In Vitro Propagation of some Pear Rootstocks

Abstract

The rootstock is very important to the growth and development of the tree as a necessary part of a grafted fruit tree. In this study, seeds of several pear species were collected for tissue culture, its germination, subculture and micro-propagation were investigated. The chilling requirement of different wild pear species also were compared to select the rootstock strains which need low chilling requirement and more suitable under Egypt condition. Three different media were tested for multiplication M1: BA at 2mg/l + Kin at 1mg/l + NAA at 1mg/l, M2: 2ip at 1mg/l + Kin at 0.5 mg/l + IBA at 0.5 mg/l, M3: BAP at 4 mg/l + TDZ at 1mg/l + IBA at 1mg/l.in ten pear rootstocks. It was different response among different rootstock genotypes in number of shoots and shoot length. The media M1 and M3 were recorded the higher value of shoot number, while M2 were recorded the highest value of shoots length. For rooting stage different concentration of IBA (1, 2 and 3 mg/l) and IAA (0.5, 1 and 2 mg/l) were tested and the result showed that, low concentration of IBA or IAA were more suitable for rooting percentage and root number, and the effect of IBA on rooting were better than IAA. Pyrus. betulifolia and P. calleryana had the highest rooting percentage and the IBA 1 mg/l was the best medium. In vitro propagation of some wild pear rootstocks can be achieved, different growth regulators of auxin and cytokinin had effect on pear proliferation stage. In the rooting stage, the low concentration of IBA were better than high concentration and IAA. P. betulifolia, P. calleryana and P. serrulata were high in survival percentage and were more suitable for in vitro propagation of pear rootstocks in Egypt, moreover they had low chilling requirement.