Comparing tissue cultured and traditionally propagated roses in the greenhouse.

Roses (Rosa hybrida L.) are among the most attractive flowers around the world, used as garden plants, cut flowers and pot plants; from which cut roses have extensive economical value. Rose plants are propagated by seed, stem cutting, grafting, budding, cutting-graft (stenting), cuttingbudding, root grafting and tissue culture. In Iran, greenhouse rose culture has recently increased. Rose plants are usually imported from Netherlands, which is expensive. This comparative study was conducted to evaluate quantitative and qualitative characters of three rose cultivars ('Dolce vita', 'Avalunch' and Full House) propagated by traditional method (imported from Netherlands) , tissue culture (own rooted) and tissue culture (grafted on Rosa canina L. rootstock) in soilless media. The statistical design was arranged as factorial in a completely randomized design (CRD) with three factors propagated method (traditional, tissue culture own rooted and tissue culture grafted on rootstock) and three time of harvests with ٥ replications. To obtain uniform plants, the rose bushes were pruned and bended (kept two buds on each plant). Fresh and dry weight, length, leaf number, leaflet number, stem diameter, number of nodes and internodes of the flowering stem, bud diameter, bud length, fresh and dry weights of flowers and also leaf cholorophyll content, leaf area, quality index, flash to flash and vase life were recorded three times. The result indicated that in most attributes there were significant differences between the three propagation methods. Tissue culture (own rooted) and tissue culture (grafted on R. canina) had healthier growth than traditional propagated roses in most of the traits (fresh and dry weight of the flowering stem, diameter and length of the flowering stem, leaf number, leaf area, node number, bud diameter, bud length, fresh and dry weight of flower, petal number, leaf chlorophyll content, flash to flash and vase life). Traditionally propagated roses had higher quality index and fresh weight in 'Dolce Vita', length of internodes in 'Avalanch' and quality index in 'Full House' but the means were not significant. The effect of propagation method on flower length, node number, leaf number, leaflet number and quality index were not significant. Results of the present investigation showed the superiority of tissue cultured roses, whether on their own roots or grafted on rootstock. Since the superiority was observed in commercial characteristics which are important in cut flower production, therefore propagation by tissue culture method is recommended for the three genotypes studied. However, rose plants are highly heterozygous, thus further researches on other cultivars is suggested.