Early grafting of chestnut by green grafting
Traditional fruit cultivars are ontogenically very old, and therefore difficult to root. That is why traditional grafting methods are normally the way to produce new chestnut trees for fruit cultivars. Nurseries usually graft onto bare root or potted Phytophthora resistant hybrid rootstocks, produced by vegetative means (stooling, rooted cuttings or micropropagation). Producing a grafted plant takes two or three years, with an average grafting success rate of 65%; therefore, after three years there is a percentage of loss where plants cannot be reused due to deformations produced by the grafting process. To improve this yield, 8 Galician cultivars were grafted onto green vitroplants (green grafting). Cultivar herbaceous scions were collected during the summer with 3-5 mm diameters and grafted onto just acclimated vitroplants under foggy atmosphere. Grafting success was more than 75%, and the scion resumed growth within 15 days. Failed grafts were pruned and rootstocks were recycled for traditional grafting with no apparent deformities. Thus, green grafting reduces time to produce grafted plants within one year, successes were higher and the process allowed the recycling of rootstocks when grafting failed.
Cuenca, B., Lario, F.J., Luquero, L., Ocaña, L. and Mandujano, M. (2018). Early grafting of chestnut by green grafting. Acta Hortic. 1220, 141-148
Castanea, in vitro, micropropagation, Phytophthora, rootstocks, fruit cultivars