BREDEMEIER, Christian; VARIANI, Clever; ALMEIDA, Danielle and ROSA, Alexandre Tonon. Estimativa do potencial produtivo em trigo utilizando sensor óptico ativo para adubação nitrogenada em taxa variável. Cienc. Rural [online]. 2013, vol.43, n.7, pp. 1147-1154. Epub June 18, 2013. ISSN 0103-8478. http://dx.doi.org/10.1590/S0103-84782013005000080.
Research tests the relations between normalized difference vegetation index (NDVI) and grain yield of four wheat cultivars
Researchers from Universidade Federal do Rio Grande do Sul (UFRGS), of Brazil, demonstrated that normalized difference vegetation index (NDVI) measured by an active sensor was effective for identifying variations in productivity in wheat culture. The study was published in Ciência Rural journal, v.43, n.7, of July 2013.
The study aimed to evaluate the relation between NDVI, measured by active optical sensor, and grain yield in four wheat cultivars, aiming to develop more precise procedures for nitrogen topdressing dose varied. Therefore, researchers conducted a field experiment in 2009, which evaluated the NDVI in different stages of development and grain yield. NDVI readings were effective in identifying variations in wheat yield.
In practice, the study demonstrates that it is possible to adopt a single model to describe the relationship between NDVI and yield wheat potential for the four cultivars tested in the experiment. The quantification of NDVI values can assist in achieving the nitrogen application in variable dose according to estimated crop yield potential of each site within the crop.
For the researcher Christian Bredemeier, the importance of the research is precisely to assist in the application of nitrogen. "In most situations, the application of nitrogen fertilizers is carried out without considering the spatial variability of soil and crop. The variables measuring during the development of culture, such as NDVI, is an opportunity to improve the yield and quality of grain by localized application of nitrogen fertilizers," he evaluates.
The study is positioned in a promising area of research studied in Brazil. Currently, there are few research groups in the country studying the application of optical sensors as a tool for the realization of the nitrogen dose varied. Some groups also work with different sensors and with varied crops, especially corn, wheat and sugar cane.