Effects of growth medium, a hormone, and stem-cutting maturity and length on sprouting in Moringa oleifera Lam.

摘要

Seed propagation in Moringa oleifera Lam., a multipurpose tree, is becoming increasingly difficult as the seeds are over-utilised for diverse products including oil for machine lubrication and cosmetics. Current vegetative propagation methods use 45 cm-1.5 m long hardwood or softwood cuttings, which further threaten proliferation, while information on the hormone and growth medium requirements for propagation is not available. The effects of growth medium (e.g., a light sandy soil vs. AgSSIP, a 1:1 (w/w) mix of coconut coir and teak sawdust), a hormone (i.e., a naphthaleneacetic acid [NAA]-talc formula), stem-cutting maturity (i.e., hardwood, semi-hardwood, or softwood), and cutting size (15, 30, 45, or 60 cm-long) on growth performance were investigated. A split-plot design in two blocks, with 48-treatment combinations, was used to collect data on shoot production and survival, shoot length, and leaf production in M. oleifera for over 10 weeks. Hardwood cuttings sprouted best with the highest number of shoots. The application of NAA-talc had a significant effect on sprouting and induced shorter shoots with greater numbers of leaves than the no-hormone treatment, while mortality was highest in NAA-treated stem-cuttings in AgSSIP-mix. Hardwood and semi-hardwood cuttings, 30 cm in length and planted in a light-sandy soil performed best and produced the longest shoots. The shortest shoots were produced on 15 cm-long softwood cuttings. Thus, vegetative propagation of M. oleifera can best be achieved using hardwood or semi-hardwood cuttings at least 30 cm-long, planted in a light sandy soil with an NAA-talc treatment, or in AgSSIP-mix without NAA-talc treatment.