifolia (Miq.) Bean 1563-51, and a New Zealand A. arguta cordifolia selection. Cultivar significantly affected number of roots, root grade, and length of longest root. In general, cultivars with the highest rooting percentages also had the most and longest roots and the highest root grades. The best cuttings for root formation had eight to nine buds (with three to four in active growth), diameters <2 mm, and lengths >10 cm. Cuttings with five to seven buds (with one to three in active growth), diameters between 2 to 8 mm, and lengths >8 cm exhibited the best root development in terms of number of roots formed, root length, and root grade.