Resumo

SANTILLANO-CAZARES, Jesús; LOPEZ-LOPEZ, Ángel; ORTIZ-MONASTERIO, Iván  e  RAUN, W. R.. Use of optical sensor technology for the fertilization of wheat (Triticum aestivum L.). Terra Latinoam [online]. 2013, vol.31, n.2, pp.95-103. ISSN 2395-8030.

Despite its economic importance, wheat production in the valley of Mexicali, B.C., Mexico, is going through difficult times due to its low profitability. One of the causes of the low profitability of wheat production may reside in farmers' using more nitrogen (N) fertilizers than needed. Moreover, the N that is not recovered by the crop is lost to the environment, accentuating pollution issues. One innovative strategy, optical sensor based technology (GreenSeekerTM) along with a mathematical algorithm and a nitrogen rich strip, is showing efficacy for sustainable fertilizer management worldwide. The objectives of this work were two; first, to generate a reliable yield prediction equation for locally grown wheat and second, to compare wheat yields, fertilizer rates and chemical fertilizer costs, using the sensor based technology versus the farmer's conventional fertilization practice. Calibration, validation and technology transfer trials were established from 2010 to 2012. A yield prediction equation was obtained that proved to be useful in recommending optimal fertilizer rates. Without a yield reduction (P = 0.2713), the sensor based technology fertilization mean rate was 68 kg N ha-1 lower than that applied by farmers following their conventional practice (P = 0.0015). These savings (in Mexican currency) accounted for $ 1339 ha-1. It is concluded that in Mexicali, through the use of sensor based technology, it is possible to obtain substantial savings on wheat related fertilizer costs, to contribute to increasing profitability for farmers and to reduce environmental impacts by avoiding unnecessary fertilizer application rates.

Palavras-chave : sustainable agriculture; GreenSeeker®; calibration; validation; technology transfer.