Search Results (31)

Plum pox virus (PPV) is one of the most destructive pathogens affecting stone fruit trees. It causes sharka disease and severe yield losses. The genetically modified plum cultivar ‘HoneySweet’ was developed to provide long-lasting resistance to PPV via RNA interference. Long-term field trials of ‘HoneySweet’ have been conducted in the Czech Republic since 2001, involving the artificial inoculation of the cultivar with PPV alone, and with apple chlorotic leaf spot virus (ACLSV) and prune dwarf virus (PDV) in combination. This study evaluates the impact of viral infection on tree growth after 24 years in the field. Growth parameters—trunk cross-sectional area (TCSA) and canopy volume—were measured and analysed using ANOVA and Tukey’s test. The results show that infected trees exhibit significantly reduced growth compared to non-infected controls, with the strongest inhibition observed in trees inoculated with PPV + PDV + ACLSV. The presence of ACLSV had the most pronounced negative effect on growth, while PDV did not significantly influence tree vigour. These findings emphasise the importance of using virus-free rootstocks and certified planting material to prevent growth suppression in HoneySweet orchards. Full article

Hyperspectral images, characterized by rich spectral information, enable precise pixel-level classification and are thus widely employed in remote sensing applications. Although convolutional neural networks (CNNs) have demonstrated effectiveness in hyperspectral image processing, their limited receptive fields constrain their capacity to capture long-range dependencies. Transformers excel at modeling long-range features for hyperspectral image classification (HSIC). Yet, they often overlook effective representation of local spectral–spatial characteristics while incurring computational redundancy from numerous classification-irrelevant tokens. To address these challenges, we propose EDTST, a state-of-the-art Vision Transformer architecture specifically designed for efficient hyperspectral image classification. The model utilizes a large-kernel 3D convolution block to extract deep spectral–spatial features. A 2D convolution block further refines these features, followed by a novel attention mechanism with dynamic token pruning that substantially reduces the computational load by focusing on the most pertinent features. The process concludes with an adaptive average pooling layer and a fully connected layer for classification. Extensive experiments on four standard hyperspectral datasets demonstrate that EDTST achieves the highest classification accuracy, with a notable 3% improvement in overall accuracy on the WHU-Hi-HanChuan dataset, while requiring the shortest training and inference time among all compared state-of-the-art models from the past three years. These results validate the efficacy of our approach in achieving superior performance with markedly improved computational efficiency. Full article

The exponential increase in global plastic production, reaching over 380 million tons in recent years, has exacerbated environmental problems, particularly in agriculture. Agricultural residues, such as hazel (Corylus avellana L.) pruning and plastic wastes, are underutilized resources that can be transformed via pyrolysis into biochar. This study focuses on copyrolyzed biochar produced from hazel biomass and polyethylene and aims to evaluate its effect on the water retention properties of degraded Alfisol. Van Genuchten’s hydrological model was used to analyze parameters such as rapid drainage pores, plant-available water pores, and air capacity (AC) under varying particle sizes (small and large) and application rates (1% and 5% w/w). The results revealed that fine particles at higher doses (5%), especially in P-5%-large and P-5%-small, considerably improved plant-available water retention, particularly within micropores and mesopores. Microstructural modifications induced during pyrolysis enhanced the water retention capabilities of biochar copyrolyzed with plastic. However, its effects on AC and pore connectivity warrant further investigation to assess long-term soil functionality. By integrating waste valorization with improved agricultural practices, this study underscores the potential of biochar copyrolyzed with plastic as an amendment for degraded soil. However, the long-term stability of this amendment requires further study. Full article

Pitaya (Selenicereus undatus) is a long-day climbing cactus that blooms in waves mostly on 1-year old, succulent leafless shoots called cladodes. Nonetheless, pitaya can also bloom on new-year growth if the buds of the cladodes are mature enough and competent for flower induction. Here, we tested, during two consecutive years, whether early pruning could have a positive effect on promoting more flowering waves, better fruiting, and heavier yield of ‘Korean White’ pitaya cultivated in unheated greenhouses of Southeastern Spain. The results show that pruning in January instead of March did not consistently modify the reproductive behavior of ‘Korean White’ pitaya in our conditions. Therefore, no significant effects on the number of blooming waves, flowering intensity, fruit set, quality or yield were observed. The only positive effect, not always significant, was an increase in fruit size that led to better fruit distribution into commercial categories in one out of the two experimental seasons. The lack of effect of early pruning was attributed to the prevalent low temperatures during winter in Spain. The results, however, suggest it is worthwhile exploring whether greenhouse heating with temperatures above pitaya’s base temperature may have the desired effects on increasing blooming waves. The profitability of this practice have to be carefully assessed. Full article

This study investigated the influence of cane diameter on vegetative, productive, and physiological behaviors in Actinidia chinensis, cv. Gold 3. Conducted over two years (2021–2022), the experiment compared canes with larger (HD) and smaller (LD) proximal diameters. This research focused on parameters such as shoot morphology, leaf gas exchange, fruit quality, and hydraulic resistance. The results revealed that HD canes promoted more vigorous growth, with a higher proportion of long and medium shoots, whereas LD canes resulted in shorter shoots. Additionally, the HD canes demonstrated a higher leaf area and more extensive leaf coverage, contributing to enhanced photosynthetic activity, as evidenced by enhanced gas exchange, stomatal conductance, and transpiration rates. This higher photosynthetic efficiency in HD canes resulted in more rapid fruit growth, with a larger fruit size and weight, particularly in fruits from non-terminate shoots. By contrast, fruits on LD canes exhibited slower growth, particularly in terms of fresh weight and dry matter accumulation. Despite these differences, maturation indices, including soluble solids and acidity levels, were not significantly affected by cane type. The findings suggest that selecting HD canes during winter pruning could lead to earlier harvests, with improved fruit quality and productivity, making this practice beneficial for optimizing vineyard management in Actinidia chinensis. Full article

Seed orchards play important roles in supplying good seeds. Miniature orchards have the advantages of reducing management areas, but rapid crown development will decrease light intensity and seed production. Block-rotation cycles within an orchard need to be evaluated to optimize total seed production per unit time and area. The development of tree height and primary branches, as well as spatial light variation over the years after pruning and defoliation manipulation were evaluated in a miniature orchard of Chamaecyparis obtusa (Sieb. et Zucc.) Endl. set on the Pacific side of Japan. Just two years after manipulation, the branches of the upper-crown parts had grown so long that they were touching each other, and the light environments of the lower-crown parts had become drastically darker. Next, based on the crown development and light variation and the relationship between cone production and light intensity, we performed a simulation of total cone production over the years in a hypothetical orchard composed of multiple blocks. Then, the simulated total cone production was compared between the block-rotation cycles, where crown management was performed every three or four years. Compared to the three-year block rotation, the distribution of within-tree cone production for the four-year block rotation was more biased towards only the upper crown, since the lower crown became suddenly darker. It was estimated that cone production for the entire tree and the entire seed orchard would be lower than in the three-year block rotation. The approach and findings of this study will be useful for improving seed orchard management. Full article

The European hazelnut is a temperate nut crop, often managed as a multi-stemmed shrub due to its natural aptitude to produce several suckers at the base of the stump, depending on variety. Traditional hazelnut-growing regions such as Italy, Turkey, and Spain typically adopt this architecture, while other hazelnut-producing countries such as the USA, France, and Chile increasingly use single-trunk systems to facilitate orchard management. Multi-stemmed plants allow gradual renewal through sucker selection but may lead to excessively dense canopies, reducing the effectiveness of pest and disease control, increasing biennial bearing, and lowering nut yields in vigorous cultivars. In order to drive the ongoing enlargement of hazelnut cultivation, attempts in designing high-density (HD), and more occasionally super-high-density (SHD), hazelnut orchards are on-going, although these are poorly explored in terms of suitable plant training systems, such that, sometimes, multi-stemmed plant shapes are used; otherwise, single-trunk solutions are adopted. In order to explore new hazelnut planting and training solutions focused on sustainable intensification, a trial was established in 2019 in central Italy to evaluate the eligibility of three training systems (treatment A: regular four-stemmed shrub; treatment B: single-trunk sapling; treatment C: traditional multi-stemmed shrub), applied on unpruned three-year-old plants of the hazelnut cultivar Nocchione, planted in the HD approach (740 plant ha⁻¹). Over five growing seasons (2019–2023), measurements included pruned wood removed, yield, vigor, yield efficiency, nut and kernel traits, and incidence of the main commercial defects. In general, treatment A outperformed other plant-shaping systems, maintaining high yield levels particularly in the two last growing seasons, and showing a mean kernel/nut ratio of 37.7 and a low incidence of defects. Treatment B achieved the highest yield efficiency in 2023 but had lower overall yields. Treatment A demonstrated the most balanced performance, combining high nut quality and stable production, making it the most promising plant training system for HD hazelnut orchards with planting densities above 700 plants per hectare. Future research will assess the long-term adaptability of this plant training system under varying environmental and management conditions. Full article

‘Xinomavro’ (V. vinifera L.) is an important native red wine grape variety in Northern Greece, particularly in PDO (protected designation of origin) regions. Despite its significance, there is limited research on the effects of pruning type and severity on ‘Xinomavro’ vine physiology, yield, and berry quality across diverse environmental conditions. This study aimed to address this knowledge gap and provide growers with crucial information for optimizing vineyard management practices. The study was conducted over two consecutive years (2016 and 2017) in a vineyard in Thessaloniki, Northern Greece. Four treatments (B12: 12 buds on 6 spurs, B24: 24 buds on 12 spurs, M12: 12 buds on 2 canes, and M24: 24 buds on 4 canes) combining two bud load levels (12 or 24 count nodes) and two pruning types (short spurs or long canes) were applied to ‘Xinomavro’ vines in a complete block randomized design. The vine water status, gas exchange, canopy characteristics, yield components, and berry composition were measured. Bud load and pruning type significantly influenced vine canopy development, microclimate, and yield components. Short pruning with high bud load (B24) resulted in denser canopies and higher yields, whereas cane pruning (M12 and M24) led to more open canopies and improved berry quality indicators. Treatment effects on berry composition were inconsistent across years but showed a tendency for higher anthocyanin and total phenol content in cane-pruned vines. This study demonstrates that pruning type (short or long fruiting units) may have a greater impact on vine growth, yield, and berry composition than bud load alone in ‘Xinomavro’ vines. Cane pruning appears to be a more effective strategy for achieving vine balance and potentially improving grape quality under given experimental conditions. Full article

Bud-notching in pear varieties with weak-branches enhances branch development, hormone distribution, and germination, promoting healthier growth and improving early yield. To examine the regulatory mechanisms of endogenous hormones on lateral bud germination in Pyrus spp. (cv. ‘Huangguan’) (Pyrus bretschneideri Rehd.), juvenile buds were collected from 2-year-old pear trees. Then, a comprehensive study, including assessments of endogenous hormones, germination and branching rates, RNA-seq analysis, and gene function analysis in these lateral buds was conducted. The results showed that there was no significant difference in germination rate between the control and bud-notching pear trees, but the long branch rate was significantly increased in bud-notching pear trees compared to the control (p < 0.05). After bud-notching, there was a remarkable increase in IAA and BR levels in the pruned section of shoots, specifically by 141% and 93%, respectively. However, the content of ABA in the lateral buds after bud-notching was not significantly different from the control. Based on RNA-seq analysis, a notable proportion of the differentially expressed genes (DEGs) were linked to the plant hormone signal transduction pathway. Notably, the brassinosteroid signaling pathway seemed to have the closest connection with the branching ability of pear with the related genes encoding BRI1 and CYCD3, which showed significant differences between lateral buds. Finally, the heterologous expression of PyCYCD3 has a positive regulatory effect on the increased Arabidopsis growth and branching numbers. Therefore, the PyCYCD3 was identified as an up-regulated gene that is induced via brassinosteroid (BR) and could act as a conduit, transforming bud-notching cues into proliferative signals, thereby governing lateral branching mechanisms in pear trees. Full article

The aim of this 2022 study was to evaluate the effect of tree growth-limiting treatments on the tree yield and quality of ‘Mutsu’ apples. The experiment was established on 7-year-old trees on M.9 rootstock in a commercial orchard in Wilga near Warsaw. Growth-limiting treatments included unilateral root pruning, spraying the trees with Regalis Plus 10 WG at various times, and spraying with Flordimex 480 SL. Eight combinations were used, with four replicates of 20 trees per repetition. The measurements included fruit set, length of this year’s shoots, yield per tree, average fruit weight, and the size structure of the yield. The distinctive physiological status of the apples was assessed directly after harvest, directly after 8 months of storage under CA conditions (1.5% CO₂, 1.5% O₂, 1 °C, >92% RH) and after an additional 7 days of shelf-life. Spraying trees with Regalis Plus 10 WG from the balloon stage onwards, irrespective of the treatment with root pruning, was most effective in both inhibiting long-stem growth and increasing tree yield (by almost two times) by increasing the number of apples per tree. The growth response of long-stemmed apple trees to both unilateral root pruning and Ethephon spray was significantly lower than it was to Regalis Plus 10 WG spray and had relatively little effect on their yield. Regalis Plus 10 WG resulted in a clear reduction in average fruit weight (by about 100 g), which, in the case of the large-fruited cultivar ‘Mutsu’, should be seen as an advantage. Its application from the balloon stage onwards promoted higher apple firmness at harvest and after simulated handling preceded by long-term storage. Full article

Research into alternative vineyard practices is essential to maintain long-term viticulture sustainability. Organic mulching on the vine row improves vine cultivation properties, such as increasing soil water retention and nutrient availability. This study overviewed the effects of three organic mulches (spent mushroom compost (SMC), straw (STR), and grapevine pruning debris (GPD)) and two conventional soil practices (herbicide application (HERB) and tillage (TILL)) on grapevine physiology, agronomy, and grape quality parameters over three years. SMC mulch enhanced soil moisture and nutrient concentration. However, its mineral composition increased soil electrical conductivity (0.78 dS m⁻¹) and induced grapevine water stress due to osmotic effects without significantly affecting yield plant development. Only minor differences in leaf physiological parameters were observed during the growing season. However, straw (STR) mulch reduced water stress and increased photosynthetic capacity, resulting in higher pruning weights. Organic mulches, particularly SMC and STR, increased grape pH, potassium, malic acid, and tartaric acid levels, while reducing yeast assimilable nitrogen. The effect of organic mulching on grapevine development depends mainly on soil and mulch properties, soil water availability, and environmental conditions. This research highlights the importance of previous soil and organic mulch analysis to detect vineyard requirements and select the most appropriate soil management treatment. Full article

Soil microorganisms play a crucial role in maintaining soil fertility sensu lato. Sustainable soil management aims to make the soil environment more hospitable increasing microorganism diversity and complexity by means of the minimal disturbance of soil and inputs of organic material. This results in the effective functioning of agricultural systems, better crop productivity, and a reduction in environmental impacts. A study was carried out to evaluate the effects of the long-term application (more than 15 years) of sustainable practices versus conventional ones on soil microbial biomass activity and its functional diversity within different Mediterranean commercial fruit orchards located in Southern Italy. A preliminary survey—performed using the electromagnetic induction technique (EMI)—guided the collection of representative soil samples by reducing the spatial heterogeneity of soil microorganisms. Soil management practices, based on no tillage and the recycling of organic materials of different origins and quality produced within the orchard, increased soil organic carbon, telluric microorganisms activity and their functional diversity compared to ‘non-conservative’ management methods such as continuous tillage. In addition, the rational use of the orchard-inside organic matter (natural/seeded grass cover and pruning material) allowed it to virtuously transform from useless waste into precious resources, eliminating the logistical and economic constraints for their disposal. The simultaneous use of different types of soil management strategies aimed at soil conservation reinforced the positive effects on the microbiological indicators of soil quality rather than the application of a single strategy. This study provides the opportunity to represent what could be the possible evolution of tilled orchards towards more balanced soil conditions when subjected to conservative practices, offering a reference model for fruit growers and technicians who want to improve the stability and the resiliency of their agrosystems. Full article

The hedgerow growing system is prevalent in new olive orchards worldwide due to its fully mechanized harvesting. Several works have been published to compare cultivars planted in this system, focusing on productivity and oil composition. However, little research has been conducted on the long-term evaluation of cultivars’ growth habits when trained in hedgerow systems and on how it affects their interannual productivity. In this work, we report the canopy growth habit, productivity, and their correlation for the ‘Arbequina’, ‘Arbosana’, ‘Koroneiki’, ‘Lecciana’, ‘Oliana’, and ‘Sikitita’ cultivars grown in a hedgerow system in Extremadura, central-western Spain, for 9 years. ‘Koroneiki’, ‘Arbequina’, and ‘Lecciana’ were the cultivars with the highest canopy growth, both in young and adult trees, and the ones with the highest pruning needs from 5 to 10 years after planting. The yield behavior in each of the years evaluated was stable in all cultivars except ‘Lecciana’. This alternate bearing was associated with the distribution of total yearly produced biomass between fruits and vegetative growth. ‘Oliana’, ‘Arbosana’, and ‘Sikitita’ were the cultivars with the highest proportion of fruit of the total biomass, and ‘Lecciana’ showed the lowest. This study indicates that cultivars with higher fruit proportions of total biomass might have better suitability for long-term growing in hedgerow formation, fewer pruning needs, and more stable productivity across the years. In this sense, in the climatic conditions considered here, ‘Arbosana’, ‘Sikitita’, and ‘Oliana’ could be the most suitable cultivars for this growing system. Full article

Japanese plums have relatively high water requirements, which depend on supplementing rainfall volumes with accurately quantified irrigation water. There is a lack of knowledge on the seasonal water requirements of plum orchards. This gap in the literature poses an imminent threat to the long-term sustainability of the South African plum industry, which is particularly plagued by climate change and diminishing water resources. The systematic literature review conducted in this study aimed to provide a foundation for supporting water management in irrigated Japanese plum [Prunus salicina Lindl.] orchards. Seventeen peer-reviewed articles obtained from the literature were analyzed. Approximately 66% of the cultivars were cultivated under different regulated deficit irrigation regimes for water-saving purposes and to increase fruit quality. This review of our knowledge provided benchmark figures on the annual water requirements of Japanese plums. The full-year plum crop water requirements obtained from the literature ranged between 921 and 1211 mm a⁻¹. Canopy growth, pruning and growing season length were the most common causes of differences in the water requirement estimates. Further research is required to measure the water requirement of plums from planting to full-bearing age and the response of plum trees to water stress, especially in the South African context. Full article

In recent years, the emergence of large-scale language models, such as ChatGPT, has presented significant challenges to research on knowledge graphs and knowledge-based reasoning. As a result, the direction of research on knowledge reasoning has shifted. Two critical issues in knowledge reasoning research are the algorithm of the model itself and the selection of paths. Most studies utilize LSTM as the path encoder and memory module. However, when processing long sequence data, LSTM models may encounter the problem of long-term dependencies, where memory units of the model may decay gradually with an increase in time steps, leading to forgetting earlier input information. This can result in a decline in the performance of the LSTM model in long sequence data. Additionally, as the data volume and network depth increase, there is a risk of gradient disappearance. This study improved and optimized the LSTM model to effectively address the problems of gradient explosion and gradient disappearance. An attention layer was employed to alleviate the issue of long-term dependencies, and ConvR embedding was used to guide path selection and action pruning in the reinforcement learning inference model. The overall model achieved excellent reasoning results. Full article