Question

1
The Effect of High Concentrations of GA3 and Seed
Age on Germination of Silene latifolia Allison
Amore, Meredith Harry, William Wood Department of
Biology, Davidson College
Age Decreases Viability

• Question
• Do increased concentrations of GA3 and/or seed
  age affect germination in Silene latifolia?
• Background
• White campion, (Silene latifolia or Silene alba)
  - dioecious, perennial plant, native to Europe
• - excellent model species to study the dynamics
  of a fragmented plant populations (McCauley,
  1994)
• Builds and maintains seed banks (Peroni and
  Armstrong, 2001)
• Researchers need effective way to break seed
  dormancy
• GA3 naturally occurring plant hormone
• - promotes intake of cell wall hydrolases and
  weakens thick cell
• layers of endosperm
• - allows radicle to emerge from the seed coat
  (Leubner, 2003)
• Previous study indicates increasing GA3
  concentration increases mean fraction germination
  (Bio 341, Spring 2002, unpublished data)
• Methods
• 1000 seeds obtained from 2002 and 2003 seed crops
  from same population
• Groups of 50 seeds randomly assigned to treatment
  in Petri dish

• Conclusions

Fig 3. Mean seeds viable. Error bars 1se N5
reps/GA3 treat/year with 50 seeds per rep
GA3 Increases Germination of Viable Seeds

Fig 4. Mean germination of viable seeds. Error
bars 1se N5 reps/GA3 treat/year with 50 seeds
per rep
Treatment Concentration of GA3
Control Distilled water
Low 2.601 X 10-3 M
Medium 1.170 X 10-2 M
High 2.601 X 10-2 M

• Results

GA3 Increases Germination
Table 1. Description of treatments.
Fig 2. Mean fraction germination of all seeds.
Error bars 1se N5 reps/GA3 treat/yr with 50
seeds per rep
Fig 1. 60mm Petri dish with 50 seeds on
saturated filter paper