Alternating Temperature Germination

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Alternating Temperature Germination

• Germination of White Snakeroot

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White Snakeroot

• Eupatorium rugosum
• North American herb
• Poisonous
• Grows up to 1.5 meters tall
• Has 18cm leaves

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White Snakeroot

• Contains a toxic alcohol
• causes muscular tremors, weakness, and
  constipation leading up to death
• Causes milk sickness in humans
• infected human vomits and is comstipated
• Boneset tea is a folk remedy for the fever
• Produces seeds in August

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White Snakeroot Seed Germination

• Seeds are produced in the fall
• go through a dormancy-nondormancy cycle
• conditional dormancy
• Seeds germinate only under a limited range of
  environmental conditions.
• An adaptation to seasonally unfavorable
  environmental conditions.
• Alternating temperature is the environmental
  signal

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Experiment 1

• This experiment is to break dormancy using
  alternating temperatures
• The experiment is to also find the optimum
  number of cycles to achieve 100 germination
• There are two controls, one getting only cold and
  one only warm

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Experiment 1

• Each dish contain 50 seeds, filter paper and 3ml
  of water.
• One cycle is 12 hours in a refrigerator and 12
  hours at room temperature
• The dishes received 1-6 cycles
• After the cycles, the dishes were allowed 3 days
  germinating time.

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Experiment 1
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Results

• The graph shows that dish 3 has the best output
  and rate of germination.
• Dish 3 had three cold and warm treatments
• Its germination was closest to 100
• Dish 6 has the worst overall performance.
• lowest output and rate
• extra cold treatments possible hindered
  germinaton

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Results

• Dish 2 has the second best, eventually catching
  up with Dish3.
• The warm and cold controls showed little to no
  growth.
• This shows that alternating temperatures plays
  some role in this plants germination.

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Experiment 2

• The test was run a second time to enhance the
  results of experiment 1
• 14 dishes were used
• 5 were given 1-5 cycles, 3 days germintion
• 4 were give gibberrillic acid, a germination
  inducing agent, and exposed to just room
  temperature
• 5 were given GA, 1 cycle and allowed to germinte
  3 days

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Experiment 2

• After 3 days of treatment, the GA and room
  temperature dishes were low in germination
  compared to dishes with the GA and cycles
• After the first day of counting the two low GA
  and two low GA and cycles were given another
  cycle.
• They were recounted on the fifth day, allowing 3
  days germintion

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Experiment 2
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Results of Experiment 2

• The dishes receivimg the normal 1-5 cycles were
  similar to the data in experiment 1 on the first
  day.
• 2 and 3 were equal The dishes receiving the 1-5
  normal cycles showed similar in their initial
  germination
• The dishes with just GA and room temperture
  showed low germintion
• The dishes with GA and cycles reached optimum
  germintion
• The four that received another cycle doubled
  their germination from the first day.

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Conclusions

• From the data collected, it is concluded that 3
  cycles, each with 12 hours of cold and warm
  produces optimum germintion
• This plant uses this type of germination because
  of the climate condtions of this area.
• Fluctuating tempertures are a signal of spring in
  the Ohio River Valley

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The End

• Thank You!