The Effect of Allelochemicals on Plant

GrowthA project by: Cody FrankoPeriod 10 Honors Biology

Problem and Hypothesis

Problem Statement: How will a plant’s growth be affected if it is

planted next to a sweet potato plant that releases high levels of allelochemicals?

Hypothesis: If a plant is planted next to a sweet potato

plant that releases high levels of allelochemicals, then the plant will not grow as efficiently.

Basic Concepts Allelopathy- The releasing of

secondary metabolic products into the environment.

Allelochemicals- chemicals that are released by volatilization in the form of edible tissues.

Ipomoea Batatas- the scientific name for a sweet potato plant. 

Basic Concepts Do the average garden plants release any

allelochemicals, if so than how much do they release?

What are the levels of allelochemicals released from a sweet potato plant?

How should I water the plants, as one or two separate?

Is there a set temperature the room should be while I grow these plants?

Procedure Plant all of the plants in the pots at different

distances. Use sweet potato plants for allelochemicals

and sunflower plant as average plant. Water daily with 150 mL of water Monitored growth

Design Diagram

Levels 5cm 10cm 15cm 20cm Control: not planted next to sweet potato plant

Trials 6 6 6 6 6

CONSTANTS: Same temperature water, same types of plants, same amount of sunlight, same soil, same amount of water.

Safety Precautions Do not consume plants or soil.

Do not “Play” with pots they might break!

ResultsControl 5 cm 10cm 15 cm 20 cm

Trial 1 14 7 7.5 9 11Trial 2 13 7 7 10 12.5Trail 3 13 9 8 6 12Trail 4 14 8 8 10 9Trail 5 12 10 8 10 13Trail 6 10 8 6 12 12Average Height

12.7 cm

8.1 cm 7.5 cm 9.5 cm 11.6 cm

Null Hypothesis Allelochemicals have no effect

on plant growth.

Anova TestANOVA: ResultsSource of Sum of d.f. Mean FVariation Squares Squares between 118.9 4 29.72 14.55error 51.08 25 2.043 Total 170.0 29

Significance of 0.00 Null can be rejected

Photodocumentation

Photodocumentation

Photodocumentation

Graph

ConclusionAllelochemicals do have an effect on plant growth.

Hypothesis was supported

Sources of Error Not exposed to enough Sunlight

Not enough time given for plants to grow

Inconsistent amounts of water

Improvements More trials

Done in warmer and sunnier conditions

More precise measurements

Extensions and Applications

Do experiment with different plant types like weeds and fruits

Useful for gardening techniques

Acknowledgements Mrs. Pietrangelo

My Mom

Bibliography Ferguson, James, and Bala Rathinasabapathi. "Allelopathy: How Plants Suppress

Other Plants." University of Florida, July 2003. Web. 5 Oct. 2010. <http://edis.ifas.ufl.edu/hs186>.

INDERJIT, and K. G. MUKERJI. Allelochemicals: Biological Control of Plant Pathogens and Diseases. Dordrecht: Springer, 2006. Print.

Kavassalis, Catherine. "Allelopathy for the Home Gardener." Halton HELPs. Web. 05Oct. 2010. <http://haltonhelps.org/Egardening/Allelopathy.htm>.

Harrison, Howard, and Joseph Peterson. Allelopathic Effects of Sweet Potatoes onYellow Nutsedge and Alfalfa 34.4 (1986): 623-27. Web. 5 Oct. 2010. <http://http:// www.jstor.org/pss/4044250>.

Hunter, Sheri. "Guidelines for Watering Indoor Plants." Guidelines for WateringIndoor Plants. 1 May 2010. Web. 5 Oct. 2010. <http://www.coopext.colostate.edu/4dmg/Plants/guidline.htm>.

Wolford, Ron, and Drusilla Banks. "Sweet Potato - Vegetable Directory - Watch Your Garden Grow - University of Illinois Extension." University of Illinois. Web. 05 Oct. 2010. <http://urbanext.illinois.edu/veggies/sweetpotato.cfm>.