Rooting and Growth of Cuttings from Ethylene-Low or Ethylene-High Sensitive Miniature Rose Genotypes under Mist Condition

摘要

Using cuttings is a main approach in the clonal propagation of herbaceous or woody ornamental greenhouse crops. Rose plants are commercially propagated by hardwood and softwood cuttings. Ethylene is a gaseous plant hormone that plays important role in adventitious root initiation of plant species and it has been suggested that an ethylene-mediated signal transduction pathway is implied in root initiation. This study was conducted to evaluate the rooting ability and bud growth in miniature rose genotypes showing high-sensitivity or low-sensitivity to exogenous ethylene treatment, under mist environmental conditions. Data showed that 98.3% of cuttings were rooted whether treated or untreated with indole-3-butyric acid (IBA) and rooting ability did not depend on ethylene sensitivity of investigated genotypes. Although axillary bud growth was delayed in one of the low sensitive genotypes, time to axillary bud growth was not significantly affected by cutting size and IBA treatment. In that ethylene low-sensitive genotype, less than 20% of cuttings showed bud growth after 16 days, while it was about 90% in other genotypes. Plant height, dry weight of roots and shoots showed significant differences among genotypes, regardless cutting size or IBA treatment. The mean rooting time was shorter than 12.3 days for all genotypes, except for one genotype which required 20 days for rooting. Results revealed that all genotypes showed optimum shoot growth and the highest rate of rooting under mist and fog conditions, regardless of their ethylene sensitivity or IBA application.