Phenological Phases Research Articles

Determining of thermal time and base temperature during the reproductive phase of the Japanese plum in the tropical Andes

Climate factors affect the phenological behavior of Japanese plum (Prunus salicina Lindl.) cultivation in tropical elevation. Thermal time is more precise than chronological time for the cultivation labor program and for the estimation of crop phenological events. The objective of this study was to determine the base temperature (Tb) and thermal time for the development of the 'Horvin' plum fruit, estimating the Tb for the reproductive phenological phase of the plum. Twenty trees, consisting of ten trees per rowat two different elevations of 2,195 and 2,567 m a.s.l. (meters above sea level), in the municipality of Nuevo Colon (Colombia), were marked by locality. The appearance of each phenological stage was recorded from floral bud to harvest, estimating Tb with the minimum coefficient method of variation in function of growing degree day (GDD). The results show Tb for the phenological stages floral-anthesis with 2.84°C; anthesis-fruits set, 3.05 °C, and fruit set-harvest, 1.76°C. Therefore, this variety should be grown where there is a minimum temperature of 3.05°C during the reproductive phase. In addition, the results show that an average of 1,243.17 and 1,172.12 GDD is required to go from fruit set to fruit harvest at elevations 2,195 and 2,567 m a.s.l., respectively.

INFLUENCE OF METHODS OF BASIC TILLAGE AND FERTILIZERS ON THE YIELD OF SPRING WHEAT IN THE CONDITIONS OF AF "KOLOS" OF THE TETYUSHSKY MUNICIPAL DISTRICT OF THE REPUBLIC OF TATARSTAN

INFLUENCE OF METHODS OF BASIC TILLAGE AND FERTILIZERS ON THE YIELD OF SPRING WHEAT IN THE CONDITIONS OF AF "KOLOS" OF THE TETYUSHSKY MUNICIPAL DISTRICT OF THE REPUBLIC OF TATARSTAN

Phenological observations on the growth and development of saffron (Crocus sativus L.) in the conditions of the Right-Bank Forest-Steppe of Ukraine

There is a need to summarise information using phenological models to develop a sustainable saffron production technology with further regulation of flowering at a certain phenological stage and determination of the appropriate flowering period to improve yield and quality under different environmental conditions. The purpose of the study is to establish the course of phenological phases of saffron growth and development in the conditions of the Right-Bank Forest-Steppe of Ukraine. Phenological observations and biometric measurements were performed in the study. According to field observations, there are a total of 6 phenological stages of saffron development. The rest period lasts from the third ten days of May to October and is divided into primary and secondary dormancy. During the primary dormant period, corms do not show external morphological changes and growth, but internal physiological and morphogenetic changes occur. In the secondary dormant period, the initial emergence of leaves and flowers and their differentiation take place. During the dormant period, saffron plants were left without aboveground organs. The flowering period falls in October. The passage of this phenological stage may be affected by changes in environmental conditions or agricultural technology. The growth of the root system began with the appearance of flowers and leaves. During the growing season, the growth of the leaf apparatus and the development of the root system continue. During this period, daughter corms are also formed from the buds of the mother corm. During the winter, the replacement corms continue to grow using the nutrient reserves of the mother corm. In early March, the development of the root system slows down and the daughter corms reach almost the final size. At the end of the growing season, the root system of the mother corm stops growing. The leaves begin to age from the top to the base. By the end of May, the daughter corms are fully developed and are preparing for the transition to a dormant state. The number of corms produced per unit area depends on the age of the plot, nutrient supply, and the level of agricultural technology. Older fields produce more corms. Due to the higher density, a larger yield of stamens is formed. Therefore, understanding the phenological reactions and influence of climatic factors on the stages of saffron growth and development in certain soil and climatic conditions is useful for future forecasting of harvest time

Transferability of Machine Learning Models for Crop Classification in Remote Sensing Imagery Using a New Test Methodology: A Study on Phenological, Temporal, and Spatial Influences

Machine learning models are used to identify crops in satellite data, which achieve high classification accuracy but do not necessarily have a high degree of transferability to new regions. This paper investigates the use of machine learning models for crop classification using Sentinel-2 imagery. It proposes a new testing methodology that systematically analyzes the quality of the spatial transfer of trained models. In this study, the classification results of Random Forest (RF), eXtreme Gradient Boosting (XGBoost), Stochastic Gradient Descent (SGD), Multilayer Perceptron (MLP), Support Vector Machines (SVM), and a Majority Voting of all models and their spatial transferability are assessed. The proposed testing methodology comprises 18 test scenarios to investigate phenological, temporal, spatial, and quantitative (quantitative regarding available training data) influences. Results show that the model accuracies tend to decrease with increasing time due to the differences in phenological phases in different regions, with a combined F1-score of 82% (XGBoost) when trained on a single day, 72% (XGBoost) when trained on the half-season, and 61% when trained over the entire growing season (Majority Voting).

Seasonal development rhythm of representatives of the genus <i>Spiraea</i> L. during introduction in the European North-East of Russia (Komi Republic)

Shrubs of the genus Spiraea L. are distinguished by a great variety of ornamental features, but are still underused in ornamental horticulture in the northern territories. The issues of passing the seasonal cycle of plants under new harsh climatic conditions remain fragmentarily studied. The research was aimed at examining the features and identifying patterns of the seasonal rhythm of introduced species of the genus Spiraea L. The research was carried out on the basis of the collection of the Botanical Garden of the Institute of Biology, located in the middle taiga subzone of Komi Republic. Plants to be observed included nine species of three taxonomic sections of the genus Spiraea L. The long-term averages of phenological phases and periods of seasonal rhythm of species, as well as variability of features based on the results of phenological observations for six years in the period 2013-2018 were determined. The vegetation period of plants under new conditions lasts up to 145 days and corresponds to the vegetation period of the introduction station. Shoot growth lasts from 65 to 80 days in different species. The sequence of flowering, differences in the dates of onset and duration of flowering in different Spiraea species of three sections were noted. The duration of the prefloral period ranges from 18 to 41 %, the flowering period – from 8 to 31 % of the total vegetation period of plants. The total duration of flowering of the studied species accounts for almost 100 days. The least variability is specific for the period of vegetation of species (variability index up to 5.9 %), the greatest variability – for the period of flowering of plants (variability – up to 26.7 %). The taxonomic factor (85-91 %) was revealed to influence the passage of the generative phases of the seasonal cycle. The correlation interaction was determined between the main phenophases and the early leaf fall phase. The seasonal type of growth and phenological development of Spiraea plants is characterized by an early beginning and end of vegetation, a relatively short period of growth of shoots, and the consistency of average phenological dates. This phenorhythm of the studied species of the genus Spiraea demonstrates their potential for ornamental gardening in the northern region.

Estimating Cotton Yield in the Brazilian Cerrado Using Linear Regression Models from MODIS Vegetation Index Time Series

Satellite remote sensing data expedite crop yield estimation, offering valuable insights for farmers’ decision making. Recent forecasting methods, particularly those utilizing machine learning algorithms like Random Forest and Artificial Neural Networks, show promise. However, challenges such as validation performances, large volume of data, and the inherent complexity and inexplicability of these models hinder their widespread adoption. This paper presents a simpler approach, employing linear regression models fitted from vegetation indices (VIs) extracted from MODIS sensor data on the Terra and Aqua satellites. The aim is to forecast cotton yields in key areas of the Brazilian Cerrado. Using data from 281 commercial production plots, models were trained (167 plots) and tested (114 plots), relating seed cotton yield to nine commonly used VIs averaged over 15-day intervals. Among the evaluated VIs, Enhanced Vegetation Index (EVI) and Triangular Vegetation Index (TVI) exhibited the lowest root mean square errors (RMSE) and the highest determination coefficients (R2). Optimal periods for in-season yield prediction fell between 90 and 105 to 135 and 150 days after sowing (DAS), corresponding to key phenological phases such as boll development, open boll, and fiber maturation, with the lowest RMSE of about 750 kg ha−1 and R2 of 0.70. The best forecasts for early crop stages were provided by models at the peaks (maximum value of the VI time series) for EVI and TVI, which occurred around 80–90 DAS. The proposed approach makes the yield predictability more inferable along the crop time series just by providing sowing dates, contour maps, and their respective VIs.

A satellite-field phenological bridging framework for characterizing community-level spring forest phenology using multi-scale satellite imagery

Forest phenology, as a sensitive indicator of a forest’s response to climate change and variability, has long been monitored using remote sensing, yet has seldom been interpreted or validated with spatially compatible, community-level field phenological observations. In temperate deciduous forests, multiple spring phenological phases are critical for modeling carbon storage and biogeochemical cycles. The simultaneous detection of all these critical phenological phases at the community level remains a long-standing challenge. To tackle these challenges, the objective of this study is to develop a novel satellite-field phenological bridging framework for characterizing all key spring phenological phases of a fragmented deciduous forest using multi-scale satellite time series. The framework consists of four key components: deep learning-based spatiotemporal image fusion, satellite-based forest phenology modeling, satellite-based forest phenological metric extraction, and field-based forest community phenological characterization. With the devised framework, we extract a total of 24 satellite phenological metrics of Trelease Woods, a forest fragment near Urbana, IL, USA. From weekly field phenological observations of 148 canopy trees of 15 common species of the forest community, we devise three summative field phenological indices to characterize community-level phenological states in spring. Under the satellite-field bridging framework, events during each key spring forest phenological phase (i.e., bud swell, budburst/leafing out, leaf expansion, and leaf maturity) are successfully detected using the fusion imagery (MAE from 1.1 to 2.9 days and bias from -2.4 to 1.5 days). However, the satellite detection of the earliest field events may be influenced by understory plants, soil background, and snow. The subsequent multi-scale, satellite phenological analysis underscores the importance of taking into account spatial scale and representation from both satellite and field phenological perspectives in building corresponding bridging relationships. Among the extracted pheno-metrics, bridging the threshold-based metrics to field phenological indices results in the highest accuracy (MAE less than 3 days and bias less than 2 days). The strong agreement among the field indices demonstrates the effectiveness of our field phenological surveying approach in generating community-wide forest phenological representation. Our study innovatively scales up the field phenological observations from the individual trees to the species to the community level, and the devised framework enables accurate retrieval of all key phenological events of community-wide, spring canopy development of the forest fragment.

Phenological response of European beech (Fagus sylvatica L.) to climate change in the Western Carpathian climatic-geographical zones.

The paper analyzes the results of 26 years (1996-2021) of phenological observations of the vegetative organs of European beech (Fagus sylvatica L.) in the Western Carpathians. It evaluates the influence of the heterogeneity of this territory, including relief and elevation, based on climatic-geographical types. Phenological stages, including leaf unfolding, full leaves, leaf coloring, and leaf fall, were monitored at 40 phenological stations across eight elevation zones. The study assesses trends in the occurrence of phenological stages, the length of the growing season, and phenological elevation gradients. The results indicate a statistically significant earlier onset of spring phenological phases and delay in autumn phases, resulting in an average extension of the beech growing season by 12 days. Our findings confirm that the lengthening of the growing season due to warming, as an expression of climate change, is predominantly attributed to the warming in the spring months. The detected delayed onset of autumn phenophases was not due to warming in the autumn months, but other environmental factors influence it. The trend of elongation of the growing season (p<0.01) is observed in all elevation zones, with a less significant trend observed only in zones around 400 and 600 m a.s.l, signaling changes in environmental conditions across most of the elevation spectrum. Moreover, the heterogeneity of climatic-geographical types within each elevation zone increases the variability in the duration of the growing season for sites with similar elevations. By extending the growing season, it is assumed that the beech area will be changed to locations with optimal environmental conditions, especially in terms of adverse climatic events (late spring frosts, drought) during the growing season. The phenological elevation gradients reveal an earlier onset of 2.2 days per 100 m for spring phenophases and a delay of 1.1-2.9 days per 100 m for autumn phenophases. These findings highlight the specific environmental conditions of European beech in the Western Carpathians and their potential for anticipating changes in its original area. Additionally, these observations can aid in forecasting the further development of phenological manifestations related to climate change.

Unpunctual in diversity: The effect of stand species richness on spring phenology of deciduous tree stands varies among species and years.

Climatic drivers alone do not adequately explain the regional variation in budburst timing in deciduous forests across Europe. Stand-level factors, such as tree species richness, might affect budburst timing by creating different microclimates under the same site macroclimate. We assessed different phases of the spring phenology (start, midpoint, end, and overall duration of the budburst period) of four important European tree species (Betula pendula, Fagus sylvatica, Quercus robur and Tilia cordata) in monocultures and four-species mixture stands of a common garden tree biodiversity experiment in Belgium (FORBIO) in 2021 and 2022. Microclimatic differences between the stands in terms of bud chilling, temperature forcing, and soil temperature were considerable, with four-species mixtures being generally colder than monocultures in spring, but not in winter. In the colder spring of 2021, at the stand level, the end of the budburst period was advanced, and its overall duration shortened, in the four-species mixtures. At species level, this response was significant for F. sylvatica. In the warmer spring of 2022, advances in spring phenology in four-species stands were observed again in F. sylvatica and, less markedly, in B. pendula but without a general response at the stand level. Q. robur showed specific patterns with delayed budburst start in 2021 in the four-species mixtures and very short budburst duration for all stands in 2022. Phenological differences between monocultures and four-species mixtures were linked to microclimatic differences in light availability rather than in temperature as even comparatively colder microclimates showed an advanced phenology. Compared to weather conditions, tree species richness had a lower impact on budburst timing, but this impact can be of importance for key species like F. sylvatica and colder springs. These results indicate that forest biodiversity can affect budburst phenology, with wider implications, especially for forest- and land surface models.

Весеннее развитие черемухи обыкновенной как индикатор временных состояний ландшафтов (Свердловская область)

В статье представлены результаты исследования весеннего развития черемухи обыкновенной при проведении Единого фенологического дня 15 мая на территории Свердловской области за 2012–2023 гг. Изучение сезонного состояния вида при помощи описательного метода позволило определить географические закономерности наступления фенологических фаз и скорости продвижения явления в пространстве в пределах природных зон и подзон в зависимости от факторов окружающей среды. Выявлено более раннее развитие черемухи на юго-востоке и юго-западе области, далее фронт явления продвигается на север и северо-запад. Различия между северными и южными районами территории, в среднем, составляют 6–7 баллов. В результате наблюдений получена характеристика сезонного развития объекта, индицирующего состояние природных комплексов в краткой математической форме. Максимальное опережение развития выявлено в лесостепной зоне Русской равнины и Западной Сибири в границах исследуемого региона. В горных районах области явления наступают с заметным отставанием в 6 баллов по сравнению с равнинными. Скорость прохождения явления в разных под зонах колеблется от 0,8 до 3 баллов/100 км. Опыт такого рода многолетних исследований для других районов страны может помочь выявить тенденции влияния изменений климата на адаптационные механизмы отдельных видов растений-феноиндикаторов.

Determination of feed yield and quality parameters of whole crop durum wheat (Triticum durum Desf.) biomass under agrivoltaic system

AbstractAgrivoltaics represents a key technology for reaching sustainable development goals by reducing the competition between land used for food, for feed, and for electricity. It has been demonstrated that Agrivoltaics can increase land productivity and play a role in the expansion of renewable energy production. This work aimed to study the yield and nutritional characteristics, as well as feeding value for ruminants of Durum wheat biomass grown under agrivoltaic. Two years of controlled experiments revealed that the reduction in light moderately limited wheat yields in the phenological phase of soft dough in standard agrivoltaic trackers (i.e. with a Ground Coverage Ratio (GCR) = 13%), otherwise under extended trackers (i.e. GCR = 41%), the yields was reduced compared to control in whole light. The digestible neutral detergent fiber evaluated after 24 h of in situ rumen incubations increased with shading, resulting in different ratios of acid detergent lignin. More shaded theses also had superior crude and soluble proteins, acid detergent-insoluble protein, acid and neutral detergent fiber than the control. The biomass in the shaded treatments showed a better Ca: P ratio for ruminant nutrition. These characteristics are strategic in forage production, allowing a more flexible harvesting strategy. This additional contribution of the nutritional characteristics of Durum wheat produced on Agrivoltaic Systems could allow a better inclusion of the different types in diets and better management of silage or hay harvesting sites. These results might be helpful in improving biomass production and give valuable information on Durum Wheat under the Agrivoltaic System.

Study of the peculiarities of the main phenological growth and development phases, as well as commercial qualities of fruits of rare citrus taxa under conditions of humid subtropics of Russia

The citrus collection of the FRC Subtropical Research Center of the RAS includes 144 genotypes and contains rare species and cultivars that are of great interest for use in production, breeding, and ornamental horticulture. The research examined 13 rare taxa: Citrus aurantifolia, C. aurantifolia ‘Foro’, C.×latifolia, C.×bergamia, C. ichangensis, C. limon ‘Del Brasil’, C.×limonelloides, C.×limetta ‘Chontipico’, C. maxima ‘Sambokan’, C. medica, C. medica var. sarcodactylus, C.×meyeri, C.×myrtifolia. The research established the times and differences in the passage of the main phenological phases, namely bud opening and flower-bud formation, flowering, second and third active growth, fruit ripening. The beginning of the growing season of the studied objects was registered in the second and third decades of March; the difference between the early onset for C. aurantifolia (16.03) and the late onset for C. ichangensis (01.04) is 14–20 days. Two active growth periods were established for C. ichangensis, C. limon ‘Del Brasil’, C. maxima ‘Sambokan’, and C. medica, while the other citrus taxa under study had three periods of active growth. According to their flowering dates, taxa with early (April 11–13), middle (April 18–19), and late (April 23–28) flowering time were identified. Long flowering (29–36 days) is typical for taxa with early flowering. Remontant taxa, i. e. C. aurantifolia, C. aurantifolia ‘Foro’, C.×latifolia, C.×bergamia, C.×limonelloides, C.×limetta ‘Chontipico’, C. limon ‘Del Brasil’, C.×meyeri were identified. From the beginning of the growing season to fruit ripening, the effective heat summation was determined to be 4710–5250 ℃. The study also identified taxa with late fruit ripening, namely C. medica and C.×myrtifolia (third decade of December – first decade of January). The taxa with the best commercial qualities and biochemical composition of fruits were C. maxima ‘Sambokan’, C.×meyeri, and C.×limetta ‘Chontipico’.

Peculiarities of bacteriosis development in agrocenosis of pome fruit orchards

Goal. Was to determine ssources of bacterium diseases of pome fruits in agrocenoses and their seasonal development study and factors, which impacts on plants defeating level.&#x0D; Methods. Field (route, selective and continuous studies) and laboratory (extracting pure bacterium cultures, determining pathogenicity, identifying through the sum of morpho-cultural and their physiological and biochemical features).&#x0D; Results. There were determined the defeating peculiarities of pome fruits by bacteriosis defeating on pome fruits during the investigation in 2011—2015 and 2021—2023. Their causative agents was conformed by bacterium extraction from plant material. The most intensive bacterial necrosis happened in spring, during the period of juice intensive movement, when the tree is the most favorable to defeating. The defeating observed only on some shoots in summer (to 5% from the volume of tree crown), but the cancer development continued on the trunk’s bark. The first symptoms of fire blight observed during blossoming and at the beginning of fruit setting. The full picture opened during the shoots’ active growth. The shoots` defeating level was in the scope of 3—12% and only on some trees reached 15—18%. The fire blight strong defeat (to 55% of crown tree) observed in 2015 through the mass propagation pear-tree psylla. New fire blight sources were not identified in Chernivtsi region in 2021—2023.There were only presence of bacterial necrosis causative agent.&#x0D; Conclusions. The bacteriosis defeating determined and researched in plantations Chernivtsi and Vinnytsia regions. The highest fire blight defeating level (to 55% of crown) connected with mass propagations of pear-tree psylla. It is the main pathogen carrier. The bacterium necroses defeating depends upon the weather conditions of weather period and following the necessary level of agrotechnical measures. The investigation scheme for pome fruits bacteriosis determined developed with phenological phases terms considerations and periods of the most plants susceptibility to phytopathogens defeating.

The agroecological potential of clones of Merlot variety

The research presented in this article consists in studying the agroecological potential of the clones of Merlot wine variety (cl. 181, cl. 343, cl. 347, cl. 348, cl. 349) under the conditions of the Mereni wine-growing center, Codru region. The climate changes of recent years have brought more and more challenges to the farmers to study and better understand how high temperatures affect the vine and not only. Increasing variety diversity is an important task that involves both enhancing the quality of selection and improving the varieties themselves. This study presents the results of a research on a series of clones of Merlot grape variety. The evolution of the main phenological phases of the vine vegetation cycle was directly influenced by the climatic, pedological and topographical conditions of the area. Based on the study, it was found that in the conditions of the Mereni wine-growing area, the Codru Region, the mentioned clones of Merlot wine variety recorded a various level of significance of the difference in the values of the analyzed characters, depending on the year and the clone. The Merlot cl. 347 showed a maximum harvest of 18.08 t/ha. The Merlot cl. 348 showed a maximum sugar content of 264.5 g/dm3. The Merlot cl. 347 showed a minimum content of titratable acidity of 8.32 g/dm3.

Agricultural drought assessment in dry zones of Tolima, Colombia, using an approach based on water balance and vegetation water stress

Soil water balance is an essential element to consider for the management of droughts and agricultural land use. It is important to evaluate the water consumption of a crop in each of its phenological phases and the status of water reserves during critical hydrologic periods. This study developed an agricultural drought index (Standardized Soil Moisture Deficit Index - SMODI) conceptualized with a water balance model considering the vegetation stress caused by soil moisture deficit. This contribution was based on meteorological information, soil moisture from satellite images, hydrophysical properties of the soil and crop evapotranspiration. Information from 61 weather stations located in the dry zone of Tolima was used for estimating the water balance. SMODI was compared with the most common drought indexes: Standardized Precipitation - Evapotranspiration Index (SPEI), the Palmer Self-Calibrated Drought Index (scPDSI), and other eleven macroclimatic indexes. Pearson's correlation coefficients (r), Tukey's test, and analysis of variance were applied to analyze the degree of association between SMODI and the contrasting indexes on a quarterly basis. SMODI considers factors influencing soil moisture distribution and retention and the water stress thresholds that plants have evolved to withstand during drought periods. Consequently, this integrated approach enhances the assessment of agricultural drought by relying on pertinent physical processes. SMODI identified extremely dry, severe, moderate and normal drought 5 %, 3 %, 20 % and 72 % respectively conditions in areas characterized by Entisols, Inceptisols, and Andisols, where rice and fruit crops and pasturelands are cultivated. The SMODI has a good correlation with macroclimatic indexes (0.70 < r < 0.74).

High-resolution species distribution modelling reveals spatio-temporal variability of habitat suitability in a declining grassland bird

Abstract Context Species distribution models (SDMs) may provide accurate predictions of species occurrence across space and time, being critical for effective conservation planning. Objectives Focusing on the little bustard (Tetrax tetrax), an endangered grassland bird, we aimed to: (i) characterise the drivers of the species distribution along its key phenological phases (winter, breeding, and post-breeding); and (ii) quantify spatio-temporal variation in habitat suitability across phenological phases and over the years 2005–2021. Methods Combining remotely sensed metrics at high temporal resolution (MODIS) with long-term (&gt; 12 years) GPS telemetry data collected for 91 individuals at one of the species’ main strongholds within the Iberian Peninsula, we built SDMs (250 m resolution) for the species key phenological phases. Results The use of both dynamic and static predictors unveiled previously unknown ecological responses by little bustards, revealing a marked change in the spatial distribution of suitable habitat among phenological phases. Long-term habitat suitability trends showed considerable fluctuations, mainly in the breeding and post-breeding phases. Overall, SDM projections into the past revealed that while the species’ winter and post-breeding habitats apparently increased since 2005, suitable habitat during the species’ most critical phenological phase, breeding, apparently reduced in area over time. Conclusions Our findings show that matching remotely sensed data with GPS tracking data results in accurate habitat suitability predictions throughout the yearly cycle. Additionally, our findings stress the importance of quantifying habitat loss and its potential impact on little bustard decline over nearly 20 years. Spatio-temporal variations in habitat suitability are also identified in this work, which can help prioritize conservation areas, particularly the breeding areas that have remained stable over time, as this is a key requirement for little bustard lek breeding system.

Phenotypic variability for early drought stress resistance in tetraploid wheat accessions correlates with terminal drought performance

AbstractDurum wheat (Triticum durum Desf.) is a fundamental staple food for the countries of the Mediterranean basin. Climate change is predicted to cause a trend of increasing drought severity in this region in the near future, necessitating the improvement of durum wheat's resilience to drought stress. Using polyethylene glycol to simulate water scarcity, early vigour parameters in germinating seeds are quickly, easily and affordably assessed. Many screenings, however, only consider the seedling stage; consequently, genotypes identified as promising for cultivation in drought scenarios, may not show such features if drought appears in later phenological phases, as happens in Mediterranean climatic areas, generally prone to terminal drought. The correlation between drought stress resistance during the seedling stage (early vigour) and later stages in the life cycle is elusive due to the lack of scientific efforts. Here we used polyethylene glycol screening to classify fifty‐five tetraploid wheat accessions into three clusters (susceptible, medium resistant and highly resistant to drought), based on morpho‐physiological traits. These accessions included durum wheat cultivars and landraces, as well as ancestors like durum emmer wheat and wild emmer wheat. The results of the screenings were combined with subsequent pot experiments using nine randomly selected accessions, imposing terminal drought, and evaluating their performance. Principal component analysis was performed on data for net photosynthesis, stomatal conductance, transpiration and grain yield. Notably, the genotypes that performed best in the pot experiments were also those that performed well in the screening. Highly resistant candidates had in fact higher physiological and performance parameters than susceptible candidates. In summary, polyethylene glycol screening of germinating seeds resulted to be suitable to predictively evaluate drought resistance in tetraploid wheat accessions under terminal drought conditions, typical of Mediterranean climate zones. The reported data, thus evidence of how this inexpensive and simple method might be efficiently applied for large‐scale phenotyping.

Monitoring the phenology of plant pathogenic fungi: why and how?

Phenology is a key adaptive trait of organisms, shaping biotic interactions in response to the environment. It has emerged as a critical topic with implications for societal and economic concerns due to the effects of climate change on species' phenological patterns. Fungi play essential roles in ecosystems, and plant pathogenic fungi have significant impacts on global food security. However, the phenology of plant pathogenic fungi, which form a huge and diverse clade of organisms, has received limited attention in the literature. This diversity may have limited the use of a common language for comparisons and the integration of phenological data for these taxonomic groups. Here, we delve into the concept of 'phenology' as applied to plant pathogenic fungi and explore the potential drivers of their phenology, including environmental factors and the host plant. We present the PhenoFun scale, a phenological scoring system suitable for use with all fungi and fungus-like plant pathogens. It offers a standardised and common tool for scientists studying the presence, absence, or predominance of a particular phase, the speed of phenological phase succession, and the synchronism shift between pathogenic fungi and their host plants, across a wide range of environments and ecosystems. The application of the concept of 'phenology' to plant pathogenic fungi and the use of a phenological scoring system involves focusing on the interacting processes between the pathogenic fungi, their hosts, and their biological, physical, and chemical environment, occurring during the life cycle of the pathogen. The goal is to deconstruct the processes involved according to a pattern orchestrated by the fungus's phenology. Such an approach will improve our understanding of the ecology and evolution of such organisms, help to understand and anticipate plant disease epidemics and their future evolution, and make it possible to optimise management models, and to encourage the adoption of cropping practices designed from this phenological perspective.

Tree-ring formation dynamics in Fagus sylvatica and Quercus petraea in a dry and a wet year

European beech Fagus sylvatica and Sessile oak Quercus petraea are reaching the north-eastern limits of their natural ranges in northern Poland. According to the projected changes in potential ranges in this region, climatic conditions for both species until 2080 will remain stable. On the other hand, a decrease in the vitality of mature trees and a reduction in their radial growth are currently observed. To understand these contradictory findings, we monitored the cambial activity in both species during two vegetation seasons. 2015 was characterized by a negative water balance, while 2017 was wet. This provided an opportunity to compare how the xylogenesis proceeds in diffuse-porous beech and ring-porous oak during contrasting in the summer precipitation seasons. The forming annual increments were sampled with Presler borer at variable time intervals depending on the leaf phenological phases. The cores were prepared using a sledge microtome and double-stained with safranin and astra blue. Observations of the phases of wood formation and measurements of the width of the forming increments were analysed on the microslide digital images. Differences in the dates of the phenological phases were analysed using Two-Way ANOVA, while the dynamics of the formation of annual increments were fitted to the Single and Double Gompertz function for beech and oak, respectively. The beginning of vessel formation started earlier in both seasons compared to previous studies. Inter-seasonal differences in the duration of spring phenological phases were insignificant for both species, while inter-species differences were significant due to physiological diversity between diffuse-porous beech and ring-porous oak. In dry 2015, cambial activity ceased sooner in both species than in 2017. Differences between oak and beech were insignificant in both years, but statistically significant disparities existed within each species due to varying in precipitation seasons. Rainfall significantly elongated the duration of cambial activity and caused wider tree-rings. According to our study, despite predicted maintaining their climatic niche, both species, situated at the north-eastern cooler range boundary, are expected to produce wood at a lower rate due to the projected warmer central European climate with increased heatwaves and summer droughts.

НАГРУЗКА КУСТОВ БЕССЕМЯННЫХ СОРТОВ ВИНОГРАДА ПОБЕГАМИ И ГРОЗДЯМИ: ОБЗОР

The article considers the issue of loading bushes of seedless grape varieties with shoots and bunches in the world practice. The analysis is presented on the timing and length of pruning shoots, the load of bush by shoots, the load of bushes by bunches and methods for regulating the compactness of bunches of seedless grape varieties. The timing of pruning regulates the growth strength of shoots and the maturation time of early seedless grape varieties. Experiments on the timing of pruning often combined with subsequent treatment with growth regulators to increase yields. The length of the pruning of shoots affects the condition and death of the buds, the timing of the passage of phenological phases, productivity and quality of seedless varieties. Variety specificity and pruning dependence are noted: some varieties prefer short pruning (Perlett in India, White Seedless and Red Seedless in Iran), some – long (Beauty Seedless in India, Kishmish Batir in Uzbekistan, etc.). With an increase in the number of shoots per bush, yield capacity increase, however, the quality of grapes decreases, which also happens when the load of bunches increases. For the Jumba Seedless variety, despite the high performance with a low load of bushes with bunches, a higher one is recommended for an optimal ratio of productivity and quality. Thinning of bunches is also a common technique for regulating yield and quality, however, it is necessary to take into account the timing of thinning – too early removal of part of the inflorescences can lead to the formation of an excessively loose bunch, as in the BRS Vitoria variety in Brazil. Studies of the load of bushes of seedless grape varieties with shoots and bunches are relevant, especially in view of modern climate changes and increasing demand for high-quality products. Such studies are few in number in Russia, which requires closer study for the development of table seedless viticulture.