Cobertura de polietileno e fontes de adubo podem reduzir bicho-mineiro e ácaro-vermelho em cafeeiro? / Can polyethylene cover and fertilizer sources reduce leaf miner and red mite in coffee?

A cafeicultura vem crescendo cada vez mais no Brasil e, diante disso, tecnologias são desenvolvidas constantemente para obtenção de maiores produtividades. Nesse contexto, vem sendo estudado o efeito do mulching de polietileno e fontes de adubo na cafeicultura. O objetivodesse trabalho foi avaliar a incidência de bicho-mineiro e ácaro-vermelho em cafeeiro em função do uso do mulchingde polietileno e adubos (liberação controlada e convencional). A pesquisa foi realizada na área experimental da Universidade Federalde Uberlândia ­CampusMonte Carmelo, Minas Gerais, com a cultivar de Coffea arabicaIPR 100, com delineamento em blocos casualizados e quatro repetições. Foram testados os seguintes tratamentos: T1 -mulchingdupla face branco/preto com adubo convencional; T2 ­mulchingdupla face branco/preto com adubo de liberação controlada; T3 ­mulchingdupla face prata/preto com adubo convencional; T4 ­mulchingdupla face prata/preto com adubo de liberação controlada; T5 ­Sem mulchingcom adubo convencional; T6 ­Sem mulchingcom adubo de liberação controlada. As avaliações ocorreram quinzenalmente de julho de 2020 a dezembro de 2020, mediante a constatação da presença ou ausência de ácaro-vermelho e de lagartas de bicho-mineiro. Os picos de densidade populacional para bicho-mineiro ocorreram no período de julho a outubro de 2020, e para ácaro-vermelho no mês de agosto, devido à baixa umidade relativa do ar e precipitação. Assim, conclui-se que a utilização do mulchingdupla face prata/preto proporcionou maior atratividade do bicho-mineiro-do-cafeeiro. Já as fontes de adubo não influenciaram na probabilidade de ocorrência deste inseto-praga. Além disso, os adubos convencionais, bem como os de liberação controlada, e a ausência/presença de coberturas do solo, não influenciaram na incidência deácaro-vermelho em cafeeiros da região do Cerrado Mineiro.(AU)

Coffee crop has been growing increasingly in Brazil and, in view of this, technologies are constantly being developedto obtain greater productivity. In this context, the effect of polyethylene mulchingas a source of fertilizer on coffee production has been studied. The objective of this work was to evaluate the incidence of leaf miner and red mite in coffee as a function of the use of polyethylene mulching and controlled and conventional release fertilizer. The research was carried out in the experimental area of the Federal University of Uberlândia -Campus Monte Carmelo, Minas Gerais, with the cultivar IPR 100, in arandomized block design with four blocks. The following treatments were tested: T1 -double-faced white/black mulchingwith conventional fertilizer; T2 ­white/black double-sided mulchingwith controlled release fertilizer; T3 ­double-sided silver/black mulchingwith conventional fertilizer; T4 ­silver/black double-sided mulchingwith controlled release fertilizer; T5 ­No mulchingwith conventional fertilizer; T6 ­No mulchingwith controlledreleasefertilizer. The evaluations took place fortnightly from July 2020 to December 2020, upon verification of the presence or absence of leaf miner and red mite caterpillars. Population density peaks for leaf miner occurred from July to October 2020, and for red mite in August, due to low relative humidity and precipitation. Thus, it is concluded that the use of double-sided silver/black mulching provided greater attractiveness to the coffee leaf miner. The fertilizer sources did not influence the probability of occurrence of this insect pest. In addition, conventional fertilizers, as well as those of controlled release, and the absence/presence of soil coverings, did not influence the incidence of red mite in coffee trees in the Cerrado Mineiro region.(AU)

Mite and pet allergen exposure in hotels in Uberlândia, Midwestern Brazil.

UNLABELLED: Mite allergens are involved in airway sensitization and allergic diseases. We evaluated the exposure to house dust-mite (Der p 1 and Der f 1) and pet (Fel d 1 and Can f 1) allergens in hotels in Uberlândia, Midwestern Brazil. A total of 140 dust samples were collected from bedding (n = 98) and carpet (n = 42) of bedrooms in 20 hotels enrolled for this study. Geometric mean (GM) levels of Der f 1 (11.30 microg/g of dust; 95% CI: 8.34-15.30 microg/g) were significantly higher than Der p 1 (0.15 microg/g of dust; 95% CI: 0.13-0.18 microg/g) in bedding dust samples (P < 0.001), regardless of the hotel classes. Der f 1 levels were significantly higher in bedding (11.30 microg/g of dust; 95% CI: 8.34-15.30 microg/g) than carpet (6.32 microg/g of dust; 95% CI: 4.31-9.26 microg/g) dust samples (P < 0.05). High levels of Der f 1 (>10 microg/g of dust) were found in 58%, 76%, and 69% of dust samples from Simple, Economical, and Tourist/Superior hotels, respectively, while GM levels of Fel d 1 (0.11 microg/g of dust; 95% CI: 0.09-0.14 microg/g) and Can f 1 (0.30 microg/g of dust; 95% CI: 0.20-0.44 microg/g) were relatively low. These results indicate that Der f 1 is the predominant allergen in hotels in Uberlândia, especially in bedding dust samples, regardless of the hotel classes and could represent an important risk factor for exacerbation of allergic symptoms in previously mite-sensitized guests. PRACTICAL IMPLICATIONS: Mites and pets are important sources of indoor allergens. Most people spend the greatest part of their time indoors. Hotels can constitute an important allergen reservoir of the indoor environment and could represent an important risk for exacerbation of allergic symptoms in previously sensitized guests. Thus, hotels should also be included for planning indoor allergen avoidance as part of a global management strategy, especially in patients with respiratory allergy.

Characterization of allergenic components from house dust mite Dermatophagoides siboney. Purification of Der s 1 and Der s 2 allergens.

BACKGROUND: Allergic reactions to house dust mites of the genus Dermatophagoides play an important role in the pathogenesis of asthma and other atopic diseases. Dermatophagoides siboney has been described as a species from Cuba. Together with D. pteronyssinus and Blomia tropicalis, it is frequently found in house dust from homes of asthmatics. OBJECTIVES: The aim of this study was to investigate the allergenic composition from the house dust mite D. siboney. METHODS: The characterization of D. siboney extract was performed by SDS-gPAGE and immunoblotting. Purification of individual components was performed by affinity chromatography. RESULTS: At least 16 components between 13 and 98 kDa stained by Coomassie Blue were found. Using a panel of 35 sera from atopic mite sensitive patients 13 components reacted to different extent with patient IgE. Two components, 25 and 14 kDa, bound to specific IgE strongly and frequently, i.e. 80 and 91% of the patients, respectively. Affinity chromatography using crossreacting monoclonal antibodies to group 1 and 2 allergens resulted in purified preparations of 25 and 14 kDa proteins, which showed IgE-binding with the majority of the human sera when tested by immuno-dot. CONCLUSION: Based on the IgE binding profile of D. siboney and on the capacity to react with crossreacting monoclonal antibodies for groups 1 and 2, it is proposed to name these two allergens, 25 and 14 kDa, Der s 1 and Der s 2, respectively.

Identification of allergens from the mite Blomia tropicalis.

In some tropical areas the mite Blomia tropicalis is a clinically important allergenic component of house dust, inducing specific IgE immune response in patients with allergic respiratory diseases such as asthma and rhinitis. The identification of allergens of this mite is necessary to obtain appropriate reagents for diagnostic and treatment procedures. We carried out this study using immunoblotting to detect the allergens of B. tropicalis. Our results demonstrate that this mite has one major allergen (11-13 kDa) and three other important allergens with about 50% binding (64, 36 and 33 kDa). Therefore, B. tropicalis should be regarded as an important source of allergens in the house dust in tropical areas, besides those derived from other mites.