|Legaspi, Jesusa - Susie|
Submitted to: Subtropical Plant Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/24/2007
Publication Date: 8/15/2007
Citation: Legaspi, J.C., Gardner, C., Queeley, G., Leppla, N., Cuda, J., Legaspi, B. 2007. Effect of organic and chemical fertilizers on growth and yield of hot pepper, and insect pests and their natural enemies. Subtropical Plant Science. 59:75-84. Interpretive Summary: Florida is one of four major vegetable producing states in the United States. Bell pepper is the second most important vegetable crop in Florida and many producers of bell peppers have a significant acreage of hot peppers. The latter is increasingly becoming the favored choice in seasonings which are mainly supplied through imported products. In north Florida, resource-limited producers are beginning to find a viable niche-market in producing hot peppers. Scientists at the Center for Medical, Agricultural, and Veterinary Entomology, and collaborators located in Tallahassee, FL, studied the effects of using organic soil nutrients (poultry manure and mushroom compost) vs. chemical fertilizer on plant growth and yield in two varieties of hot pepper, 'Scotchbonnet' and Caribbean Red'. In addition, the populations of insect pests and their beneficial natural enemies were measured throughout the season. Plant growth was better in the field plots treated with poultry manure in the Scotchbonnet variety. The plots with a chemical fertilizer had the least plant growth in the Caribbean Red variety. There were no differences found in the numbers of peppers harvested in the plots treated with organic vs. chemical fertilizer. The main insect pests collected in the field plots were silverleaf whitefly, green peach aphid, bandedwinged whitefly and the western flower thrips. The natural enemies were identified as ladybugs and hover flies. The insect pest numbers were very low in the field throughout the season, perhaps due to the natural enemies, such that the use of chemical insecticides was not warranted. Hot peppers may be a viable niche crop in Florida for small growers because they seem to require relatively little maintenance, and further research will be carried out to improve yield and lower costs.
Technical Abstract: The effects of organic fertilizer on crop growth and insect pests were studied for two species of hot pepper (Capsicum chinense Jacquin (Solanaceae)): "Scotch Bonnet" and "Caribbean Red" in north Florida. The hot peppers were grown under three treatments: poultry manure; mushroom compost; or "Growers' Practice", (conventional pesticides and fertilizers), where equivalent amounts of soil nutrients were applied to all treatments. The Growers' Practice treatment permitted use of conventional insecticides should insect levels exceed economic thresholds. Results showed that plant height and canopy diameter were significantly higher in the poultry treatment in Scotch Bonnet. The Growers' practice treatment resulted in lowest plant height in Caribbean Red. Yields also were not significantly affected by treatments in either variety. Predominant pest insects found were the silverleaf whitefly, Bemisia argentifolii Bellows and Perring (Homoptera: Aleyrodidae); the green peach aphid, Myzus persicae (Sulzer) (Homoptera: Aphidae); the bandedwinged whitefly, Trialeurodes abutilonea (Haldeman) (Homoptera: Aleyrodidae); and the Western flower thrip, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae). Significantly more pests were found on Caribbean Red than on Scotch Bonnet, but in no treatments did pests reach economic injury levels. Results indicate that hot peppers may be a viable niche crop in Florida because insect pests do not appear to be significant. Furthermore, the crops may be grown using organic fertilizers because no benefit is obtained in the use of synthetic organic fertilizers.