CONICET | Buscador de Institutos y Recursos Humanos

United Nations, Educational, Scientific and Cultural Organization (UNESCO), International Atomic Energy Agency (IAEA), The Abdus Salam, International Centre for Theoretical Physics (ICTp)

Resumen:

Many years ago, in the Argentinean Pampas, could be seen large areas characterized by cattle eating grass. Nowadays, this has changed considerably. Cattle production has been shifted to other areas and in its place different crops have been planted under no-till systems. These production systems have some advantages over the traditional ones as the decrease the erosion effect produced by water and wind and the increase of soil organic matter. However, as a important disadvantage, large quantities of herbicides are needed. Remote sensing has been identified as a promising technique for identifying weeds in crops, and potentially offers a solution to herbicides application. In the Centro de Investigaciones Ópticas (CIOp) of Argentina, we have developed a low cost sensor that has Light emission Diode (led´s) as detector elements. This is due to the fact that leds can be used both as emissors, (its most know application) and as detectors. So, in this case leds are used as filters and photodiodes, that is to say, significantly reducing the cost of sensor manufacture. In this work, I present the results of reflectance measurements performed with a leds based sensor. The results indicated that the latter method is possible for use with passive sensors to weeds detection in no-till agronomic system. I show the results obtained in the determination of the Normalized Difference Vegetation Index (NDVI) corresponding to 2007 field experiments concerning weeds detection in Soybean (Glicine max L.) sttubles to refine sensor-based herbicides rate recommendations.