Search Results (111)

Hot water treatment (HWT) is a promising non-chemical method for controlling pests and pathogens in horticultural crops, aligning with the increasing demand for sustainable and residue-free production systems. This study evaluated the effects of various HWT protocols on plant vigour, yield, and fruit weight in strawberry (Fragaria × ananassa) and raspberry (Rubus idaeus) under protected cultivation in Switzerland. Strawberry tray plants were treated at 18–20 °C (ambient), 37 °C, or 47 °C for 10 min prior to planting. Raspberry canes were treated at 18–20 °C, 40 °C, or 45 °C for either 10 or 60 min. In strawberries, no significant differences were observed in the number of flowering stems, flowers, yield per plant, and fruit weight. However, a trend towards lower yields and higher fruit weights has been observed at higher treatment temperatures, particularly 47 °C. In raspberries, bud break was negatively affected by higher temperatures, while leaf area, cumulative yield, and fruit weight remained unchanged across treatments. These results suggest that HWT can be integrated into berry production with minimal impact on plant performance, provided treatment parameters are carefully optimized. Further research is needed to evaluate pest control efficacy under real infestation conditions and to refine protocols for different cultivars and developmental stages. Full article

The increasing volume of plant waste generated by the agro-food industry presents significant environmental and economic challenges. This review synthesizes peer-reviewed literature on the valorization of fruit and vegetable by-products as seed priming agents, focusing on extraction approaches, bioactive compounds, physiological mechanisms, and practical limitations. Seed priming with plant extracts derived from agro-food by-products has emerged as a sustainable approach to enhance seed germination, seedling vigour, and tolerance to abiotic stresses. Recent findings on the composition of bioactive compounds in plant waste, extraction techniques, and the physiological and biochemical effects of these extracts on seeds and seedlings are reviewed. Phenolics, flavonoids, and phytohormones present in these extracts activate antioxidant enzymes and promote secondary metabolite accumulation, mitigating oxidative damage and improving seedling performance. Critical analysis highlights the potential of plant-waste-based extracts for sustainable agriculture and identifies research gaps to optimize their practical application. Full article

This study develops and validates an integrated framework that combines UAV multispectral imagery and canopy structural metrics with gridded climatic variables to predict soybean (Glycine max (L.) Merrill) foliar potassium (K) status and grain yield. Field experiments were conducted over three consecutive growing seasons (2022–2023, 2023–2024, and 2024–2025) under different potassium fertilisation strategies and environmental conditions. Machine learning models, particularly the random forest algorithm, were applied to multisource datasets, including UAV-derived canopy structural traits (height and canopy area), spectral indices (NDVI), meteorological variables, and fertilisation information. The foliar K prediction models achieved high accuracy (R² up to 0.85), while the yield prediction models achieved R² values between 0.71 and 0.81. The inclusion of the potassium rate and fertilisation strategy further improved model performance, highlighting the strong influence of potassium supply and fertilisation management on plant physiological responses. Interestingly, compared with those required to stabilise grain yield, foliar potassium saturation occurred at substantially higher K₂O rates, indicating the occurrence of luxury potassium uptake. The association of UAV-derived canopy metrics with this pattern suggests that remote sensing may help detect subtle nutritional dynamics that are not directly reflected in yield responses. Model interpretability using SHAP analysis identified relationships within the analysed dataset that were consistent with physiological expectations, with positive contributions associated with canopy vigour and negative contributions associated with thermal stress. In addition, probabilistic SHAP analysis provided a decision-oriented perspective by quantifying yield probabilities under contrasting potassium management regimes and climate scenarios. Overall, within the experimental conditions studied, the proposed framework enabled a rapid assessment of crop nutritional status, yield prediction, and the evaluation of fertilisation strategies. The integration of UAV data, climatic variables, and machine learning provides an interpretable basis for potassium management and soybean yield forecasting within the experimental conditions studied, while broader transferability requires external validation. Full article

The response of five Passiflora species as rootstocks for yellow passion fruit was evaluated against the Meloidogyne incognita complex and Fusarium oxysporum f. sp. passiflorae. Individual, sequential, and simultaneous inoculations were applied, quantifying disease severity, nematode reproduction (RF), biomass, and plant vigour. In addition, integrated analysis was performed using the Combined Tolerance Index (CTI) to confirm the simultaneous interaction of the inoculation condition. The graft compatibility index (GCI) of the materials under study was also determined. The results showed critical functional differences; P. maliformis showed tolerance in terms of compensatory vigour but presented high susceptibility to the nematode and low graft affinity (GCI = 1.39). In contrast, P. platyloba emerged as the superior genotype, combining effective resistance to Meloidogyne (zero incidence at critical stages), excellent anatomical compatibility (deviation from the ideal of 0.04), and physiological stability superior to the control. Although P. nitida showed resilience in biomass under severe stress conditions, it is concluded that P. platyloba is the most promising alternative for use as rootstock. This is because its morphological affinity and health resistance ensure crop sustainability in field conditions and promote more sustainable agricultural practices. Full article

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

Sorghum is a resilient crop important for sustainable intensification in semi-arid regions, yet the impact of variable seeding rates on its early development remains under-researched. This research investigated the early establishment of hybrid sorghum under three seeding strategies, ”Uniformise” (medium density across all zones), “Optimise” (increased density in low-soil apparent Electrical Conductivity (ECa)), and “Maximise” (increased density in high-soil ECa), at the Herdade da Comenda (Innovation Center—Elvas, Portugal). Crop performance was monitored over 33 days, the established window for safe direct grazing, using Unmanned Aerial Vehicle (UAV) multispectral imagery to derive the Normalised Difference Vegetation Index (NDVI) and Canopy Cover (Cveg), alongside physical sampling of plant height and biomass. Statistical analysis revealed that both the seeding strategy and soil variability significantly affected early growth. The “Uniformise” strategy recorded the highest plant height, NDVI, and Cveg values, whereas the “Optimise” strategy performed the poorest. Additionally, an accumulation of 407.5 Growing Degree-Days (GDDs; °C) accelerated the phenological cycle by five days relative to the climatological normal. Despite differences in vegetative vigour, no statistically significant variations were observed in final biomass across the strategies. These results indicate that while the “Uniformise” approach provided a more balanced environment for early establishment under these specific Mediterranean conditions, the lack of biomass differentiation highlights the potential for resource optimisation. The study demonstrates that UAV-based remote sensing is a useful diagnostic tool to identify these spatial limitations, providing the data to refine variable-rate seeding (VRS) algorithms and improve the economic efficiency of precision sowing. Full article

Callogenesis is a fundamental step in plant biotechnology and tissue culture, providing the basis for multiple scientific and practical applications. In this study, the impact on callogenesis of different plant growth regulators was studied on Cannabis sativa L. (a non-commercial genotype of hemp), with the objective of identifying the most suitable combination for the establishment of vigorously growing, friable calli. Forty-nine media combinations were evaluated using four PGRs: two auxins (2,4-dichlorophenoxyacetic acid, naphthaleneacetic acid) and two cytokinins (6-benzylaminopurine, kinetin). Parameters such as percentage of callus induction, proliferation, colour, texture, and growth area were assessed. Three media were identified for further spectrophotometric assays and targeted gene expression analysis: the first containing 2,4-dichlorophenoxyacetic acid 1.5 µM and benzylaminopurine 1.5 µM, the second with 2,4-dichlorophenoxyacetic acid 1.5 µM and kinetin 1.5 µM and the third supplemented with 2,4-dichlorophenoxyacetic acid 4.5 µM and kinetin 1.5 µM. The last medium proved to be superior in terms of vigour, friability and phenolic content and showed increased expression of genes involved in the early steps of the phenylpropanoid pathway. These findings highlight the central role of auxin–cytokinin interactions in regulating both callus formation and secondary metabolism. The optimised medium opens the way to subsequent biotechnological applications relying on the cultivation of plant cell suspension cultures. Full article

Modern olive breeding points to a plant model characterized by low vigour, high productivity, and resistance to biotic and abiotic stresses, all traits required by the intensive and superhigh-density (SHD) systems of olive tree growing. The Italian Don Carlo and FS-17 Favolosa stand out among the new cultivars that are being tested. They were obtained not by breeding but by mass selection from two seedling populations of the Frantoio cultivar (maternal parent). Here, a multidisciplinary approach was used to determine the paternal parent of Don Carlo and FS-17, and then to investigate the inheritance of interesting traits such as fruit cell dimensions and oil content in these cultivars. Microsatellites were applied in phylogeny and kinship analyses, along with two functional markers previously developed on OeACP1 and OeACP2 genes. Ascolana Tenera cultivar was identified as the paternal parent of both new cultivars. This result was also supported by the analysis of the self-incompatibility group of the new cultivars and their most likely paternal parents. Light and electron microscopy [Cryo Scanning Electronic Microscopy (CRYO-SEM), Electronic Scanning Microscopy (E-SEM), and Transmission Electron Microscope (TEM)] techniques were used to analyze the fruit development concerning oil accumulation. Significant differences in cuticle thickness, size and shape of mesocarp and exocarp cells, and oil content were detected among cultivars. Our results suggested that the rearrangement of the traits studied led to an improved progeny compared to the parents. FS-17 exhibited an oil storage efficiency higher than Frantoio. Don Carlo showed fruit traits and oil content almost intermediate between the parents, making it a dual-purpose cultivar. Full article

Growers rarely use the grafting method on a double-root system due to limited information on the added advantages for increased plant vigour and yield of soilless-grown cucumber (Cucumis sativus L.). The study aimed to investigate the effect of combining rootstock cultivar and the grafting method on the growth, yield, and quality of soilless-grown cucumber in a non-temperature-controlled (NTC) tunnel. Two rootstock cultivars, Flexifort (Flex) (Cucurbita maxima × Cucurbita moschata) and Ferro (Fer) (C. maxima × C. moschata), were grafted with scion cultivar Hoplita (H) to either single- (1R) or double- (2R) root systems, and the original scion root system was combined with either a Flexifort or Ferro rootstock (O1R) to two root systems and a non-grafted plant (Hoplita). Plants were grown in 10 L containers filled with sawdust as a growing medium. The leaf number was higher in ‘HO1RFlex’ combinations, while the non-grafted plants had a significantly lower leaf number. Thicker stem diameter was obtained from non-grafted plants. The tallest plants were obtained from HO1Fer combinations at 39, 53, and 101 days after transplanting (DAT), while non-grafted plants at 25 and 101 DAT were the shortest plants. Plants grafted to single- or double-root systems, regardless of rootstock cultivar, had higher early, marketable, and total yield compared to non-grafted cucumber. Many medium-sized fruits were obtained in ‘HO1RFlex’ combinations during the early harvest. The total soluble solids (TSSs) of cucumber juice were higher in ‘H1RFer’ while fruit mineral content was not affected by the combined rootstock cultivar and grafting method. Grafting to a double-root system using the original scion roots combined with rootstock or double rootstock had a limited effect compared to plants grafted to a single-root system. It is recommended that scion be grafted to a single-root system of either rootstock Ferro or Flexifort compared to a double-root system, particularly for the cost effectiveness of seeds and labour used in grafting, as well as for improved vegetative growth, including early marketable and total yield of cucumber. The growing containers of various sizes need further investigation to allow for the root extension and growth of grafted plants. Full article

The improvement of Lavandula angustifolia Mill. seed germination represents a crucial step towards the development of eco-biotechnological solutions for the sustainable propagation of aromatic plants. This study evaluated the effects of four biostimulant formulations, namely Amino 16 (amino acid-based), Razormin (humic–fulvic complex), Germinoseed (phytoextract-based), and Atonik (nitrophenolate), together with a non-treated control, on the germination efficiency and early growth of nine Lavandula genotypes under controlled laboratory conditions. A factorial design (9 × 5) with four replications was applied, and multiple germination indices were calculated. Data were analysed using a two-way ANOVA with genotype and treatment as main factors. Results indicated significant genotype-dependent responses. Amino 16 and Razormin markedly increased germination percentage, speed of emergence, and seedling vigour, achieving up to 100% germination in responsive genotypes such as ‘Ellagance Snow’ and ‘Blue Spear’. Correlation and clustering analyses revealed strong links between seed size, germination rate, and seedling development, suggesting a possible synergistic role of amino and humic substances in stimulating metabolic activation during germination. These findings demonstrate that eco-friendly biostimulants function as effective biotechnological activators of seed physiology, supporting low-input propagation systems and the transition toward a circular green bioeconomy. Full article

Seed-related traits such as seed size, germination, vigour, dormancy, biochemical composition, and stress resistance are critical to ensuring agricultural productivity and global food security, particularly in current scenarios of climate change and environmental unpredictability. This review examines the transformative potential of omics technologies, encompassing genomics, transcriptomics, proteomics, metabolomics, epigenomics, and phenomics, in enhancing our understanding of seed biology and its applications in crop improvement. Genomics and transcriptomics are key technologies in future plant breeding and gene editing to optimise seed yield and quality. We reviewed the role of metabolomic approaches in uncovering the molecular mechanisms behind seed germination, vigour, dormancy, and the proteomic advances to elucidate markers of seed quality, combining these omic technologies to decipher DOG1 as a marker of dormancy. Both biotic and abiotic stress resistance in seeds were reviewed from a multi-omics perspective to determine the best avenues for improving the resilience of seeds against drought, salinity and pathogens. Moreover, omics approaches have been reviewed to optimise plant–microbe interactions, particularly in enhancing symbiotic relationships within the soil microbiome. Full article

Understanding the impact of hydric stress on medicinal plants in the context of climate change is becoming increasingly important. This study aimed to assess the quality of a seed lot of Agastache mexicana subsp. mexicana (Amm) through a novel calculation of the Vigour Index on time basis (${VI}_T$). The evaluation was based on relationships among plant height, leaf number, survival time, and plant density across six irrigation regimes, referred to as stages, which differed in the timing and quantity of water, designed to impose water stress from seedling emergence until plant death. To maximise growth and survival time, we utilised two input factors: Artificial Shade Levels (ASLs) of 38%, 87%, and 94%, as well as Silicon Dioxide Levels (SDLs) of 0.0%, 0.2%, 0.4%, and 0.8%. The effects of these treatments were measured using the Survival Index (SI) and the ${VI}_T$. The plants achieved their highest SI and ${VI}_T$ values influenced by minimum mortality and maximum height and leaf number in stage three. This behaviour aligned with the field capacity of the substrate, supporting the evaluation of stages one and two as waterlogging stress, while the remaining stages were classified as drought stress. The ${VI}_T$ results showed statistically significant effects from ASL, particularly at 94%. However, the ${VI}_T$ in relation to SDL was not statistically significant. The ${VI}_T$ measurements were visualised using spline interpolation, a method that provides an effective approach to quantify adverse conditions affecting Amm’s development and that it can support to identify the hydric stresses type. Full article

Advances in Earth observation technology using multispectral imagery from satellite Earth observation systems and sensors mounted on unmanned aerial vehicles (UAVs) are enabling more accurate crop monitoring. These images, once processed, facilitate the analysis of crop health by enabling the study of crop vigour, the calculation of biomass indices, and the continuous temporal monitoring using vegetation indices (VIs). These indicators allow for the identification of diseases, pests, or water stress, among others. This study compares images acquired with the Altum PT sensor (UAV) and Super Dove (satellite) to evaluate their ability to detect specific problems in super-intensive olive groves at two critical times: January, during pruning, and April, at the beginning of fruit development. Four different VIs were used, and multispectral maps were generated for each: the Normalized Difference Vegetation Index (NDVI), the Green Normalized Difference Vegetation Index (GNDVI), the Normalized Difference Red Edge Index (NDRE) and the Leaf Chlorophyll Index (LCI). Data for each plant (n = 11,104) were obtained for analysis across all dates and sensors. A combined methodology (Spearman’s correlation coefficient, Student’s t-test and decision trees) was used to validate the behaviour of the variables and propose predictive models. The results showed significant differences between the sensors, with a common trend in spatial patterns and a correlation range between 0.45 and 0.68. Integrating both technologies enables multiscale assessment, optimizing agronomic management and supporting more sustainable precision agriculture. Full article

Despite the extensive cultivation of Moringa trees in tropical regions, understanding of accession-specific performance across diverse agroecological zones remains inadequate. Thus, this study evaluated the growth, adaptability, and leaf yield performance of 12 Moringa accessions (11 M. oleifera and 1 M. stenopetala) over three years in a subtropical climate (Pretoria, South Africa). Seeds were planted in seedling trays in the glasshouse at the University of Pretoria’s experimental farm. Vigorous seedlings were transplanted to the field at the Roodeplaat experimental site of the Agricultural Research Council two months after establishment, following a randomized complete block design (RCBD). Data were measured on establishment (emergence, survival), growth and yield parameters, and monitored plant health via leaf greenness, vigour, chlorosis, and pest and disease incidence. Accessions exhibited substantial variation for most traits, except for stem diameter. Moringa stenopetala showed the highest initial emergence rate but later displayed lower survival rates than most M. oleifera accessions. Survival rates, morphological features (plant height, canopy diameter, and branching), visual scores for leaf greenness and plant vigour, and leaf yield (fresh and dry) varied considerably among the accessions. Moringa oleifera A2 consistently performed well, exhibiting vigorous growth, the maximum survival rate (78%), and fresh leaf production (6206 kg ha⁻¹). Accessions A3 and A8 showed intermediate yield and longevity, indicating potential for cultivation or breeding. Conversely, M. oleifera A10 and M. stenopetala markedly underperformed in most traits, limiting their cultivation potential. Based on multi-year performance, A2 is suggested for large-scale cultivation due to its vigour, yield, and stress tolerance, while A3 and A8 hold breeding potential. The study emphasizes the critical role of genetic variation and selection in enhancing Moringa productivity under subtropical environments. Future work should focus on genetic characterization and agronomic practices optimization of superior accessions. Full article

The rapid and reliable acquisition of canopy-related metrics is essential for improving decision support in viticultural management, particularly when monitoring individual vines for targeted interventions. This study presents a spatially explicit workflow that integrates Uncrewed Aerial System (UAS) imagery, 3D point-cloud analysis, and Object-Based Image Analysis (OBIA) to detect and monitor individual grapevines throughout the growing season. Vines are identified directly from 3D point clouds without the need for prior training data or predefined row structures, achieving a mean Euclidean distance of 10.7 cm to the reference points. The OBIA framework segments vine vegetation based on spectral and geometric features without requiring pre-clipping or manual masking. All non-vine elements—including soil, grass, and infrastructure—are automatically excluded, and detailed canopy masks are created for each plant. Vegetation indices are computed exclusively from vine canopy objects, ensuring that soil signals and internal canopy gaps do not bias the results. This enables accurate per-vine assessment of vigour. NDRE values were calculated at three phenological stages—flowering, veraison, and harvest—and analyzed using Local Indicators of Spatial Association (LISA) to detect spatial clusters and outliers. In contrast to value-based clustering methods, LISA accounts for spatial continuity and neighborhood effects, allowing the detection of stable low-vigour zones, expanding high-vigour clusters, and early identification of isolated stressed vines. A strong correlation (R² = 0.73) between per-vine NDRE values and actual yield demonstrates that NDRE-derived vigour reliably reflects vine productivity. The method provides a transferable, data-driven framework for site-specific vineyard management, enabling timely interventions at the individual plant level before stress propagates spatially. Full article