Next Article in Journal
Next Article in Special Issue
Previous Article in Journal
Previous Article in Special Issue
Sensors 2014, 14(7), 11492-11503; doi:10.3390/s140711492
Article

An Analysis of Electrical Impedance Measurements Applied for Plant N Status Estimation in Lettuce (Lactuca sativa)

1,* , 1
, 1
, 1
, 1
, 1
, 2
 and 1,*
Received: 16 May 2014; in revised form: 19 June 2014 / Accepted: 19 June 2014 / Published: 27 June 2014
(This article belongs to the Special Issue Agriculture and Forestry: Sensors, Technologies and Procedures)
View Full-Text   |   Download PDF [370 KB, uploaded 27 June 2014]
Abstract: Nitrogen plays a key role in crop yields. Hence, farmers may apply excessive N fertilizers to crop fields, inducing environmental pollution. Crop N monitoring methods have been developed to improve N fertilizer management, most of them based on leaf or canopy optical-property measurements. However, sensitivity to environmental interference remains an important drawback. Electrical impedance has been applied to determine the physiological and nutritional status of plant tissue, but no studies related to plant-N contents are reported. The objective of this article is to analyze how the electrical impedance response of plants is affected by their N status. Four sets of lettuce (Lactuca sativa L.) with a different N-source concentrations per set were used. Total nitrogen and electrical impedance spectra (in a 1 to 100 kHz frequency range) were measured five times per set, three times every other day. Minimum phase angles of impedance spectra were detected and analyzed, together with the frequency value in which they occurred, and their magnitude at that frequency. High and positive correlation was observed between plant N content and frequency values at minimum phase angle with no significant variations detected between days of measurement. These results suggest that electrical impedance can be sensitive to plant N status.
Keywords: electrical impedance; characteristic frequency; plant N status; Lactuca sativa; plant nutrition electrical impedance; characteristic frequency; plant N status; Lactuca sativa; plant nutrition
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Export to BibTeX |
EndNote


MDPI and ACS Style

Muñoz-Huerta, R.F.; Ortiz-Melendez, A.J.; Guevara-Gonzalez, R.G.; Torres-Pacheco, I.; Herrera-Ruiz, G.; Contreras-Medina, L.M.; Prado-Olivarez, J.; Ocampo-Velazquez, R.V. An Analysis of Electrical Impedance Measurements Applied for Plant N Status Estimation in Lettuce (Lactuca sativa). Sensors 2014, 14, 11492-11503.

AMA Style

Muñoz-Huerta RF, Ortiz-Melendez AJ, Guevara-Gonzalez RG, Torres-Pacheco I, Herrera-Ruiz G, Contreras-Medina LM, Prado-Olivarez J, Ocampo-Velazquez RV. An Analysis of Electrical Impedance Measurements Applied for Plant N Status Estimation in Lettuce (Lactuca sativa). Sensors. 2014; 14(7):11492-11503.

Chicago/Turabian Style

Muñoz-Huerta, Rafael F.; Ortiz-Melendez, Antonio J.; Guevara-Gonzalez, Ramon G.; Torres-Pacheco, Irineo; Herrera-Ruiz, Gilberto; Contreras-Medina, Luis M.; Prado-Olivarez, Juan; Ocampo-Velazquez, Rosalia V. 2014. "An Analysis of Electrical Impedance Measurements Applied for Plant N Status Estimation in Lettuce (Lactuca sativa)." Sensors 14, no. 7: 11492-11503.


Sensors EISSN 1424-8220 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert