Agriculture and forestry

Oleksandr Gumeniuk – PhD student at the Department of Botany, Genetics and Plant Protection of the Vinnytsia National Academy of Sciences. (21008, Vinnytsia, 5/42 Soniachna St., e-mail: gav2@bio-group.net, 0687134199).

The article is devoted to the study of the issue of diagnosing the damage to the assimilation surface of tomatoes by late blight based on a detailed analysis of the activity of the plant photosystem from the standpoint of the approach to the pathogen as a stress factor in the implementation of photochemical variants of the plant signaling system. The article focuses on the peculiarities of the development of major tomato diseases in view of the specificity of plant growth and physiological processes in closed ground conditions with increasing risks of the intensity of infection and the formation of favorable conditions for the development of the pathogen due to positive gradients of temperature, humidity and ventilation of the agrocenosis. The results of a two-year cycle of research on the use of a portable fluorometer “Floratest” of Ukrainian production to find the relationship between the phenomenon of chlorophyll fluorescence and the degree of damage to the leaf apparatus of tomato plants by measuring the intensity of the process on undisturbed (undetached) leaves after their shadow adaptation for 10 minutes with graphical recording of the results at a second-by-second fixation of the process in a 90-second interval are presented.

A graded system of comparison of measurements was used with the selection of leaves of different degrees of damage from 0% damage (baseline control) to 60% damage (the maximum damage of late blight for closed ground conditions). According to the results of the averaged two-year records, a reliable sensitivity of the method for assessing the degree of stress response of the tomato leaf apparatus at the initial stages of infection with the late blight pathogen at the milestone papameter record for 3% level of damage was established in comparison with the obtained chlorophyll fluorescence curves on Kautsky curves, which were used as an absolute reference control in the experiment. Application of the basic parameters of the chlorophyll fluorescence curve (initial fluorescence (F0), plateau zone fluorescence (Fpl), maximum fluorescence Fm and steady-state fluorescence Fst) made it possible to determine the gradient response of the tomato plant photosystem to the intensification of pathogen development in the accounting scale of damage and to obtain index curves of chlorophyll fluorescence for each accounting gradation of damage. Based on the results of the evaluation of derivative indicators of chlorophyll fluorescence analysis in accordance with the provisions of the European protocol for its application, the main trends in the reaction of the assimilation system to the penetration and development of the late blight pathogen were determined. It was noted that the main effective physiological photochemical processes of the tomato leaf apparatus decreased due to an increase in the degree of damage by 1% with an average gradient of 1.35% per 1% of leaf damage with a general increase in the degree of quenching of the plant photosystem by 1.29%.

1. Pinchuk N.V., Verheles P.M., Kovalenko T.M., Okrushko S.Ie. (2018). Zahalna fitopatolohiia [General phytopathology]: Navch. posib. Vinnytsia. [in Ukrainian].

2. Kuleshov A.V., Bilyk M.O., Dovhan S.V. (2011). Fitosanitarnyi monitorynh i prohnoz: navch. Posib [Phytosanitary monitoring and forecasting: a manual]. [2–he vyd.] Kharkiv: Espada. [in Ukrainian].

3. Holiachuk Yu.S., Lisovyi M.P. (2009). Zhyttievyi tsykl hryba Phytophthora infestans (Mont) de Bary. Zbudnyk fitoftorozu v umovakh Zakhidnoho Lisostepu Ukrainy [Life cycle of the fungus Phytophthora infestans (Mont) de Bary. The causative agent of late blight in the Western Forest-Steppe of Ukraine]. Karantyn i zakhyst roslyn – Quarantine and plant protection. № 10. 12–15 [in Ukrainian].

4. Hodlevska O.O., Zaloilo I.A., Kozhemiako Ya.V., Posudin Yu.I. (2011). Zastosuvannia portatyvnoho fluorymetra dlia otsiniuvannia rezystentnosti roslyn do biotychnykh faktoriv [Application of a portable fluorometer for evaluation of plant resistance to biotic factors]. Naukovyi visnyk NUBiP Ukrainy – Scientific Bulletin of NUBiP of Ukraine. Issue 161. 217–225. [in Ukrainian].

5. Ivanov A.A., Ukladov E.O., Golubeva T.S. (2021). Phytophthora infestans: An Overview of Methods and Attempts to Combat Late Blight. Fungi. Vol. 7.P. 1071. DOI: 10.3390/jof7121071 [in English].

6. Stevenson W.R., Jones J.P., Stall R.E., Zitter T.A. (1991). Bacterial rot and Phytophthora. Compendium of Tomato Diseases. American Phytopathological. Society Press, St. Paul, 73. URL : https://www.scirp.org/ (S(i43dyn45 teexjx455 qlt3d2q))/reference/ReferencesPapers.aspx?ReferenceID=1744 936. [in English].

7. Park B, Wi S, Chung H, Lee H. (2024). Chlorophyll Fluorescence Imaging for Environmental Stress Diagnosis in Crops. Sensors. Vol. 24 (5). P. 1442. DOI: 10.3390/s24051442. [in English].

8. De Oliveira Dias F., Magalhães Valente D.S., Oliveira C.T., Dariva F.D., Copati M. G.F., Nick C. (2023). Remote sensing and machine learning techniques for high throughput phenotyping of late blight-resistant tomato plants in open field trials. International Journal of Remote Sensing. Vol. 44 (6). P. 1900–1921. DOI: 10.1080/01431161.2023.2192878 [in English].

9. Suárez J.C., Vanegas J.I., Contreras A.T., Anzola J.A., Urban M.O., Beebe S.E., Rao I.M. (2022). Chlorophyll Fluorescence Imaging as a Tool for Evaluating Disease Resistance of Common Bean Lines in the Western Amazon Region of Colombia. Plants (Basel). Vol. 11 (10). P. 1371. DOI: 10.3390/plants11101371 [in English].

10. Rolfe S.A., Scholes J.D. (2010). Chlorophyll fluorescence imaging of plant–pathogen interactions. Protoplasma. Vol. 247. P. 163–175. DOI: https://doi.org/10.1007/s00709-010-0203-z [in English].

11. Baghbani F., Lotfi R., Moharramnejad S. (2019). Impact of Fusarium verticillioides on chlorophyll fluorescence parameters of two maize lines. European Journal of Plant Pathology. Vol. 154. P. 337–346. DOI: 10.1007/s10658-018-01659-x [in English].

12. Kovyrova O.V. (2014). Metody obrobky vymiriv kryvykh induktsii fluorestsentsii khlorofilu [Methods for processing measurements of chlorophyll fluorescence induction curves]. Kompiuterni zasoby, merezhi ta systemy – Computer facilities, networks and systems. № 13. 117–124. [in Ukrainian].

13. Portatyvnyi fluorometr «Floratest» (nastanova z ekspluatatsii) (2011). [Portable fluorometer “Floratest” (instruction manual)]. Instytut kibernetyky imeni V. M. Hlushkova NAN Ukrainy. [in Ukrainian].

14. Tsytsiura Ya.H., Tomchuk O.M. (2023). Indykatsiia systemy zhyvlennia ripaku ozymoho za pokaznykamy induktsii fluorestsentsii khlorofilu [Indication of winter rape nutrition system by chlorophyll fluorescence induction]. Ahrarni innovatsii – Agrarian innovations. № 21. 110–118. DOI: 10.32848/agrar.innov. 21.17 [in Ukrainian].

15. Brestic M., Zivcak M. (2013). PSII fluorescence techniques for measurement of drought and high temperature stress signal in plants: protocols and applications. In: Rout G. R., Das A. B. (eds.) Molecular stress physiology of plants. Springer Dordrecht. P. 87–131. DOI: 10.1007/978-81-322-0807-5_4 [in English].