Vasileios Liakos

Dr. Vasileios Liakos

orcid

Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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16 July 2025 in Agronomy
Verified
Journal Article
Open access
PDF file
ATAlexandros Tsitouras
Alexandros Tsitouras
Christos NoulasChristos Noulas
Christos Noulas
VLVasileios Liakos
Vasileios Liakos
SSStamatis Stamatiadis
Stamatis Stamatiadis
MTMiltiadis Tziouvalekas
Miltiadis Tziouvalekas
Eleftherios EvangelouEleftherios Evangelou
Eleftherios Evangelou
Variable-rate nitrogen (VR-N) application allows farmers to optimize nitrogen (N) input site-specifically within field boundaries, enhancing both economic efficiency and environmental sustainability. In this study, VR-N technology was applied to durum wheat in two small-scale commercial fields (3–4 ha each) located in distinct agro-climatic zones of Thessaly, central Greece. A real-time VR-N application algorithm was used to calculate N rates based on easily obtainable near-real-time data from unmanned aerial vehicle (UAV) imagery, tailored to the crop’s actual needs. VR-N implementation was carried out using conventional fertilizer spreaders equipped to read prescription maps. Results showed that VR-N reduced N input by up to 49.6% compared to the conventional uniform-rate N (UR-N) application, with no significant impact on wheat yield or grain quality. In one of the fields, the improved gain of VR-N when compared to UR-N was 7.2%, corresponding to an economic gain of EUR 163.8 ha−1, while in the second field—where growing conditions were less favorable—no considerable VR-N economic gain was observed. Environmental benefits were also notable. The carbon footprint (CF) of the wheat crop was reduced by 6.4% to 22.0%, and residual soil nitrate (NO3−) levels at harvest were 13.6% to 36.1% lower in VR-N zones compared to UR-N zones. These findings suggest a decreased risk of NO3− leaching and ground water contamination. Overall, the study supports the viability of VR-N as a practical and scalable approach to improve N use efficiency (NUE) and reduce the environmental impact of wheat cultivation which could be readily adopted by farmers.

17 June 2025 in Preprints.org
Verified
Preprint
Open access
PDF file
ATAlexandros Tsitouras
Alexandros Tsitouras
Christos NoulasChristos Noulas
Christos Noulas
VLVasileios Liakos
Vasileios Liakos
SSStamatis Stamatiadis
Stamatis Stamatiadis
MTMiltiadis Tziouvalekas
Miltiadis Tziouvalekas
Eleftherios EvangelouEleftherios Evangelou
Eleftherios Evangelou
Variable-rate nitrogen (VR-N) application allows farmers to optimize nitrogen (N) input site-specifically within field boundaries, enhancing both economic efficiency and environmental sustainability. In this study, VR-N technology was applied to durum wheat in two small-scale commercial fields (3–4 ha each) located in distinct agro-climatic zones of Thessaly, central Greece. A real-time VR-N application algorithm was used to calculate N rates based on easily obtainable near real-time data from unmanned aerial vehicle (UAV) imagery, tailored to the crop’s actual needs. VR-N implementation was carried out using conventional fertilizer spreaders equipped to read prescription maps. Results showed that VR-N reduced N input by up to 50% compared to the conventional uniform rate N (UR-N) application, with no significant impact on wheat yield or grain quality. In one of the fields, VR-N led to a yield increase of 7.2%, corresponding to an economic gain of €164 ha⁻¹, while in the second field—where growing conditions were less favorable—no significant yield advantage was observed. Environmental benefits were also notable. The carbon footprint (CF) of the wheat crop was reduced by 6. 4% to 22.0%, and residual soil nitrate (NO3¯) levels at harvest were 13% to 36% lower in VR-N zones compared to UR-N zones. These findings suggest a decreased risk of NO3¯ leaching and ground water contamination. Overall, the study supports the viability of VR-N as a practical and scalable approach to improve N use efficiency (NUE) and reduce the environmental impact of wheat cultivation which could be readily adopted by farmers.

12 June 2023 in Plants
Verified
Journal Article
Open access
PDF file
VLVasileios Liakos
Vasileios Liakos
INIoannis Navrozidis
Ioannis Navrozidis
Eleni I. KoutsogeorgiouEleni I. Koutsogeorgiou
Eleni I. Koutsogeorgiou
Nikoloz GogolashviliNikoloz Gogolashvili
Nikoloz Gogolashvili
ESEvgenia Samourgkanidou
Evgenia Samourgkanidou
Stefanos AndreadisStefanos Andreadis
Stefanos Andreadis
The brown marmorated stink bug, Halyomorpha halys Stål (Hemiptera: Pentatomidae), is native to Japan, China, Taiwan, and Korea. Its dispersion from Asia to the United States of America and Europe caused serious damage to fruit, vegetables, and high-value crops. In Greece, damages are reported in kiwi orchards in the regions of Pieria and Imathia, which are the main production areas of kiwifruit. Greek kiwifruit production is expected to increase twofold within the next years. The aim of this research is to study the terrain and canopy properties that may have an impact on the development of H. halys populations. Thus, five kiwi orchards in total were selected in the regions of Pieria and Imathia. Τen traps were installed from early June to late October within each selected kiwi orchard–two types of traps at every side of the orchards and the center. The installed traps were examined weekly and the number of the captured H. halys was recorded. During the same days, sentinel satellite images were analyzed to calculate the vegetation index, NDVI (Normalised Difference Vegetation Index), and NDWI (Normalised Difference Water Index). The results showed population variability within the kiwi orchards since the population of H. halys was higher in areas with high NDVI and NDWI values. Additionally, our research revealed that H. halys prefers to develop populations at higher altitudes at both regional and field scales. The results of this research can be used to reduce damages by H. halys in kiwi orchards using different rates of pesticides depending on the prediction of the population size. There are multiple benefits of the proposed practice, such as a reduction in the production cost of kiwifruits, an increase in farmers’ profit, and environmental protection.

9 October 2026 in Preprints.org
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IRIOANNIS RAPTIS
IOANNIS RAPTIS
VLVasileios Liakos
Vasileios Liakos
AMAthanasios Makris
Athanasios Makris
ZTZisis Tsiropoulos
Zisis Tsiropoulos
IGIOANNIS GRAVALOS
IOANNIS GRAVALOS
Smart agricultural technologies can improve input efficiency and environmental performance, but their benefits depend on farmers’ knowledge and use. This study assessed knowledge and use of new agricultural technologies among Greek crop farmers, perceptions of sustainable agriculture and environmental impacts, and the usefulness of agricultural education. A cross-sectional survey was conducted from September 2023 to May 2024 among 1,054 crop farmers across all 13 Greek regions using convenience sampling. Pearson’s chi-square tests and Cramer’s V examined associations between technology knowledge and age, education, and agricultural experience. Overall, 56.8% reported knowledge of new technologies, 29.7% reported technologically equipped machinery, and 17.9% reported using such technologies. Knowledge was significantly associated with age (χ²(4) = 64.41, V = 0.249), education (χ²(5) = 204.02, V = 0.444), and experience (χ²(9) = 182.51, V = 0.420; all p < 0.001). Furthermore, 70.1% reported no knowledge of sustainable agriculture, while the perceived usefulness of agricultural education was very high (mean = 4.73/5). The findings indicate a gap between reported technological knowledge and actual use and support practical training in smart machinery, digital skills, environmental protection, and agronomic practices. Given the cross-sectional design, convenience sampling, and self-reported measures, the observed associations should not be interpreted causally.

22 March 2025 in Insects
Verified
Journal Article
Open access
PDF file
VLVasileios Liakos
Vasileios Liakos
Eleni I. KoutsogeorgiouEleni I. Koutsogeorgiou
Eleni I. Koutsogeorgiou
SHSOFIA HAROULI
SOFIA HAROULI
INIoannis Navrozidis
Ioannis Navrozidis
GPGeorgios Proias
Georgios Proias
Stefanos AndreadisStefanos Andreadis
Stefanos Andreadis
Precision Agriculture is an agricultural management strategy that aims to increase farmers’ profit, maximize crop productivity and sustainability, and protect the environment by applying inputs in optimum rates based on plant needs. The delineation of site-specific management zones is a crucial step at the application of Precision Agriculture. However, the procedure of delineating management zones for pest management is difficult since pest populations are dynamic and change spatially and temporally throughout a growing season. The objectives of this work is to study kiwi canopy characteristics, to correlate them with Halyomorpha halys (Hemiptera: Pentatomidae) populations and delineate management zones for pesticide applications in variable rates. To achieve this, four kiwi orchards in total were selected in the regions of Pieria and Imathia in Greece. Τen traps were installed from early May to late October within each selected kiwi orchard: two types of traps at every side of the orchards and the center. The installed traps were examined weekly, and the number of the captured H. halys was recorded. During the same days, sentinel satellite images were analyzed to calculate the indices: NDVI (Normalized Difference Vegetation Index) and NDWI (Normalized Difference Water Index). The collected data were combined in a GIS software to delineate management zones using a K means algorithm and unsupervised classification. The results of this three-year study showed population variability within the kiwi orchards since the population of H. halys was higher in field regions where NDVI and NDWI values were high. The delineation of management zones revealed that there are spatio-temporal stable zones in each field where there is high, medium, and low risk to develop H. halys populations. The benefits of the proposed strategy are multiple since it is expected that farmers will be able to reduce the production expenses of kiwifruits and environmental protection while increasing profit.