Yield, Quality and Physiological Traits of Red Beet Under Different Magnesium Nutrition and Light Intensity Levels

Sara D’Egidio,Michele Pisante,Giancarlo Pagnani,Angelica Galieni,Fabio Stagnari

doi:10.3390/agronomy9070379

Sara D’Egidio, Michele Pisante + Show 3 more

Open Access

https://doi.org/10.3390/agronomy9070379

Copy DOI

Journal: Agronomy	Publication Date: Jul 15, 2019
Citations: 6	License type: CC BY 4.0

Affiliation: University of Teramo, Cereal Research Centre

Abstract

The effects of light intensity and Magnesium (Mg) supply on quality traits, yield and macronutrient assimilation of red beet plants were studied in two greenhouse experiments (in 2017 and 2018). According to a split-plot design, we compared two photosynthetically active radiation (PAR) levels (100% PAR, Full Light, FL and 50% PAR, Light Reduction, LR) as the main factor and three Mg application rates (0, 30, and 60 kg Mg ha−1: MG_0, MG_30 and MG_60, respectively) as the secondary factor. Yield and dry matter accumulations were principally affected by Mg. In both growing seasons, storage root dry weight (DW) increased about 5-fold in MG_60 with respect to MG_0; the highest leaves DW was achieved with the “LR × MG_60” treatment. Nitrogen and Mg contents in leaves and storage roots increased as Mg availability increased; also, the highest chlorophyll content was obtained combining LR and a high Mg rate. Moreover, the reflectance-derivative Normalized Difference Vegetation Index (NDVI670) and Chlorophyll Index (CI) allowed for discriminating the Mg sub-optimal supply in red beet plants. Sucrose was found to be the most abundant sugar in both the leaves and storage organs and was affected by Mg supply. Total phenolic content and betalains in storage roots at harvest were affected by both PAR and Mg application rates. Our results highlight the potential of Mg nutrition in ensuring good yield and quality of red beet crops.

Highlights

The chemical composition of vegetables depends on a number of factors, including plant genotype and growing conditions; the manipulation of crop management could represent a way to sharply induce the modification of edible organs, obtaining an improved quality of the final products [1,2,3,4]
We studied the effects of Mg supply under different photosynthetically active radiation (PAR) availabilities
A clear trend showed an increase in storage root yield as the Mg supply increased, regardless of PAR availability (Table 1)

Summary

Introduction

The chemical composition of vegetables depends on a number of factors, including plant genotype and growing conditions; the manipulation of crop management could represent a way to sharply induce the modification of edible organs, obtaining an improved quality of the final products [1,2,3,4]. Fertilization plays a key role since the accumulation of plant metabolites is closely associated with the availability of mineral elements in the growing substrates [5,6]. Mg is an important macronutrient for plant nutrition [7]. It is the second most abundant cation in cells and is involved in a wide range of biological activities, operating as the activator or regulator of many key enzymes in plant physiological processes [8]. As a central element of the chlorophyll (Chl) structure, Mg is important in the harvest of solar energy; it plays a critical role in phloem loading and the transportation of photoassimilates into sink organs, such as fruits, roots and seeds [9]. Mg deficiency results in (i) suppressing plant growth [8], as it directly affects photosynthesis [10,11]; (ii)

Methods

Results

Discussion

Conclusion