This experiment aims to increase sweet pepper production sustainably by using manures and a combination of manure and fertilizer. Manures are well known to improve soil health and maintain crop production for a relatively long period. This study was conducted under a tunnel house at the National Agricultural Research and Extension Institute at Mon Repos East Coast Demerara, Guyana. Plots were arranged according to strip plot design with two treatments (Aristotle and Sunsation), four rates (R1: 0 g/plant), (R2: 350 kg NPK/ha + 10 t vermicompost/ha), (R3: 10 t poultry manure/ha + 10 t vermicompost/ha and (R4: 350 kg NPK/ha + 10 t poultry manure/ha) and replicated thrice. These nutrients were applied in a split application at four weeks before planting, and four, eight, and twelve-week intervals after planting. The varieties did not differ from one another for the vegetative parameters tested. Plants treated with Rate 2 achieved significantly better growth parameters such as plant height, plant spread, and number of branches than the other rates. Sunsation obtained a significantly higher yield of 21.4 t/ha at the 5% level as compared to Aristotle (19.9 t/ha). The various rates recorded significant differences in yield. Rate 2 obtained a significantly higher yield of 32.8 t/ha followed by Rate 4 with 24.9 t/ha, then Rate 3 (17.0 t/ha). The lowest yield of 7.8 t/ha was attained by Rate 1. The interaction of varieties and rates showed statistically significant differences in yield. The interaction of Sunsation and Aristotle with Rate 2 achieved a superior yield of 34.8 t/ha and 30.7 t/ha respectively than other rates. Rate 4 also obtained significant interaction with Sunsation and Aristotle to achieve a yield of 25.7 t/ha and 24.1 t/ha respectively than Rate 3. Rate 3 interacted significantly with Sunsation and

The aphid, Doralis symphyti (Homoptera: Aphididae), a harmful pest of many crops, causes direct damage by consuming all plant parts, reducing plant vigour, and indirect damage by honeydew secretion and transmission of several viruses. Due to the problem of pesticide resistance, alternative techniques for chemical control, such as the use of natural insecticides with minimal effects on the environment and natural enemies also coincide with organic agriculture have been the objective of this research. The effects of Mammea (Mammey americana) leaf extracts on the mortality of aphids were evaluated. The mammey extracts (Crude and refined) were tested in the laboratory (bioassays) at 100%, 90%, 80%, 70% and 60% dilution. The 80% was determined to be the most efficient dilution. The refined extract resulted in 100% mortality at 84 hours while the dry leaf and green leaf extracts gave 100% mortality in 96 hours. In the field, the refined extract resulted in 65% mortality, dry leaf crude extract obtained in 43% mortality and the green leaf crude extract gave 25% mortality. The mamey leaf extracts were efficient against the aphid in the laboratory since 100% mortality was obtained for all treatments. The field study found that the green leaf extract obtained 29% mortality, dry leaf extract achieved 47% mortality and the refined extract attained 63% mortality of aphids.