Studies On The Classification And Genetic Relationship Of Rosa Hybrida Minima

Morphology, Palynology and SSR analyses were made to study the genetic relationship of different Rosa hybrida minima cultivars in order to provide theoretical basis of cultivar classification, breeding, new variety breeding and molecular level study of Rosa hybrida minima. The results were as followings:1 The Rosa hybrida minima had beautiful type of flower and plenty of colors and the flower diameter is about 2-5cm. The accessions could be classified into two groups when similarity coefficient was 0.60 based on morphological traits. The first group included'White Koster','White pearl','Gold Sun','Korean','Romantic','Red cloud','Pink Koster','Winter Plum','Miss Sun','Rainbow','Purple times','Purple Ministar'which the flower diameter was less than 5cm and could be classified into different subgroup by flower color, such as'White Koster'and'White pearl'were white colored,'Korean','Romantic','Red cloud','Pink Koster'and'Winter Plum'were pink colored,'Miss Sun'and'Rainbow'were mixing colored. The second group included'Maddy','Fairy','Blue Pitter','Carat Lisa','Free gold'which the flower diameter was more than 5cm .'Maddy'and'Fairy'were classified into a subgroup which were red colored.2 Pollens of 10 Rosa hybrida minima cultivars were examined by LM (Light Microscopy ) and SEM (Scanning Electron Microscopy). The cluster analysis was carried out based upon the observation results. The pollen grains were tricalporate and 3-lobed circular in polar view. Different cultivars showed different exine sculpture and fringes,luminas and verrucate. The pollen shapes were spheroidal or super-spheroidal by P/E (Polar axis length / Equatorial axis length) criteria. The result of cluster analysis indicated that the cultivars could be classified into three groups when similarity coefficient was 0.37.The first group included'White Koster','Pink Koster','Purple Ministar','Romantic'. The second group included'Gold Sun','Maddy','Dwarf Fairy','Hula Girl','Winter Plum'. The third group included'Red Cloud'.3 25 Rosa hybrida minima cultivars were used for genetic relationship analysis by using simple sequence repeat (SSR). 46 alleles were amplified by using 16 pairs of primers selected from 23 pairs, of which average 2.9 alleles per pair of primer were amplified and calculation of the similarity coefficient and also cluster analysis showed that: The variance range of genetic similarity coefficient of SSR markers among the varieties were 0.4565-0.9783, and the gnetic distance were 0-0.9262.The cultivars could be classified into the 2 groups when similarity coefficient was 0.58. The first group included'Winter Plum'and'Purple Ministar'and the second group included'Charles self-expenser','Black Jade','Dwarf Fairy','Carbuncle','Purple times','Gold Sun','Strawberry swirl','Rebirth Glacier','Razzle','Clarissa','Blue Pitter','Sweet Dream','Snow','White Koster','Pink Koster','White pearl','Korean','Maddy','Freegold','Rainbow','Sunmaid','Small welfare'and'Red Cloud'.4 The Morphology, Palynology and SSR analyses classification results are proximately same,but there were also some differences.'White Koster','Pink Koster','Korean'and'Red Cloud'were classified into one group both by morphological classification and SSR technique, which showed there was closer relationships between them.'Purple Ministar','White Koster'and'Pink Koster'were classified into a group by morphological and palynological classification , while the result based on SSR technique showed there was a distant relationship from'Purple Ministar'to the other two cultivars. We should take them in consideration comprehensively to find the the genetic relationship of different Rosa hybrida minima cultivars and provide theoretical basis of cultivar classification, breeding, new variety breeding and molecular level study of Rosa hybrida minima.