Effect of tree age, scion source and grafting period on the grafting success of cashew nut (Anacardium occidentale L.)

Abstract

Cashew (Anacardium occidentale L.) can be propagated by seed or vegetative propagation. Grafting is the best method for large-scale asexual propagation of cashew. An assessment of grafting success of cashew nut was conducted at Chikwawa Estate nursery where graft-take was compared for scions obtained from different populations of different ages and then grafted from the month of August to October 2008. Mature and immature scions were collected from forty cashew accessions of age 12 and 20 years in Liwonde, Nkope, Kaputu and Chikwawa populations. Results show that scion source and tree age had no effect on grafting success. However, there were significant differences (p ≤ 0.05) for scion type. Immature scions performed better in August while mature scions did well in October. The differences are attributed to differences in temperature in the two months that further affect rate of healing of graft unions. There were significant differences (p ≤ 0.05) for graft take of mature scions as compared to immature scions with 57.5 and 72.5% in August and October respectively. There were no correlations between cashew tree age and scion type on the grafting success suggesting that cashew scions could be collected from trees of different ages to be used for grafting. Key words: Anacardium, grafting, graft-take, season, scion type.