Author(s): SOUZA, D. P. de; SANCHES, A. C.; MAFFEI, R. G.; JESUS, F. L. F. de; MENDONÇA, F. C.; PEZZOPANE, J. R. M.

Summary: Capacitive probes are devices with high investment costs, but they have the advantage of mobility and practical use compared with lysimeters. Therefore, studies are needed to verify the use of this technique in the determination of water consumption by forage plants. The objective of this work was to evaluate the use of a capacitive probe to estimate the water consumption in two cropping systems compared to the data obtained by the weighing lysimeter. They were: single (Marandu palisadegrass) and consortium (Marandu palisadegrass+ black oats + ryegrass). The study was carried out in an experimental area of ESALQ/USP. Data from six cycles of Marandu palisadegrass development were used, four in exclusive cultivation and two in consortium cultivation. Soil moisture was evaluated by the Diviner® capacitive probe and used to calculate the soil water balance. The coefficient of culture data (Kc) estimated by the capacitive probes were correlated with those determined in the weighing lysimeters, correlations were significant (p<0,05) and linear equations. The estimates made with the probe differed from those made with lysimeters overestimating 78% of the studied cases, Kc values of the probes in relation to lysimeters.

Publication year: 2017

Types of publication: Paper in annals and proceedings

Unit: Embrapa Southeastern Livestock

Keywords: Capacitive probe, Coefficient of culture, Crop evapotranspiration