This study was done with the objective of evaluating the agronomic performance of five varieties of forage grasses introduced to the community of Carmen Pampa in the province of Nor Yungas, La Paz from 2005-2006. The average temperature during the study was 11.93ºC and the average precipitation was 801.75 mm. The trial was done with a design of randomized blocks having five species and six repetitions. The species studied were: Panicum virgatum, Sorghastrum nutans, Andropogon gerardii, Tripsacum dactyloides, and Eragrostis curvula. Variables evaluated were: plant height (cm), coverage (%), number of plants, bunches of florets, and dry matter yield (kg/ha). The forage species that grew highest were Eragrostis curvula (55.5 cm) and Panicum virgatum (44.96 cm). Those same species also showed the best performance in regard to coverage with 88% and 33.4%, respectively. Eragrostis curvula had the largest number of plants with an average of 72.5 plants per m2. With regard to bunches of florets, Eragrostis curvula had the most with 31.33 bunches. As for dry matter yield, Eragrostis curvula had the best performance with 5298.5 kg/ha.

In Bolivia, tomato acreage is 6717 and has a yield of 12005 kg/ha and the total production is 80,636 TM. Departments that harvest tomato are Santa Cruz, Cochabamba and La Paz, Santa Cruz being the department that shows the highest rates of production with 40653 TM in comparison with La Paz which has a production of 3109 TM and Cochabamba of 2420 TM. The principle factors in affect are, the best climatic conditions in Santa Cruz, while Cochabamba and La Paz have differences in seasonal changes (National Institute of Statistics, 1998). The importance of the tomato harvest lies in consumption preference, for the nutritional properties, as they provide a rich source of Vitamins A and C, principally for its qualities of high productivity in terms of yield per area, being a factor of great importance in the economy of the farmer. The repeated production of tomato in the same area or locality tends to create problems phytopathologicals caused by fungi, bacteria and viruses, that at times become difficult to handle, thus becoming serious limiting factors that are able to seriously affect the yields, as such the investigation of sickness control is of extreme importance. The community of Carmen Pampa belonging to the municipality of Coroico, Nor Yungas, constituting a suitable area for the cultivation of tomato, but the attack of diseases caused by fungi, principally Phytophtora infestans, with an incidence of rate of 98%, which is increased by high temperature, humidity, precipitation and fog, all of which favor the spread of this fungus. For this reason farmers are forced to use chemical products that cause problems of resistance of the causal agent of the illnesses. The FAO (1992) estimates 3 million poisonings annually at a global level of farmers and families as a result of chemicals, which cause in turn a residual effect, environmental pollution and creates and additional cost in production. In the investigation of intoxication by agrochemicals in Bolivia, in a population of 870 persons studied mentioned that, 88% are unaware of the risks associated with the use and management of using them; the cases of poisonings are more frequent in tropical plains with 46%, the valleys with 26%, the inter-Andean valleys with 14% and the high plains with 12%, without mentioning those of suicide origin. For this reason, the object of the present investigation is to try to control the late blight disease (Phytophtora infestans) in the cultivation of the tomato (Lycopersicum sculentum), with biocides, to eliminate or diminish the use of agrochemical products.