Study the relationship between yield and flower yield components in Rosa damascena Mill. genotypes of Rosa damascena Mill

In order to evaluate the relationship of flower yield per plant and yield components in Rosa damascene Mill., an experiment was conducted in a Complete Randomized Block Design with three replications and with 35 genotypes of Rosa damascena, in Kashan dry land and desert research station. Fourteen characters of morphological and yielding were measured. Flower yield per plant exhibited a significant positive correlation with fresh weight of flower, flower yield per branch, number of flower per branch and plant height, but with bud length had a significant negative correlation. Result of stepwise regression analysis for flower yield per plant showed that fresh weight per flower and number of flower per plant entered the model, respectively, and justified 90 percent of total variation of flower yield per plant. Factor analysis revealed 5 factors which justified 83.2 percent of the total variation among characters. In the first factor, traits of number of flowers per branch, flower yield per branch, canopy diameter, number of flower per plant, length of receptacle and flowering time had greater loadings and was named flower yielding factor. Path analysis showed that number of flower per plant, fresh weight of flower and flower yield per stem had the highest direct effects on flower yield per plant, therefore, this research suggest the number of flowers per plant, fresh weight per flower and number of flowers per branch can be good selection criteria for improving flower yield per plant in Rosa damascene.