DSpace Coleção: Artigo em periódico indexado (CNPMF)

Variabilidade de fosforo, potassio e materia organica no solo em relacao a sistemas de manejo.

Thu, 01 Jan 1998 00:00:00 GMT

Título: Variabilidade de fosforo, potassio e materia organica no solo em relacao a sistemas de manejo. Autoria: SOUZA, L. D. S.; COGO, N. P.; VIEIRA, S. R. Conteúdo: A variabilidade espacial de fosforo, potassio e materia organica foi avaliada em diferentes solos e sistemas de manejo. Em Elaborado do Sul (RS), o trabalho foi realizado, em agosto de 1990, em um Podzolico Vermelho-Escuro, Kandiudult, amostrando-se os sistemas de prepero convencional, plantio direto, escarificacao e pastagem, na malha de amostragem de 1x1 m e nas profundidades de 0-0,05 e 0,05-0,20 m. Em Passo Fundo (RS), em novembro de 1991, foram amostrados dois tipos de solos: Latossolo Roxo, Hapludox (preparo convencional e plantio direto) e Latossolo Vermelho-Escuro, Hapludox (pastagem), na malha de amostragem de 10x10 m e nas profundidades de 0-0,10, 0,10-0,20 e 0,20-0,30 m Em Passo Fundo, nos sistemas cultivados, foi avaliada tambem a variabilidade da producao de trigo, colhendo-se areas de 1 m, As maiores variabilidades foram encontradas para fosforo e potassio, com seus valores no solo tendendo para uma distribuicao lognormal. Na maioria dos casos, houve correlacao espacial para as propriedades do solo nos sistemas de manejo avaliados, assim como para a producao de trigo. O plantio direto apresentou maiores coeficientes de variacao e menores alcances de dependencia espacial, assumindo-se ter ele determinado maior variabilidade das variaveis analisadas que os demais sistemas; na pastagem, ocorreu a menor veriabilidade do solo. No plantio direto, observou-se, ainda, correlacao esoacial cruzada positiva da producao de trigo com fosforo, com materia organica.

Traditional and transgenic strategies for controlling tomato-infecting begomoviruses.

Tue, 01 Jan 2002 00:00:00 GMT

Título: Traditional and transgenic strategies for controlling tomato-infecting begomoviruses. Autoria: ASTUA, J. de F.; PURCIFULL, D. E.; POLSTON, J. E.; HIEBERT, E. Conteúdo: Viruses of to the family Geminiviridae are considered some of the most important pathogens in tropical and subtropical regions of the world. Members of one Geminiviridae genus, Begomovirus, have been causing severe losses, particularly in tomato (Lycopersicon esculentum) production in the Americas and the Caribbean. Several new begomoviruses have been reported in the region and, at least one, Tomato yellow leaf curl virus (TYLCV), has been brought in from the Old World via infected transplants. In addition, the recombination events that are playing an important role in Begomovirus diversity have increased the complexity of their control. This scenario has led to the search for control measures that go beyond traditional host genetic resistance, chemical controls and cultural practices. In this review, besides the recommended classical control measures, transgenic approaches will be discussed, as well as the mechanisms involved in their successful control of viruses.

High-throughput sequencing in phytopathology: genomics-driven diagnostics and host-pathogen interactions.

Thu, 01 Jan 2026 00:00:00 GMT

Título: High-throughput sequencing in phytopathology: genomics-driven diagnostics and host-pathogen interactions. Autoria: PEREIRA, L. R.; BARRO, M. P.; HARAKAVA, R.; ASTUA, J. de F.; RAMOS-GONZÁLEZ, P. L. Conteúdo: ABSTRACT: Plant diseases severely constrain agricultural productivity, exacerbating food insecurity, economic instability, and environmental degradation. Global trade and climate change further intensify pathogen spread, emergence, and host shifts. While traditional diagnostics and targeted assays, such as polymerase chain reaction and enzyme-linked immunosorbent assay, improve specificity, they depend on prior knowledge and are limited in detecting novel or mixed infections. High-throughput sequencing (HTS) has emerged as a transformative, unbiased platform that allows comprehensive detection of known and unknown pathogens through metagenomics and transcriptomics. By generating large-scale genomic data, HTS supports pathogen discovery, epidemiological surveillance, quarantine systems, and genome-informed disease management. It underpins advanced strategies, including Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) and CRISPR-associated (Cas) proteins editing and RNA interference, and accelerates the breeding of resistance. Despite challenges – such as bioinformatics standardization, cost, and data interpretation – HTS, when integrated with classical diagnostics and biological validation, represents a foundational technology for sustainable, proactive plant health management and global phytosanitary resilience.

Sample size matters: optimizing fruit sampling for reliable quality assessment in sweet orange varieties

Thu, 01 Jan 2026 00:00:00 GMT

Título: Sample size matters: optimizing fruit sampling for reliable quality assessment in sweet orange varieties Autoria: CALDAS, M. J. M.; SASAKI, F. F. C.; RODRIGUES, V. da S.; SANTANA, L. G. L.; LEDO, C. A. da S.; GESTEIRA, A. da S.; PASSOS, O. S.; SOARES FILHO, W. dos S. Conteúdo: ABSTRACT: This study aimed to determine the optimal sample size of fruits from sweet orange varieties for the evaluation of their physical and chemical quality attributes. Twenty ripe fruits from the following varieties, namely, Diva, Hamlin CNPMF-020, Pera CNPMF-D6, Uruburetama Blood, and Valência Tuxpan CNPMF were used. The variables assessed included fruit mass, longitudinal and transverse diameters, juice mass and yield, peel color and thickness, soluble solids content, titratable acidity, the soluble solids/titratable acidity ratio (SS/TA), and a technological index. The experimental design was completely randomized, with individual analysis of each fruit. Data were analyzed using the Modified Maximum Curvature Method with the aid of the R statistical software. The optimal minimum number of fruits varied according to variety and variable. The smallest required sample sizes were four fruits for Pera CNPMF-D6, six fruits for Diva and Uruburetama Blood, and seven fruits for Valência Tuxpan CNPMF and Hamlin CNPMF-020. Therefore, a standardized sample size of seven fruits is recommended for studies based on the physicochemical quality of sweet orange varieties, to ensure sufficient precision and statistical reliability under the conditions of this study.