search
for
 About Bioline  All Journals  Testimonials  Membership  News  Donations


Chilean Journal of Agricultural Research
Instituto de Investigaciones Agropecuarias, INIA
ISSN: 0718-5820
EISSN: 0718-5839
Vol. 74, No. 2, 2014, pp. 204-245
Bioline Code: cj14031
Full paper language: English
Document type: Note
Document available free of charge

Chilean Journal of Agricultural Research, Vol. 74, No. 2, 2014, pp. 204-245

 en Effect of different day and night nutrient solution concentrations on growth, photosynthesis, and leaf NO3- content of aeroponically grown lettuce
Albornoz, Francisco; Lieth, J. Heinrich & Gonzalez-Fuentes, José A.

Abstract

Nitrate content in leafy green vegetables has raised concerns among consumers and policy makers worldwide. Several cultural practices have been evaluated to manipulate NO3- content in fresh leaves with varying degrees of success. The present study was conducted to evaluate different concentrations of the nutrient solution applied during the day (D) and night (N) to aeroponically grown lettuce ( Lactuca sativa check for this species in other resources L.) in Davis, California, USA, in the spring of 2012 with the objective of assessing the effect on growth, leaf photosynthesis, and nitrate accumulation in leaves. Two different treatments in the nighttime solution concentration (D25/N75, EC: 1.8 dS m-1; and D25/N50, EC: 1.2 dS m-1),a day nutrient solution of EC 0.6 dS m-1, plus a day and night treatment with constant EC (D50/N50, EC: 1.2 dS m-1) were applied. Plant growth, leaf photosynthesis, and leaf nutrient content were evaluated after 3 wk of growth. Mean shoot weight was 106.3 g with no differences among treatments. Root biomass was lower with D25/N75 (0.14 vs. 0.85 g in the other treatments). The maximum rate of leaf photosynthesis was 66% lower with D25/N75 than in the other treatments. Nitrogen, P, K, Ca, and Mg were lower in leaf tissue in the treatments with different solution concentrations where leaf NO3- content was reduced by approximately 75%. Switching nutrient solution concentration between day and night is a viable practice to reduce NO3- in lettuce leaves with no detriment to leaf production.

Keywords
Aeroponics; Lactuca sativa; leaf nitrate concentration; lettuce photosynthesis

 
© Copyright 2014 - Chilean Journal of Agricultural Research
Alternative site location: http://www.inia.cl

Home Faq Resources Email Bioline
© Bioline International, 1989 - 2017, Site last up-dated on 05-Dec-2017.
Site created and maintained by the Reference Center on Environmental Information, CRIA, Brazil
System hosted by the Internet Data Center of Rede Nacional de Ensino e Pesquisa, RNP, Brazil