| Budget Amount *help |
¥4,030,000 (Direct Cost: ¥3,100,000、Indirect Cost: ¥930,000)
Fiscal Year 2015: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
Fiscal Year 2014: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000)
Fiscal Year 2013: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000)
|
|---|
| Outline of Final Research Achievements |
Viroids are the smallest and simplest of the plant pathogens, consisting of a single-stranded circular, naked RNA genome from 246 to 401 nucleotides (nt) in length, which lacks any protein-coding sequences. To identify the major pattern of seed transmission of viroids, we used in situ hybridization to histochemically analyze the distribution of Potato spindle tuber viroid (PSTVd) in each developmental stage of petunia (flowering to mature seed stages). Our observation that PSTVd infected reproductive tissues such as the ovule before embryogenesis reveals that PSTVd can invade the embryo through pollen (i.e., seed transmission of PSTVd occurs by indirect embryo invasion through the infected embryo sac or pollen). These findings indicate that PSTVd is indirectly delivered to the embryo through ovule or pollen during the development of reproductive tissues before embryogenesis but not directly through maternal tissues as cell-to-cell movement during embryogenesis.
|
