IN VITRO PROPAGATION FOR PEACH ROOTSTOCK (NEMAGUARD)

A procedure for micropropagation ofNemaguard peach rootstock was developed using stem nodal segments as explants for in vitroestablishment. Hundred percent of explants survived with high proliferation of shoots, growth percentage to survival and average shoot length was obtained on Murashige and Skoog (MS) basal medium supplemented with a combination of 0.5 mg/L 6-benzyl amino purine (BAP) plus 0.2 mg/L indole acetic acid (IAA). The maximum number of proliferated shoots (7.0 shoots/explant) was obtained on MS medium supplemented with 3.0 mg/L BAP + 0.5 mg/L 2-isopentenyladene (2iP). Meanwhile, MS basal medium without growth regulators induced the highest shoot length compared with other treatments. However, shoot elongation decreased with the increase of BAP concentration. Ninety percent of the shoots rooted on MS medium supplemented with 3.0 mg/L indole butyric acid (IBA) to obtain complete plants with the maximum average root number/shoot (5.8). On the other hand, the maximum root length (8.5 and 7.2 cm) was obtained when IBA or naphthalene acetic acid (NAA) were supplemented to half strength MS media at 3.0 mg/L. High survival, over 90%, was obtained when the plantlets were transferred to greenhouse conditions. The Nemaguard peach rootstock cans successfully micropropagated beginning with stem nodal segment without significant damage to mother plant. The in vitroNemoguard peach rootstocks were planted in Saint Catherine, South Sinai, Egypt where chilling requirements for producing the rootstock seeds are available for commercial production. Hence, it is encouraged to grow Nemaguard peach rootstock under S. Catherine conditions for commercial seed production.