Study of correlation and cluster analysis of seed germination characteristics in 5 cultivars of Phalaenopsis orchid in Chen medium

Nowadays, in vitro techniques are proposed for commercial and rapid propagation of Phalaenopsis species. The present study aims were investigating the quality of seed germination of 5 cultivars of Phalaenopsis orchid, and correlation of their traits in the culture medium. The study was conducted using the green and ripe seeds in terms of 5 cultivars of orchid as Dubrovnik, Memphis, Andorra, Bucharest and Nottingham in a factorial experiment based on a completely randomized design. The capsules were formed using self-pollination of flowers in each cultivar. The green seeds were harvested at the stage of completely formed capsules and the ripe ones were harvested at the stage of initial browning of the capsule shell. The seeds were cultured on Chenchr('39')s culture medium. The number of germinated and non-germinated seeds were counted 18-33 days after their culture. The following factors were measured for each treatment: germination percentage, germination rate, germination index, mean daily germination, mean germination time and coefficient of germination rate. Correlation coefficient of %98 between the measured characteristics indicated a significant correlation between germination rate and germination index. The results of cluster analysis that was conducted based on all the measured germination characteristics showed the maximum mean distance between clusters; ultimately, that separated into two groups at Euclidean distance of 1.25 which Dubrovnik and Memphis cultivars were classified in the first group and Andorra, Bucharest and Notingham cultivars were classified in the second group. The key characteristics in separating cluster among the groups were considered to be germination percentage, germination rate, germination index and mean germination time. Discrimination function analysis test confirmed the grouping among the cultivars in a 100% manner. Both Hoteling-Lawley Trace as well as Roychr('39')s Greatest Root tests showed the highest value of 5.23 to confirm the grouping. It is concluded that using cluster analysis and correlation coefficient Notingham had the highest value in germination factors based on the germination percentage, germination rate and germination index which were regarded as key traits for the breeding programs.