Evaluación del estrés hídrico en el cultivo de brócoli (Brassica oleracea var. Itálica), mediante técnicas espectrales

Abstract

Multispectral sensors are very useful in the early detection of stress, the images generated by these teams together with the vegetation indices allow estimating the quantity, quality and development of the vegetation. The present investigation carried out the evaluation of a methodology based on spectral analysis of images for the estimation of the hydric state in broccoli plants (Brassica oleracea var. Itálica). Work was done on an experimentation" plot at the Faculty of Agricultural Sciences of the University of Cuenca. Five treatments were evaluated; T1-Waterlogging, T2, T2 and T3 at 25-50-75% respectively in reference to Field Capacity and T5-Witness, in broccoli culture. He underwent instantaneous water stress at different irrigation doses; T1> 0.52 L / p, T2 0.13 L / p, T3 0.26 L / p, T4 0.39 L / p and Witness with 0.52 L / p for thirteen days, in two periods; 45 and 75 days after the transplant. The images were taken with the Parrot Sequoia sensor, and physiological variables such as; stomatal conductance and relative water content to validate the spectral results of the normalized difference vegetation index for the two periods. The results showed significant differences P = 0.0022 for the vegetation index in the spectral analysis between treatments in the two periods studied. Pearson's correlations made between vegetation index and physiological variables determined an R coefficient> 0.7 for the first period. This research suggests that the spectral techniques applied to images captured with the Parrot Sequoia sensor, allow analyzing the water state in the broccoli culture.