Temporal Dynamics of Neonectria ditissima Spore Release From Whole and Shredded Branches of ‘Gala’ and ‘Fuji’ Apple Cultivars Marilia Feliciano Goulart Pereira, Daiana Petry Rufato, Leo Rufato, Ricardo Trezzi Casa, Fábio Nascimento da Silva, et al. Journal of Phytopathology, 2026 European canker (EC), caused by Neonectria ditissima , is one of the major threats to apple production in temperate and subtropical highland regions, where pruning residues represent an important source of inoculum. This study monitored the temporal dynamics of N. ditissima spore release from whole and shredded branches, with and without visible EC symptoms, obtained from training prunings of ‘Gala’ and ‘Fuji’ apple trees during the 2023–2025 growing seasons in high‐altitude orchards of southern Brazil. Whole and shredded branches were placed separately in spore‐trap boxes, and microscope slides were replaced weekly to quantify airborne ascospores and conidia. Shredding was performed using a hydraulic mower. Ascospores were consistently the dominant spore type, exhibiting higher release magnitude and frequency than conidia across all treatments and both cultivars. Whole symptomatic branches were the most productive inoculum source, displaying the highest ascospores and conidia release peaks, particularly in ‘Gala’. Shredding reduced spore output but did not eliminate inoculum viability, as shredded symptomatic branches continued to release substantial quantities of spores throughout the evaluation period. Whole and shredded asymptomatic branches also released ascospores and conidia, although at lower intensities, suggesting the presence of latent infections and confirming that the absence of visible symptoms does not preclude inoculum production. Spore‐release peaks in all treatments occurred during periods with rainfall, highlighting moisture as a key environmental factor for maturation of perithecia and sporodochia and spore discharge. The superior spore release capacity of ‘Gala’ under all conditions indicates that this cultivar may act as a regional inoculum resource in areas where EC is endemic. These findings underscore the need for improved EC management strategies, particularly regarding pruning‐residue handling. The persistence of viable inoculum in symptomatic and asymptomatic tissues, even after shredding, demonstrates that residue destruction or removal is essential to reduce disease pressure and limit pathogen spread within and between orchards.
Plant Growth Regulators on ‘Letícia’ Plum Fruit Set, Yield Performance and Fruit Quality Parameters in Southern Brazil Sabrina Baldissera, Alex Felix Dias, Daiana Petry Rufato, Flávia Lourenço da Silva, André Berner Armbrust, et al. Agriculture Switzerland, 2025 Plant growth regulators (PGRs) such as aminoethoxyvinylglycine (AVG), 1-methylcyclopropene (1-MCP), and thidiazuron (TDZ) are widely used to improve fruit set and quality in stone fruits. This study evaluated the effects of these PGRs on fruit set, yield performance, and fruit quality parameters of the Japanese plum cultivar ‘Leticia’ under the edaphoclimatic conditions of the highland region of southern Brazil during the 2021/22 and 2022/23 growing seasons. The treatments (AVG, MCP, and TDZ) were applied in full bloom in a randomized complete block design with four replications, and the data from both seasons were analyzed by principal component analysis (PCA). All PGRs significantly affected fruit set, yield performance, and fruit quality parameters. The strongest associations were found with 182 mg L−1 TDZ for fruit set, and with 62.5 mg L−1 and 125 mg L−1 AVG, and 21.43 mg L−1 1-MCP for yield performance-related trails. Applications of 125 mg L−1 AVG, 21.43 mg L−1 1-MCP, and 182 mg L−1 TDZ produced fruits with larger diameters and higher fresh weights. The PCA results indicated that TDZ at 182 mg L−1 was closely associated with fruit set and yield performance, suggesting a strong multivariate relationship among these parameters and demonstrating its potential to enhance the productivity of ‘Leticia’ plum under the edaphoclimatic conditions of southern Brazil during the 2021/2022 and 2022/2023 growing seasons.
Cytokinin- and Auxin-Based Plant Growth Regulators Enhance Cell Expansion, Yield Performance, and Fruit Quality in ‘Maxi Gala’ Apple Fruits in Southern Brazil Sabrina Baldissera, Alex Felix Dias, Joel de Castro Ribeiro, Renaldo Borges de Andrade Júnior, Bruno Pirolli, et al. Agriculture Switzerland, 2025 Cytokinin- and Auxin-Based Plant Growth Regulators (PGRs) are commonly employed to increase fruit size due to their ability to modulate cellular structure. This study aimed to evaluate the effects of different PGR application protocols on histological parameters, yield components, and fruit quality in ‘Maxi Gala’ apple. The experiments were carried out under humid subtropical conditions of southern Brazil across two growing seasons (2021/22 and 2022/23), allowing comparison of treatment performance under distinct climatic patterns. Data from common treatments were combined across years for integrated analysis. The PGRs used included 6-benzyladenine (BA) as a cytokinin source; naphthalene acetic acid (NAA) as an auxin source; and tryptophan, a precursor of auxin biosynthesis. PGRs were applied in various combinations and concentrations between 10 days after dormancy break (BBCH 01) and fruit diameters of 25–27 mm (BBCH 74), following a randomized block design with four replicates of twelve trees each. The multivariate analysis of treatments was performed using Principal Component Analysis (PCA). Additionally, an analysis of variance was performed for flesh firmness loss, with means compared using Tukey’s test (p < 0.05). PGRs significantly influenced only the histological parameters of the fruit flesh tissues. BA and tryptophan had the greatest effects on cell size and cell number in the fruit flesh, respectively, both reducing intercellular spaces. Tryptophan was associated with a higher number of smaller cells, whereas NAA promoted larger cell sizes. The combination of BA and NAA, as well as a single application of BA at petal fall, resulted in the highest yield performances and increased the proportion of large fruits. Furthermore, BA enhanced the percentage of red skin coloration and improved flesh firmness during storage.
EPIPHYTIC AND ENDOPHYTIC BACTERIA FOR THE CONTROL OF Botrytis cinerea IN VITRO AND IN GRAPE BERRIES OF CV. SAUVIGNON BLANC IN SOUTHERN BRAZIL Claudemar Helmuth Herpich, Leocir José Welter, Glória Regina Botelho, Fábio Nascimento da Silva, Ricardo Trezzi Casa, et al. Bioscience Journal, 2025 Botrytis bunch rot (BBR) in grapevines caused by Botrytis cinerea is a pre- and post-harvest disease that leads to significant losses in southern Brazil. This study aimed to assess the potential of epiphytic and endophytic bacteria to control B. cinerea in vitro and in vivo in the cv. Sauvignon Blanc (SB). B. cinerea and epiphytic and endophytic bacterial isolates were obtained from the grape clusters and leaf phyllosphere (epiphytic and endophytic) of the SB variety, respectively. Four epiphytic and two endophytic isolates that showed the highest antibiosis indices in vitro and in vivo were identified using phenotyping and DNA sequencing. Treatments were carried out in a completely randomized experimental design with five replications, including (a) control, (b) B. cinerea, (c) commercial product (EcoshotÒ) with Bacillus amyloliquefaciens, (d) epiphytic bacteria, and (e) endophytic bacteria. Among the 52 isolates, 4 epiphytic and 2 endophytic isolates showed the highest degree of inhibition and significantly inhibited the growth of B. cinerea. The UEP40, UEP43, UEN13, and UEN14 isolates yielded positive reactions for urea and indole. The epiphytic isolates UEP43 (identified as Serratia marcescens) and UEP51 (Curtobacterium flaccumfaciens pv. flaccumfaciens) and the endophytic isolate UEN13 (Staphylococcus equorum) reduced the severity of BBR on detached grape berries by ~55% and 49% between 72 and 168 h after inoculation, respectively. These bacterial isolates are potential biocontrol agents against B. cinerea. However, more research is needed to confirm their efficacy in vineyards in southern Brazil.
Cytokinins improve quality of ‘Maxi Gala’ apples produced in southern Brazil Marilia Feliciano Goulart Pereira, Alberto Ramos Luz, Guilherme Fontanella Sander, Augusto Schutz Ferreira, Juliana Fátima Welter Woitexen, et al. Ciencia Rural, 2025 Cytokinins constitute a group of plant growth regulators responsible for a wide range of actions on plant growth and development. This study evaluated the effects of different concentrations and application timings of the cytokinins thidiazuron (TDZ) and benzyladenine (6BA) on fruit cell features, agronomic performance, and the quality of ‘Maxi Gala’ apples produced in southern Brazil over two growing seasons. The experiment comprised seven spray protocols of TDZ and/or 6BA applied at five different phenological stages. TDZ application during the dormant bud stage resulted in yield reduction in the subsequent growing season. TDZ and 6BA influenced fruit cell division and size, respectively, affecting intercellular spaces when applied at the pink bud (PB) and full bloom (FB) stages. The application of 20 mg L-1 of TDZ at the PB and FB stages induced greater fruit cell division with smaller cells size. Application of 10 mg L-1 of 6BA at PB and FB stages increased fruit cell size but reduced intercellular spaces. The application of TDZ or 6BA at PB and FB stages resulted in the lowest losses of fruit pulp firmness during refrigerated storage due to the reduced intercellular space. Among treatments with similar intercellular space, it was observed that a lower number of cells corresponded to a greater reduction in flesh firmness after storage. Treatments with TDZ or 6BA at PB and FB stages; 6BA at PB, FB, fruit 8-12 mm, and fruit 15-20 mm stages; and 6BA at fruit 8-12 mm and fruit 15-20 mm stages exhibited larger cell sizes and quantities, leading to larger fruit sizes but negatively affecting pulp firmness and productivity. Although, the application of TDZ or 6BA at PB and FB stages similarly affected fruit firmness and size. The application of 6BA at PB and FB stages resulted in higher productivity in the ‘Maxi Gala’ cultivar.
Agronomic Performance of European Pear Cultivars in Different Training Systems in the Highland Region of Southern Brazil Alex Felix Dias, S. Baldissera, Alberto Ramos Luz, Augusto Schütz Ferreira, Bruno Dalazen Machado, et al. Agriculture Switzerland, 2025 This study aimed to evaluate the vegetative, productive, and fruit quality parameters of the European pear cultivars ‘Rocha’ and ‘Santa Maria’ under the training systems of Tall Spindle, with branches bent at an angle of 45° (Tall Spindle—45°) and 90° (Tall Spindle—90°) to the leader, and Bi-axis. The evaluation was conducted over the 2016/2017 to 2022/2023 growing seasons in the highland region of southern Brazil. Both Tall Spindle systems significantly improved the yield and productive efficiency compared to the Bi-axis system, with ‘Santa Maria’ showing superior performance under Tall Spindle—90°. While ‘Rocha’ exhibited no significant differences between Tall Spindle systems, it benefited from better vigor control and reduced biennial bearing when trained under the Bi-axis system. Fruit quality parameters were consistent across training systems, indicating Tall Spindle—90° as an optimal choice for productivity and stability in ‘Santa Maria’. These results emphasize the adaptability and efficiency of training systems for pear orchard management.
A novel tenuivirus infecting wheat in Brazil Fernando Sartori Pereira, Lucas Antonio Stempkowski, Thor Vinícius Martins Fajardo, Antonio Nhani Júnior, Douglas Lau, et al. Archives of Virology, 2022
Critical-point models to relate white oat yield and disease intensity of the multiple pathosystem leaf rust - Helminthosporium blight Ciencia Rural, 2010
Red raspberry rust in the state of santa catarina Ricardo Trezzi Casa, Paulo Roberto Kuhnem Junior, Jonatha Marcel Bolzan, Amauri Bogo, Aike Anneliese Kretzschmar, et al. Revista Brasileira De Fruticultura, 2010
Diversity in common bean landraces from south Brazil Acta Botanica Croatica, 2009
