Previously, we showed that a reduction of FaTFL2 (homolog of Arabidopsis thaliana TFL1) expression is a key signal for flowering in domesticated octaploid strawberries (Fragaria ×ananassa). Since FaTFL2 expression seemed to be regulated by temperature rather than by photoperiod, we investigated whether down regulation of FaTFL2 and floral meristem generation occurred at different temperature conditions. In addition to the conditions for a normal super-forcing cultivation system of an 8-hour photoperiod and day/night temperatures of 31.2 or 30/15 °C, flowering also was generated under the same photoperiod and day/night temperatures of day/night-half/night-half temperatures of 30/15/25 °C conditions. We demonstrate that the new super-forcing cultivation system is energy saving based on the reduction of FaTFL2 expression.
Ryoichi Nakajima, Shungo Otagaki, Katsuhiro Shiratake and Shogo Matsumoto
Hiroaki Ito, Masaki Ochiai, Hiroaki Kato, Katsuhiro Shiratake, Daigo Takemoto, Shungo Otagaki and Shogo Matsumoto
We have succeeded in establishing a virus-induced gene silencing (VIGS) of rose using Apple latent spherical virus (ALSV) vectors. An ALSV infection on rose did not cause any symptoms like those observed on other plant species and grew healthy. We have cloned and sequenced the phytoene desaturase (PDS) gene in wild rose, then used its fragment for silencing the rose internal PDS gene. The silencing phenotypes such as the highly uniform photo-bleached phenotype with PDS inhibitions were observed on the upper leaves of primary shoots and on a secondary shoot of R. rugosa for more than 5 months. ALSV vectors seemed useful for analyzing gene function and for the molecular breeding of rose.