To select superior rose rootstocks from local wild populations of Row multiflora, twelve local populations were collected throughout the country and four foreign cultivars were introduced. In provenance test, each population was evaluated and classified by the single link cluster analysis based on the Mahalanobis´ distance and electrophoresis of isoperoxidase in genie level. In addition, basic investigations were also performed to select superior populations for rose rootstocks. The results are summarized as follows :
1. In single link cluster analysis by the Mahalanobis´ distance(D²), the population groups based on 13 characters were most distinctly classified in comparison with the groupings based on eleven, nine, seven and four characters in consideration of the rank of habitability. However, the classification pattern of local populations and cultivars based on 11 characters after removing two characters, the new shoot color and leaf length having low habitability, was similar to that of 13 characters due to small coefficient of variation of intra-groups. It seemed impossible except a special case to use the four characters such as the angle of branch, leaf thickness, growth status and the degree of powdery mildew occurrence which are highly correlated with powdery mildew resistance, for classification of populations due to wide range of coefficient of variation in other characters.
2. The average values of inter-group D² were greater than those of intra-group D².
3. with an exception of a few populations, local populations were mostly grouped by geographical distribution low latitude southern group, Gyeongsang province group and near Gyeongsang province group. Introduced cultivars formed quite different groups of which genetic distance were far from those of local populations.
4. The group VI which consisted of Pyeongchang, Jecheon and Jeju populations might be considered a group having the most racial characters.
5. Among 13 characters, rite angle of branch, the number of branches and thorns, and plant height having relatively high habitability were the main contributors to the inter-group D², whereas Leaf length and the range of new shoot color were minor ones.
6. In general, intra-group D²s were highly affected 6y the angle of branch, growth status, leaf thickness, plant width and the number of leaves. How-ever, some differences were observed among the groups.
In isoperoxidase zymograms obtained by starch gel electrophoresis of the mature leaves, six bands were observed. Band A was observed in all samples, whereas the occurrence of other bands were inconsistent showing some variation. The results of variations and number of bands were summarized as follows :
1. The inter-group variations were greater than those of intra-group. The variation differences among local populations or cultivars were ascertained by the analysis of variance.
2. The local populations were classified into five groups by the single link cluster analysis based on the Mahalanobis´ D² computed using the number and freqaency of isoperoxidase bands, and into seven groups when both twelve local populations and the four introduced cultivars were included.
3. Although some exceptional populations were observed in certain circumstances, a similar group classification was obtained from both the single link cluster analysis based on D² computed from isoperoxidase zymogram and the morphological classification with nine characters.
4. The average values of inter-group D²s were always greater than those of intra-group, and the introduced cultivars showed the farthest distance from the groups of local populations.
The results obtained from the basic studies for the selection of superior rose rootstocks are summarized as follows:
1. The characters having high habitability were the angle of branch, plant height, growth status, and leaf width, and those with low habitability were the color of new shoot and leaf length.
2. Sixty-six out of seventy-eight character combinations gave high correlation coefficients significant at the 5% level of type I error.
3. Powdery mildew resistance was positively correlated with the angle of branch, the number of branches and thorns, and the range of new shoot color, whereas it was negatively correlated with leaflets, growth status, lent area and leaf thickness.
4. Although some populations gave different correlation coefficients from location to location, the characters which gave particularly high correlation coefficients acre leaf width, the angle of branches and the number of thorns.
5. The percentage of rooting and graft-compatibility were also variable according to the populations. Populations from Jeju, Jecheon, Pycongchang and Hadong were excellent for asexual propagation.
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