1. P3.5 The Effect of Liquid Smoke on Different Plant Species Zachary Beck Department of Biological Sciences, York College of Pennsylvania, York, Pennsylvania Introduction: The compounds in smoke and extracts of smoke can regulate seed germination, but the isolation and characterization of these compounds remains elusive (Flematti 2004, Jain 2007). Flematti (2004) and Jain (2007) noticed that in arid regions where destructive wild fires are prevalent, like California and South Africa, there are certain populations of plants that recover quickly via enhanced seed germination. These plant populations recover before the soil has fully cooled (Flematti 2004, Jain 2007). This increased germination rate is linked to compounds that are found in smoke. The compound that was found by Flematti (2004) that increases the germination rate is the butenolide 3-methyl-2H-furo[2,3-c]pyran-2-one. This compound is produced via cellulose combustion. It is effective with or without fire. Jain (2007) found that this butenolide increases the germination rate of the tomato Solanum esculentum. In Jain’s (2007) research the butenolide was used as a seed-priming agent for Solanum esculentum. Jain’s (2007) research showed that S.esculentum not only showed increased germination but increased tolerance towards stress in this species. The same germination cues that are found in smoke are also found in the common food condiment liquid smoke (Baldwin 1994). Baldwin (1994) tested the compounds found in liquid smoke on populations of Nicotiana attenuata, a native tobacco plant in the western United States, and found it to affect different factors of germination. This led to the inspiration of my research, in which I set out to investigate liquid smoke’s abilities in other agriculturally important plants. I tested liquid smoke to assess whether it would increase germination rates as well as the mass, as a measure of vigor, for tomatoes (Lycopersicon esculentum, var. beefsteak), watermelons (Citrullus lanatus, var. Crimson sweet), pumpkins (Cucurbita pepo, var. Connecticut field), and green peppers (Capsicum annuum, var. California wonder). Overall Goals:  Test if liquid smoke increases the germination rate of green peppers and tomatoes.  Test if liquid smoke affects the mass of seedlings from the Solanaceae family (tomatoes, green peppers), and the Cucurbitaceae family (pumpkins, watermelons), two families of common garden vegetables.  50 tomato and 50 green pepper seeds were planted in soil and treated with 0 (control), 15%, 30%, 45% concentrations of liquid smoke.  Number of seeds were counted each day for 8 days; percent germination was calculated out of 50 for each day.  Tomato, green pepper, watermelon, and pumpkin were then planted in soil and treated with 0 (control) and 30% liquid smoke and allowed to grow.  10 plants were collected every week for four weeks, and dried in an oven for 24 hours.  Seedling vigor was measured as the mean dry mass of seedlings (n =10 ) for each week.  Differences in germination rates were analyzed by regression on arcsine square root transformed percent germination. Differences in seedling biomass were analyzed using regression analysis on seedling dry weight. Methods: Results: Conclusions:  Plants treated in all concentrations of liquid smoke germinated sooner than those not treated with liquid smoke.  By eighth day all had germinated no matter the treatment.  The biomass of the plants did not significantly differ between those treated with water and those treated with liquid smoke. References: Baldwin, I. T., Staszak-kozinski, L., and Davidson, R. 1994. Up In Smoke: I. Smoke- Derived Germination Cues for Postfire Annual, Nicotiana attenuate Torr. Ex. Watson. Journal of Chemical Ecology. 20: 9: 2345-2371. Flematti, G. R., Ghisalberti, E. L., Dixon, K. W. and Trengove R. D. 2004. A Compound from Smoke That Promotes Seed Germination. Available from: www.scienceexpress.com. Accessed 2007 November 20. Jain, N. and Van Staden, J. 2007. The potential of the smoke-derived compound 3- methyl-2H-furo[2,3-c] pyran-2-one as a priming agent for tomato seeds. Seed Science Research 3:175-181. Acknowledgements: I would like to thank Dr. Karl Kleiner, PhD, as he assisted me in the design of my experiment, and helped assist throughout the work. Figure 1: Germination rate of tomatoes using arcsine square-root transformed data. Slopes of regression lines do not differ (P = 0.91). Regression lines not shown for clarity. Figure 2: Germination rate of green peppers using arcsine square-root transformed data. Slopes of regression lines do not differ (P = 0.96). Regression lines not shown for clarity. Figure 3: Relationship between time and biomass (dry weight) for tomatoes. Slopes of lines do not differ (P = 0.73). Each symbol is x ± 95% C.I., n = 10. Figure 4: Relationship between time and biomass (dry weight) for green peppers. Slopes of lines do not differ (P = 0.56). Each symbol is x ± 95% C.I., n = 10. Figure 5: Relationship between time and biomass (dry weight) for pumpkins. Slopes of lines do not differ (P = 0.18). Each symbol is x ± 95% C.I., n = 10. Figure 6: Relationship between time and biomass (dry weight) for watermelons. Slopes of lines do not differ (P = 0.58). Each symbol is x ± 95% C.I., n = 10.