Faculdade de Estatística - FAEST/ICEN

URI Permanente desta comunidadehttps://repositorio.ufpa.br/handle/2011/4053

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Agora exibindo 1 - 2 de 2

Acesso aberto (Open Access)
Economic injury level of citrus black-fly in commercial ‘pera-rio’ orange area
(Universidade Federal do Pará, 2017-07) LIMA, Bruno Gonçalves; FARIAS, Paulo Roberto Silva; RAMOS, Edson Marcos Leal Soares; SALES, Tiago de Melo; SILVA, Anderson Gonçalves da
Citrus black-fly (Aleurocanthus woglumi) has become an important pest in many citrus-producing regions in Brazil, causing direct and indirect damage to plants. Due to the lack of studies on the economic injury level (EIL) for this insect, control efficiency can be impaired. The objective of this research was to determine the EIL and the influence on the productivity of orange trees colonized by A. woglumi nymphs in an orchard located in the municipality of Capitao-Poço, Pará, using statistical analysis and damage prediction models through multivariate statistics. Population levels varied along the experiment. Infestation by A. woglumi nymphs negatively influenced orange production in Capitao-Poço with the highest population densities of the pest associated to lower plant productivity. The level of A. woglumi infestation on orange trees resulting in economic losses was, on average, 47.63% of infested plants, ranging from 22.75 to 89.92% and EIL is expressed by equation Y = 97.39 – 8.43x.
Acesso aberto (Open Access)
Modelo de efeitos fixos com medida repetida aplicado em experimentos de melhoramento genético do cupuaçuzeiro
(Universidade Federal do Pará, 2015-12) ALVES, Rafael Moysés; TAVARES, Maria Regina Madruga; TAVARES, Héliton Ribeiro; LOBATO, Tarcísio da Costa; OLIVEIRA, Terezinha Ferreira de
This study was conducted to evaluate vegetative performance of cupuassu progenies, in the immaturity phase, through analysis of repeated measures. The experimental area was installed in the municipality of Tomé Açu, Northeast of the state of Para. We employed 25 full-sib progeny of cupuassu, who had vegetative growth (height and diameter of the plant), monitored for three years. Because of the nature of longitudinal observations it was assessed primarily through Mauchly sphericity test, which type of statistical analysis should be applied. For the variable diameter, sphericity condition was not violated, therefore, proceeded to review the design scheme of split plot. For the height variable, the test was significant, indicating necessarily evaluate the best structure to explain the correlation of errors, being chosen the covariance structure Heterogeneous Composed Symmetry. Differences were found between the progenies only in the third year of evaluation, and the variable diameter of the plant allowed better discriminate the progenies.

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Navegando Faculdade de Estatística - FAEST/ICEN por Periódicos "Revista Brasileira de Fruticultura"