Tomas Necas

Dr. Tomas Necas

Mendel University in Brno, Faculty of Horticulture, Department of Fruit Science
orcid

Research Focus & Metrics

Academic Career Length

22Years (2005-Present)

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

Representative Publications

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1 March 2020 in Plant Disease
Verified
Journal Article
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Ales EichmeierAles Eichmeier
Ales Eichmeier
JPJ. Pecenka
J. Pecenka
MSMilan Spetik
Milan Spetik
Tomas NecasTomas Necas
Tomas Necas
IOI. Ondrasek
I. Ondrasek
David GramajeDavid Gramaje
David Gramaje
Juglans regia L. (English walnut) trees with cankers and dieback symptoms were observed in two regions in the Czech Republic. Isolations were made from diseased branches. In total, 138 fungal isolates representing 10 fungal species were obtained from wood samples and identified based on morphological characteristics and molecular methods: Cadophora novi-eboraci, Cadophora spadicis, Cryptovalsa ampelina, Diaporthe eres, Diplodia seriata, Dothiorella omnivora, Eutypa lata, Eutypella sp., Peroneutypa scoparia, and Phaeoacremonium sicilianum. Pathogenicity tests conducted under field conditions with all species using the mycelium-plug method indicated that Eutypa lata and Cadophora spp. were highly virulent to woody stems of walnut. This is the first study to detect and identify fungal trunk pathogens associated with diseased walnut trees in Europe.

23 April 2021 in Sustainability
Verified
Journal Article
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EZEliška Zezulová
Eliška Zezulová
MGMartina Göttingerová
Martina Göttingerová
PGPavel Gála
Pavel Gála
TKTomas Kiss
Tomas Kiss
Sezai ErcisliSezai Ercisli
Sezai Ercisli
Tomas NecasTomas Necas
Tomas Necas
Apricot fruits are a favorite for consumption; however, their kernels are a rich source of nutritionally interesting substances, too. Nevertheless, in processing of apricots, the kernels remain often unused. In this study, 32 cultivars of different origin were analyzed for their protein content and content of secondary metabolites (phenolics and flavonoids). The weight and taste of kernels were assessed and these data were summarized for an evaluation of the attractiveness of the studied apricot kernels. Results showed that the protein content of kernels ranged from 14.56% to 28.77% and did not depend on the origin or weight of kernel, or taste. In addition, total phenolic (63.5–1277.3 mg GAE/100 g DW) and total flavonoid (0–153.1 mg CE/100 g DW) contents and antioxidant capacity (483.4–2348.4 mg TE/100 g DW) were measured in kernels. In conclusion, the Czech hybrids LE-5959, LE-5500 and French cultivar Koolgat are prospective for kernel processing and consumption because of their high protein content and sweet taste. Hybrid LI-3-6, originating in China, showed high protein content as well but because of bitter taste could be useful rather in medicine.

17 June 2021 in Sustainability
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Journal Article
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Murat GuneyMurat Guney
Murat Guney
SKSalih Kafkas
Salih Kafkas
HKHakan Keles
Hakan Keles
MGMujgan Guney
Mujgan Guney
MGMuhammet Ali Gündeşli
Muhammet Ali Gündeşli
Geza BujdosóGeza Bujdosó
Geza Bujdosó
The food needs for increasing population, climatic changes, urbanization and industrialization, along with the destruction of forests, are the main challenges of modern life. Therefore, it is very important to evaluate plant genetic resources in order to cope with these problems. Therefore, in this study, a set of ninety-one walnut (Juglans regia L.) accessions from Central Anatolia region, composed of seventy-four accessions and eight commercial cultivars from Turkey, and nine international reference cultivars, was analyzed using 45 SSR (Simple Sequence Repeats) markers to reveal the genetic diversity. SSR analysis identified 390 alleles for 91 accessions. The number of alleles per locus ranged from 3 to 19 alleles with a mean value of 9 alleles per locus. Genetic dissimilarity coefficients ranged from 0.03 to 0.68. The highest number of alleles was obtained from CUJRA212 locus (Na = 19). The values of polymorphism information content (PIC) ranged from 0.42 (JRHR222528) to 0.86 (CUJRA212) with a mean PIC value of 0.68. Genetic distances were estimated according to the UPGMA (Unweighted Pair Group Method with Arithmetic Average), Principal Coordinates (PCoA), and the Structure-based clustering. The UPGMA and Structure clustering of the accessions depicted five major clusters supporting the PCoA results. The dendrogram revealed the similarities and dissimilarities among the accessions by identifying five major clusters. Based on this study, SSR analyses indicate that Yozgat province has an important genetic diversity pool and rich genetic variance of walnuts.

1 November 2021 in HortScience
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Journal Article
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MGMartina Göttingerová
Martina Göttingerová
MKMichal Kumšta
Michal Kumšta
EREliška Rampáčková
Eliška Rampáčková
TKTomáš Kiss
Tomáš Kiss
Tomas NecasTomas Necas
Tomas Necas
The apricot is attractive for several reasons, with the most important being the harvest period and the significant amount of contained substances that positively affect human health. This report discusses the identification and quantification of phenolic substances in 15 selected apricots. The following 14 phenolic compounds were identified: 4aminobenzoic acid, chlorogenic acid, cinnamic acid, flavonols quercetin and quercitrin, isoquercetin (quercetin-3-β-D-glucoside), rutin, resveratrol, vanillin, phloridzin, phloretin, epicatechin, catechin, and transpiceid. Significant amounts of phytochemicals found in apricot fruits are chlorogenic acid [0.69–21.94 mg/100 g fresh weight (FW)], catechin (0.55–10.75 mg/100 g FW), epicatechin (0.04–13.52 mg/100 g FW), and rutin (1.49–20.44 mg/100 g FW). Rutin and chlorogenic acid were the dominant compounds found in the studied set of cultivars. Furthermore, other important analytical properties of fruits (total acids, vitamin C, total content of phenolic substances, flavonoids, antioxidant capacity, and carotenoids) were also determined.

16 October 2020 in Agronomy
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Halil Ibrahim SagbasHalil Ibrahim Sagbas
Halil Ibrahim Sagbas
GIGulce ILHAN
Gulce ILHAN
HZHafida Zitouni
Hafida Zitouni
MAMuhammad Akbar Anjum
Muhammad Akbar Anjum
HHHafida Hanine
Hafida Hanine
Sezai ErcisliSezai Ercisli
Sezai Ercisli
Wild edible fruits have been used centuries by local people mainly for nutrition purposes and they have attracted the attention of researchers in the last decade throughout the world. Among wild edible fruits, the strawberry tree (Arbutus unedo) is widely distributed mainly in Mediterranean countries. However, the lack of information about strawberry tree genetic resources in Mediterranean countries is a major cause of its low exploitation by breeders. For a practical use and exploitation of the strawberry tree native germplasm, phenological, morphological, and biochemical characterization of the plant is essential. In this study, some important phenological, morphological, and biochemical characteristics of sixteen local strawberry tree genotypes were determined. Significant variations (p < 0.05) were observed in most of the investigated phenological, morphological, and biochemical traits of the genotypes. The genotypes were harvested between 2–21 November. The fruit weight and the number of fruits per cluster of the genotypes varied from 3.89 to 6.86 g and 3.61 to 7.94, respectively. Vitamin C and total dietary fiber contents of genotypes were found quite variable, ranging from 58 to 93 mg/100 g and 7.04 to 12.36 g/100 g, respectively. The fruits of the strawberry tree include mainly fructose and glucose rather than sucrose. Local strawberry tree genotypes are found to be promising for further valorization through horticultural characteristics for breeding. Some genotypes had significantly higher fruit weight, vitamin C concentrations, total dietary fiber, and total phenolic concentration and may be good selections for producing health products.

20 December 2021 in Sustainability
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Journal Article
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MMMartina Mrázová
Martina Mrázová
EZEliška Zezulová
Eliška Zezulová
PŠPetr Šnurkovič
Petr Šnurkovič
IOIvo Ondrášek
Ivo Ondrášek
Tomas NecasTomas Necas
Tomas Necas
Sezai ErcisliSezai Ercisli
Sezai Ercisli
Peaches (Prunus persica L.) are a popular and sought-after dessert fruit. This is mainly due to their flavour, aroma, attractive appearance, and high content of substances that play an important role in human nutrition. The present study was carried out to determine some important analytical properties (sugars/sucrose, glucose, fructose and sorbitol), total acid, total phenolics, flavonoids, antioxidant capacity, carotenoids and anthocyanins of 34 selected peach varieties. The analyses are also complemented by colorimetric measurements of peach skin colour using CIELAB and other chromatic parameters. The results show, for example, that all peach varieties are good sources of phenolic compounds (9.43–577 mg gallic acid equivalent (GAE).100 g−1), flavonoids (1.12–95.1 mg catechin equivalent (CAE).100 g−1), and antioxidant capacity (136–462 mg Trolox equivalent (TE).100 g−1).