Attack by the coffee berry borer Hypothenemus hampei causes significant damage to coffee crops because it affects the quality of the coffee fruit during different developmental stages, which results in production losses. Control of the borer is difficult owing to its cryptic behavior and the fact that it spends its entire life cycle inside the coffee berries. This makes it difficult for natural enemies to reach it, as well as for it to come into contact with chemical insecticides. The objective of the present study was to select and evaluate the virulence of entomopathogenic nematodes (EPNs) on the coffee berry borer H. hampei and their compatibility with the insecticide cyantraniliprole under laboratory conditions. Initially, the pathogenicity and virulence of 16 isolates of Steinernema and Heterorhabditis towards coffee berry borer larvae and adults were evaluated. The most virulent isolates to both larvae and adults were determined by topical inoculation tests in coffee fruits (berries) infested by the insect, using a concentration of 100 infective juveniles (IJs)/fruit. The same isolates were also evaluated for viability and infectivity when combined with cyantraniliprole. The isolates S. feltiae (IBCB-n 47) and Heterorhabditis amazonensis (GL) displayed the highest virulence towards adults (54% ResumoA broca-do-café Hypothenemus hampei causa significativos prejuízos a esta cultura, pois seu ataque afeta a qualidade dos frutos de café em seus diferentes estádios de desenvolvimento e consequentemente leva a perdas na produção. O controle é dificultado devido ao seu comportamento críptico, uma vez que passa todo o ciclo dentro dos frutos de café, dificultando a ação de inimigos naturais, bem como o contato com inseticidas químicos. O objetivo deste estudo foi avaliar a virulência de nematoides entomopatogênicos (NEPs) sobre a broca-do-café H. hampei e a sua compatibilidade com o inseticida ciantraniliprole em condições de laboratório. Inicialmente, foram avaliadas a patogenicidade e virulência de 16 isolados de Steinernema e Heterorhabditis para larvas e adultos de H. hampei. Os isolados mais virulentos para larvas e adultos foram utilizados no teste de inoculação tópica em frutos de café infestados pelo inseto, utilizando uma concentração de 100 juvenis infectantes (JIs)
Infestations of Dichelops melacanthus (Dallas; Hemiptera: Pentatomidae) in corn and wheat in Brazil, and the subsequent damage, have increased in recent years, mainly owing to this insect’s ability to survive the off-season. The control of this insect is mainly carried out with chemical insecticides, but the development of alternative methods, such as biological control, can contribute to a more sustainable management. Thus, the objective of this study was to evaluate the potential of entomopathogenic nematodes (EPNs) for the control of D. melacanthus. A selection test was performed with 15 isolates of genera Steinernema and Heterorhabditis regarding their pathogenicity and virulence on adults of D. melacanthus. Concentration (10, 20, 40, 50, and 100 infective juveniles (IJs)/cm2) and greenhouse tests were carried out only with the Steinernema feltiae isolate (IBCB-n 47). All experiments were conducted in a completely randomized design. The selection test data were submitted to the Scott-Knott averages test (P ? 0.05), and those from the greenhouse test to the Student's t-test. The results of the concentration assay were subjected to regression analysis. All isolates showed pathogenicity and virulence in adults of D. melacanthus. The isolates GL (Heterorhabditis amazonensis), IBCB-n27 (Steinernema sp.), and RSC05 (H. amazonensis) were the most virulent (80.0, 82.0, and 88.0% mortality, respectively). The higher concentrations of S. feltiae (50 and 100 IJs/cm²) were responsible for the highest mortality rates of green belly stink bug (88.0 and 86.0%, respectively). In the greenhouse test, S. feltiae caused higher mortality (38%) than the control.
We present the first report on Euphoria lurida (Fabricius) (Coleoptera: Scarabaeidae) infestation on safflower (Carthamus tinctorius L.), a crop of industrial and medicinal importance. Between September and October 2013-2015 in Paraná State, we observed E. lurida adults feeding on safflower plants from the inception of flower head formation onwards, over an area of approximately 400 m. Losses in the productivity of infested plants were estimated between 15 and 50%. The damage was characterized by perforations in the upper portion and at the base of the developing flower heads or open flowers, resulting in withering and abortion of the reproductive structures.
The objective of this study was to evaluate the infestation of Vatiga illudens in cassava varieties and to correlate its infestation with the physical and morphological parameters of resistance. The experiments were conducted in the 2014/2015 and 2016/2017 seasons, out in a randomized complete block design with nine treatments and five replicates. Nymphs and adults of V. illudens were evaluated on the abaxial surface of 16 leaves of the middle third of the plant. The density of trichomes was quantified with the use of electron micrographs, and the roughness of the epicuticular wax was assigned to the leaves of the shoot and the apical third. The color components L*, a*, b*, were measured with a portable digital colorimeter. The cultivars IAC 90 and Santa Helena demonstrated the smallest infestations in the 2014/2015 season and maintained low infestation in the 2016/2017 season. The varieties Baianinha, IAC 576-70 and Catarina-Branca, maintained high infestations in the both seasons. The density of trichomes of the middle third of the plants correlated negatively to the V. illudens infestation for the two seasons. The higher density on trichomes, negatively affects the infestation of V. illudens in cassava varieties, characterizing as a specific resistance factor to this species.
Objetivou-se selecionar isolados nativos de nematoides entomopatogênicos (NEPs) e avaliar o efeito da cama de aviário na sua patogenicidade e virulência, visando o controle do cascudinho de aviário. Foram utilizados 18 isolados (Steinernema e Heterorhabditis) no teste de seleção e os três isolados mais virulentos foram utilizados no teste de concentrações (10, 20, 40, 50 juvenis infectantes (JIs)/cm²). O efeito da cama de aviário (nova e velha) foi avaliado sobre S. feltiae (IBCB-n 47), S. carpocapse (IBCB-n 02), H. bacteriophora e H. amazonensis (UEL 08). Os experimentos foram realizados em delineamento inteiramente casualizado. Os dados do teste de seleção e efeito da cama foram submetidos ao teste de médias Scott-Knott (P?0,05) e, do teste de concentrações à análise de regressão. Observou-se no teste de seleção para adultos, que os três isolados mais virulentos foram Heterorhabditis amazonensis (UEL 07), H. amazonensis (RSC 05) e Steinernema carpocapsae (IBCB-n 02) com 76,5; 73,5; 70% mortalidade respectivamente. Para larvas, Heterorhabditis sp. (NEPETT 11), S. feltiae (IBCB-n 47), H. amazonensis. (UEL 07) foram os mais virulentos e causaram 100; 96; 93,7% de mortalidade respectivamente. No teste de concentrações, a maior mortalidade em adultos (98%) e larvas (98%) foi observada para S. feltiae nas concentrações de 30 JIs/cm² e 50JIs/cm² respectivamente. Com relação ao efeito da cama de aviário, observou-se que S. feltiae (IBCB-n 47) e S. carpocapse (IBCB-n 02) causaram as maiores mortalidade tanto em cama nova (60,7 e 58,7%) quanto em cama velha (80 e 74,7%) respectivamente.
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