IDENTIFICATION OF WEEDS IN CASSAVA CROP IN THE PROVINCES OF HERRERA AND VERAGUAS

Abstract

Weeds are strongly competitive plants in cassava crops, but they are important components of agroecosystems, so it is important to identify their species to study their ecological aspects. The aim of this research was to recognize weeds associated with the cassava crop and to know aspects of their abundance and richness, which are fundamental factors for the analysis of agroeconomic thresholds, and as the first strategy for integrated management of agroecosystems. Agroecological scope: lands belonging to the dry tropical forest of the Pacific coast of the Isthmus, with an isotropic to isothermal temperature regime. The collection and georeferencing of the weeds were carried out in the districts of Atalaya (Veraguas), Las Minas, Pesé and Ocú (Herrera) between 94 and 183 masl, during the years 2016 and 2017, in the dry season (January to March) and rainy season (October to December). The biological diversity and equity of the species was carried out using the Shannon-Weaver and Simpson indices. In each plot a zigzag trek was carried out and samples of invading weeds were collected, 99 species belonging to 30 botanical families were identified. We identified 79 species of dicotyledonous weeds, representing 80%, grouped into 27 families: Acanthaceae, Apocynaceae, Amaranthaceae, Asclepiadaceae, Asteraceae, Bignoniaceae, Boraginaceae, Convolvulaceae, Cucurbitaceae, Euphorbiaceae, Fabaceae, Loganiaceae, Malvaceae, Melastomataceae, Menthaceae, Onagraceae, Piperaceae, Plantaginaceae, Portulacaceae, Rubiaceae, Solanaceae, Scrophulariaceae, Sterculiaceae, Tiliaceae, Verbenaceae, Violaceae, Zygophyllaceae. The remaining 20 species belonging to the monocotyledons represented 20%, grouped into three families: Commelinaceae, Cyperaceae and Poaceae. It resulted in a high biodiversity of 4.5 with the Shannon-Weaver Indices and a high similarity of 0.98 with Simpson. The richness characterized in the study area was 30 families with 84 genera and 99 species.