In vitro, Micropropagation of an Apple Malus × domestica Borkh. (Cultivar Anna) by Cloning of Apical and Axillary Shoot Buds

Abstract

Apple plant (Malus x domestica) is perennial fruit tree belonging to the family Rosaceae. Apple species have wide geographical distribution. Apple fruit has been considered to have high health benefits. Most of the species intercross. Since self-incompatibility is common, apples produced from seed are mostly interspecific hybrids, therefore it is difficult to produce true-to-type cultivars from seeds. The objective of our study, therefore, was to develop micropropagation protocol for Anna apple (Malus domestica Borkh), which is highly adapted for environmental conditions of Gaza Strip, using buds explants on MS medium. Buds were collected during the summer season produced higher percentage of buds establishment (75%) as compared to buds collected during other seasons. The best sterilization protocol was when we used 5% NaOCl, Tween 20, 70% Alcohol and 0.5% HgCl2. Apple buds (3.0 mm in length) were established by using AC, AA and CA as antioxidants. In culture establishment we used full strength MS media with several combinations of hormones BAP, GA3 and IBA. We obtained the best results in group B2 (1mg/l BAP, 0.5mg/l GA3 and 0.1mg/l IBA). The highest establishment rate was obtained for explant that produced 6.40 ± 1.14 shoots (1.76 ± 0.34 cm in length). In multiplication stage, we obtained the best results in group H1 (1mg/l BAP, 0.5mg/l GA3 and 0.1mg/l IBA). The highest multiplication rate was obtained for explant that produced 6.80 ± 3.03 shoots (1.88 ± 0.62 cm in length). In rooting stage we used two auxins IBA or IAA, the roots were formed only in two samples when we used 1 mg/l IBA and 0.1 mg/l IAA in half strength MS solid media. This research is considered the first in Gaza Strip for in vitro micropropagation of woody plant by using apple shoot buds.