In vitro micrografting of Ferragnes and Ferraduel almond varieties on clonal rootstocks of almondxpeach hybrid, GF-677 and Garnem (GN-15)

This study was carried out in Biotechnology laboratory of Faculty of Agriculture, Department of Horticulture at Dicle University during 2011-2012. In this study, shoot tips (0.5-1 cm) of Ferragnes and Ferraduel were micrografted on the clonal rootstocks of GF-677 and Garnem. Micrografted plants were transferred to MS medium containing three different combination of auxin-cytokinin (0.5 mgl-1 BAP + 0.1 mg l-1IBA and 0.5 mg l-1IBA + 0.1mgl-1BAP) with a control group (PGR free). Two types of rootstocks were used as rooted and rootless. Successful micrograft rate (%), shoot length (mm), rooted micrograft (%), displayed micrograft rate (%) and callus induction rate (%) were examined.In GF-677 rootstocks, micrografting rate was 100% for Ferragnes and 80% for Ferraduel. Micrografting rate was 100% in both Ferragnes and Ferraduel on the rooted GF-677. In Garnem rootstocks, micrografting rate was 100% for Ferragnes, 93% for Ferraduel but in the rooted Garnem, micrografting rate was 100% for both of cultivars. Shoot development was observed only in the micragrafted plants of the rooted GF-677. Shoot development was observed in both of the varieties in BAP containing medium, and values were reported as 8.66 mm and 10.40 mm for Ferraduel and for Ferragnes, respectively. Shoot growth was observed in both rootless and rooted Garnem rootstocks. Shoot growth of rootless rootstocks in IBA containing medium was ranged from 22.91 mm in Ferragnes to 26.16 mm in Ferraduel, while shoot growth of rooted rootstocks in BAP containing medium was ranged from 24.80 mm in Ferraduel to 28.06 mm in Ferragnes. The highest rate (20%) of displaced micrografts was reported on the rootstocks of Garnem when Ferraduel was micrografted on Garnem in terms of displaced micrografts. No displaced micrografts was reported when the rooted rootstocks were used. In terms of rooting percentages, a 30% to 40% of rootless explants were rooted when the rootstocks were transferred to a growth medium. This is the first report on micrografting of standard almond cultivars on the commercial rootstocks, GF-677 and Garnem. As a result of this study, some basic information was reported on the effect of auxin-cytokinin combination, the effect of rootstock types; with or without root on the development of micrografting protocol. We hope that this study will be a model for the future micrografting studies on the different plant species, especially on fruit species for the different purposes. Keywords: Almond, GF-677, Garnem, Clonal Rootstock, Micrografting, Micropropagation