https://www.alice.cnptia.embrapa.br/alice/handle/item/17 Embrapa Hortaliças (CNPH) Sun, 09 Aug 2026 17:28:29 GMT 2026-08-09T17:28:29Z https://www.alice.cnptia.embrapa.br/alice/handle/doc/1189007 Título: Xanthomonas euvesicatoria associated with outbreaks of bacterial blight of onion in Central Brazil. Autoria: FERREIRA, L. da C.; ALVES, A. R.; MACEDO, W. da S.; ROSSATO, M; OLIVEIRA, V. R.; QUEZADO-DUVAL, A. M. Conteúdo: Since 2018, outbreaks of typical bacterial blight caused by Xanthomonas have been observed in summer onion crops in central Brazil. To identify the Xanthomonas species involved and evaluate the role of rotation crops (e.g., soybean) and weeds, surveys were conducted at outbreak sites from 2018 to 2021. Forty-two xanthomonad-like isolates were obtained from symptomatic leaves (33 from onion, four from Euphorbia heterophylla, two from Amaranthus sp. and three from soybean). Isolates were analysed using PCR of the gumD gene and BOX-PCR, followed by multilocus sequence analysis (MLSA) of dnaK, fyuA, gyrB and rpoD genes. Representative isolates from MLSA clades and hosts were evaluated for pathogenicity on onion, E. heterophylla, Amaranthus retroflexus, soybean and common bean. Phylogenomic, type III secretion system (T3SS) effector and copper-insensitivity gene analyses were also performed. BOX-PCR revealed 11 haplotypes, some present within the same cultivar in different locations and year samples, as well as in coexisting weeds and crop species. Molecular analyses confirmed all isolates as Xanthomonas euvesicatoria, though not all onion isolates clustered with GenBank strains previously designated X. euvesicatoria pv. allii. The T3SS effector analysis identified a conserved core of 13 effectors, along with unique profiles such as XopR. No copper-insensitivity genes were detected. Onion isolates infected legumes and the weeds, whereas Amaranthus and soybean isolates did not infect onion. These findings emphasise the epidemiological relevance of managing weeds and soybean volunteers in onion fields, particularly during the summer season. Thu, 01 Jan 2026 00:00:00 GMT https://www.alice.cnptia.embrapa.br/alice/handle/doc/1189007 2026-01-01T00:00:00Z https://www.alice.cnptia.embrapa.br/alice/handle/doc/1188992 Título: Biochemical changes and antioxidant enzyme activity in alstroemeria flowers postharvest. Autoria: GAMA, A. B. N. da; BRITO, O. G.; COSTA, A. L. da; SILVA, D. P. C. da; PAIVA, P. D. de O. Conteúdo: Premature leaf yellowing, which is correlated to a decline in flower quality, represents a major challenge to the postharvest handling and commercialization of alstroemeria (Alstroemeria hybrida). Preservative solutions have been used as a strategy to address this problem. However, the results reported so far remain inconclusive. While these preservative solutions may delay senescence, their relationship with biochemical processes, particularly with ethylene and antioxidant enzymes, remains unclear. Therefore, the objective was to evaluate the effectiveness of different preservative solutions in maintaining postharvest quality and assessing the biochemical responses of Alstroemeria hybrida ‘Akemi’ floral stems. Alstroemeria flowers were harvested, sanitized, standardized, and subsequently placed in preservative solutions. The treatments consisted of different solutions prepared with 200 mg L–1 6-benzyladenine (BA), 10 g L–1 FloraLife Crystal Clear® (CRY), 0.05 mL L–1 Florissant 210XC + Chlorine (FLO + Cl) combined with 0.03 g L–1 Cl, 0.1 mM gibberellic acid (GA3), and 2 mM silver thiosulfate (STS) (applied as a pulsing treatment). Out of all the treatments, GA3 and FLO + Cl with chlorine provided the longest postharvest durability of floral stems. Preservative solutions prepared with GA3 or FLO + Cl with chlorine were effective in delaying leaf yellowing in alstroemeria. The use of STS in a pulsing solution was efficient in preventing perianth abscission. The antioxidant enzymes catalase (CAT), peroxidase (POD), superoxide dismutase (SOD), and ascorbate peroxidase (APX) contributed to reducing hydrogen peroxide (H2O2) accumulation in the flowers and showed higher activity during the harvest and commercialization phases. Thu, 01 Jan 2026 00:00:00 GMT https://www.alice.cnptia.embrapa.br/alice/handle/doc/1188992 2026-01-01T00:00:00Z https://www.alice.cnptia.embrapa.br/alice/handle/doc/1188980 Título: Caracterização dos polos de produção e de produtores de cenoura no Brasil. Autoria: PEDROSO, M. T. M.; FERREIRA, Z. R. Conteúdo: Tem por objetivo caracterizar os polos de produção e de produtores de cenoura no Brasil para orientar políticas públicas e pesquisas. Como metodologia analisou os dados do Censo Agropecuário 2017, do IBGE, para mapear o perfil tecnológico regional. Obteve um retrato detalhado do setor hortícola, identificando gargalos e disparidades entre os polos. Thu, 01 Jan 2026 00:00:00 GMT https://www.alice.cnptia.embrapa.br/alice/handle/doc/1188980 2026-01-01T00:00:00Z https://www.alice.cnptia.embrapa.br/alice/handle/doc/1188708 Título: Biomassa teor de mucilagem e acúmulo de macronutrientes em Plantago major L. em decorrência de doses de vermicomposto e épocas de colheita. Autoria: GRANAT, S.; SOUZA, A. F.; MESQUITA FILHO, M. V. de; MING, L. C.; CONAGIM, A. Conteúdo: Avalia a biomassa, teor de mucilagem e acúmulo de macronutrientes em Plantago major L. sob doses de vermicomposto e épocas de colheita. Testa 5 doses (0 a 80 t/ha) em 3 épocas (40, 70 e 100 dias) em Latossolo Vermelho. Conclui que as doses de vermicomposto exerceram efeitos de modo diferencial sobre componentes de biomassa de Plantago major L. Tue, 01 Jan 2002 00:00:00 GMT https://www.alice.cnptia.embrapa.br/alice/handle/doc/1188708 2002-01-01T00:00:00Z