IN VITRO PROPAGATION OF Paulownia hybrid (P. elongata x P. fortunei) TREE

Abstract

This study was carried out in Plant Tissue Culture Laboratory, Horticulture Department, Faculty of Agriculture, Zagazig University, Egypt throughout the period of 2016 to 2018. An efficient protocol was achieved for in vitro mass propagation of Paulownia hybrid (P. elongata x P. fortunei) by using seeds. The seeds were germinated onto different liquid Murashige and Skoog (MS) medium strength (¼, ½, ¾ and full) free from growth regulators. The highest germination percentage (53.33%) was obtained with full MS. Different concentrations (0.0, 0.5, 1.0, 2.0, 4.0 or 8.0 mg/l) of benzyladenine (BA) or isopentenyladenine (2iP) were tested during multiplication stage. The best treatment for shoot multiplication (31 shoots/explant) was 8.0 mg/l BA. Multiplied shoots were transferred to MS medium containing different concentrations (0.0, 1.0, 2.0, 3.0 and 4.0 mg/l) of indole-3- acetic acid (IAA) or naphthalene acetic acid (NAA). NAA was more effective than IAA for in vitro rooting of Paulownia. All tested concentrations of NAA gave (100%) rooting percentage. MS medium supplemented with 2.0 mg/l NAA produced the best root and shoot growth. Rooted Plantlets were successfully acclimatized in peat moss or peat moss and sand (1:1 and 1:2, V/V) media. On the other hand, prefer using peat moss and sand (1:2, V/V) because its was economic method.