The study of the productivity potential of grape varieties according to the indicators of functional activity of leaves

Abstract

Photosynthetic activity in the leaf of ten grape varieties was studied in the conditions of the northern part of Forest-Steppe of Ukraine. From 2019 to 2020 meteorological data were recorded by the ‟Meteotrekˮ meteorological station. The influence of weather conditions of the spring-summer period at the beginning of the vegetation phases, which in 2019 took place on average 12 days earlier than in 2020, was noted. Analysis of changes in the induction of chlorophyll fluorescence (ICF) in leaves revealed the more efficient use of quantum energy of absorbed light by F0 in the leaves of most varieties was noted in the phase “the beginning of berry ripening”. During the three periods of the study, the varieties Aromatnyj, Zagadka, Ilichevskij rannij, and Kardishah showed a lower content of chlorophyll molecules, which do not have a functional connection with the reaction centers (RC). According to the Fp index the highest intensity of photosynthesis on average for all varieties was observed in the phase “the beginning of ovary growth”, the lowest – “the inflorescence is visible”. The potential productivity of grape plants determined by the ICF coefficient for all varieties was at a very high level and had a weak or moderate correlation with weather conditions during the growing season. The hydrothermal coefficient and Σ act t ≥10 °С had a weak effect on the efficiency of the light phase of photosynthesis (Ki) and a noticeable one (correlation coefficient r = 0.50 – 0.69) on the efficiency of dark photochemical processes (Rfd) in the leaves of most grape varieties.

Characteristics of powdery mildew [Sawadaea bicornis (Wallr.) Miyabe] influence on the photosynthetic process in Norway maple (Acer platanoides L.) seedlings

“…The effect of powdery mildew on Norway maple plants sampled from Location 1 led to an increase in the value (F p -F o )/F v by 22.2%. This parameter informs about the saturation rate of inactive reaction centres PSII responsible for water decomposition and oxygen release (Vasylenko et al 2021). An increase in (F p -F о )/F v indices indicates a violation of both energy migration and electron transport, and a decrease indicates a possible acceleration of electron transport processes.…”

The influence of powdery mildew (Sawadaea bicornis (Wallr.) Miyabe) on chlorophyll fluorescence in Norway maple (Acer platanoides L.) seedlings

“…Вплив борошнистої роси на рослини клену гостролистого з ділянки 1 призводили до зростання значення (Fp-Fо)/Fv на 22.2 %. Цей параметр інформує про швидкість насичення неактивних реакційних центрів PSII, яка відповідає за розклад води і виділення кисню (Vasylenko et al, 2021). Підвищення параметру (Fp-Fо)/Fv означає порушення як у міграції енергії, так і в транспорті електронів, а зниження свідчить про можливе прискорення електрон-транспортних процесів.…”

Fertilizers and Pesticides Impact on Surface-Active Substances Accumulation in the Dark Gray Podzolic Soils

“…Thus, the widespread use of pesticides in agricultural crops growing has turned them into a stable stressor in the agrobiotope. In addition to ensuring the necessary phytosanitary condition of crops, pesticides serve as a source of entry of ecotoxicants into the agroecosystem (Vasylenko et al, 2021;Havryliuk et al 2022a, 2022b, Ivanova et al, 2022. At the same time, it is necessary to understand that it is important not only the pollution by pesticides, their decomposition products, and related substances (surfactants) but also the reaction of the biocenosis to these stress factors.…”