Prophylactic Treatments of Cycas Stem Wounds Influence Vegetative Propagation

Abstract

Cycad stem cuttings will develop adventitious roots if the open wound is first treated with a sealant to protect the exposed parenchyma tissue. The commercial pruning wound sealant that is often employed for this purpose is not available in many locations. We used commonly available products as a prophylactic sealant on Cycas edentata , Cycas micronesica , and Cycas nitida cuttings to determine efficacy for sealing the wound and enabling adventitious root formation. Success was quantified after 7 months in a sand propagation substrate. Mortality was 100% for control cuttings with no wound sealant and about 60% for cuttings with candle wax as the sealant. Cuttings that received petroleum jelly, lanolin paste, modeling clay, honeycomb wax, or commercial pruning sealant exhibited 100% survival. Success in adventitious root formation ranged from 75% to 92% among the five successful prophylactic treatments and did not differ among the species. The results indicated that four of the products we evaluated were as effective as commercial pruning sealant for treating the exposed parenchyma on Cycas stem cuttings and enabling asexual propagation success. The candle wax was less effective because it was brittle and cracked to expose the stem’s parenchyma tissue.