Studies on Breeding in Chrysanthemum, Chrysanthemum morifolium RAMAT
I. Self-Fertility
1977 Volume 46 Issue 1 Pages 101-112
Details
1977 Volume 46 Issue 1 Pages 101-112
(1) As a part of breeding research on the chrysanthemum species, self-pollination was made with 57 cultivars and 2 wild species for the purpose of investigating self-fertility.
(2) Plants (cultivars and wild species) used as parent in this experiment were self-incompatible. The self-incompatibility, however, varied with cultivating year or the flower head even for the same cultivar. Some parental plants exhibited a high degree of self-fertility which might result from physiological factors.
(3) In self-pollinated progenies (S1, S2) the self-incompatibilities were almost the same as for parental plants. Some S1 plants such as the KB line obtained from cv.‘Katanozakura’, however, displayed an exceptionally high degree of self-fertility (KB 2; 52.32%, KB 6; 37.59%). This may have resulted from not only physiological but also genetic factors.
(4) Based on a critical survey for the existence of apomixis, it is concluded that such modes of reproduction are not observed in the S1 (KB line).
(5) A self-pollination was made with cultivars under three different conditions; that is, in the field, in pots or with cut-flowers. Field and pot plants displayed more or less higher fertility than was generally observed for cut-flowers.
For some cultivars, however, the fertility for cut-flowers was as high as or higher than for the other conditions.
(6) From the results of self-pollination made in tubulous flowers or ray flowers of nine progenies of the KB line, it was evident that self-fertility was higher for tubulous flowers than for ray flowers.
(7) A comparison was made between the stainability of pollen with aceto-carmine and the seed setting rate by self-pollination for the purpose of making clear the effect of pollen activity on self-fer tility.
In cv.‘Aztec’, Kogiku(G), KB 2 and KB 6 both self-fertility and pollen stainability were high. In the other cultivars and inbred lines, however, no relation was observed between them.
(8) The pollen germination rate on a medium containing 25% sucrose, 10ppm boric acid and 100ppm testosterone, and pollen stainability with nitro blue tetrazolium were examined in order to make clear the relation between pollen activity and high self-fertility for the KB line.
It was not possible to find any correlation between them.
