A high genetic diversity revealed between commercial rose cultivars by RAPD-PCR technique

Abstract Genetic diversity between fifteen commercial cultivars of rose were evaluated, using Ten decamer primers (A-J). All primers detected polymorphism among the cultivars. In total, 126 bands were produced, 73 of which were polymorphic. Primers E and F produced the highest, while primer H produced the lowest number of bands. The percentage of polymorphic bands ranged from 37% to 81% with an average of 63.9%. The average number of polymorphic bands produced was 7.3 per primer. Only the amplified DNA fragments ranging in size between 220 to 3000 bp were used for statistical analyses. Cluster analysis based on the presence or absence of bands was performed by Jaccard's similarity coefficient, based on Unweighted Pair Group Method with Arithmetic Averages (UPGMA). Genetic similarity ranged between 0.12 to 0.53. The dendrogram revealed two main clusters. Each cluster was divided into subgroups. This investigation showed that genetic diversity was relatively considerable among these cultivars. Also, the results propose that RAPD marker is a useful tool for evaluation of genetic diversity and relationships amongst different rose cultivars

The Effect of Plant Growth Regulators on Shoot Proliferation and Rooting of Crataegus Pseudohetrophylla Pojark. Via in Vitro Culture

Crataegus is a tree species from Rosaceae family with medicinal, ornamental and commercial utilizations. Effect of different concentrations of plant growth regulators on shoot proliferation of Crataegus pseudohetrophylla Pojark. via in vitro culture was studied using single node explants. The grown shoots were transferred to MS medium supplemented with different concentrations of cytokinins (BAP, KIN, 2iP and Zt) in combination with NAA in 30 treatments, with 3 replications and each replication included 5 explants. Data were recorded after 3 subcultures. For rooting, basal end of shoots were dipped into 300mg/l of IBA at different durations (0, 5, 10, 20, 30, 40, 50 and 60 minutes), then the dipped shoots were cultured on hormone free 1/2 VS medium. The results of analysis of variance showed that there were significant differences in all of the traits. Results indicated that the highest number of shoots (39.33) was obtained on medium containing 8 mg / l BAP plus 2 mg / l NAA. The highest shoot length (4.67 cm) and leaf size (3.73 cm) was achieved on 7 mg / l BAP plus 2 mg / l NAA and 2 mg / l Zt plus 1 mg / l NAA, respectively. The highest rate of rooting (33.33%) and root number (4n) were induced on shoots dipped for 40 minutes in 300 mg / l IBA