Purple Sage vs California Poppy Scifair Projects

Purple Sage Oil

Purple sage oil has interesting properties. In this project its herbacidal properties are examined.

EDU 3020 Lemon Clock	Young Scientists Club Set 10	Young Scientists Club Set 5	Student & Home Microscopes
Ages 8 and up	Ages 9-12	Ages 9-12	Ages 10 to Adult

Objectives/Goals

My goal was to discover if oil in Purple Sage leaves is allelopathic and whether it inhibits the germination of the California Poppy or Fennel the most drastically. My objective was to either confirm or disprove the results of Cornelius Muller who was a prominent ecologist in the 1960s and believed strongly in allelopathy. My hypotheses were that the Purple Sage would prove allelopathic and the California Poppies would be less effected by the supposedly allelopathic oils due to possible adaptation since it is a native plant that grows in close proximity to sage. My goal was to, perhaps, find that by not clearing native chaperal, we could prevent the invasion of many nonative species.

Methods/Materials

Over the course of two trials I planted 1000 seeds (half Fennel, half California Poppy). My constant was the seeds I watered with distilled water and my variables were the plants treated with Purple Sage oil infused water, and for the second trial, nutrient enriched water. I made the allelopathic treatment by collecting Purple Sage and soaking it in water for a brief time to imitate rain falling through a sage canopy.

Results

I was very surprised with my results. The Purple Sage oil actually drastically benefitted the germination rate of my Fennel seeds and had no substantial affect on the California Poppies. After trial one, I hypothesesed the the increase germination could be due to nutrients in oils. However, after adding another treatment with nutrients for my second trial, I realized that the nutrients added actually lowered my germination rate. Moreover, I was unable to find any evidence of the controversial theory of allelopathy.

Conclusions/Discussion

Although in this experiment I was unable to prove the allelopathic affect, I believe there is still a good possibility it exists. For future experiments, I would test with volatile gases that some scientist believe plants emit. Also, I would limit the amount of water given to the seeds thus stressing them and perhaps causing them to demonstrate allelopathy for a competive advantage. There is much more research opprotunity in this area, because although allelopathy has been proven in labs, it is very hard to demonstrate in nature. 3rd party contributor