The Feasibility Study on the Prediction of Ploidy Levels Base on Pollen Dimensions in Rosa

Ploidy level is one of important factors for plant breeders; therefore models that can predict it are very practical. To estimate of ploidy levels in some species, hybrids and cultivars of Rosa, dimensions of over 500 pollens include pollen length, width and area measured at ABRII. The calculations were carried out in several stages. First, Ploidy levels were regressed with pollen dimensions, after that, pollen area was regressed with pollen length and width. Finally the best models from previous step were tested to estimate of pollen level. In the present study, although a highly positive correlation (r2 ?0.80, except for 2x) was obtained between pollen length and pollen area, but to predict of ploidy level, the correlation between it and pollen demotions was very weak (r2 ?0.24). Results of test the best models (with highest r2 and lowest SES) for estimating of ploidy level, despite could be used, but because of the strong correlation among them, were not reliable.