N-Source Determines Barley Productivity, Nutrient Accumulation, and Grain Quality in Cyprus Rainfed Agricultural Systems

Michalis Omirou; Dionysia Fasoula; Marinos Stylianou; Antonis A Zorpas; Ioannis M Ioannides

doi:10.3390/ijerph20053943

N-Source Determines Barley Productivity, Nutrient Accumulation, and Grain Quality in Cyprus Rainfed Agricultural Systems

Int J Environ Res Public Health. 2023 Feb 23;20(5):3943. doi: 10.3390/ijerph20053943.

Authors

Michalis Omirou¹, Dionysia Fasoula², Marinos Stylianou³, Antonis A Zorpas³, Ioannis M Ioannides¹

Affiliations

¹ Department of Agrobiotechnology, Agricultural Research Institute, P.O. Box 22016, Nicosia 1516, Cyprus.
² Department of Plant Breeding, Agricultural Research Institute, P.O. Box 22016, Nicosia 1516, Cyprus.
³ Laboratory of Chemical Engineering and Engineering Sustainability, Faculty of Pure and Applied Sciences, Open University of Cyprus, Giannou Kranidioti 89, Latsia, Nicosia 2231, Cyprus.

Abstract

The Eastern Mediterranean and Middle East (EMME) region is already experiencing the negative effects of increased temperatures and the increase in prolonged drought periods. The use of organic fertilization could be a valuable tool to meet the main challenges of climate change and maintain the productivity, quality, and sustainability of rainfed agricultural ecosystems. In the current study, we compare the effect of manure, compost, and chemical fertilization (NH₄NO₃) on barley grain and straw yield in a field study for three consecutive growing seasons. The hypothesis that the barley productivity, nutrient accumulation, and grain quality remain similar among the different nutrient management strategies was tested. The results showed that both growing season and type of nutrient source significantly affected barley grain and straw yield (F_6,96 = 13.57, p < 0.01). The lowest productivity was noticed in the non-fertilized plots while chemical and organic fertilization exhibited similar grain yield, ranging from 2 to 3.4 t/ha throughout the growing seasons. For straw, the use of compost had no effect on the yield in any of the growing seasons examined. The use of manure and compost had a significant effect on grain macro- and micronutrient content but this was highly related to growing season. Principal component analysis (PCA) clearly demonstrated the discrimination of the different type of fertilization on barley performance during the course of the study, while the application of compost was highly associated with an increase in micronutrients in grain samples. Furthermore, structural equational modeling (SEM) showed that both chemical and organic fertilization had a direct positive effect on macro- (r = 0.44, p < 0.01) and micronutrient (r = 0.88, p < 0.01) content of barley grain and a positive indirect effect on barley productivity through N accumulation in grain (β = 0.15, p = 0.007). The current study showed that barley grain and straw yield was similar between manure and NH₄NO₃ treatments, while compost exhibited a residual positive effect causing an increase in grain yield during the growing season. The results highlight that N fertilization under rainfed conditions is beneficial to barley productivity through its indirect effects on N accumulation in grain and straw, while it improves grain quality through the increased accumulation of micronutrients.

Keywords: barley; compost; manure; organic fertilization; principal component analysis.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Cyprus
Ecosystem
Edible Grain / chemistry
Fertilizers / analysis
Hordeum*
Manure / analysis
Micronutrients / analysis
Soil* / chemistry

Substances

Soil
Manure
Micronutrients
Fertilizers

Grants and funding

This research was financially supported by European Union within the LIFE+ORGANIKO (LIFE 14/CCM/CY/000990) project.