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Ten common cultivars in Taiwan of poinsettia cvs. "Garden
cultivar","Annette Hegg Dark Red","Gutbier V-14 Red"," Annette
Hegg Diva Starlight","Eckespoint Lilo Red" , "Gross Supjibi","
Viner Star","Petoy" ,"Eckespoint Freedom", "PLA Jacobsen
Peterstar" were pollinated by cross or self each other in order
to discuss the reasons of low sterility and to select good
seedlings by the way.Pollens germination was affected by
temperature. Under the temperature of 15C , pollens did not
germinate. The optimum temperature for most of germination of
poinsettia pollen was at 23C. The successful pollination was
also around 23C. Pollen tube entered ovule after the 3-5th day
of a successful pollination.Not only had the highest pollen
germination rate but seeds harvested of poinsettia cultivars
occurred in "Garden cultivar","Eckespoint Freedom" and
"Eckespoint Lilo Red". On the other hand the lowest of that
occurred in "Annette Hegg Diva Starlight" and "Petoy". The worst
for breeding was on "Jacobsen Peterstar" ,it had few pollens and
the pollen did not germinate on style. Fruit setting rate was
2.3% and 136 seeds were obtained in the first year. Seeds
germination rate was 26% (including two from aseptic seed
culture) and 19 plants with good characteristics were selected.
Fruit setting rate was only 18% and 812 seeds were harvested in
the second year. The capsules and seeds appearance
characteristics were more similar to female parent than male
parent. For example "Eckespoint Freedom"×"Garden cultivar" the
capsules and seeds of next generation were similar to
"Eckespoint Freedom". There cross of red cv., "Garden cultivar"
×"Eckespoint Freedom", "Garden cultivar" ×"Cross Supjibi" or
"Garden cultivar"×"Garden cultivar", offspring with red or
white bracts. In the experiment,11 seedlings were selected from
offsprings which were pollinated in winter and sow in May.
Furthermore 8 seedlings were selected from offapring which were
pollinated in spring and sow in July.
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