Rooting Response of Rosa canina and Cotoneaster acuminatus to Different in vitro Factors

Abstract

The current study aimed to test the direct rooting response of rose and cotoneaster explants collected in winter and spring and grown on different culture media including WPM, B5 and MS supplemented with different concentrations of IBA and NAA. The experiments were arranged according to Complete Randomized Design (CRD) and were conducted at the plant tissue culture laboratories of the Faculty of Agriculture and Forestry, University of Duhok, Iraq during the period between December 2012 and August 2013. The results showed that explants collected in winter and spring failed to root in both genotypes tested except cotoneaster explants collected in spring. The best rooting performance was found on those grown on WPM medium containing 0.1 mgl-1 IBA by giving 5.62 roots per explant and the longest roots reached to 4.42 cm. This root formation required 22 days from culture date. Concerning shoot multiplication parameters recorded for both plants during this study, rose explants taken in winter and grown on WPM medium containing 0.1 mgl-1 IBA gave the maximum number of shoot per explant reached to 2.62. The maximum number of shoots per explant for cotoneaster (3.0 shoots/ explant) was recorded when the explants were collected in spring and grown on WPM medium supplemented with 0.5mgl-1 IBA. WPM medium gave the longest shoots (6.98 cm) on rose explants collected in spring and supplemented with 0.5mgl-1IBA. MS medium supplemented with 0.5mgl-1IBA gave the longest cotoneaster shoots estimated at 3.37 cm which also recorded the highest number of leaves (13.87 leaves). The highest of leaves per explant of rose reached 21.75 leaves/ explant which were obtained on explants grown on WPM medium supplemented with 0.1mgl-1 IBA. It can be concluded that cotoneaster plant can be rooted directly from explants collected in spring season, whereas rose plant need to undergo the developmental stages of usual micropropagation protocols