Papers by Дишко Валентина
Sensors, Jan 4, 2024
Fusarium graminearum and F. culmorum are considered some of the most dangerous pathogens of plant... more Fusarium graminearum and F. culmorum are considered some of the most dangerous pathogens of plant diseases. They are also considerably dangerous to humans as they contaminate stored grain, causing a reduction in yield and deterioration in grain quality by producing mycotoxins. Detecting Fusarium fungi is possible using various diagnostic methods. In the manuscript, qPCR tests were used to determine the level of wheat grain spoilage by estimating the amount of DNA present. High-performance liquid chromatography was performed to determine the concentration of DON and ZEA mycotoxins produced by the fungi. GC-MS analysis was used to identify volatile organic components produced by two studied species of Fusarium. A custom-made, low-cost, electronic nose was used for measurements of three categories of samples, and Random Forests machine learning models were trained for classification between healthy and infected samples. A detection performance with recall in the range of 88-94%, precision in the range of 90-96%, and accuracy in the range of 85-93% was achieved for various models. Two methods of data collection during electronic nose measurements were tested and compared: sensor response to immersion in the odor and response to sensor temperature modulation. An improvement in the detection performance was achieved when the temperature modulation profile with short rectangular steps of heater voltage change was applied.
Sensors, Sep 14, 2023
Fusarium is a genus of fungi found throughout the world. It includes many pathogenic species that... more Fusarium is a genus of fungi found throughout the world. It includes many pathogenic species that produce toxins of agricultural importance. These fungi are also found in buildings and the toxins they spread can be harmful to humans. Distinguishing Fusarium species can be important for selecting effective preventive measures against their spread. A low-cost electronic nose applying six commercially available TGS-series gas sensors from Figaro Inc. was used in our research. Different modes of operation of the electronic nose were applied and compared, namely, gas adsorption and desorption, as well as modulation of the sensor's heating voltage. Classification models using the random forest technique were applied to differentiate between measured sample categories of four species: F. avenaceum, F. culmorum, F. greaminarum, and F. oxysporum. In our research, it was found that the mode of operation with modulation of the heating voltage had the advantage of collecting data from which features can be extracted, leading to the training of machine learning classification models with better performance compared to cases where the sensor's response to the change in composition of the measured gas was exploited. The optimization of the data collection time was investigated and led to the conclusion that the response of the sensor at the beginning of the heating voltage modulation provides the most useful information. For sensor operation in the mode of gas desorption/absorption (i.e., modulation of the gas composition), the optimal time of data collection was found to be longer.
Plants, Feb 11, 2024
In the latest literature, climate models show that the conditions for pines, spruces, larches, an... more In the latest literature, climate models show that the conditions for pines, spruces, larches, and birches will deteriorate significantly. In Poland, as well as in other European countries, there are already signs of the decline of these species. This review article deals with the symbiotic relationships between fungi and plants, which can hardly be overestimated, using the example of pine trees. These are the oldest known symbiotic relationships, which are of great benefit to both components and can help plants, in particular, survive periods of severe drought and the attack of pathogens on the roots. This article describes symbioses and their causal conditions, as well as the mycorrhizal components of pine trees and their properties; characterizes ectomycorrhizal fungi and their mushroom-forming properties; and provides examples of the cultivation of pure fungal cultures, with particular attention to the specificity of the mycorrhizal structure and its effects on the growth and development of Pinus species. Finally, the role of mycorrhiza in plant protection and pathogen control is described.
Forests
Heterobasidion annosum (Fr.) Bref. sensu lato (s.l.) is a dangerous forest pathogen causing root ... more Heterobasidion annosum (Fr.) Bref. sensu lato (s.l.) is a dangerous forest pathogen causing root and butt rot disease in most conifers of the northern hemisphere. This pathogen is most widespread in the forests of Europe and North America. The economic impact on forestry related to tree mortality, reduction in timber yield, and wood rot is calculated in millions of dollars and euros. The genus Heterobasidion (Basidiomycota; Russulales) has been relatively recently separated into three genetically distinct groups (H. annosum, H. insulare and H. araucariae) comprising a total of 12 species and one newly described hybrid taxon. These species are the best studied in terms of the ecology, the physiology of control methods, and the tree’s resistance to the pathogen. The article gives an overview of the symptoms and the etiology of the disease and provides information on ways to recognize the disease and limit the economic damage.
Sensors
In the construction of electronic nose devices, two groups of measurement setups could be disting... more In the construction of electronic nose devices, two groups of measurement setups could be distinguished when we take into account the design of electronic nose chambers. The simpler one consists of placing the sensors directly in the environment of the measured gas, which has an important advantage, in that the composition of the gas is not changed as the gas is not diluted. However, that has an important drawback in that it is difficult to clean sensors between measurement cycles. The second, more advanced construction, contains a pneumatic system transporting the gas inside a specially designed sensor chamber. A new design of an electronic nose gas sensor chamber is proposed, which consists of a sensor chamber with a sliding chamber shutter, equipped with a simple pneumatic system for cleaning the air. The proposal combines the advantages of both approaches to the sensor chamber designs. The sensors can be effectively cleared by the flow of clean air, while the measurements are pe...
Forests
A 20-year study of a pine stand on post-agricultural land showed that woody debris in the form of... more A 20-year study of a pine stand on post-agricultural land showed that woody debris in the form of organic matter can be successfully used to restore symbiotic mycorrhizal communities, as is the case with forest soils. Woody substrates restored organic matter in soils altered by long agricultural use and had a positive effect on the composition of mycobiota antagonistic to pathogens, especially to Heterobasidion annosum, the causal agent of the dangerous disease root and stump rot of many forest tree species, including stands of Pinus sylvestris (L.). In a study that started in 2001 in the forest district of Czarne Człuchowskie (northern Poland), the following organic materials were used: wood residues (W), sawdust (S), bark compost (B), and compost applied to the root zone during planting (G). The organic materials were spread in the form of mulch over the entire area during planting. After twenty years, it was found that the substrates used provided suitable growth conditions for m...
Сучасний стан та перспективи використання селекційних об’єктів ДСДЛЦ «Веселі Боковеньки»
Лісове і садово-паркове господарство, Jan 3, 2018
Scientific Bulletin of UNFU, 2020
За умов глобальної зміни клімату зростає актуальність досліджень, спрямованих на підвищення проду... more За умов глобальної зміни клімату зростає актуальність досліджень, спрямованих на підвищення продуктивності і біологічної стійкості лісів. Особливо увагу привертають дослідження сосни звичайної (Pinus sylvestris L.), яка займає широкий ареал і характеризується складною внутрішньовидовою структурою. Одним із чинників абіотичного стресу для сосни звичайної є спалахи масового розмноження стовбурових комах-шкідників. Рослини, які періодично перебувають під впливом стресу, вимушені адаптуватися до нього шляхом фізіолого-біохімічної та анатомо-морфологічної перебудови. Отже, важливим аспектом формування стійких до стрес-чинників, зокрема до нападу комах, соснових деревостанів є біохімічна індикація стану дерев, для якої використовують продукти основного обміну та вторинні метаболіти. У Київському Поліссі в осередку "короїдного" усихання досліджено морфологічні параметри хвої, а також вміст водорозчинних білків і низькомолекулярних сполук фенольної природи (флавонолів – у хвої; ка...
Forestry and Forest Melioration
Висвітлено результати морфологічних і цитологічних досліджень насінного матеріалу дерев сосни зви... more Висвітлено результати морфологічних і цитологічних досліджень насінного матеріалу дерев сосни звичайної різного санітарного стану в осередках всихання насаджень, уражених кореневою губкою («умовно стійких», «хворих», контрольних) у ДП «Харківська ЛНДС». Визначено масу насіння та його схожість, мітотичну активність клітин апікальних меристем корінців і кількість сім’ядолей проростків. Насіння «умовно стійких» дерев, як порівняти з насінням «хворих», характеризується більшою середньою масою (на 18,5 %) і не поступається енергією проростання (65 і 64 % відповідно). Підтверджено стабільність рівня мітотичної активності клітин та її більшу інтенсивність у корінцях проростків із насіння «умовно стійких» дерев, порівнюючи з «хворими». Для «умовно стійких» дерев зафіксовано більшу, ніж в інших варіантах, сумарну частку проростків із шістьма і більше сім’ядолями. Отримані результати свідчать про можливість використання застосованих методів для ранньої діагностики молодих дерев сосни звичайно...
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Papers by Дишко Валентина