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Copyright of Industria Textila is the property of Institutul National de Cercetare-Dezvoltare pentru Textile si Pielarie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Compensatory growth represents the ability of plants to counteract the negative consequences of herbivore damage, contributing to the sustainable development of agriculture. Minor changes in compensatory growth due to environmental changes may significantly impact the structure and functionality of ecosystems, especially for agriculture in a semiarid region. However, there is a lack of systematic quantitative summaries and reviews on compensatory growth mechanisms, especially regarding how they might respond to global environmental changes (e.g. climate warming, drought, nutrient variation, and elevated CO2). This paper summarizes the types of physio-ecological responses of plant compensatory growth to defoliation and their characteristics through a systematic review of existing literature. The review shows that damaged plants that undergo variations in morphological and physiological traits, such as enhanced photosynthesis, increased branching, and altered biomass allocation, may mitigate injury or produce overcompensatory growth. Moderate disturbance and arbuscular mycorrhizal fungus infection rates are beneficial for overcompensation. I further discuss how plant compensatory growth is affected by global change factors, concluding that adequate nutrients and water supply are crucial factors influencing overcompensation. This summary can advance our understanding of the response patterns and mechanisms underlying plant compensatory growth, which is vital for gaining insight into the regenerative capacity of plants and promoting sustainable agricultural development under global environmental changes. [ABSTRACT FROM AUTHOR]

Chemical spraying is one of the most important and frequently performed intercultural agricultural operations. It is imperative to select the appropriate spraying technology as a selection of ineffective one leads to the wastage of a considerable volume of applied chemicals to the non-target area. Many precision technologies have been developed in the past few decades, such as image processing based on real-time variable-rate chemical spraying systems, autonomous chemical sprayers using machine vision and nozzle control, and use of unmanned aerial and ground vehicles. Cotton defoliation is a natural physiological process, but untimely and inadequate leaf defoliation by natural process hinders the mechanical cotton harvest. Induced defoliation is practiced by applying defoliants to address the issue with the natural process of defoliation. This paper covers spraying technologies in agriculture, cotton plants, cotton defoliation, new defoliant spraying systems, and the recent field test. The new spraying system attached to an autonomous mobile robot aims to improve the delivery of defoliant chemicals by adding a spray unit on the side of the plant. Preliminary results of the water-sensitive paper test at the field showed adequate penetration with low flow rates. This is a huge development as there is a huge potential to save on the cost of applying defoliant chemicals. [ABSTRACT FROM AUTHOR]

Accurately characterizing vineyard parameters is crucial for precise vineyard management and breeding purposes. Various macroscopic vineyard parameters are required to make informed management decisions, such as pesticide application, defoliation strategies, and determining optimal sugar content in each berry by assessing biomass. In this paper, we present a novel approach that utilizes point cloud data to detect trunk positions and extract macroscopic vineyard characteristics, including plant height, canopy width, and canopy volume. Our approach relies solely on geometric features and is compatible with different training systems and data collected using various 3D sensors. To evaluate the effectiveness and robustness of our proposed approach, we conducted extensive experiments on multiple grapevine rows trained in two different systems. Our method provides more comprehensive canopy characteristics than traditional manual measurements, which are not representative throughout the row. The experimental results demonstrate the accuracy and efficiency of our method in extracting vital macroscopic vineyard characteristics, providing valuable insights for yield monitoring, grape quality optimization, and strategic interventions to enhance vineyard productivity and sustainability. [ABSTRACT FROM AUTHOR]

Featured Application: Use of Geometric morphometrics tools to understand invasiveness patterns of invasive species. Simple Summary: The box tree moth is an invasive species that originated in Asia. Its presence causes damage by defoliating plants, to the point of causing their death. The presence of silk barriers and threads, covering plants during intense attacks, allows for species recognition. Cydalima perspectalis was first detected in 2007 in Germany and the Netherlands, after which it spread widely to other regions of Europe. In Croatia, its presence was first recorded in 2012 and it caused notable damage in 2013. This study analyzed the wing morphological variability of C. perspectalis in Croatia and its invasive character. This technique uses a mathematical approach in which the combination of geometry and statistics is essential to understand the morphology of invasive organisms; principally, how the wings adapt to allow the moth to colonize new environments. To achieve this, 269 moths from different areas were collected, and the wings of both males and females were evaluated. Significant differences in wing shape were found between terrestrial and coastal populations, with no sexual dimorphism established. The implications of this variability with regard to the invasive capacity and spread of the species are discussed. The box tree moth (Cydalima perspectalis Walker, 1859; Lepidoptera: Crambidae) is an invasive species naturally distributed in Asia. The caterpillars in all developmental stages cause damage through defoliation of plants, and ultimately the death of the plant itself may occur. It is possible to recognize this species by its silk barriers and threads, and in the case of an intense attack, the entire plant will be covered with them. In Europe, this species' presence was first recorded in 2007 in Germany and the Netherlands, and it is now widely distributed. In Croatia, its existence was first recorded in 2012, in Istria, while substantial damages were recorded in 2013. This work aimed to determine the morphological variability of C. perspectalis from Croatia and assess its invasive character, the possibility of flight, and the risk of further spread. The methods of geometric morphometrics were used as the analysis of wing shape. A total of 269 moths from different locations in Croatia were collected, the upper wings of males and females were analyzed using 14 landmarks. Significant differences in wing shapes between terrestrial and coastal populations were found, as well as subtle wing shape sexual dimorphism. The implications of this variability in species invasiveness and capacity of spread are discussed in this paper. We also extrapolate the usefulness of our results and suggest strategies for predicting and managing invasive species. [ABSTRACT FROM AUTHOR]

Th e paper contains the evaluation of 9 European black pine provenances on the research trial No. 41 – Roblín (Czech Republic) at the age of 51 years. Th e tested provenances originated from Bosnia and Herzegovina, Serbia, Croatia, Bulgaria, Greece, France and Slovakia. Th e evaluation is based on an assessment of following factors: total height, dbh, stem form, health state, defoliation, diameter of main branches, stem damage, crown density, twisted growth, stem nature pruning, cross-section, and taper. Obtained data sets were statistically analysed. Th e best growth both in quantitative and qualitative traits was recognised for the provenance 9 – Les Barres, Oise (France), which was excellent in height growth, health status and stem shape, and also for the Serbian provenance 2 – Crni Vrh, Titovo Užice, which excelled not only in growth rate, stem shape and health status, but also in diameter of main branches. Less suitable provenance seem to be 3 – Prušačka Rjeka, Banja Luka from Bosnia and Herzegovina (worse growth, stem nature pruning, cross-section and taper) and Croatian 5 – Južna Kandija, Osijek (worse growth, stem shape, and health). Th e most important for explaining the diff erences between provenances were the diameter at the breast height, crown density and defoliation. [ABSTRACT FROM AUTHOR]

An increase in anthropogenic load in urban complexes leads to adverse ecological changes in the environment. Urban tree stands can somewhat smooth out these shortcomings by affecting the microclimate within the local territory. According to statistical data, every year the indicator of the provision of green spaces for the residents of Kyiv decreases, which is caused by the unsatisfactory condition of street tree stands. The main purpose of this paper is to highlight the results of the study on the assortment of arboreal plants, to estimate their general condition on the busiest streets and avenues of Kyiv, and to provide recommendations for creating a perspective list of plants for urban street landscaping. The paper analyses the data of the inventory that was performed within ordinary street tree stands in 2021. It was found that the most common street tree stands include Tilia cordata, Aesculus hippocastanum, and Populus nigra. A comparative analysis of the main assortment of plants in the street tree stands of Kyiv for 2009 and 2021 was conducted, and it was established that the number of Aesculus hippocastanum and Populus nigra decreased, while the percentage of Robinia pseudoacacia, Fraxinus excelsior increased. The assessment of the general condition of plants indicates that the largest share of plants is in a satisfactory condition – 50%. The best condition was noted in Robinia pseudoacacia, Acer platanoides, and Tilia cordata. Attention is paid to the general condition of arboreal plants by the percentage of inactive photosynthetic surface. High resistance of Acer platanoides, Fraxinus excelsior, and Robinia pseudoacacia to urban conditions is revealed. The analysis of the experimental data provides grounds for determining the main and supplementary assortment of arboreal plant species recommended for use in street landscaping, with further study of their stress resistance. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central European Agriculture is the property of Journal of Central European Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista de Silvicultură şi Cinegetică is the property of Societatea Progresul Silvic / Forest Progress Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper proposes a novel technology for waste heat recovery from a coal-fired curing barn flue gas, which can reduce simultaneously the flue gas pollutants. The upper and lower shed tobacco leaves are used as the research object during the curing of tobacco leaves in the rural curing tobacco house. The temperature and the humidity are monitored during the curing process, the change in the appearance of the tobacco leaves is observed. The desulfurization and de-nitration system can improve the uniformity of the overall tobacco leaves temperature and humidity, and can realize the integration of waste heat recovery of coal-fired boilers and flue gas pollutants treatment. An experiment is carried out and the results show that the technology can save energy to the greatest extent while ensuring the quality of tobacco leaves. [ABSTRACT FROM AUTHOR]

In the context of climate change, yield and quality losses from sunburn necrosis are challenging grape growers around the world. In a previous review, we identified the role of wind speed, duration of heat exposure, drought stress and adaptation as major knowledge gaps that prevent a better predictability of sunburn events. In this paper we present results of targeted experiments aiming to close these knowledge gaps. The effects of drought stress and adaptation on sunburn susceptibility were investigated in a combined drought stress/defoliation experiment. Riesling grapevines growing in an arid climate were fully irrigated or drought stressed, and clusters were exposed to sunlight by fruit-zone leaf removal (defoliation) at two developmental stages. Sunburn symptoms were induced using infrared heaters while fruit surface temperature was measured using thermal imaging enabling the establishment of threshold temperatures. The influence of the duration of heat exposure of berries was examined by heating grape clusters to a stable temperature and monitoring the evolution of sunburn symptoms over time. To examine the effects of wind speed on the appearance of sunburn necrosis symptoms, fruit surface temperatures and sunburn severity were measured along an artificially induced wind speed gradient in two cultivars using thermal imaging and visual inspection. Longer durations of heat exposure required lower fruit surface temperatures to induce damage, while the differences in temperature after 60 min and 90 min of exposure were marginal (47.82 ± 0.25 °C and 47.06 ± 0.26 °C). Clusters of vines grown under water deficit were less susceptible to sunburn compared to those of well-irrigated plants following defoliation. The lethal temperature of clusters exposed to sunlight for seven days did not differ from those exposed to sunlight for 28 days, indicating that a full adaptation ocurred within this period. Higher wind speeds led to lower cluster temperatures and reduced sunburn severity. First evidence of a drought priming induced heat tolerance of grapevine berries was found, while adaptation had a more pronounced effect on the susceptibility to sunburn compared to water stress. [ABSTRACT FROM AUTHOR]

The coconut black-headed caterpillar (BHC), Opisina arenosella Walker (Lepidoptera: Xyloryctidae) is an important herbivore of palm trees that originates in South Asia. Over the past decades, O. arenosella has spread to several countries in Eastern and Southeast Asia. BHC larval feeding can cause severe defoliation and occasional plant death, resulting in direct production losses (e.g., for coconut) while degrading the aesthetic value of urban and rural landscapes. In this review paper, we systematically cover taxonomy, bio-ecology, invasion history and current management of O. arenosella throughout Asia. Given that O. arenosella is routinely controlled with insecticides, we equally explore options for more sustainable management through agroecological and biodiversity-based tactics e.g., cultural control or biological control. Also, recent advances in chemical ecology have unlocked lucrative opportunities for volatilemediated monitoring, mating disruption and mass-trapping. Substantial progress has been made in augmentation biological control, with scheduled releases of laboratory-reared parasitoids lowering BHC infestation pressure up to 95%. Equally, resident ants provide 75-98% mortality of BHC egg masses within the palm canopy. Biological control has been effectively paired with sanitary measures and good agronomy (i.e., proper fertilization, irrigation), and promoted through participatory farmer training programs. Our comprehensive listing of non-chemical preventative and curative tactics offer bright prospects for a more environmentally-sound, biodiversity-driven mitigation of a palm pest of regional allure. [ABSTRACT FROM AUTHOR]

Purposes: The aim of this paper was to characterize elements dynamics, including resorption before leaf shedding and accumulation/release during decomposition, of two functionally different tree species, the N-fixing, broadleaf, deciduous black locust (Robinia pseudoacacia L.), and the Mediterranean black pine (Pinus nigra Arn.), planted on recent unconsolidated volcanic deposits. Methods: In two paired, 40 years old stands, we investigated the stoichiometry of thirteen elements in green leaves, newly shed leaf litter, stable litter residue and soil. Results: Black locust leaves were richer in N, P, K, Mg and Mn; black pine needles were richer in Na, Fe, Zn, Cr, and Pb. Resorption efficiency was Pb > Zn > Fe ~ N ~ Mn ~ Mg > Cd ~ K > P in black locust, and Pb ~ Cu > Zn ~ Na > Mn > K ~ Cr in black pine. Compared to black pine, black locust newly shed litter was richer in K, Na, Mn, Cu, and Ni. During decomposition, black locust leaf litter released N, K, Mg, Na, Mn, Zn, Cu and Cd, and accumulated Fe, Ni, Cr and Pb, whilst black pine needles released N, Zn and Cd, and accumulated all the other elements. Compared to black locust black pine had a stable needle litter residue richer in all elements but N, whilst the mineral soil was poorer in all elements but Pb. Conclusions: The two functionally different tree species have distinct element dynamics from leaf to far decomposed litter. Element sequestration in the stable residue of black pine litter, likely prevents their release in the mineral soil that is thus poorer in nutrients and minor elements compared to the soil of black locust. [ABSTRACT FROM AUTHOR]

In the past, chemical thinning dominated in fruit orchards. This paper for the special issue outlines alternatives to chemical thinning for crop load management (CLM) and its effect on fruit size, firmness, sugar, starch, and weight, indicating ripeness and fruit quality, yield, and alternate bearing. A total of 450 apple trees (Malus domestica Borkh., cv. 'Roter Boskoop'; six years old) on M9 rootstock were used at the Klein-Altendorf experimental station (50° N) of the University of Bonn, Germany. As the first alternatives, trees were mechanically blossom-thinned at the balloon stage (BBCH 59) with a rotor speed of 320 rpm or 380 rpm at 5 km/h tractor speed or were chemically thinned at the full bloom stage (BBCH 65) with ammonium thiosulfate (ATS), ethephon (ETH), and/or 6-benzyladenine (BA) at 10–12 mm fruit size (BBCH 71) after applying ATS/ETH. Flower clusters and/or cluster leaves (source) were manually removed to determine the optimum sink-source ratio to achieve different ratios of fruitlets (sink) relative to the leaves (source) at fruit set (BBCH 67–69). Un-thinned, adjacent trees served as the control. The majority of CLM methods improved fruit size and weight. Removing cluster leaves at fruit set increased fruit size and weight of the remaining fruit, which has not been observed before. The most effective treatment for fruit size and weight and return bloom was the 75% flower cluster and complete cluster leaf removal. Removal of more than 50% of flower clusters successfully improved return bloom, indicative of alternate bearing. The mechanical blossom thinning had a positive effect on fruit size and weight with a return bloom similar to that of removal of 50% flower clusters. [ABSTRACT FROM AUTHOR]

Estimating foliar damage is essential in agricultural processes to provide proper crop management, such as monitoring the defoliation level to take preventive actions. Furthermore, it is helpful to avoid the reduction of plant energy production, nutrition decrement, and consequently, the reduction of the final production of the crop and economic losses. In this sense, numerous proposals support the defoliation estimate task, ranging from traditional methodologies to computational solutions. However, subjectivity characteristics, reproducibility limitations, and imprecise results persist. Then, these circumstances justify the search for new solutions, especially in defoliation assessments. The main goal of this paper consists of developing an automatic method to estimate the percentage of damaged leaf areas consumed by insects. As a novelty, our method provides high precision in calculating defoliation severity caused by insect predation on the leaves of various plant species and works effectively to estimate leaf loss in leaves with border damage. We describe our method and evaluate its performance concerning 12 different plant species. Our experimental results demonstrate high accuracy in the determination of leaf area loss with a correlation coefficient superior to 0.84 for apple, blueberry, cherry, corn, grape, bell pepper, potato, raspberry, soybean, and strawberry leaves, and mean absolute error (MAE) less than 4% in defoliation levels up to 54% in soybean, strawberry, potato, and corn leaves. In addition, the method maintains a mean error of less than 50%, even for severe defoliation levels up to 99%. [ABSTRACT FROM AUTHOR]

Unmanned aerial vehicles (UAVs) are widely used as the sprayers for low-volume pesticide application in recent years. Droplet distribution characteristics of UAV spraying in the cotton canopy have notable effect on the biological control efficacy of the targets and the defoliation efficiency of the harvest aids. In this work, the influences on droplet distribution in the cotton canopy with respect to the flight height, forward mode, and spraying volume were evaluated by conducting the field trials during two cotton growth stages in 2020, respectively. The first field trial was performed in the cotton flowering stage and the second one was conducted in the early boll development stage. Two typical UAVs equipped with a single-rotor and four-rotor, respectively, were adopted as the spraying platforms in this work. Droplet deposition obtained by water sensitive papers (WSPs) clipped on the cotton leaves was considered as the observing metric. All cotton leaves in the canopy were divided into three groups (i.e., upper, middle, and bottom layers) in both trials. Furthermore, the cotton canopy was divided as eight directions to assess the droplet distribution in the canopy from different directions. The results showed that the droplet deposition varied remarkable between the treatments and in the same canopy within a treatment. The upper layer obtained higher droplet deposition than those of the middle and bottom layers and plants P4 to P8 accessed more droplets than those of the remaining sampling plants in most treatments of both trials for the two UAVs. The upper layer droplet deposition of the four-rotor UAV treatments outperformed that of the single-rotor treatments under the same operating parameters. The forward modes rarely affected the droplet distribution of the four-rotor UAV treatments but significantly influenced that of the single-rotor UAV treatments. For the single-rotor UAV spraying with "head forward", the droplet distribution of the treatment with a flight height of 2 m was more even than that of the 1 and 3 m in the first trial. Under the same flight height, droplet deposition of the treatments with a spraying volume of 22.5 L ha-1 was remarkably higher than that of the 12 L ha-1 for both forward modes in the second trial. "Tail forward" of the single-rotor UAV treatment had better penetration at a flight height of 2 m in both trials. Therefore, for the single-rotor UAV, under a flight height of 2 m and a spraying volume of 22.5 L ha-1, "tail forward" was recommended for applying pesticides to control targets at the lower canopy and "head forward" was a better choice for harvest aid application. Four-rotor UAV was a suitable adoption for the harvest aid application and controlling the targets of the upper canopy. The results also indicate that the systemic pesticides are recommended for UAV spraying due to its uneven droplet distribution uniformity in the whole cotton canopy. [ABSTRACT FROM AUTHOR]

This paper presents research results on forest decline in Serbia. The results were obtained through monitoring defoliation of 34 tree species at 130 sample plots during the period from 2004 to 2018. This research aimed to determine whether the occurrence of defoliation and tree mortality were caused by drought. Defoliation was assessed in 5% steps according to the International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests) methodology. All the trees recorded as dead were singled out, and annual mortality rates were calculated. To determine changes in air temperature and precipitation regimes during the study period, we processed and analysed climatic data related to air temperature and precipitation throughout the year and in the growing season at 28 main weather stations in Serbia. Tree mortality patterns were established by classifying trees into three groups. The first group of trees exhibited a gradual increase in defoliation during the last few years of monitoring, with dying as the final outcome. The second group was characterised by sudden death of trees. The third group of trees reached a higher degree of defoliation immediately after the first monitoring year, and the trees died after several years. Tree mortality rates were compared between years using the Standardised Precipitation Evaporation Index (SPI) and the Standardised Precipitation Evapotranspiration Index (SPEI), the most common methods used to monitor drought. The most intensive forest decline was recorded during the period from 2013 to 2016, when the largest percentage of the total number of all trees died. According to the annual mortality rates calculated for the three observation periods (2004–2008, 2009–2013, and 2014–2018) the highest forest decline rate was recorded in the period from 2014 to 2018, with no statistically significant difference between broadleaved and coniferous tree species. As the sample of coniferous species was small, the number of sample plots should be increased in order to achieve better systematic forest condition monitoring in Serbia. The analysis of the relationship between defoliation and climatic parameters proved the correlation between them. It was noted that the forest decline in Serbia was preceded by an extremely dry period with high temperatures from 2011 to 2013, supporting the hypothesis that it was caused by drought. We therefore conclude that these unfavourable climatic conditions had serious and long-term consequences on forest ecosystems in Serbia. [ABSTRACT FROM AUTHOR]

Copyright of Lucrari Stiintifice, Universitatea de Stiinte Agricole Si Medicina Veterinara Ion Ionescu de la Brad Iasi, Seria Horticultura is the property of University of Agricultural Sciences and Veterinary Medicine (Editura Ion Ionescu de la Brad) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Studies addressing the impact of herbivory in carnivorous plants are scarce, despite loss of tissue being expected to be costly, as leaves are involved in both energy and nutrient acquisition. We evaluated the effect of simulated herbivory in a population of the carnivorous plant Pinguicula moranensis. We predicted an overall negative impact of herbivory by reducing growth, flowering probability and survivorship. Specifically, we expected that the increase in the negative effect should be related to the amount of leaf area removed.We performed simulated herbivory in plants growing in situ (2015) and ex situ (greenhouse, 2016) using a paper punch (herbivory ranging from 0 to 50%). In the ex‐situ experiment, we also tested the effect of availability of resources by implementing a prey addition trial where half of the plants were supplemented with prey (one fruit fly per week).In both experiments, our hypothesis was not supported, as growth, flowering probability and survivorship were not influenced by herbivory treatments. Plants subjected to prey addition did not show higher performance than plants deprived of prey, contradicting our prediction that availability of resources could ameliorate the effect of herbivory.Overall, the lack of differences in performance between undamaged (control) and damaged plants indicate an unexpected short‐term ability of P. moranensis to tolerate herbivory, even at high levels of damage. [ABSTRACT FROM AUTHOR]

Copyright of EPPO Bulletin is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The lack of high-quality local reproductive material, which makes it impossible to reforest large clearings after the calamity, results in the search for other suitable sources. Extensive testing of the spruce provenances in various conditions started as early as in 1960s and lasts until today. The presented study is focused on research plots from the series 1984/86–1990 with the Norway spruce’s progenies of certified units of category IIA taken within the whole territory of the Czech Republic. On two selected research plots Úsov and Jedovnice evaluation of both quantitative (tree height, DBH) and qualitative traits (stem form, stem damage, defoliation and health state) was performed. Measured provenances in young middle age growing in the conditions with a lack of precipitation showed initial growth and morphological differentiation. The highest growing stock as for the Úsov plot was achieved by provenance 46 – Janovice, Karlov pod Pradědem 2, and in the Jedovnice plot it was provenance 50 – Rožnov pod Radhoštěm, Horní Bečva. Low defoliation and overall good health state on both plots indicate resistance to external abiotic and biotic factors. In both research plots it was possible to define sets of above-average, average and below-average evaluated provenances. In summary, provenances originated from the Vysočina, Jeseníky and Beskydy mountains thrived in both plots. At the beginning of the 1980s, there was a mast year of Norway spruce, enabling the collection of seeds from 53 recognized units of category IIA (Table 1), which were considered to be the best stands in the given conditions. The obtained seeds were sown in eleven forest nurseries in the spring 1984. In the years 1986–1990, 23 research plots were established in total. The aim of the paper is to assess the variability of growth, phenotypic characteristics and health state of Norway spruce provenances in the research plots Jedovnice and Úsov at the age of 35 years. The evaluation provides an overview of the behaviour of spruce provenances in relevant site conditions and their possible grouping according to similar growth features. In all cases, 49 spruce provenances were planted on the established research plots, but four each time (different according to localities) were not planted due to the cultivation of different amounts of planting stock. Each research plot reaches a size of 1.96 ha, and the distribution of provenances was performed by a double grid system of 7 × 7 provenances with four repetitions. The plots of interest in Úsov and Jedovnice were measured in 2019 at the age of 35, where quantitative and qualitative indicators of volume production were evaluated, and resistance of provenances to abiotic harmful effects, respectively. From the biometric data, the tree height and DBH were measured. Based on the results of measurements of heights and DBH, the stem volume (o.b.) was calculated using the volume equation. The evaluation of qualitative features (stem form, stem damage, defoliation, and health state) focused on resistance to negative influences was also performed (Table 2). When comparing heights (Fig. 1 and 2) and standing volumes (Table 3 and 4), there was a significant differentiation compared to the values of DBH (Fig. 3 and 4). In the case of qualitative indicators, only slight amount of variability was observed. The health status and defoliation of spruce in the research plots point to good vitality, even though the bark calamity has already manifested itself in the surrounding forest stands. Most trees are without stem damage, but there are some provenances with prevailing damaged stems in the top part. On the Jedovnice plot, a completely straight stem form predominates, while on the Úsov plot, once slightly bent form is more pronounced. PCA method taking into account significant dendrometric and morphological features gives good results only for research plot Úsov. The data show a strong relationship between tree height, stem form and DBH, and also between health state and the number of growing individuals (Fig. 5). Partial clustering of provenances according to natural forest areas was found. The evaluation of provenance plots in Central Moravia showed that significant differentiation among provenances was found especially in heights and standing volumes. Both plots were dominated by provenances from the Vysočina, Jeseníky and Beskydy mountains. For qualitative traits, the selected characteristics have not manifested themselves significantly due to the young age of experimental material. For the next phase of research, there is supposed to add more morphological characteristics, which can be evaluated only at older age. [ABSTRACT FROM AUTHOR]

In 2021, measurements were done at two international provenance research trials for silver fir originating from the same series of experiments. The investigation was carried out in the location Vítkov and Úsov, where both trials were established. Biometric data (tree height, diameter at breast height) were measured and qualitative traits (stem shape, occurrence of stem forking, stem damage, bark pattern, and defoliation) were assessed during the early mature stage of the experiment. Overbark stem volume and per-hectare standing volume were also calculated. Sixty-five provenances of domestic and foreign origin were evaluated in both trials. Although the results do not indicate unequivocally the most suitable or most productive provenance in the trials, provenances of Czech origin including the ones originating from the surrounding natural forest areas perform consistently better than the average. The least productive provenances, on the other hand, were those from parts of Bulgaria, Austria, and especially Italy, which achieved the poorest results even in stem shape. In Czech conditions, therefore, Italian fir provenances have not proved so successful as they have in the United Kingdom. [ABSTRACT FROM AUTHOR]

Insect outbreaks can cause large scale defoliation of forest trees or destruction of crops, leading to ecosystem degradation and economic losses. Some outbreaks occur simultaneously across large geographic scales and some outbreaks occur periodically every few years across space. Parasitoids are a natural enemy of these defoliators and could help mitigate these pest outbreaks. A holistic understanding of the host-parasitoid interactions in a spatial context would thus enhance our ability to understand, predict and prevent these outbreaks. We use a discrete time deterministic model of the host parasitoid system with populations migrating between 2 patches to elucidate features of spatial host outbreaks. We show that whenever populations persist indefinitely, host outbreaks in both patches can occur alternatively (out of phase) at low migration between patches whereas host outbreaks always occur simultaneously (in phase) in both patches at high migration between patches. We show that our results are robust across a large range of parameters across different modelling approaches used typically to model intraspecific competition among hosts and parasitism, in the host-parasitoid literature. We give an analytical expression for the period of oscillations when the migration is low i.e. , when host outbreaks in both patches are out of phase, show it is in agreement with numerical results. We end our paper by showing that we get the same results whether we include the biologically rooted formulations from May et al. (1981) or a general cellular automata model with qualitative rules. • Synchrony is robust to the modelling intraspecific competition and parasitism. • Out of phase solutions are stable at low migration, time period decreases with more. • Higher migration introduces new stable solutions, destabilizing out of phase ones. • Time period for out of phase oscillations is derived which matches the numerics. • Cellular automata model mirrors synchrony seen in biologically detailed spatial host parasitoid model. [ABSTRACT FROM AUTHOR]

Fruit skin color and physical quality are important for customer acceptability and market value. Therefore, this study aimed to evaluate the effect of pneumatic defoliation on the fruit quality, coloration, and anthocyanin content of 'Fuji' apples. Apple trees were subjected to no defoliation (control) and defoliation at low (0.6 bar) and high (0.9 bar) air pressure 20 days before harvest at 1 km/h of tractor speed. High-defoliation treatment increased the leaf damage rate but did not significantly affect the defoliation rate compared to low-defoliation treatment. Additionally, photosynthetically active radiation and solar irradiance inside the tree canopies were highest in the high-defoliation group, followed by the low-defoliation and control groups. With the exception of higher firmness in the high-defoliation treatment, pneumatic defoliation treatments had little effect on fruit size and weight, titratable acidity, soluble solids content, the starch pattern index, and the sunburn incidence of fruit. Compared with that of the control group, both defoliation treatments significantly increased the a* and C values and decreased the ho values of the fruit color. Moreover, both defoliation treatments significantly increased anthocyanin content and upregulated the anthocyanin biosynthesis genes (MdPAL, MdCHS, MdCHI, MdF3H, MdANS, MdANS, MdUFGT) and the transcription factor (MdMYB10). A Pearson′s correlation analysis also showed that anthocyanin production was strongly correlated with each of the anthocyanin biosynthesis genes, especially in the pneumatic defoliation treatments. Conclusively, the results show that pneumatic defoliation at low pressure bars could be an effective strategy for improving the red coloration of 'Fuji' apples. [ABSTRACT FROM AUTHOR]

An extensive discoloration (yellowing, browning), and defoliation (leaf loss) were observed in Slovak forests during the summer of 2022. These phenomena are attributed to the combination of very low atmospheric precipitation and extremely high air temperatures from June to early August. In this study, the deterioration of forest health was analysed by comparing the image classification of Sentinel-2 satellite data from the year of intense drought occur-rence, 2022, with that from a referenced year without drought occurrence, 2020. The results indicated that in 2022, the proportion of heavily damaged stands with defoliation exceeding 50% doubled, reaching 19.3% (417,000 ha), and an area of 223,000 ha experienced an increase in defoliation by 30% or more. The damage exhibited an uneven spatial distribution, with the most significant impact observed in the western and southern parts of central Slovakia, as well as partially in the southern part of eastern Slovakia. Further GIS analyses revealed that forests growing on slopes with southern aspects suffered more severe damage than with northern exposures. However, the difference between the most damaged forests with south-southeast exposure (12.2%) and the least damaged ones with north-northwest exposure (8.2%) was only 4%. The level of damage gradually decreased with increasing altitude. Nevertheless, compared to previous studies, the damage was significantly manifested even in the fourth forest vegetation zone, up to an elevation of approximately 800 m. Regarding soil texture, which influences the water regime, the damage gradually decreased with decreasing sand content, ranging from sandy soils (17.5%) to clayey soils (6.6%). [ABSTRACT FROM AUTHOR]

Shoot branches grow from axillary buds and play a crucial role in shaping shoot architecture and determining crop yield. Shade signals inactivate phytochrome B (phyB) and induce bud dormancy, thereby inhibiting shoot branching. Prior transcriptome profiling of axillary bud dormancy in a phyB‐deficient mutant (58M, phyB‐1) and bud outgrowth in wild‐type (100M, PHYB) sorghum genotypes identified differential expression of genes associated with flowering, plant hormones, and sugars, including SbCN2, SbNCED3, SbCKX1, SbACO1, SbGA2ox1, and SbCwINVs. This study examined the expression of these genes during bud dormancy induced by shade and defoliation in 100M sorghum. The aim was to elucidate the molecular mechanisms activated by shade in axillary buds by comparing them with those activated by defoliation. The expression of marker genes for sugar levels suggests shade and defoliation reduce the sugar supply to the buds and induce bud dormancy. Intriguingly, both shade signals and defoliation downregulated SbNCED3, suggesting that ABA might not play a role in promoting axillary bud dormancy in sorghum. Whereas the cytokinin (CK) degrading gene SbCKX1 was upregulated solely by shade signals in the buds, the CK inducible genes SbCGA1 and SbCwINVs were downregulated during both shade‐ and defoliation‐induced bud dormancy. This indicates a decrease in CK levels in the dormant buds. Shade signals dramatically upregulated SbCN2, an ortholog of the Arabidopsis TFL1 known for inhibiting flowering, whereas defoliation did not increase SbCN2 expression in the buds. Removing shade temporarily downregulated SbCN2 in dormant buds, further indicating its expression is not always correlated with bud dormancy. Because shade signals also trigger a systemic early flowering signal, SbCN2 might be activated to protect the buds from transitioning to flowering before growing into branches. In conclusion, this study demonstrates that shade signals activate two distinct molecular mechanisms in sorghum buds: one induces dormancy by reducing CK and sugars, whereas the other inhibits flowering by activating SbCN2. Given the agricultural significance of TFL1‐like genes, the rapid regulation of SbCN2 by light signals in axillary buds revealed in this study warrants further investigation to explore its potential in crop improvement strategies. [ABSTRACT FROM AUTHOR]

One of the main objectives of walnut crossbreeding programmes is to produce cultivars with late leafing dates. Sixteen years ago, a walnut crossbreeding programme was initiated by Prof. Mehmet Sütyemez, and now a new walnut genotype, namely ‘Ahir Nut’, has been generated with a leafing date that starts later than all commercially-famous walnut cultivars in the world. The present study describes this walnut genotype. For a detailed analysis, ‘Ahir Nut’ was com)pared with two French-origin walnut cultivars, i.e., ‘Franquette’ and ‘Ronde de Montignac’, which have had the latest leafing dates until now. In an experimental orchard in Turkey, the leafing date in ‘Ahir Nut’ was 14 May, whereas the leafing date in ‘Franquette’ and ‘Ronde de Montignac’ were 23 April and 25 April, respectively. This approximately 3-week difference between ‘Franquette’ and ‘Ronde de Montignac’ to ‘Ahir Nut’ reveals how valuable this genotype is for walnut breeding studies. The harvest dates for ‘Ahir Nut’, ‘Franquette’ and ‘Ronde de Montignac’ were 4 October, 3 October, and 7 October, respectively. The defoliation date for ‘Ahir Nut’ was 4 December. The nut weight and kernel percentage of ‘Ahir Nut’ were calculated as 11.61 g and 49.84%, respectively. Remarkable phenological traits were found in ‘Ahir Nut’, making it a promising option for future walnut cultivation. In the present study, the late leafing date of ‘Ahir Nut’ prompted further research into the molecular and walnut crossbreeding potentials. This new genotype has been conserved as an important genetic resource for future walnut breeding programmes around the world. [ABSTRACT FROM AUTHOR]

Leaves are important 'source' organs that synthesize organic matter, providing carbon sources for plant growth. Here, we used Populus talassica × Populus euphratica , the dominant species in ecological and timber forests, to simulate carbon limitation through artificial 25%, 50%, and 75% defoliation treatments and explore the effects on root, stem, and leaf morphology, biomass accumulation, and carbon allocation strategies. At the 60th d after treatment, under 25% defoliation treatment, the plant height, specific leaf weight, root surface area and volume, and concentrations of non-structural carbohydrates in stem and root were significantly increased by 9.13%, 20.00%, 16.60%, 31.95%, 5.12%, and 9.34%, respectively, relative to the control. There was no significant change in the growth indicators under 50% defoliation treatment, but the concentrations of non-structural carbohydrates in the leaf and stem significantly decreased, showing mostly a negative correlation between them. The opposite was observed in the root. Under 75% defoliation treatment, the plant height, ground diameter, leaf number, single leaf area, root, stem, and total biomass were significantly reduced by 14.15%, 10.24%, 14.86%, 11.31%, 11.56%, 21.87%, and 16.82%, respectively, relative to the control. The concentrations of non-structural carbohydrates in various organs were significantly reduced, particularly in the consumption of the starch concentrations in the stem and root. These results indicated that carbon allocation strategies can be adjusted to increase the concentration of non-structural carbohydrates in root and meet plant growth needs under 25% and 50% defoliation. However, 75% defoliation significantly limited the distribution of non-structural carbohydrates to roots and stems, reduced carbon storage, and thus inhibited plant growth. Defoliation-induced carbon limitation altered the carbon allocation pattern of P. talassica × P. euphratica , and the relationship between carbon reserves in roots and tree growth recovery after defoliation was greater. This study provides a theoretical basis for the comprehensive management of P. talassica × P. euphratica plantations, as well as a reference for the study of plantation carbon allocation strategies in the desert and semi-desert regions of Xinjiang under carbon-limitation conditions. [ABSTRACT FROM AUTHOR]

We compared three methods for estimating current-year spruce budworm (Choristoneura fumiferana (Clem.)) defoliation from 2014 to 2021 using a network of 99 permanent sample plots in central Gaspé Peninsula, Québec. Percent current-year defoliation was measured by assessing shoots from mid-crown branches, ocular ratings of all individual trees using binoculars, and provincial government aerial surveys. Ocular survey defoliation differed from branch sample defoliation in 5–6 out of 7 years, consistently underestimating defoliation, across the full range of defoliation severity observed. Nested mixed-effect models for fir–spruce combined, balsam fir, white spruce, and black spruce ocular survey defoliation bias resulted in marginal R2 of 0.40, 0.47, 0.82, and 0.86, respectively. Current defoliation severity and its interaction with previous year defoliation and weather conditions significantly affected ocular survey bias. Correspondence of aerial survey estimates and mean plot defoliation occurred in only 43% of all plot-years and ranged from 14%–58% in individual years. Differences between aerial survey defoliation and plot values mainly resulted from assigning an adjacent class (e.g., light <30% assigned as moderate 31%–70% defoliation) or misplaced defoliation polygon boundaries, suggesting that assignment of aerial survey defoliation to plots or specific ground areas needs ground truth sampling. [ABSTRACT FROM AUTHOR]

Central African evergreen broadleaved forests around the equator exhibit a double annual cycle for canopy phenology and carbon uptake seasonality. The underlying drivers of this behavior are poorly understood and the double seasonality is not captured by land surface models (LSM). In this study, we developed a new leaf phenology module into the ORCHIDEE LSM (hereafter ORCHIDEE‐AFP), which utilizes short‐wave incoming radiation (SWd) as the main driver of leaf shedding and partial rejuvenation of the canopy, to simulate the double seasonality of central African forests. The ORCHIDEE‐AFP model has been evaluated by using field data from two forest sites and satellite observations of the enhanced vegetation index (EVI), which is a proxy of young leaf area index (LAIYoung) with leafage less than 6 months, as well as six products of GPP or GPP proxies. Results demonstrate that ORCHIDEE‐AFP successfully reproduces observed leaf turnover (R = 0.45) and young leaf abundance (R = 0.74), and greatly improve the representation of the bimodal leaf phenology. The proportion of grid cells with a significant positive correlation between the seasonality of modeled LAIYoung and observed EVI increased from 0.2% in the standard model to 27% in the new model. For photosynthesis, the proportions of grid cells with significant positive correlations between modeled and observed seasonality range from 26% to 65% across the six GPP evaluation products. The improved performance of the ORCHIDEE‐AFP model in simulating leaf phenology and photosynthesis of central African forests will allow a more accurate assessment of the impacts of climate change in tropical forests. Plain Language Summary: Evergreen broadleaved forests in central Africa near the equator have a unique behavior where their leaf growth and ability to take in carbon peak twice a year. However, the reason underlying this behavior is not well understood, and the current process‐oriented terrestrial biosphere models can not represent this double peak. In this study, we integrated a new module, which uses sunlight as the main factor for when leaves fall and new ones grow in the forest, into a popular process‐oriented terrestrial biosphere model called ORCHIDEE, to simulate this unique behavior in central African forests (hereafter ORCHIDEE‐AFP). We tested our model using real‐world data from the forests acquired at the site level and satellite images. The results show that our new model can successfully simulate when leaves change and how much carbon the forests take in. The new model demonstrates better performance than the standard model. Our improved model will be useful for predicting the future of these forests more accurately under climate change. Key Points: Solar radiation is an adequate climate factor to drive the bimodal leaf phenology of central tropical African rainforestsWe developed a new phenology scheme with solar radiation‐triggered leaf shedding and flushing for the ORCHIDEE land surface model (LSM)The ORCHIDEE LSM with the new phenology scheme captures central tropical African rainforests' bimodal leaf phenology and photosynthesis [ABSTRACT FROM AUTHOR]

Forest ecosystems within national parks are threatened by various biotic and abiotic factors. To determine the causes of the desiccation and death of trees in mixed coniferous and deciduous forests of Tara National Park (TNP), Serbia, we monitored defoliation and mortality of individual trees in permanent experimental plots. Data on the desiccation of a large number of trees were gathered by determining the total volume of dry trees and areas of forests under drying stress. The two sets of data were combined to determine the impact of climatic events, primarily drought periods, on the desiccation of forests. Combining data from the International Co-operative Program on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests) with TNP data helped relate forest desiccation to climate events. Key climate signals were identified by monitoring tree defoliation changes in two permanent experimental plots, and then assessed for their influence on tree desiccation in the entire national park. The standardized precipitation evapotranspiration index (SPEI) was used for a more detailed analysis of the drought period. Despite the lack of climate data for a certain period, the SPEI index revealed a link between climate variables and the defoliation and desiccation of forests. Furthermore, the desiccation of trees was preceded by a long drought period. Although mixed coniferous-deciduous forests are often considered less vulnerable to natural influences, this study suggests that forest ecosystems can become vulnerable regardless of tree species composition due to multi-year droughts. These findings contribute to a better understanding of important clues for predicting possible future desiccation of forests. Continuous monitoring of the state of forests and of more permanent experimental plots in national parks could provide better quality data and timely responses to stressful situations. [ABSTRACT FROM AUTHOR]

Defoliation is an inevitable abiotic stress for forage and turf grasses because harvesting, grazing, and mowing are general processes for their production and management. Vegetative regrowth occurs upon defoliation, a crucial trait determining the productivity and persistence of these grasses. However, the information about the molecular regulation of this trait is limited because it is still challenging to perform molecular analyses in forage and turf grasses. Here, we used rice as a model to investigate vegetative regrowth upon defoliation at physiological and molecular levels. This study analyzed stubble and regrown leaves following periodic defoliation using two rice varieties with contrasting regrowth vigor. Vigorous regrowth was associated with maintained chlorophyll content and photosystem II performance; a restricted and promoted mRNA accumulation of sucrose synthase (SUS) I and III subfamilies, respectively; and reduced enzymatic activity of SUS. These results suggest that critical factors affecting vegetative regrowth upon defoliation are de novo carbohydrate synthesis by newly emerged leaves and proper carbohydrate management in leaves and stubble. Physiological and genetic analyses have demonstrated that the reduced sensitivity to and inhibited biosynthesis of cytokinin enhance regrowth vigor. Proper regulation of these metabolic and hormonal pathways identified in this study can lead to the development of new grass varieties with enhanced regrowth vigor following defoliation. [ABSTRACT FROM AUTHOR]

Fatsia japonica plays an important role as a commonly used plant in urban landscaping. From 2022 to 2023, a root rot infestation was observed that caused extensive wilting of Fatsia japonica without leaf shedding and eventual death of the plant, severely reducing the ornamental qualities of the plant as well as the vigor of its growth. Fusarium species were isolated from the roots of the affected plants, exhibiting abundant and dense yellow mycelial colonies that proliferated radially from the center of the Petri dishes. Morphological examinations revealed the presence of falciform macro- and microconidia consistent with Fusarium, as well as chlamydospores characterized by their thick walls. For further identification, the amplification and sequencing of the ITS, TEF1 alpha, and RPB2 alpha genes were performed. Finally, healthy Fatsia japonica plants were inoculated with a spore suspension of the pathogen, to confirm that the disease symptoms were compatible with naturally occurring infection. Fusarium vanettenii was identified as the causative agent of Fatsia japonica root rot. To the best of our knowledge, this is the first report of F. vanettenii causing root rot of Fatsia japonica in China. [ABSTRACT FROM AUTHOR]

The preservation or removal of apical meristem in Leymus chinensis is contingent upon grazing intensity and has a significant impact on above‐ and belowground biomass, nutritive value, and sustainability of L. chinensis grassland. However, this topic remains understudied. Therefore, a manipulative trial was conducted to induce grazing defoliation through mowing, where two post‐grazing heights (preservation or removal of the apical meristem) and four pre‐grazing plant heights (i.e., 18, 24, 31, and 35 cm) are combined factorially to create gradients of grazing intensities, resulting in a total of eight treatments. Additionally, two identical control treatments are also incorporated. Our results showed that apical meristem removal at various pre‐grazing heights resulted in varying degrees of increased grazing intensities, thereby enhancing the nutritive value of L. chinensis. However, this practice also led to detrimental effects on the plant's carbohydrates reserve as well as herbage mass. The results indicated that although defoliation in treatments involving apical meristem removal resulted in the highest number of frequent cuttings, it did not confer any advantages in terms of herbage mass and nutrient preserves, except for herbage nutritive values when compared to treatments involving apical meristem preservation. The apical meristem preservation treatments demonstrated the highest CP yield over a 2‐year period compared to the apical meristem removal treatments. Furthermore, within these apical meristem preservation treatments, only when the pre‐grazing height is 35 cm and post‐grazing height is 17 cm, there is no significant decrease in above‐ and belowground biomass. This establishes this specific defoliation regime as an optimal and effective management strategy for L. chinensis grassland. [ABSTRACT FROM AUTHOR]

Seedlings of two species of mangroves, Bruguiera gymnorrhiza and Rhizophora apiculata, were monitored for 8 years on the Pacific island of Kosrae, Federated States of Micronesia, to determine the effects of canopy cover and hydrogeomorphic zone on long-term survival and growth. Annual rainfall is high with little seasonality. Study plots with seedling subplots were in fringe, riverine, and interior hydrogeomorphic zones along four small rivers. The height of each seedling was measured each year and was designated each time as being under an open, partially closed, or closed canopy. Growth rates of both species were slow, and no seedling that was newly established during the study became a sapling (2 m). Many seedlings stopped growing for long periods of time. Bruguiera seedlings were more numerous than Rhizophora seedlings. They grew faster than Rhizophora seedlings except in riverine zones. Predicted growth rates of Bruguiera were fastest under an open canopy and slowest under a closed canopy, but Rhizophora was not affected by canopy status. Overall mortality rates for the two species were similar, averaging 36% year−1. El-Niño-Southern Oscillation events did not affect growth or mortality but may have caused some defoliation. [ABSTRACT FROM AUTHOR]

Background: Northern ecosystems are strongly influenced by herbivores that differ in their impacts on the ecosystem. Yet the role of herbivore diversity in shaping the structure and functioning of tundra ecosystems has been overlooked. With climate and land-use changes causing rapid shifts in Arctic species assemblages, a better understanding of the consequences of herbivore diversity changes for tundra ecosystem functioning is urgently needed. This systematic review synthesizes available evidence on the effects of herbivore diversity on different processes, functions, and properties of tundra ecosystems. Methods: Following a published protocol, our systematic review combined primary field studies retrieved from bibliographic databases, search engines and specialist websites that compared tundra ecosystem responses to different levels of vertebrate and invertebrate herbivore diversity. We used the number of functional groups of herbivores (i.e., functional group richness) as a measure of the diversity of the herbivore assemblage. We screened titles, abstracts, and full texts of studies using pre-defined eligibility criteria. We critically appraised the validity of the studies, tested the influence of different moderators, and conducted sensitivity analyses. Quantitative synthesis (i.e., calculation of effect sizes) was performed for ecosystem responses reported by at least five articles and meta-regressions including the effects of potential modifiers for those reported by at least 10 articles. Review findings: The literature searches retrieved 5944 articles. After screening titles, abstracts, and full texts, 201 articles including 3713 studies (i.e., individual comparisons) were deemed relevant for the systematic review, with 2844 of these studies included in quantitative syntheses. The available evidence base on the effects of herbivore diversity on tundra ecosystems is concentrated around well-established research locations and focuses mainly on the impacts of vertebrate herbivores on vegetation. Overall, greater herbivore diversity led to increased abundance of feeding marks by herbivores and soil temperature, and to reduced total abundance of plants, graminoids, forbs, and litter, plant leaf size, plant height, and moss depth, but the effects of herbivore diversity were difficult to tease apart from those of excluding vertebrate herbivores. The effects of different functional groups of herbivores on graminoid and lichen abundance compensated each other, leading to no net effects when herbivore effects were combined. In turn, smaller herbivores and large-bodied herbivores only reduced plant height when occurring together but not when occurring separately. Greater herbivore diversity increased plant diversity in graminoid tundra but not in other habitat types. Conclusions: This systematic review underscores the importance of herbivore diversity in shaping the structure and function of Arctic ecosystems, with different functional groups of herbivores exerting additive or compensatory effects that can be modulated by environmental conditions. Still, many challenges remain to fully understand the complex impacts of herbivore diversity on tundra ecosystems. Future studies should explicitly address the role of herbivore diversity beyond presence-absence, targeting a broader range of ecosystem responses and explicitly including invertebrate herbivores. A better understanding of the role of herbivore diversity will enhance our ability to predict whether and where shifts in herbivore assemblages might mitigate or further amplify the impacts of environmental change on Arctic ecosystems. [ABSTRACT FROM AUTHOR]

Alternaria solani is the second most devastating foliar pathogen of potato crops worldwide, causing premature defoliation of the plants. This disease is currently prevented through the regular application of detrimental crop protection products and is guided by early warnings based on weather predictions and visual observations by farmers. To reduce the use of crop protection products, without additional production losses, it would be beneficial to be able to automatically detect Alternaria solani in potato fields. In recent years, the potential of deep learning in precision agriculture is receiving increasing research attention. Convolutional Neural Networks (CNNs) are currently the state of the art, but also come with challenges, especially regarding in-field robustness. This stems from the fact that they are often trained on datasets that are limited in size or have been recorded in controlled environments, not necessarily representative of real-world settings. We collected a dataset consisting of ultra-high-resolution modified RGB UAV-imagery of both symptomatic and non-symptomatic potato crops in the field during various years and disease stages to cover the great variability in agricultural data. We developed a convolutional neural network to perform in-field detection of Alternaria, defined as a binary classification problem. Our model achieves a similar accuracy as several state-of-the-art models for disease detection, but has a much lower inference time, which enhances its practical applicability. By using training data of three consecutive growing seasons (2019, 2020 and 2021) and test data of an independent fourth year (2022), an F1 score of 0.93 is achieved. Furthermore, we evaluate how different properties of the dataset such as its size and class imbalance impact the obtained accuracy. [ABSTRACT FROM AUTHOR]

The efficacy of using a synthetic (azoxystrobin + difenoconazole), copper-based (copper oxychloride) and low-content copper compound (copper complexed with gluconate and lignosulphonate) fungicides for controlling Venturia oleaginea, the causal agent of olive spot disease, was evaluated in an olive (cv. Nabali) orchard located in the Kafr Qud area (Palestine) in 2017–2018. Treatments were applied at three different times (February, April, and August). In January 2017, at the beginning of the experiment, about 90% of the leaves grown in 2016 were infected. Defoliation was determined by counting the leaves on the labeled branches initially and then periodically. It increased gradually in both the control and treated trees, but those treated with azoxystrobin + difenoconazole or with copper complexed with gluconate and lignosulphonate showed a slower defoliation rate. During 2017, new shoots grew and new leaves developed. All treatments reduced the drop of new leaves with respect to the control, with positive effects on the reproductive activity (inflorescence growth and yield). Overall, all treatments significantly reduced the disease, thus indicating the possibility of greatly reducing infections if treatments are regularly applied each year, also with traditional (copper-based) fungicides. Due to their capability of penetrating inside the vegetative tissue, azoxystrobin + difenoconazole or copper complexed with gluconate and lignosulphonate reduced/slowed down the drop of infected leaves. The use of these fungicides is therefore particularly recommended when olive leaf spot disease is severe. The use of low-content copper compounds allows the amount of metallic copper used for the treatments against V. oleaginea to be greatly reduced. [ABSTRACT FROM AUTHOR]

Using chemical defoliants to remove cotton leaves represents a groundbreaking shift in cotton cultivation. The mechanization of cotton harvest is increasing, but a substantial amount of foliage that remains on the plant even at maturity is the major barrier for mechanical harvest. Properly completing mechanical and manual harvests requires artificial leaf detachment through defoliants. Still there is no proper defoliant concentration, application times and mechanism of action available. Therefore, the present study aimed to find an effective defoliant and application time to enhance mechanical harvest efficiency, along with a clear description of the mechanism of actions in cotton CO17 (Gossypium hirsutum). The field experiment was conducted during the year 2019-20 and used five concentrations of Thidiazuron defoliant (100, 150, 200, 250 and 300ppm) and Ethephon@0.5% (T2) in cotton variety CO17 to study the physiological, biochemical and hormonal responses at 120, 127 and 134 days after sowing. As a result, the concentrations of plant growth hormones, indole-3 acetic acid (4.9 fold), zeatin (32.7%) and gibberellic acid (7 fold) reduced. In contrast, abscisic acid (48.6%), jasmonic acid (34.9%), salicylic acid (2.15 fold) increased in the T7- Thidiazuron + Diuron (300 ppm) treatment followed by T5-Thidiazuron + Diuron (200 ppm). Additionally, the antioxidant enzymes ascorbate peroxidase, peroxidase, catalase, superoxide dismutase, cellulase in leaves, petiole and bolls were decreased due to defoliant T5- Thidiazuron + Diuron (200 ppm) followed by T7-Thidiazuron + Diuron (300 ppm), indicating that the hormone concentration, antioxidative and hydrolytic enzymes are ruled out and forces the defoliation process. [ABSTRACT FROM AUTHOR]

This study sheds light on the remarkable physiological adaptations that the Cenostigma pyramidale makes, particularly during periods of extreme water scarcity, and their remarkable ability to rebound when a new rainy season arrives. C. pyramidale employs a survival strategy to mitigate the adverse effects of water shortage and then endures challenging environmental conditions and sustaining vital functions. Previously, this species was classified as deciduous since it retained at least 40% of its leaves to sustain basal gas exchange rates. The discrepancy in classification arises from differences in study methodologies, with this research being conducted in the field under natural conditions. This study demonstrates a negative correlation between rainfall and specific leaf area (SLA), highlighting that plants with smaller SLA are more drought-tolerant. Changes in leaf anatomy, including an increase in palisade parenchyma and reduction in spongy tissue, serve as adaptive strategies to enhance photosynthesis under water stress conditions. Hydraulic conductance plays a crucial role in plant adaptation to water scarcity. An intricate interplay between leaf anatomy and hydraulic conductance is observed, with adjustments in xylem characteristics influencing leaf gas exchange. The phenotypic plasticity is high in C. pyramidale, demonstrating the species' ability to adapt to changing environmental conditions. In summary, this study illuminates the multifaceted strategies employed by plants to cope with water scarcity, from leaf shedding to anatomical and physiological adaptations, highlighting the resilience of native species in arid environments. These findings offer valuable insights into plant responses to environmental stress and their ability to thrive in challenging conditions. [ABSTRACT FROM AUTHOR]

In recent years, severe hailstorms have caused damage to cotton leaves and stalks. In order to identify the effects of cotton leaf damage on its dry matter accumulation, protective enzyme activity and yield in different periods, in this experiment, different intensities of hail were simulated by manual leaf cutting. In this study, the effects of leaf damage on dry matter accumulation, chlorophyll fluorescence, POD (peroxidase), SOD (superoxide dismutase) and MDA levels (malondialdehyde), and yield of cotton were studied in field experiments at three stages (bud, full bud and flower boll stages) and in sub-plots with different artificial defoliation intensities (0%, 25%, 50%, 75% and 100%). Removing the leaf sources had differently sized effects on the "sink" at each stage, and these are ordered as follows: flowering and boll stage > full bud stage > pregnancy stage. The greater the intensity of leaf removal, the greater the impact on the "sink". Among them, after removing 50% of the leaves at the full bud stage, the total dry matter of the cotton plant increased by 12.46% compared to that of the control, and the boll formation rate per plant increased by 14.99%, resulting in overcompensation. Mo, Vj and φDo all showed a tendency to decrease and then increase with the increase in defoliation intensity at different periods of the treatment, and the lowest values of Mo, Vj and φDo, and the largest values of φpo, ψo and φEo were found in the 50% defoliation treatment at the gestational bud stage. The values of ψo and φEo were at the maximum in the 25% defoliation treatment at the full bud stage. The values of Mo and Vj in the different defoliation treatments at the bolling stage showed a tendency to increase and then decrease with the increase in defoliation intensity, with the highest values in the 25% treatment and the smallest values of φpo, ψo and φEo in the 25% defoliation treatment. The POD enzyme activity level was elevated in the defoliation treatments at the three different periods, and the highest value was observed in the 50% defoliation group at the full bud and boll stages, which is a reflection of supercompensation. The SOD enzyme activity level tended to increase with the intensity of defoliation, and defoliation at the gestational and full bud stages first enhanced and then weakened the stress on the cotton plants. The differences between treatments decreased after 12 weeks. The stress of defoliation on cotton plants was weakened at the boll stage. With the increase in defoliation intensity, the content of MDA showed a gradual increasing trend. The cotton MDA content was higher than that of the other treatments at 75% defoliation at both the post-fertilized bud and full bud stage. [ABSTRACT FROM AUTHOR]

Objective: To determine the productive performance and forage consumption (Trifolium repens L.) of Mexican Creole and Sasso chickens, under two rearing systems (confinement or grazing). Design/Methodology/Approach: One-hundred twenty-eight chickens (64 Mexican Creole (MC) and 64 Sasso (S)) of 35 d of age were randomly distributed in two production systems to obtain four repetitions (eight chickens per repetition) of each of the following genotype × system combinations: Mexican Creole in grazing, Mexican Creole in confinement, Sasso in grazing, and Sasso in confinement. A completely randomized experimental design with a 2×2 factorial arrangement was used, with genotype and production system as its main factors. The following variables were evaluated: feed consumption, weight gain, and feed conversion. Additionally, forage consumption in grazing birds was determined. Results: The productive performance variables were not affected by the production system factors or by its interaction with the bird genotype. However, the genotype did influence the variables considered: the Sasso birds recorded better values (p≤0.05) than Mexican Creole specimens. Regarding forage consumption, no differences were observed (p≤0.05) between bird genotypes and, in both cases, the accumulated consumption at the 49 d of study was close to 60 g of DM. Study Limitations/Implications: It is necessary to carry out a socioeconomic study as well as a defoliation level analysis with the aim of improving the use of the resource. Findings/Conclusions: Mexican Creole birds had a lower productive performance with a similar forage consumption. [ABSTRACT FROM AUTHOR]

The palaeoecology of Ginkgo through deep time, including its ecophysiology and heterophylly, remains poorly understood due to the limitation of quantitative methods. In this paper, we report well-preserved leaves of Ginkgo henanensis sp. nov. from the Paleocene Dazhang Formation of Luanchuan, Henan Province, China. Our understanding of the ecophysiology and heterophylly of the genus has been improved by the discovery. These fossils are distinguished by heterophyllous leaves that can range in morphology from bilobed to multi-lobed forms. Thus, unlike other Cenozoic Ginkgo with entire-margined leaves, this is the first well-established Cenozoic taxon that has exclusively lobed leaves similar to Mesozoic-type ginkgos. A useful leaf ecophysiological functional trait that offers quantitative insights into morphological heterophylly and the mechanism of leaf shape selection is the dry leaf mass per area (LMA) of Ginkgo. Leaf shape changes, including the evolution of heterophylly, are linked to functional adaptation. There are two groups of LMAs for four fossil G. henanensis specimens: 120.9 g/m2 to 131.3 g/m2, and 184.5 g/m2 to 187.4 g/m2. The results of the reconstructed fossil LMAs, which serve as quantitative evidence of G. henanensis ' heterophylly, also point to the existence of various leaf survival strategies within G. henanensis. Additionally, both groups of G. henanensis have LMAs that are higher than those of extant Ginkgo biloba , indicating that this species has a slower return ecological strategy than its current equivalent. This strategy may have helped to decrease the rate of nutrient cycling, which supported Ginkgo to thrive in a wider variety of ecological niches in the Paleocene than it does today. These findings close a knowledge gap in the evolution of Ginkgo. • Species similar to the Mesozoic multilobed Ginkgo still present in the Paleocene. • The feasibility of existing methods to reconstruct the leaf mass per area of fossil Ginkgo is tested. • Heterophylly of fossil Ginkgo are quantitatively proved. [ABSTRACT FROM AUTHOR]

Insect pollinators are in population decline due to environmental and chemical stressors. Including native forbs in pastures could benefit grazers and pollinators; however, their forage and flowering characteristics are not fully documented. The objectives of our research were to evaluate 12 native forbs for persistence, forage mass, nutrient composition, and flowering patterns under repeated defoliation. Twelve species were planted in a small-plot experiment in 2018. Response variables were measured from 2020 to 2022. Annual (partridge pea, PPEA, Chamaecrista fasciculata) and biennial (black-eyed Susan, BESU, Rudbeckia hirta) species established high (p < 0.05) plant populations during the first season; however, the PPEA declined (p < 0.05) in forage mass during 2021. Tall species (Maximilian sunflower, MSUN, Helianthus maximiliani; cup plant, CUPP, Silphium perfoliatum) increased in forage mass, produced high-quality forage, and flowered during early fall. Lanceleaf coreopsis (LCOR, Coreopsis lanceolata) produced consistent (p > 0.05) forage mass and flowered in spring. The purple coneflower (PURC, Echinacea purpurea), Illinois bundleflower (ILBF, Desmanthus illinoensis), and oxeye sunflower (OSUN, Helopsis helianthoides) produced high-quality, consistent (p > 0.05) forage mass and flowered mid-season. Interseeding the BESU, ILBF, PPEA, LCOR, PURC, OSUN, and MSUN or CUPP would produce high-quality forage and floral resources throughout summer. [ABSTRACT FROM AUTHOR]