Seasonal effects with grafting walnuts and rooting hazel cuttings : A thesis submitted in partial fulfilment of the requirements for the degree of Master of Horticultural Science in the University of Canterbury [Lincoln College]

Abstract

Techniques for improving walnut grafting were examined in a series of experiments. Scionwood was collected in June, July, August and September. Rootstocks were grafted in June, July, August and September using freshly-collected scionwood or cold-stored wood from the previous months. The best combination in terms of graft take and scion growth was found to be grafting in July or August with wood collected in July or June. This timing balanced the good callus growth of early collection times with the rapid scion bud growth of late winter. Graft take was improved by cutting stocks 10 days before grafting and storing at 27⁰C. The application of IAA, GA₃ , BAP or ABA to the scion and stock did not give significantly different scion growth, although BAP did appear to improve graft take. The rooting of hardwood cuttings of hazel was poor for all times of cutting collection, type of wood, and IBA concentration. The importance of using good quality propagating material was stressed.