Similar to the results of this study, their tests found that horse and mink manure resulted in the greatest improvement in plant growth. However, Muenchang and associates (2006) found the sugar mill by-products improved the nitrogen fixing ability of plants by encouraging the development of certain bacteria on the roots. There are many field trials that are similar to those conducted in this study. Tuber yield and size were not affected significantly by the application of straw mulch on potatoes (Doring, et al., 2005). However, La Mondia and associates (1999) found that straw applied to potatoes increased yield in tubers exposed to certain potato pathogens. High concentrations of compost were found to improve plant growth, but reduce dry mass in sorghum (Harini, Rupela, & Reddy, 2006). Citius pulp was found to reduce the incidence of root and crown rot in peppers (Kim, Nemec, & Musson, 1997). This may be due to the effect of pH on microbial growth.

Environmental factors play a significant role in field trial results. Rainfall was found to be a greater factor in cow-pea trials than the application of dairy cow compost (Muir, 2002). The application of dairy manure in legume field trials did not improve yields, but increased crabgrass competition (Nguluve, et al., 2004). This is an important factor that may effect the practical application of these results. This study was conducted in a simulated environment and is it not known if these findings will carry over into the field.

Conclusion

The results of this study indicate that only hypothesis one holds true. The application of manure to soil produced a slight improvement over the other amendments. Sugar seemed to decrease plant production and yield. In order to come to a conclusion, in this case, one must consider these findings in relation to the body of...

Field and lab results varied regarding the results of various applications of compost amendments. Manure stood out in many trials as a superior soil amendments. However, it must be cautioned that rainfall and local conditions can significantly effect the results obtained.
References

Doring, T., Brandt, M., Heb, J., Finckh, M., & Saucke, H. (2005). Effects of straw mulch on soil nitrate dynamics, weeds, yield and soil erosion in organically grown potatoes. Field Crop Research, 238-249.

Hameeda, B., Harini, G., Rupela, P. & Reddy, G. (2006). Effect of composts or vermicomposts on sorghum growth and micorrhizal colonization. African Journal of Biotechnology. 6 (1), 9-12.

Kim, K., Nemec, S., & Musson, G. (1997). Control of Phytophtora root and crown rot of bell pepper with composts and soil amendments in greenhouse. Applied Soil Ecology. 5, 169- 179.

La Mondia, J., Gent, M., Ferrandino, F., & Elmer, W. (1999). Effect of compost amendment or straw mulch on potato early dying disease. Plant Disease. 83: 361-366.

Levy, J. & Taylor, B. (2003). Effects of pulp mill solids and three composts on early growth of tomatoes. Bioresource Technology. 89, 297-305.

Muenchang, S., Panichsakpatana, S., & Weaver, R. (2006). Tomato growth in soil amended with sugar mill by-products compost. Plant and Soil. 280, 171-176.

Muir, J. (2002). Hand-Plucked forage yield and quality and seed production from annual and short-lived perennial warm-season legumes fertilized with composted manure. Crop Science. 42, 897-904.

Nguluve, D., Muir, J., Wittie, R., Rosiere, R., and Butler, T. (2004). Yield and nutritive value of summer legumes as influenced by dairy manure compost and competition with crabgrass. Agronomy. 96 (3), 812-817.