Faculté des Sciences Agronomiques et Environnement, Programme de Maitrise, Université Evangélique en Afrique, U.E.A./Bukavu, Bukavu, Sud Kivu, RD Congo
In the perpective of enquiring the state of the plantations phytosanitairy of coffee tree of the North Kabare in order to undertake the averages ways of fighting (preventive, curative or integral) able to grow up the coffee production in the science subjects in the South Kivu coffee tree a study for evaluation the phytosanitary state of coffee plantations in the region of Kabare the North has been done. At the end of the study, it has noticed that the anthracnose, the rust, the die-back and the sigatoka even the thrips unwrapping, the drawing pin coffee tree, the dentals drawing pin, the rongers leaves catapillar, the pyral of drupes and the coffee tree hannetons are respectively the illnesses and the found insects in the coffee plantations of the North Kabare but with the incidence relatively different. The anthracnose's rate incidence has been very highest (33%), followed by the coffee trees rust (30%) than the sigatoka (22%) and at the end die-back (15%). As far as ravagers are concerned, the drawing pin of coffee tree presented a relative incidence the highest of 32% of order, followed by the unwrapping thrips (15%), and the coffee tree hannetons (14%), of rongers leaves catapillar (14%), of pyral of drupes (13%) and at the end of dentel drawing pin (12%). All the coffee trees of the region of the North Kabare are old in the way that their ages vary between 43, 1 years and 69 years with 57, 5 years of average.
In an attempt to find non-harmful to humans and does not pollute the environment, effective tack against the coffee and alternatives to synthetic pesticides polluters of the environment, an in vitro test of activity biodegradable organic substances insecticides, insecticide alkaloids, steroids, saponins and isolated Capscicum frutescens L. terpenes was performed in the presence of synthetic pesticides (Supadip and Dimethoate) and water as controls. Mortality tack the coffee very varied significantly depending on the treatment, concentration as well as the interaction of treatment and concentrations of insecticides tested substances. The insecticidal activity of Supadip was superior to all other insecticides tested at doses of 0.01ml / l and 0.1 ml / l (100% mortality) at the dose 0,636g / l, the alkaloids have Capsicum similar to that of Supadip and dimethoate (100% mortality) effect. Steroids have a mortality of 57% at the dose 0,636g / ml saponins and terpenes have a minimum effect to said dose. Dimethoate was inactive at doses 0.1 ml / l and 0.01ml / l. Alkaloids have low lethal dose LD50 (0.21