Federal University of Roraima

About: Federal University of Roraima is a based out in . It is known for research contribution in the topics: Population & Thermogravimetry. The organization has 981 authors who have published 1218 publications receiving 7849 citations. The organization is also known as: Federal University of Roraima.

First Report of Colletotrichum aeschynomenes and C. tropicale Causing Anthracnose on Myrciaria dubia in Brazil

Abstract: Camu-camu (Myrciaria dubia [Kunth] McVaugh) is a native fruit tree of Amazon region that produces fruit with high content of vitamin C. The enormous economic potential has encouraged its domestication process in the northern region of Brazil. Since 2016, brown, necrotic, anthracnose-like lesions were observed on 30 to 40% of the camu-camu plants in an experimental field located in the city of Boa Vista, Roraima, Brazil (2°52′20.7″ N; 60°42′44.2″ W). Small pieces of tissue taken from the lesions were surface disinfested previously (1 min in 70% alcohol, 1 min in 1% NaOCl, and rinsed with sterile water). Leaf sections were plated on water agar medium, incubated at 25°C for 4 days, and afterward were transferred to potato dextrose agar (PDA) medium. After 7 days on PDA at 25°C, the isolate CA3B formed a grayish-white colony. Conidia were hyaline, aseptate, subcylindrical with rounded ends, measuring (n = 20) 12.1 to 15.9 × 4.9 to 7.0 μm. Appressoria were brown, subglobose, clavate, measuring 7.4 to 16.7 × 4.6 to 9.9 μm. The isolate COL02 formed light gray colonies. Conidia were hyaline, aseptate, cylindrical, tapering slightly near both ends, measuring (n = 20) 12.3 to 16.1 × 4.7 to 6.5 μm. Appressoria were brown, mostly elliptic to subfusoid, deeply lobed, measuring 8.7 to 15.9 × 5.8 to 9.9 μm. Single-spore cultures were deposited in the Microorganisms Culture Collection of EMBRAPA Roraima, Roraima, Brazil. Total DNA was extracted, and fragments of glyceraldehyde-3-phosphate dehydrogenase (GAPDH), β-tubulin 2 (TUB2), glutamine synthetase (GS), and manganese-superoxide dismutase (SOD2) genes were amplified (Weir et al. 2012) and sequenced. The obtained sequences showed 94 to 100% identity with sequences published in GenBank of the Colletotrichum gloeosporioides species complex, with a predominance of C. tropicale, C. aeschynomenes, and C. siamense. Sequences from the two isolates were deposited in GenBank (accession nos.: GAPDH, MK792453, MK792457; GS, MK792454, MK792458; SOD2, MK792455, MK792459; and TUB2, MK792456, MK792460). Phylogenetic Bayesian inference analysis based in a combined data set (concatenated sequences of GAPDH, TUB2, GS, and SOD2) showed that the isolate CA3B clustered with the ex-holotype specimen of C. tropicale (CBS 124949), and the isolate COL02 clustered with the ex-type specimen of C. aeschynomenes (ICMP 17673) with high support (posterior probability = 1). To confirm the pathogenicity, five seedlings of the camu-camu were sprayed with 10⁶ conidia/ml spore suspension for each isolate. Five seedlings were sprayed with sterile water as a negative control. All seedlings were covered with plastic bags 24 h after inoculation and kept at 27°C in a greenhouse with a 12-h photoperiod. After 7 days, depressed and necrotic lesions were observed in the inoculated leaves. In the third treatment, both isolates were coinoculated. Negative control plants showed no symptoms. To fulfill Koch’s postulates, both species were successfully reisolated from the inoculated and coinoculated leaves by cultural morphology. In Brazil, C. tropicale causes anthracnose on different hosts, such as mango and soursop (Costa et al. 2019; Lima et al. 2013). C. aeschynomenes was associated with Aeschynomene virginica in the United States (Weir et al. 2012), cassava in Thailand (Sangpueak et al. 2018), and cacao in Brazil (Nascimento et al. 2019). To our knowledge, this is the first report of C. aeschynomenes and C. tropicale causing anthracnose on M. dubia worldwide.

Exposição ocupacional e perfil de pacientes oncológicos de regiões da fronteira agrícola amazônica em Rondônia

Abstract: A mortalidade por neoplasias vem crescendo consideravelmente ao longo das ultimas decadas e representa um importante problema de saude publica. Devido a importância do contexto que envolve essa doenca e ao alto indice de morbimortalidade, o objetivo deste trabalho foi caracterizar o perfil e os fatores de risco dos pacientes com câncer admitidos no Hospital Sao Daniel Comboni de Cacoal, que e tido como referencia no estado de Rondonia. Para tanto, os dados da pesquisa foram obtidos atraves da analise de 503 prontuarios dos pacientes admitidos ao longo de um ano, levando-se em consideracao sexo, raca, idade, estado civil, nivel de escolaridade, fatores de risco (historico familial, tabagismo e etilismo), profissao e orgao acometido. Com relacao ao perfil dos pacientes, 49,30% eram do sexo feminino e 50,70% do sexo masculino, 90,25% dos pacientes apresentavam mais de 40 anos, 67,58% eram de raca branca, 66% casados e 74,84% eram analfabetos ou com 1 o grau incompleto. Com relacao a ocupacao profissional, 41,31% dos pacientes eram trabalhadores rurais e a maioria dos pacientes (66,84%) apresentava um ou mais fatores de risco associados. Os principais tipos de câncer que acometeram os pacientes foram de prostata (22,27%) e de mama (19,49%). Conclui-se que e possivel que a raca branca e o baixo nivel de escolaridade associados a exposicao ocupacional inerente ao trabalho agricola (exposicao excessiva, sem protecao, a agrotoxicos e radiacao solar) podem ter tido influencia na carcinogenese, indicando necessidade de implementacao de politicas de prevencao ao câncer em regioes com importante atividade agricola.

Morfologia de plântulas de Martiodendron excelsum e sua relevância sistemática em Dialiinae (Leguminosae, "Caesalpinioideae”)

Abstract: Martiodendron Gleason e um genero sul-americano com cinco especies arboreas, subordinado a Dialiinae (tribo Cassieae). Dialiinae apresenta 17 generos, que formam um clado cujas relacoes genericas permanecem em grande parte nao definidas. Este trabalho descreve e ilustra o desenvolvimento e a morfologia de plântulas de Martiodendron excelsum e avalia, por meio de uma revisao, a relevância sistematica dos atributos de plântulas em nivel de genero em Dialiinae. Sementes de M. excelsum foram coletadas de populacoes em areas de mata ciliar no Estado de Roraima, Brasil. Martiodendron excelsum tem plântulas fanero-epigeo-armazenadoras, eofilos estipulados e 1-foliolados nos tres primeiros nos. Os dados sobre morfologia de plântulas sao potencialmente uteis para diagnosticar generos em Dialiinae, visto que Martiodendron e todos os demais generos podem ser distintos entre si pela a variacao no grupo morfologico de plântulas, na filotaxia e numero de foliolos no primeiro e segundo eofilos, nas relacoes entre o comprimento e largura dos cotiledones e entre o comprimento do hipocotilo e epicotilo e no alongamento do primeiro entreno eofilar. Por fim, em Leguminosae, a predominância de eofilos 1-foliolados na maior parte dos generos de Dialiinae e somente comparavel a encontrada entre as plântulas de taxons de Papilionoideae.

Suplementação de lipídeos de diferentes fontes em dietas para vacas Jersey na fase inicial de lactação

Abstract: The objective of this research was to evaluate the effects of fat supplementations as calcium salts of palm oil (PF), whole rice bran + rice oil (WRBO) and whole rice bran + bovine tallow (WRBT) on dry matter intake, productive efficiency and energy balance of dairy cows in the beginning of the first third period of lactation. Control diet contained 2.9% EE, while the diets GP, FAIO and FAIS contained 5.13; 5.29 and 5.16% EE, respectively. Pure bred Jersey cows of 2nd and 3rd lactation were used, with 70 days in milk, average weight of 420 kg and body condition of 3.5 to 4. A replicated 4 x 4 Latin square experimental design was used, with eight cows, four diets and four experimental periods. Each experimental period consisted of 21 days (14 days for adaptation and 7 for sample collection for the chemical analysis of milk and feeds. Milk production of 3.5% fat corrected milk (FCM 3.5%) was higher with the fat supplementation to the diet. There was no difference in dry matter intake. Fat supplementation showed better results for productive efficiency expressed as FCM3.5% in function of metabolic weight. Independently of lipid source, there was not effect of the diets on PLC3.5%, dry matter intake and productive efficiency, expressed as PLC3.5% in function of the metabolic weight. The addition of different fat sources to high production dairy cows diets could be viable, because its addition to the diet improved milk yield without alter feed intake.