https://www.alice.cnptia.embrapa.br/alice/handle/item/250 Artigo em periódico indexado (CNPMS) 2026-07-02T23:17:26Z https://www.alice.cnptia.embrapa.br/alice/handle/doc/1187979 Título: Impact of Kappaphycus alvarezii biostimulant on growth, biochemistry, essential oil, and rhizosphere of basil (Ocimum basilicum) plants. Autoria: NUNES, A.; MINELLO, L. V. P.; OLIVEIRA, E. R.; SCHNEIDER, A. R.; DUTRA, F. de S.; GUIZOLFI, T.; SANTOS, L. R. B.; GELLI, V. C.; GRANADA, C. E.; SPEROTTO, R. A.; MOURA, S.; MARASCHIN, M.; LIMA, G. P. P. Conteúdo: Seaweed-derived biostimulants are a promising strategy for improving crop performance in sustainable agriculture. In this context, this study evaluated the effects of foliar application of Kappaphycus alvarezii extracts, obtained from two Brazilian regions (São Paulo: Kal-SP and Santa Catarina: Kal-SC), at different concentrations (1%, 3%, 5%, and 7%) on the growth, biochemical profile, essential oil yield, and rhizosphere microbiome of Ocimum basilicum under field conditions. Morphological analysis indicated that the 5% and 7% concentrations increased plant height, biomass, root development, and inflorescence production, with biomass gains of up to 51% and essential oil production increases of up to 142% compared to the control. Biochemical responses varied by extract origin, with Kal-SC promoting greater increases in photosynthetic pigments, antioxidant activity, and carbon-related metabolites, whereas Kal-SP induced only minor metabolic changes. The algal biostimulant modulated essential oil yield and composition, promoting treatment-dependent shifts in major terpenoid compounds. Microbiome analysis showed no significant changes in alpha diversity, but significant shifts in beta diversity and functional groups, such as Bacillaceae, indicating rhizosphere reorganization. Overall, the effectiveness of K. alvarezii-based biostimulants depends on concentration and biomass source, highlighting their potential as sustainable agricultural bioproducts and the importance of standardized extraction for consistent outcomes. 2026-01-01T00:00:00Z https://www.alice.cnptia.embrapa.br/alice/handle/doc/1187983 Título: Spirulina-derived carbon dots promote context-dependent effects on rice metabolism, yield, and grain quality under non-stress and heat stress conditions. Autoria: MINELLO, L. V. P.; SANTOS, S. L. dos; LONGARAY, L. B.; FAGUNDES, N. da S.; DEUNER, S.; NUNES, A.; OLIVEIRA, E. R.; MARASCHIN, M.; SPEROTTO, R. A. Conteúdo: Carbon dots (CDs) have emerged as promising nanobioinputs capable of modulating plant metabolism and stress responses. However, their effectiveness under field conditions remains poorly understood. This study evaluated the effects of Spirulina-derived carbon dots (S-CDs) on rice metabolic, agronomic, and grain-quality responses under non-stress and heat stress conditions. Two independent field experiments were conducted under ambient and heat stress conditions, the latter imposed using temporary greenhouse structures during the reproductive stage. S-CDs were applied by foliar spraying (0.2 mg mL−1 ) at key developmental stages. Their effects were assessed through metabolic, agronomic, and grain quality analyses. Under non-stress conditions, daily average temperatures ranged from 20 to 27 ◦C, while daily maxima ranged from 24 to 38 ◦C. Heat stress increased daily average temperature by 3.9 ◦C and daily maximum temperature by 12.5 ◦C, with temperature peaks frequently exceeding 45 ◦C for several hours. Under non-stress conditions, S-CDs induced modest changes in antioxidant, carbon, and nitrogen metabolism, but without consistent improvements in grain yield or yield components. Under heat stress, however, S-CD application reduced spikelet sterility and increased grain yield despite limited changes in the metabolic variables evaluated. Grain quality and nutritional composition also responded differently depending on the environmental condition, indicating context-dependent effects. S-CDs showed limited agronomic relevance under favorable field conditions, but contributed to yield stability under heat stress. These findings support the potential of SCDs as complementary nanobiostimulants to improve rice resilience under climate-related stress conditions. 2026-01-01T00:00:00Z https://www.alice.cnptia.embrapa.br/alice/handle/doc/1187981 Título: Food system resilience requires moving beyond zero-sum growth-defense frameworks. Autoria: SPEROTTO, R. A.; MINELLO, L. V. P.; CABRAL, T. P. da S.; CAMPOS, M. L. N.; ALMEIDA, F. A. Q. de; CAMPOS, M. L. Conteúdo: Agricultural systems are increasingly challenged by climatic instability, pest outbreaks, and pressure to reduce dependence on external inputs. However, agricultural evaluation systems remain strongly focused on productivity under optimal conditions, with less emphasis on resilience and adaptive capacity. One driver of this bias is the longstanding assumption that plant growth and defense are inherently antagonistic. Although plant biology now shows that growth and defense are dynamically coordinated rather than strictly competitive, this vision remains poorly integrated into agronomic evaluation and policy. In this Perspective we argue that persistent zero-sum interpretations of growth-defense relationships may constrain how resilience, stress tolerance, and sustainability are integrated into agricultural evaluation systems. Reframing growth-defense antagonism as a systems and policy problem may help align agricultural evaluation frameworks with the multifunctional demands imposed by climate change and sustainable food production. 2026-01-01T00:00:00Z https://www.alice.cnptia.embrapa.br/alice/handle/doc/1187769 Título: Proteção antecipada: evento avalia como cigarrinhas-do-milho sadias e infectivas respondem ao mesmo tratamento de sementes. Autoria: REDOAN, A. C. M.; MARQUES, V. M.; SOUZA, I. R. P. de; OLIVEIRA, I. R. de; MENDES, S. M. Conteúdo: Um dos desafios encontrados para o manejo do complexo dos enfezamentos no campo está no fato de não ser possível identificar se uma cigarrinha-do-milho (Dalbulus maidis) (Figura 1) está sadia ou infectada pelos patógenos causadores dos enfezamentos, nem estimar a proporção dessas infectadas nas lavouras. Esse conhecimento pode realmente afetar o posicionamento do controle (momento ideal de entrar com o manejo da praga) e o custo final da produção. Por isso, os produtos precisam ter alta eficiência, garantindo proteção principalmente na fase inicial da cultura, nos estádios vegetativos do V2 (desenvolvimento de duas folhas completamente formadas) ao V6 (seis folhas completamente formadas), que é a considerada mais crítica, pois quanto mais cedo a planta for infectada, maior será o impacto na produção. 2026-01-01T00:00:00Z