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Serpentine leafminer (Liriomyza trifolii) on potato (Solanum tuberosum): field observations and plant photosynthetic responses to injury
Bueno, Adeney de Freitas;Zechmann, Benjamin;Hoback, William Wyatt;Bueno, Regiane Cristina Oliveira de Freitas;Fernandes, Odair Aparecido;
Ciência Rural , 2007, DOI: 10.1590/S0103-84782007000600001
Abstract: serpentine leafminers, liriomyza spp. (diptera: agromyzidae), are polyphagous insects that feed on numerous crops worldwide including potato. recently, leafminer larvae (liriomyza trifolii) have become an economically important pest of potato. the larvae eat the mesophyll of leaflets leaving long winding tunnels inside the leaflets. the photosynthetic effects of larval tunneling on the remaining leaf tissue are unknown. in 2003, physiological responses of potato to leafminer, l. trifolii were evaluated in kearney, nebraska, usa. the leaflets were examined 7 and 14 days post infestation for leaf area injury, photosynthetic rates and fluorescence. leafminers caused up to 13% leaf area loss due to leafminer injury with no effect on the photosynthetic rates of the remaining leaf tissue thus having similar effects as other gross tissue removers. however, fluorescence measures revealed changes in the photosynthetic efficiency and depend of the type of injury, it may lead to early leaf senescence. field monitoring of l. trifolii infestations showed that treatments with abamectin were effective in reducing leafminer numbers and had no immediate effect on beneficial parasitoid from eulophidae family suggesting that abamectin is a good option for chemical control.
Effects of Bacillus thuringiensis on Larval Serpentine Leafminers Liriomyza trifolii (Burgess) (Dipetera: Agromyzidae) in Bean  [PDF]
Emine Cikman,Nuray Comlekcioglu
Pakistan Journal of Biological Sciences , 2006,
Abstract: This study aimed to investigate the effects of Bacillus thuringiensis on Liriomyza trifolii (Burgess) (Dipetera: Agromyzidae). L. trifolii is an important pest in vegetable growing areas in Sanliurfa, Turkey. Field trials were carried out in the experimental field of Faculty of Agriculture in Harran University through the July to November in 2005, employing randomized complete block design with three replicates. Adults of L. trifolii were obtained from laboratory culture and 5 and 5 and adults of L. trifolii were inoculated each plots at the first week of the production period. B. thrungiensis Berliner was applied at a concentration of 60x106/mg Bacillius thrungiensis spore. B. thrungiensis was applied at the recommended rate of 75 g/100 L water. Application dates were set when the pest density reached a level of 4-5 larvae/leaf which are economic threshold. The application of B. thrungiensis was done the 3rd week and application continued once a 15 day throughout the 9th week production periods, because the pest density reduced a level of 4-5 larvae/leaf the last 5 weeks. Total application of B. thrungiensis was 4 times throughout the bean production period. The leaves were sampled weekly from B. thuringiensis treated and non-treated plots and kept in laboratory under observation to compare the number of emerging leaf miner adults and their parasitoid species. B. thuringiensis reduced leaf miners as compared to non-treated plots. On the other hand, the highest yield was recorded with the B. thuringiensis treated plots. The results indicate that, B. thuringiensis should be treated only once every 2-3 weeks for effective control of L. trifolii. The percentage of parasitization in the B. thuringiensis non-treated plots were higher than B. thuringiensis treated plots and the percentage of parasitization were 59.14 and 50.69% respectively.
Residual Toxicity of Abamectin, Chlorpyrifos, Cyromazine, Indoxacarb and Spinosad on Liriomyza trifolii (Burgess) (Diptera: Agromyzidae) in Greenhouse Conditions
Ghasem Askari Saryazdi,Mir Jalil Hejazi,Moosa Saber
Pesticidi i Fitomedicina , 2012,
Abstract: Liriomyza trifolii is an important pest of vegetable crops in many parts of the worldincluding Iran. In this study potted bean plants were sprayed with recommended fieldrates of abamectin, chlorpyrifos, cyromazine, indoxacarb and spinosad. To assess the residualactivities of these insecticides, the plants were infested with L. trifolii adults 2 hours; 1, 3,5, 7, 10, 15, 20, 25 and 35 days after insecticidal treatments. The adults were allowed to stayon treated plants for eight hours. The treated plants were kept in a greenhouse. Numberof feeding stipples and larval mines on leaves, as well as pupation and adult eclosion rateswere assessed. Two-way ANOVA procedure of SAS was used for statistical analysis andthe treatment means were separated using Duncan’s multiple range test. Abamectin andspinosad severely affected egg hatching and embryonic development. Eggs oviposited inleaves with residues of chlorpyrifos up to 5 days old, had reduced hatching. Larval developmentwas also, affected by residues of chlorpyrifos up to four weeks old. Indoxacarbreduced larval development and adult eclosion in treatments with up to 20 days old residues.Cyromazine had no effect on the number of larval mines, but, pupation was severelyhampered and adult eclosion was completely ceased even in treatments with five weeksold residues. Determining the residual activity of insecticides used for controlling this pestis useful in avoiding unnecessary treatments.
Scientific Opinion on the risks to plant health posed by Liriomyza huidobrensis (Blanchard) and Liriomyza trifolii (Burgess) in the EU territory, with the identification and evaluation of risk reduction options
EFSA Panel on Plant Health (PLH)
EFSA Journal , 2012, DOI: 10.2903/j.efsa.2012.3028
Abstract: The Panel on Plant Health conducted a pest risk assessment for Liriomyza huidobrensis and Liriomyza trifolii in the European Union and identified and evaluated the phytosanitary measures listed in Council Directive 2000/29/EC. Entry on the principal pathways (plants for planting, cut flowers and leafy vegetables) is assessed as likely as the pests are regularly associated with the pathways at origin, survival during transport or storage is high and only partially affected by current pest management procedures, and transfer to a suitable host is likely as their hosts are so widespread. Establishment is rated as very likely because both species have established populations in most countries of the EU, with transient populations occurring outdoors in non-Mediterranean areas. Spread within the EU is considered to be likely because the pests can readily be moved with plant material. The magnitude of the potential consequences is rated as minor for both species in Mediterranean areas. In non-Mediterranean countries it is moderate for both species in protected crops but, outdoors, impacts are minor for L. huidobrensis and minimal for L. trifolii. The current regulations to prevent entry and spread were found to be only partially effective as interceptions are still being made, cut branches with foliage and leafy vegetables other than celery are excluded, and the methods for inspection and the treatments required to confirm pest free areas, places of production and consignments are not clearly specified. Removal of the legislation would have some advantages and disadvantages but may not have a major effect. The regulations could be tightened by including additional commodities, clearly prescribing the inspection procedures and the appropriate treatments to be used and combining these with other measures, e.g. screening. The application of protected zones to areas where the pests are not yet present can be applied to help prevent further spread.
Ciclo de vida, hábitos y enemigos naturales de Liriomyza sativae blanchard (Diptera: agromyzidae), minador del fríjol  [cached]
Cruz R. Ana M. de la,Cardona J. César,Cruz L. Jaime de la
Acta Agronómica , 1989,
Abstract: El presente estudio se realizó en el Centro Internacional de Agricultura Tropical CIAT, Palmira. Se consideró como objetivo principal el estudio biológico del minador del fríjol liriomyza sativae Blanchard, en condiciones controladas de invernadero y sus enemigos naturales. Se hizo la descripción morfológica de todos los estados de desarrollo del insecto y de los da os ocasionados por el adulto. Igualmente se midió la duración del ciclo de vida en condiciones controladas; temperatura promedia 24-7°C y humedad relativa 64.3%. la duración promedia de los estados de desarrollo fue: huevo, 2.6 días; en conjunto los tres instares larvales, 4.6 días; prepupa, 5 horas y 20 minutos; pupa, 9.1 días; adulto hembra, 19.9 días y adulto macho 13.6 días. El promedio de huevos totales ovipositados por hembra copulada fue 279.3 y por hembra virgen 172.3 huevos. El porcentaje de huevos fértiles por hembra copulada fue 79.4% y el tiempo promedio de ovoposición para hembra copulada fue 16.4 días y para hembra virgen 19.11 días. Los adultos pueden copular varias veces con la misma o diferente pareja. No hay partenogénesis. Se encontraron dos parásitos: Opius sp., un parásito de larvas que emerge de la pupa y Diglypus begini parasitando larvas y un predador de adultos Drapetis Elaphropeza) sp. Entre las plantas cultivadas y silvestres que hospedan al L. sativae se encontraron: hierba mora (Solanum nigrum), sandia (Citrullus lunatus), pepino (Cucumis sativus) y habichuela (Phaseolus vulgaris). This study was carried out at the Centro International de Agricultura Tropical CIAT, Palmira, Colombia. The main purpose was to study biology and natural enemies of the bean leafminer, liriomyza sativae Blanchard, under controlled conditions. Morphological descriptions of the life stages and damage of L. sativae were made. The life cycle was conducted at 24.7°C and 64.3 % relative humidity. Average duration of the eggs was 2.6 days; the three larval instars, 4.6 days; prepupa, five hours and 20 minutes; pupa, 9.1 days; female adult, 19.9 days male adult, 13.6 days. Mated females laid an average of 279.3 eggs with 79.4% of fertility. Virgin females laid an average of 172.3 eggs. Average oviposition time for mated females was 16.4 days and for virgin females was 19.1 days. Adults can mate several times with the same or different pair. There is not parthenogenesis in this species. Two parasites of L. sativae were found: Opius sp, a larval parasite that emerges from the pupa and Diglyphus begini, a larval parasite. A predator of adults, identified as Drapetis (Elaphropeza) sp., was also fo
Pronóstico de la fluctuación poblacional del minador de la hoja de crisantemo Liriomyza huidobrensis blanchard (Diptera: Agromyzidae) mediante modelos de series de tiempo
Acta zoológica mexicana , 2009,
Abstract: El presente trabajo se realizó con el propósito de modelar la fluctuación poblacional del minador de la hoja de crisantemo Liriomyza huidobrensis (Blanchard) a fin de encontrar modelos de predicción con el método de Box & Jenkins que pudieran representar y predecir la densidad de población del insecto en su estado de larva. Se trabajó en dos ciclos de cultivo con duración de cuatro meses cada uno obteniéndose dos poblaciones de insectos. El número de insectos se registró periódicamente cada dos días obteniendo 61 observaciones para cada ciclo de cultivo; por fecha de lectura se anotó el número de larvas vivas; teniendo así dos series de tiempo. Las primeras 55 observaciones de cada serie se analizaron para la obtención del modelo de acuerdo a la metodología de Box & Jenkins y las seis observaciones finales ayudaron a validar la capacidad de predicción del modelo encontrado. En el proceso de identificación del modelo para la representación de cada una de las series observadas se probaron transformaciones de éstas, siendo los ajustes más adecuados para la serie 1 la transformación con raíz cuadrada, y para la serie 2 la transformación de Box-Cox con potencia (0.387455). En ambas series las autocorrelaciones (FAC) denotaron estacionaridad y las autocorrelaciones parciales (FACP) se interrumpieron en la autocorrelación 1. El modelo estimado para la serie 1 fue Yt= 0.246842 + 0.978041 Yt-1 y para la serie 2 fue Yt= 0.283874 + 0.985939 Yt-1. La verificación del modelo ajustó bien los datos al obtener ruido blanco en los residuales de la FAC y FACP de los modelos estimados. Se generaron dos modelos estacionarios de series de tiempo autorregresivos del tipo AR (1) que representaron a las series observadas de L. huidobrensis, ajustandose bien al comportamiento real de sus poblaciones y logrando predecir satisfactoriamente valores de la fluctuación poblacional del insecto.
Pronóstico de la fluctuación poblacional del minador de la hoja de crisantemo Liriomyza huidobrensis Blanchard (Diptera: Agromyzidae), mediante modelos de series de tiempo
Acta zoológica mexicana , 2009,
Abstract: the present study had the objective of modelling population fluctuation of chrysanthemum leaf miner (liriomyza huidobrensis blanchard), using the box & jenkins method, in order to find prediction models, which could represent and adequately predict population density of the insect at its larval stage. the work was carried out in two four-month crop cycles. the number of insects was recorded periodically every two days, resulting in 61 observations for each crop cycle. the number of live larvae was registered by reading date, obtaining two time series. the first 55 observations of each series were analyzed to set the model according to the box & jenkins' method, and the six final observations helped to validate the prediction capacity of the model found. in the process of identifying the model for the representation of each of the observed series, their transformation was tested, finding for series 1 that the transformation with square root had the most adequate fit, and for series 2, the transformation of box-cox with power (0.387455) was the most adequate. in both series, the autocorrelations (fac) showed stationarity, and partial autocorrelations (facp) were interrupted in autocorrelation 1. the estimated model for series 1 was yt=0.246842 + 0.978041 yt-1 , and for series 2, it was yt= 0.283874 + 0.985939 yt-1. the testing of the model fitted the data well, obtaining white noise in the residuals of fac and facp of the estimated models. two stationary models of autoregressive time series of the ar (1) type were generated, representing the observed series of l. huidobrensis, well fitting the true behaviour of their populations and achieving to satisfactorily forecast future values of the insect population fluctuation.
Interspecific competition among three invasive Liriomyza species

XIANG Juncheng,LEI Zhongren,WANG Haihong,GAO Yulin,

生态学报 , 2012,
Abstract: Leafminers (Liriomyza sativae, L. huidobrensis, and L. trifolii) are a group important insect pests of vegetable and ornamental crop production globally. Previous studies indicate that interspecific competition, and species succession and/or displacement are commonly present among different leafminer species. This review herein has reviewed the recent research progresses on interspecific competition among Liriomyza species worldwide with a special focus on Chinese literature. In addition to the review of the fast expanding literature on distribution, biology, ecology, and management of the three leafminer species worldwide, we focused on the interspecific competition and its ramifications in deciphering the possible underlying mechanisms for the competition. The key factors affecting interspecific competition, species succession and/or displacement were identified as reproduction interference, emergence of virulent biotypes, natural enemy suppression, niches of leafminers and their host crops, and pesticide resistance. Although the three invasive species of Liriomyza are the key pest species in China, their distribution patterns vary significantly. While L. sativae is distributed in all provinces in the mainland China, L. huidobrensis is distributed in majority of, but not all provinces, and L. trifolii is currently limited in the southeastern provinces (e.g., Guangdong and Hainan provinces). However, the distribution of L. trifolii is rapidly expanding among the eastern coastal provinces as the result of the development of new virulent biotypes, which is likely to be selected by frequent insecticide applications on the short-cycled vegetable and ornamental crops in the region. The dynamic changes in key ecological factors influencing interspecific competition are valuable in designing innovative management strategies for leafminers in general and to advance our knowledge of understanding ecological genetics, and plasticity of host plant adaptation, and evolution of host speciation of leafminer pest in the confined greenhouse and/or field vegetable and ornamental crop production ecosystems. This review on key ecological research status and prospects on invasive Liriomyza spp., which could be readily used as the guidelines of ecological research on other invasive pest species to identify the key factors related to interspecific competition, and consequently species succession and displacement.
Contributions to the study of Pseudopeziza trifolii (Bernh.) Fuck. fungus
Olga PALL,Ioan BOBES,Despina MUSAT
Notulae Botanicae Horti Agrobotanici Cluj-Napoca , 1966,
Abstract: The present paper communicates the results of the laboratory experiments concerning the behaviour of the Pseudopeziza trifolii (Bernh.) Fuck. fungus that produces the clover brown leaf spot, in different culture mediums. The mycelium of the fungus develops at its best on the peptone-glucose-agar medium. The appearance of pycnides of Sporonema phacidioides Desm. type in vitro, has been reported for the fourth time in Romania especially developing on the potatoe-dextrosis-agar and plum-agar mediums.
Parasitoid Quality of Gronotoma micromorpha Parasitizing Liriomyza huidobrensis on Chinese Cabbage and Soybean  [cached]
HAYATI Journal of Biosciences , 2011,
Abstract: A study with the aim to investigate the quality of Gronotoma micromorpha which attack the immature developmental stages of Liriomyza huidobrensis has been carried out. Such variables as body length measured from caput to the tip of abdomen, wing span and the length of tibia of hind leg were measured to represent parasitoid quality. The immature developmental stage period of the parasitoid was also recorded. The result indicated that a better quality Gronotoma was obtained when it was developed in the Liriomyza larvae fed on chinese cabbage with the average of 123.85 m for body length, 253.45 m for wing span, and 42.85 m for the length of hind tibia, respectively. When Gronotoma was developed in the Liriomyza larvae fed on soy bean, its size became smaller with the average of 97.7 um for body length, 214.3 um for wing span, and 37.2 um for the hind tibia. When it is developed in the Liriomyza on chinese cabbage host plant the immature developmental period of Gronotoma is sligthly shorter with the average of 18.4 and 17.3 days for which developed in the larvae and pupa respectively and on soy bean it become longer with the average of 19.2 days for in eggs, 19.9 days for that in the larvae. On chinese cabbage, Liriomyza tend to have bigger size for both flies and pupae.
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