Abstracto
- As a contribution to the reduction of the vulnerability of the productive system of onion ocañera (Allium cepa L.), against the agroclimatic risk, associated to restrictive conditions of humidity due to water deficit in the soil in the municipality of Ocaña, Norte de Santander, the project Risk Reduction and Adaptation to Climate Change, developed by the Colombian Agricultural Research Corporation, validated technological options to increase water productivity in onion cultivation and face adverse effects of climate variability. The identification and subsequent validation of these strategies was carried out participatively with producers and technical assistants, taking into account the historical dynamics of the climate, which can provide an overview of potential agroclimatic threats, and the biophysical characteristics of the municipality added to the probability of occurrence of extreme climatic events that affect the crop, which constitutes the susceptibility of the system to such a threat. In Ocaña, the efficient use of water resources and the organic fertilization of the crop were considered. The first was based on the establishment of a system of irrigation by micro-sprinkling, designed from local meteorological characteristics, water requirements of the onion and soil properties that determine the state of the water inside the profile. The fertilization of the onion production system was carried out by incorporating composted organic matter, poultry manure and vermicompost. The positive effects of these practices on the yield of the crop and on the efficient use of water were evidenced, since the irrigation by micro sprinkling decreased the consumption in 42.7%, at the same time it increased the productivity of the water in 112.4% and the yield in 10%, in comparison with the conventional management (irrigation with hose and raw chicken manure), which together translates into an increase in the adaptive capacity of the productive system in the face of water deficit conditions.
