Search Results (99)

Raspberry (Rubus idaeus L.) micropropagation is an alternative for obtaining plantlets with high genetic and phytosanitary quality. The objective of this study was to establish a protocol for the micropropagation of raspberry (Rubus idaeus L.) using the temporary immersion bioreactor, under intermittent immersion periods and different culture medium volumes. The effect of the liquid medium using the TIB and semisolid was evaluated. Different immersion frequencies and culture medium volumes per explant were evaluated in the TIB. In all treatments, the number of shoots per explant, shoot length, number of leaves per explant, percentage of hyperhydricity, and chlorophyll and β-carotene content at multiplication stage were evaluated. The generated shoots, without a root system, were transferred to the acclimatization stage. The results show that the TIB with an immersion frequency of 2 min every 8 h and a volume of 25 mL of culture medium per explant had the best developmental parameters, with 5.75 shoots per explant, a shoot length of 3.44 cm, and 2% hyperhydricity. The highest chlorophyll and β-carotene content was observed in the TIB at different immersion frequencies of 4, 8 and 12 h, with 25 and 50 mL per explant. Survival percentages higher than 96% were observed in all methods evaluated. In conclusion, the evaluated immersion system is an efficient alternative for R. idaeus micropropagation, without using a rooting stage. Full article

Downy mildew, caused by Plasmopara viticola, is a major threat to grapevine (Vitis vinifera) cultivation in humid climates. Restrictions on synthetic pesticides and inconsistent efficacy of current biocontrol agents, especially under rainy conditions, complicate disease management. This study evaluated the potential of compost tea to suppress downy mildew in a two-year field experiment (2023 and 2024), combined with reduced synthetic fungicide applications. The study design compared two phytosanitary management strategies on a commercial vineyard: a conventional fungicide against a compost tea strategy supplemented with two cymoxanil applications. The experiment set up had three replicated blocks, each consisting of 100 plants for a total of 600 plants. Mechanistic insights were provided through controlled laboratory experiments involving pre- and post-infection leaf assays, vineyard bacteriome profiling, via 16S rRNA gene sequencing for bacterial communities, across vineyard compartments, i.e., bulk soil, rhizosphere, and phyllosphere, and grapevine metabolomic analysis by GC-MS analysis. Field trials demonstrated that compost tea combined with two fungicide applications effectively reduced disease severity, notably outperforming the fungicide alone in the particularly rainy year of 2023. Bacteriome analysis revealed that compost tea treatment enriched beneficial bacterial genera, including Pseudomonas, Sphingomonas, Enterobacter, Massilia, and Bacillus, known for their growth-promoting and biocontrol activity in the rhizosphere and phyllosphere. Laboratory assays on detached leaves further showed that compost tea alone could suppress both infection and sporulation of P. viticola. Metabolomic analysis highlighted the accumulation of compounds such as tartaric and shikimic acids in compost tea treated leaves, suggesting a potential role in induced resistance. The findings indicate that applying compost tea with reduced fungicide treatments represents a promising and sustainable strategy for managing grapevine downy mildew, even in challenging climates. Full article

The oriental fruit fly (B. dorsalis) poses a critical threat to domestic mandarin trade, necessitating effective phytosanitary measures. This study evaluated ethyl formate (EF) and phosphine (PH₃) fumigation as alternative disinfestation methods, either alone or in combination with cold treatment, using B. scutellata, pumpkin fruit fly, as a surrogate species. Eggs and third-instar larvae were tested under both naked and inoculated conditions. Results indicated that larvae were more susceptible to treatment than eggs. The LT_99% values for cold treatment (1.7 °C) were 8.6 and 12.4 days under naked and inoculated conditions, respectively. EF LCt_99% values were 265.7 and 1111.0 g h/m³. EF (LCt_50%) combined with PH₃ (1.0 g/m³) achieved up to 100% mortality, while EF (LCt_50%) followed by cold treatment (1.7 °C for 1–3 days) significantly enhanced mortality compared to cold treatment alone. This study offers foundational data to optimize EF-based quarantine treatments against B. dorsalis, supporting shorter treatment times and more cost-effective quarantine practices. Future studies should validate these findings under practical field conditions. Full article

Drosophila suzukii, classified as a quarantine pest in some countries, poses a serious threat to global trade due to its ability to damage berries and cherries. Recent studies indicate that low-temperature phosphine (PH₃) fumigation effectively controls this pest without compromising fresh produce quality. However, the specific protocol for managing D. suzukii larvae in cherries using this method remains underexplored. This study evaluates the efficacy of low-temperature PH₃ fumigation in controlling D. suzukii larvae across three cherry varieties at 3 °C and investigates potential effects on key quality metrics. Tolerance assessments revealed that 3rd instar larvae exhibit the highest resistance to PH₃ among all developmental stages. A concentration of 800 mL/m³ PH₃ for 84 h at 3 °C achieved phytosanitary efficacy for 0.99997 with no negative effect on the quality attributes of the tested cherry varieties. These results support low-temperature PH₃ fumigation as a viable postharvest treatment for D. suzukii management in sweet cherries. Full article

Evaluating cultivar susceptibility to biotic stressors in apple orchards is essential for selecting genotypes adapted to local conditions and for designing effective plant protection strategies. This study conducted a comparative assessment of five apple cultivars (‘Florina’, ‘Jonathan’, ‘Golden Delicious’, ‘Pinova’, and ‘Idared’) in response to major fungal diseases (Venturia inaequalis, Podosphaera leucotricha, and Monilinia spp.) and insect pests (Eriosoma lanigerum, Quadraspidiotus perniciosus, Anthonomus pomorum, Aphis spp., and Cydia pomonella). The cultivars were monitored over a five-year period in six orchards located in Central Transylvania, Romania. Significant differences in phytosanitary behavior were recorded among cultivars and locations. ‘Florina’ consistently showed the highest tolerance to pathogens and pests across all sites and years, while ‘Jonathan’ and ‘Golden Delicious’ proved highly susceptible, particularly to apple scab, powdery mildew, aphids, and codling moth. Pest incidence was strongly influenced by temperature, while disease occurrence was more closely linked to precipitation patterns. Heritability analysis indicated that genetic factors played a substantial role in shaping cultivar responses to most biotic stressors. The integrated approach to cultivar–location–pathogen and pest interactions offers practical insights for optimizing orchard protection strategies under variable ecological conditions. Full article

Monitoring vineyard diseases such as downy mildew (Plasmopara viticola) is important for viticulture, enabling an early intervention and optimized disease management. This is crucial for disease monitoring, and the use of high-spatial-resolution multispectral data from unmanned aerial vehicles (UAVs) can allow to for a better understanding of disease progression. This study explores the application of UAV-based multispectral data for monitoring downy mildew infection in vineyards through multi-temporal analysis. This study was conducted in a vineyard plot in the Vinho Verde region (Portugal), where 84 grapevines were monitored, half of which received phytosanitary treatments while the other half were left untreated in this way during the growing season. Seven UAV flights were performed across different phenological stages to assess the effects of infection using spectral bands, vegetation indices, and morphometric parameters. The results indicate that downy mildew affects canopy area, height, and volume, restricting the vegetative growth. Spectral analysis reveals that infected grapevines show increased reflectance in the visible and red-edge bands and a progressive decline in near-infrared (NIR) reflectance. Several vegetation indices demonstrated a suitable response to the infection, with some of them being capable of detecting early-stage symptoms, while vegetation indices using red edge and NIR allowed us to track disease progression. These results highlight the potential of UAV-based multi-temporal remote sensing as a tool for vineyard disease monitoring, supporting precision viticulture and the assessment of phytosanitary treatment effectiveness. Full article

Tephritid fruit flies are serious pests of Ghana’s numerous economically important fruits and vegetables. Their damages include rotting, premature ripening, and dropping of fruits, which lead to severe production losses, reduction in export volumes, trade restrictions, and other health implications when infested fruits are consumed. Due to the activities of these pests, less than 10% of fruits (especially mango) and vegetables produced are exported, and more than 60% of them end up in waste yearly. With current regulatory measures, Ghana has made significant progress in managing fruit flies, especially after the European Union (EU) ban in 2015. However, the pests remain problematic in the sub-region. A more coordinated nationwide approach and investments in postharvest treatment facilities are anticipated to help reduce pest populations, increase trading volumes and incomes, increase access to other markets, including the United States, and boost Ghana’s economy. It is estimated that for every US$1 invested in managing fruit flies, the return on investment is US$93. Full article

The root system of clonal rootstocks has been poorly studied, despite its crucial importance. Roots not only provide support and nutrition to the plant but also contribute to tolerance to pests, diseases and environmental stresses, in addition to optimizing yields. Although the initial cost of clonal rootstocks is higher, the investment is offset by the reduction in phytosanitary treatments, greater longevity of the trees and a lower mortality rate. The aim of this research was to quantify the root system growth of five clonally propagated dwarf and normal avocado genotypes evaluated in rhizotrons, with the perspective of identifying distinctive characteristics suitable for their possible use in container culture. The avocado clonal plants to be evaluated were placed in rhizotrons and evaluated for six months, where 35 growth variables were evaluated with the aid of a root analyzer program. A randomized complete block design with five treatments (genotypes) and three replications was used under greenhouse conditions. Analysis of variance, variable purge and multivariate analysis were performed. It was found that ‘Duke 7’ and ‘San Martín’ were statistically different for most of variables, with ‘San Martín’ showing less root growth and ‘Duke 7’ showing remarkable lateral growth. The adventitious root system’s growth depends on the genotype, and the use of rhizotrons allows its study, which proved to be a useful methodology for this type of evaluation since it allows the visualization and adequate quantification of root growth. Genotypes with less root growth may be suitable for use in container culture, and roots with extensive lateral growth may be useful in shallow soils. Full article

Corn (Zea mays L.) productivity is often compromised by phytosanitary challenges, with fungal disease like Curvularia leaf spot being particularly significant. While synthetic fungicides are commonly used, there is growing interest in exploring alternative compounds that are effective against pathogens, ensure food safety, and have low toxicity to non-target organisms. In this study, we examined the biochemical changes in corn plants treated with Lippia sidoides essential oil and its major compound, thymol. Both treatments serve as preventive measures for inoculated plants and induced resistance. We tested five concentrations of each product in in vivo experiments. After evaluating the area under the disease progress curve, we analyzed leaf samples for enzymatic activities, including superoxide dismutase, catalase, ascorbate peroxidase, and chitinase. Phytoalexin induction was assessed using soybean cotyledons and sorghum mesocotyls. Cytotoxicity tests revealed lower toxicity at concentrations below 50 µL/mL. Both essential oil and thymol stimulated the production of reactive oxygen species, with thymol primarily activating catalase and L. sidoides oil increasing ascorbate peroxidase levels. Both thymol and L. sidoides were also key activators of chitinase. These findings suggest that L. sidoides essential oil and thymol are promising candidates for developing biological control products to enhance plant defense against pathogens. Full article

Hyadaphis foeniculi is a significant phytosanitary issue in fennel (Foeniculum vulgare) cultivation, necessitating rational management strategies, such as biological control using entomopathogenic fungi and natural predators. This research aimed to assess the virulence parameters of the entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae, isolated or in mixture, in the mortality of H. foeniculi, and investigate the compatibility of these fungi with the predator Euborellia annulipes, analyzing the functional response when preying-on-aphids. The experiment was conducted under laboratory conditions. The lethal concentrations (LC50 and LC90), the median lethal time (LT50), and the percentage of survival of H. foeniculi nymphs subjected to topical application of the fungi were evaluated. No significant difference existed between the lethal concentrations and LT50 of the fungi alone or combined, with LC50 estimated at 1.17 × 10⁶ conidia of B. bassiana per milliliter of water suspension and 1.20 × 10⁶ conidia of M. anisopliae per milliliter of water suspension, when isolated. When in mixture, we observed LC50 for the mixture of fungi M. anisopliae and B. bassiana estimated at 3.06 × 10³ viable conidia of B. bassiana, and 1.17 × 10³ viable conidia of M. anisopliae per mL of distilled water. Therefore, the mixture of fungi showed remarkable promise, resulting in a high aphid mortality rate. Adult females of E. annulipes were used to evaluate the compatibility of the fungi with this predator and were exposed to the fungi to assess its functional response to nymphs of fennel aphid. The fungi had no significant effect on the functional response parameters of the females exposed to the treatments. Thus, the two bioagents (predator and fungi) proved compatible and promising for fennel aphid biological control programs. Full article

Current crop management worldwide is shifting toward the use of environmentally friendly products. With this objective, we developed a new phytosanitary product with biostimulant properties based on the encapsulation of garlic extract at a lower dose (<0.1%) in chitosan nanoparticles as a seed nano-priming agent. In the present study, the morphology of the nanoparticles, their stability under prolonged storage conditions, and their efficacy as a biostimulant are evaluated on cereals in rainfed crops, and the activities were correlated with a transcriptomic analysis. The nanoparticles showed a spherical shape and had a maximum size close to 200 nm with satisfactory stability at 4 °C, reducing the probability of aggregation processes in the nanoparticles. The biostimulant properties of the nano-priming agent were evaluated in a field experiment with wheat, barley, and oat seeds at 30 and 90 days, showing that plants treated with nanoparticles showed significant differences with higher values in root development, leaf length, and total plant weight. Finally, through a RNA-SEQ analysis of the treated wheat seeds, we have confirmed that the nano-treatment showed a higher increases in regard to development, metabolism, and plant response genes compared with untreated seeds. Full article

Oulema melanopus L., 1758 (Coleoptera: Chrysomelidae) is one of the significant pests affecting cereal crops in Europe. Its damage is evident in the destruction of leaves during the spring growing season, leading to substantial impacts on both the quantity and quality of the harvested yields. The study aimed to evaluate the extent of leaf surface damage, changes in chlorophyll content caused by this pest, and the subsequent effects on yield quality. To achieve this, two experimental parcels were established, each subjected to different pesticide treatments during the spring vegetation cycle, but notably, with the difference that one parcel did not receive insecticide applications. The phytosanitary status, yield quantity, and quality parameters of thes parcels were compared. Chlorophyll content in damaged and undamaged plants was monitored in vivo using SPAD measurements, while the extent of leaf surface damage was assessed through image analysis using GIMP software 2.10.32. Harvested grain underwent milling and baking analysis, with milling and baking-quality indicators measured using a NIR grain analyzer. The results revealed that omitting springtime insecticide treatments during the emergence of O. melanopus led to significant reductions in leaf area and yield quality. In untreated parcels, leaf decession followed linear progression, reaching 35–40% within 20 days. This damage correlated with the decline in SPAD index values, indicating a 40–50% reduction in chlorophyll content dependent photosynthetic activity. Consequently, there were substantial decreases in milling and baking qualities, including nearly 30% reductional protein-content indicators and 10% in the Hagberg falling number. In summary, our large-scale field experiments demonstrated that persistent O. melanopus damage in wheat fields significantly reduced both the quantity and quality of yields, particularly protein content. These facts underscore the economic importance of timely pest-control measures to mitigate damage and preserve crop value. Full article

Apple scab, caused by Venturia inaequalis, is one of the most important diseases in apples in all production regions and its sustainable control is still a challenge. The aim of this work was to optimize the control of apple scab through different environmentally friendly inoculum management strategies, specifically the removal of fallen leaves in winter and the treatment of ground leaves with the biological agent Trichoderma asperellum (T34 BIOCONTROL^®) to inhibit or prevent inoculum development in commercial orchards. The results obtained from 4 years of trials in commercial orchards demonstrated that the combination of fungicide treatments and leaf litter management, particularly through aspiration, significantly reduced the development of apple scab in comparison with strategies commonly used by growers that are based solely on fungicide application. Both the incidence and severity of the disease in leaves and fruit decreased by over 90% when inoculum management and fungicide treatments were combined. These results highlight that reducing the source of inoculum by removing fallen leaves is an effective strategy that complements fungicide or biological control agent applications. In conclusion, combining eco-friendly strategies with standard fungicides and monitoring environmental conditions can help to reduce the frequency of phytosanitary applications, ultimately contributing to the goal of minimizing their use in the control of apple scab. Full article

Although phytosanitary treatments are necessary to protect grapes from parasitic diseases, consumers are increasingly concerned about the use of synthetic phytosanitary products and their possible residues in wine. Pre-harvest phytosanitary treatments are often inevitable, and consequently downtime is required to avoid possible residues on the grapes. Instead, natural phytosanitary products, such as essential oil (EO)-based products, can be applied close to the harvest without specific restrictions, with results that are not only technically convenient but also more attractive for the consumers. Because of the high antimicrobial activity of EO products, in the present study we evaluated the effect of different residual amounts of two new EO-based phytosanitary products on the alcoholic fermentation and the chemical composition of the final fermented products. In particular, two EO-based new formulations, exploitable in organic viticulture management, were evaluated. Increasing concentrations of each formulation were tested during laboratory scale fermentations and in comparison with synthetic and natural commercial phytosanitary products. Growth and fermentation kinetics of a commercial yeast strain of Saccharomyces cerevisiae and the chemical and sensory profiles of the final products were evaluated. Both new formulations showed no significant impact on the growth and fermentation kinetic of S. cerevisiae at any of the concentrations tested. In all trials, alcoholic fermentation was completed in 15 days. Instead, a different chemical composition of the final products was observed. Therefore, these new products might represent an interesting alternative tool to the conventional phytosanitary treatments, being applicable close to the harvest without negative impacts on the kinetics of alcoholic fermentation and also being more acceptable to wine consumers. Full article

The application of biological pesticides as alternatives to chemical phytosanitary products is a natural and innovative method to improve environmental protection and sustainable agricultural production. In this work, the compatibility between Trichoderma spp. and a commercial lignin extract was assessed in vitro and in vivo. The beneficial effects of lignin in combination with different Trichoderma consortia were evaluated in terms of improved growth and quantitative and qualitative tomato productivity. T. virens GV41 + T. asperellum + T. atroviride + lignin formulation was the most effective in growth promotion and increased root and stem dry weight compared to control (45.4 and 43.9%, respectively). This combination determined a 63% increase in tomato yield compared to the control, resulting in the best-performing treatment compared to each individual constituent. Consistent differences in terms of lycopene, GABA, ornithine, total, essential, and branched-chain amino acids were revealed in fruits from tomato plants treated with Trichoderma–lignin formulations (T. asperellum + T. virens GV41 + lignin) or with the microbial consortia (T. asperellum + T. virens GV41, T. atroviride + T. virens GV41). The developed bioformulations represent a sustainable biological strategy to increase yield and produce nutritional compound-enriched vegetables. Full article