Next Article in Journal
Lettuce Biomass Accumulation and Phytonutrient Concentrations Are Influenced by Genotype, N Application Rate and Location
Next Article in Special Issue
Growth, Water-Use Efficiency, Stomatal Conductance, and Nitrogen Uptake of Two Lettuce Cultivars Grown under Different Percentages of Blue and Red Light
Previous Article in Journal / Special Issue
New Media Components and Fertilization to Accelerate the Growth of Citrus Rootstocks Grown in a Greenhouse
Open AccessFeature PaperArticle

Effects of Elevated Temperature and Potassium on Biomass and Quality of Dark Red ‘Lollo Rosso’ Lettuce

1
Department of Plant and Soil Sciences, Mississippi State University, North Mississippi Research and Extension Center, Verona, MS 38879, USA
2
Department of Plant Sciences, The University of Tennessee, Knoxville, TN 37996, USA
*
Author to whom correspondence should be addressed.
Horticulturae 2018, 4(2), 11; https://doi.org/10.3390/horticulturae4020011
Received: 2 May 2018 / Revised: 12 June 2018 / Accepted: 14 June 2018 / Published: 16 June 2018
(This article belongs to the Special Issue Plant Production in Controlled Environment)
Lettuce is an economically important crop for small and medium-sized growers. When grown in adverse environmental conditions, lettuce is vulnerable to a deterioration of yield and quality. Research concerning the impact of elevated potassium (K) levels on leafy vegetables, such as lettuce, is lacking. Therefore, seeds of dark-red ‘Lollo’ lettuce were germinated under greenhouse conditions at 25/20 °C (day/night). Plants were transferred into 11-L containers and placed into growth chambers at 25 and 33 °C. Plants were grown with K treatments of 117.3 (control), 234.6 (2×), 469.2 (4×), and 4) 938.4 (8×) mg·L−1. Increasing K treatments resulted in a negative quadratic response on lettuce dry mass and generated 14% more leaf calcium at 234.6 mg·L−1. An increase in temperature from 25 to 33 °C increased leaf dry matter and biomass by 40% and 43%, respectively. Leaf water content increased by 3% as temperature increased. Plants grown at 33 °C had greater quercetin glycosides compared to plants grown at 25 °C. The results from this study suggest that temperature is a stronger regulatory factor than increasing K in the determination of lettuce yield and quality. Increasing K concentration to 234.6 mg·L−1 results in greater concentrations of leaf minerals without compromising plant yield. View Full-Text
Keywords: red lettuce; hydroponics; flavonoids; heat stress; growth chambers; phenolic acids; mineral nutrients red lettuce; hydroponics; flavonoids; heat stress; growth chambers; phenolic acids; mineral nutrients
Show Figures

Figure 1

MDPI and ACS Style

Sublett, W.L.; Barickman, T.C.; Sams, C.E. Effects of Elevated Temperature and Potassium on Biomass and Quality of Dark Red ‘Lollo Rosso’ Lettuce. Horticulturae 2018, 4, 11.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop