Rhizogenesis of GF677, Early Crest, May Crest and Arm King stem cuttings during the year in relation to carbohydrate and natural hormone content

The rhizogenesis of GF677, Early Crest, May Crest and Arm King stem cuttings during the year was investigated. The results showed significant differences in the rooting percentage between different dates of cutting collection and also between the four cultivars. Among these, GF677 generally had the highest rooting percentage. Rooting of cuttings was high in October, November and February and relatively low in the periods March–September and December–January. Interactions among cultivars were also found.In this study, the possibly effect of endogenous factors (carbohydrate, hormone) was examined. In all cultivars, the starch level in peach shoot cuttings generally increases from January to November. Sucrose content in all cultivars was relatively high during the winter, but dropped during spring and summer and then increased again during the autumn. The level of sugars (soluble reducing sugars) during the year was relatively higher in May and September when the shoot growth rate was high (poor rooting) and rather lower in January–March, August and November–December.Idole-3-acetic acid (IAA) and abscisic acid (ABA) concentrations in shoot cuttings of GF677 were found to be very high in April and relatively low in the period November–February.