Se están realizando estudios sobre la función ecológica de los setos naturales mediterráneos como... more Se están realizando estudios sobre la función ecológica de los setos naturales mediterráneos como hábitat de la entomofauna auxiliar asociada a los cítricos ecológicos y convencionales, en parcelas citrícolas valencianas. El trabajo se lleva a cabo sobre setos mixtos compuestos de especies mediterráneas, tales como lentisco, espino blanco, aladierno o cornicabra, y setos monoespecíficos de cipreses, árbol del cielo y granado, recolectando los artrópodos mediante trampas pegajosas amarillas y aspiración (soplador ECHO PB 46-LN + kit aspirador). A su vez, se realiza una comparación con otras parcelas vecinas conducidas con técnicas convencionales y sin seto propio. También se han realizado trabajos de identificación de las especies encontradas en las cubiertas vegetales asociadas a las parcelas ecológicas. Los resultados muestran que los setos estudiados tienen una gran diversidad de fauna auxiliar. Las especies encontradas son muy similares a las encontradas en los cítricos, pero dis...
Transferencia tecnológica Cold pitting en la mandarina "Fortune". Descripción de la alteración y ... more Transferencia tecnológica Cold pitting en la mandarina "Fortune". Descripción de la alteración y control pre:cosecha 'Dpto. Prod. Vegetal.
A study of natural enemies within hedgerows and on ground covers was carried out in two organic c... more A study of natural enemies within hedgerows and on ground covers was carried out in two organic citrus orchards in two areas of Valencia (Spain) using two sampling methods, yellow sticky traps and a vacuum machine. Hedgerows had significantly higher levels of natural enemies, followed by citrus and ground covers. The species of natural enemies in hedgerows were similar to those found in citrus orchards, but different from those identified on ground cover. In hedgerows and citrus the predominant predators were Coniopterygidae (Neuroptera) and Cecidomyiidae (Diptera), and the most abundant parasitoids were Aphelinidae (Hymenoptera).
Predatory insects are key natural enemies that can highly reduce crops pest damage. However, ther... more Predatory insects are key natural enemies that can highly reduce crops pest damage. However, there is a lack of knowledge about the movements of flying predatory insects in agroecosystems throughout the year. In particular, it is still unclear how these predators move from crop to non-crop habitats, which are the preferred habitats to overwinter and to spread during the spring and if these predators leave or stay after chemical treatments. Here, the Neuroptera, a generalist, highly mobile, flying predator order of insects, was selected as model. We studied the effects of farming management and the efficiency of edge shelterbelts, ground cover vegetation, and fruit trees canopy on holding flying predatory insects in Mediterranean traditional agroecosystems. Seasonal movements and winter effects were also assessed. We evaluated monthly nine fruit agroecosystems, six organic, and three pesticides sprayed, of 0.5-1 ha in eastern Spain during 3 years using two complementary methods, yellow sticky traps and aspirator. Results show surprisingly that the insect abundance was highest in pesticide sprayed systems, with 3.40 insects/ sample versus 2.32 insects/sample in organic systems. The biodiversity indices were highest in agroecosystems conducted under organic management, with S of 4.68 and D of 2.34. Shelterbelts showed highest biodiversity indices, S of 3.27 and D of 1.93, among insect habitats. Insect species whose adults were active during the winter preferred fruit trees to spend all year round. However, numerous species moved from fruit trees to shelterbelts to overwinter and dispersed into the orchard during the following spring. The ground cover vegetation showed statistically much lower attractiveness for flying predatory insects than other habitats. Shelterbelts should therefore be the first option in terms of investment in ecological infrastructures enhancing flying predators.
RESUMEN A fin de conocer las causas del incremento que provocan las aplicaciones de deltametrina ... more RESUMEN A fin de conocer las causas del incremento que provocan las aplicaciones de deltametrina en verano en la densidad poblacional del ácaro rojo de frutales Panonychus ulmi Koch, y de forma especial en su puesta invernal, se ha aplicado en una parcela de manzano el citado plaguicida en dos épocas, julio y agosto, siguiéndose la evolución de las poblaciones del ácaro rojo tanto en sus formas móviles sobre las hojas como en sus puestas invernales sobre las ramas, y evaluando asimismo el impacto del plaguicida sobre las poblaciones del fitoseido depredador Amblyseius potentillae. Se ha analizado también la influencia del tratamiento en la fisiología del ácaro fitófago por medio de observaciones en laboratorio. Se ha observado que la aplicación de deltametrina en verano da lugar a un incremento de las poblaciones de la plaga originado por la eliminación de enemigos naturales y por estimulación directa de la fecundidad de las hembras, y aumenta además de forma notable la puesta de hu...
The diaspidid scale Chrysomphalus aonidum was first detected in Valencia in 1999. In 2004, studie... more The diaspidid scale Chrysomphalus aonidum was first detected in Valencia in 1999. In 2004, studies on its biology were initiated due to the importance of the damages caused by this insect in most citrus regions of the world. The objectives of this work were, first, to investigate the distribution and behaviour of C. aonidum in the area of appearance in order to control the pest and prevent its dispersion towards commercial citrus fields. Second, to detect its natural enemies and to determine their relative abundance. C. aonidum monitoring was carried out in 2004 and 2005, locating all the infested citrus trees, starting from the first point of infestation. In two selected groves, periodic samplings were made, consisting of fifteen leaves and some fruits. In the laboratory, individuals of different development stages in the population were counted. In addition, adult males were captured with sexual pheromone traps. Very high levels of this scale were detected. C. aonidum completes fr...
RESUMEN El minador de hojas de cítricos Phyllocnistis citrella apareció por vez primera en España... more RESUMEN El minador de hojas de cítricos Phyllocnistis citrella apareció por vez primera en España en agosto de 1993. En la cuenca mediterránea ha alcanzado todas las zonas de cultivo de cítricos en apenas dos años. La brotación de primavera no es afectada por la plaga que alcanza poblaciones muy elevadas entre julio y septiembre en las sucesivas brotaciones de verano. Muestra preferencia por hacer la puesta en hojas de 1 a 3 cm de longitud y las formas sobre el haz mueren en mucha mayor proporción que las formas en el envés aunque inicialmente los huevos puestos se encuentran en una proporción similar en las dos caras de la hoja. En hojas normales de naranjo de 8 cm de longitud un insecto por hoja destruye aproximadamente el 30% de la superficie foliar y tres el 60%. En árboles plenamente desarrollados la trascendencia sobre la producción puede es escasa y causa daños importantes solo en plantones e injertadas. Varias especies de parasitoides nativos eulófidos que habitualmente atac...
Samples were taken from 30 orange groves between September and November 1995 in the citrus growin... more Samples were taken from 30 orange groves between September and November 1995 in the citrus growing area around Valencia (Spain). Young leaves with citrus leaf miner (CLM) Phyllocnistis citrella Stainton were collected and observed in the laboratory, and shoots were placed in insectaries to obtain parasitoid adults. Every grove had parasitoids and the rate of active parasitism varied greatly, ranging from 10% to 60% without clear relationship with chemical treatments carried out in the grove. Parasitism increases with time as autumn progresses. The five species of parasitoids identified were, in order of abundance, Pnigalio sp., Cirrospilus pictus Nees, Cirrospilus vittatus Walker, Sympiesis gregori Boucek and Chrysocharis sp. Pnigalio sp. predominates in summer, being gradually replaced in autumn by both species of Cirrospilus. Pnigalio parasitizes mostly L4, but also L3 and pupae, and its ratio male:female is nearly 2: 1. Both species of Cirrospilus are parasitoids of L3 and their ...
... Page 2. Castelo Branco ... Pragas das CuFturas na Ilha de S. Miguel. Bolm. da Soc. port. Ent ... more ... Page 2. Castelo Branco ... Pragas das CuFturas na Ilha de S. Miguel. Bolm. da Soc. port. Ent T (Supl. A): 7-33. ... Page 4. ILHARCO, F. A., 1980. Afideos Colhidos nos Asores pelo Major Bivar de Sousa, entre Julho de 1978 e Agosto de 1979 (Homeptera Aphidoidea). Bolm. da Sm. ...
... respectively. Tydeidae (saprophagous) and Cheyletidae (predatory), are represented by only on... more ... respectively. Tydeidae (saprophagous) and Cheyletidae (predatory), are represented by only one species. Phytoseiidae Berlese Amblyseius califarnicas (McGregor) SAO MIGUEL, Rabo de Peixe, 06.July.1993, 1 rn, on orange. A ...
Go to AGRIS search. Phytoma España (Mar 2010). Description, origin and expansion of Tuta absoluta... more Go to AGRIS search. Phytoma España (Mar 2010). Description, origin and expansion of Tuta absoluta (Lepidoptera: Gelechiidae ...
Saissetia oleae (Olivier) (Hemiptera: Coccidae) populations were studied and compared in citrus (... more Saissetia oleae (Olivier) (Hemiptera: Coccidae) populations were studied and compared in citrus (Citrus spp.) and olive (Olea europaea L.) groves to determine the number of generations, crawler emergence periods and changes in population density during the year. Ten citrus and four olive groves were sampled regularly between March 2003 and December 2005 in eastern Spain, covering an area of 10,000 km 2. Each sample consisted of 16 branches and 64 leaves. Saissetia oleae populations presented a similar trend in both crops during the three years of study. Populations peaked in July, when crawlers emerged after the egg-laying period, and decreased during several months due to mortality of Þrst instars in summer. A second crawler emergence period, with lower numbers and more variability from year to year, occurred between October and March. Populations did not increase during this period, probably because most eggs and crawlers perished during the winter and also because females that gave rise to this fall-winter generation were half as big and fecund as spring females. No differences were found between the size of mature females that had developed on citrus and on olives during the spring. Considering this population pattern, the best seasonal period to apply pesticides to control S. oleae would be at the end of July, when populations are synchronous, all crawlers have already emerged, and Þrst instars predominate.
The parasitoid assemblage associated with the citrus leafminer Phyllocnistis citrella Stainton (L... more The parasitoid assemblage associated with the citrus leafminer Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae) was studied in citrus orchards in eastern Spain over a 7-yr period (1995Ð2001) after the leafminerÕs introduction in 1994. In total, 11,587 adult native parasitoids were collected. To evaluate parasitism, 93,846 live immature stages of the citrus leafminer were observed, of which 21,460 (22.9%) were found to be parasitized. The parasitoid complex recruited around P. citrella was typical for invader hosts: lower species richness, generalized habits, idiobiont strategy, and low to moderate rates of parasitism. Two of the 10 species reared from the citrus leafminer, Pnigalio sp. and Cirrospilus brevis Zhu, LaSalle and Huang, accounted for Ͼ90% of the parasitoids. Native parasitoids moved onto the invading host rapidly, except for C. brevis, which required 3 yr to become common and widespread. In other leafminer species from plants in the vicinity of citrus orchards, the proportion of P. citrella parasitoids was higher in woody (69.7%) than in herbaceous plants (22.2%). The high population levels reached by the new pest, associated with a negative density dependence response of the parasitoids at these high population levels, suggest that the native parasitoid assemblage exerted only a limited role in regulating the population of the new host.
Se están realizando estudios sobre la función ecológica de los setos naturales mediterráneos como... more Se están realizando estudios sobre la función ecológica de los setos naturales mediterráneos como hábitat de la entomofauna auxiliar asociada a los cítricos ecológicos y convencionales, en parcelas citrícolas valencianas. El trabajo se lleva a cabo sobre setos mixtos compuestos de especies mediterráneas, tales como lentisco, espino blanco, aladierno o cornicabra, y setos monoespecíficos de cipreses, árbol del cielo y granado, recolectando los artrópodos mediante trampas pegajosas amarillas y aspiración (soplador ECHO PB 46-LN + kit aspirador). A su vez, se realiza una comparación con otras parcelas vecinas conducidas con técnicas convencionales y sin seto propio. También se han realizado trabajos de identificación de las especies encontradas en las cubiertas vegetales asociadas a las parcelas ecológicas. Los resultados muestran que los setos estudiados tienen una gran diversidad de fauna auxiliar. Las especies encontradas son muy similares a las encontradas en los cítricos, pero dis...
Transferencia tecnológica Cold pitting en la mandarina "Fortune". Descripción de la alteración y ... more Transferencia tecnológica Cold pitting en la mandarina "Fortune". Descripción de la alteración y control pre:cosecha 'Dpto. Prod. Vegetal.
A study of natural enemies within hedgerows and on ground covers was carried out in two organic c... more A study of natural enemies within hedgerows and on ground covers was carried out in two organic citrus orchards in two areas of Valencia (Spain) using two sampling methods, yellow sticky traps and a vacuum machine. Hedgerows had significantly higher levels of natural enemies, followed by citrus and ground covers. The species of natural enemies in hedgerows were similar to those found in citrus orchards, but different from those identified on ground cover. In hedgerows and citrus the predominant predators were Coniopterygidae (Neuroptera) and Cecidomyiidae (Diptera), and the most abundant parasitoids were Aphelinidae (Hymenoptera).
Predatory insects are key natural enemies that can highly reduce crops pest damage. However, ther... more Predatory insects are key natural enemies that can highly reduce crops pest damage. However, there is a lack of knowledge about the movements of flying predatory insects in agroecosystems throughout the year. In particular, it is still unclear how these predators move from crop to non-crop habitats, which are the preferred habitats to overwinter and to spread during the spring and if these predators leave or stay after chemical treatments. Here, the Neuroptera, a generalist, highly mobile, flying predator order of insects, was selected as model. We studied the effects of farming management and the efficiency of edge shelterbelts, ground cover vegetation, and fruit trees canopy on holding flying predatory insects in Mediterranean traditional agroecosystems. Seasonal movements and winter effects were also assessed. We evaluated monthly nine fruit agroecosystems, six organic, and three pesticides sprayed, of 0.5-1 ha in eastern Spain during 3 years using two complementary methods, yellow sticky traps and aspirator. Results show surprisingly that the insect abundance was highest in pesticide sprayed systems, with 3.40 insects/ sample versus 2.32 insects/sample in organic systems. The biodiversity indices were highest in agroecosystems conducted under organic management, with S of 4.68 and D of 2.34. Shelterbelts showed highest biodiversity indices, S of 3.27 and D of 1.93, among insect habitats. Insect species whose adults were active during the winter preferred fruit trees to spend all year round. However, numerous species moved from fruit trees to shelterbelts to overwinter and dispersed into the orchard during the following spring. The ground cover vegetation showed statistically much lower attractiveness for flying predatory insects than other habitats. Shelterbelts should therefore be the first option in terms of investment in ecological infrastructures enhancing flying predators.
RESUMEN A fin de conocer las causas del incremento que provocan las aplicaciones de deltametrina ... more RESUMEN A fin de conocer las causas del incremento que provocan las aplicaciones de deltametrina en verano en la densidad poblacional del ácaro rojo de frutales Panonychus ulmi Koch, y de forma especial en su puesta invernal, se ha aplicado en una parcela de manzano el citado plaguicida en dos épocas, julio y agosto, siguiéndose la evolución de las poblaciones del ácaro rojo tanto en sus formas móviles sobre las hojas como en sus puestas invernales sobre las ramas, y evaluando asimismo el impacto del plaguicida sobre las poblaciones del fitoseido depredador Amblyseius potentillae. Se ha analizado también la influencia del tratamiento en la fisiología del ácaro fitófago por medio de observaciones en laboratorio. Se ha observado que la aplicación de deltametrina en verano da lugar a un incremento de las poblaciones de la plaga originado por la eliminación de enemigos naturales y por estimulación directa de la fecundidad de las hembras, y aumenta además de forma notable la puesta de hu...
The diaspidid scale Chrysomphalus aonidum was first detected in Valencia in 1999. In 2004, studie... more The diaspidid scale Chrysomphalus aonidum was first detected in Valencia in 1999. In 2004, studies on its biology were initiated due to the importance of the damages caused by this insect in most citrus regions of the world. The objectives of this work were, first, to investigate the distribution and behaviour of C. aonidum in the area of appearance in order to control the pest and prevent its dispersion towards commercial citrus fields. Second, to detect its natural enemies and to determine their relative abundance. C. aonidum monitoring was carried out in 2004 and 2005, locating all the infested citrus trees, starting from the first point of infestation. In two selected groves, periodic samplings were made, consisting of fifteen leaves and some fruits. In the laboratory, individuals of different development stages in the population were counted. In addition, adult males were captured with sexual pheromone traps. Very high levels of this scale were detected. C. aonidum completes fr...
RESUMEN El minador de hojas de cítricos Phyllocnistis citrella apareció por vez primera en España... more RESUMEN El minador de hojas de cítricos Phyllocnistis citrella apareció por vez primera en España en agosto de 1993. En la cuenca mediterránea ha alcanzado todas las zonas de cultivo de cítricos en apenas dos años. La brotación de primavera no es afectada por la plaga que alcanza poblaciones muy elevadas entre julio y septiembre en las sucesivas brotaciones de verano. Muestra preferencia por hacer la puesta en hojas de 1 a 3 cm de longitud y las formas sobre el haz mueren en mucha mayor proporción que las formas en el envés aunque inicialmente los huevos puestos se encuentran en una proporción similar en las dos caras de la hoja. En hojas normales de naranjo de 8 cm de longitud un insecto por hoja destruye aproximadamente el 30% de la superficie foliar y tres el 60%. En árboles plenamente desarrollados la trascendencia sobre la producción puede es escasa y causa daños importantes solo en plantones e injertadas. Varias especies de parasitoides nativos eulófidos que habitualmente atac...
Samples were taken from 30 orange groves between September and November 1995 in the citrus growin... more Samples were taken from 30 orange groves between September and November 1995 in the citrus growing area around Valencia (Spain). Young leaves with citrus leaf miner (CLM) Phyllocnistis citrella Stainton were collected and observed in the laboratory, and shoots were placed in insectaries to obtain parasitoid adults. Every grove had parasitoids and the rate of active parasitism varied greatly, ranging from 10% to 60% without clear relationship with chemical treatments carried out in the grove. Parasitism increases with time as autumn progresses. The five species of parasitoids identified were, in order of abundance, Pnigalio sp., Cirrospilus pictus Nees, Cirrospilus vittatus Walker, Sympiesis gregori Boucek and Chrysocharis sp. Pnigalio sp. predominates in summer, being gradually replaced in autumn by both species of Cirrospilus. Pnigalio parasitizes mostly L4, but also L3 and pupae, and its ratio male:female is nearly 2: 1. Both species of Cirrospilus are parasitoids of L3 and their ...
... Page 2. Castelo Branco ... Pragas das CuFturas na Ilha de S. Miguel. Bolm. da Soc. port. Ent ... more ... Page 2. Castelo Branco ... Pragas das CuFturas na Ilha de S. Miguel. Bolm. da Soc. port. Ent T (Supl. A): 7-33. ... Page 4. ILHARCO, F. A., 1980. Afideos Colhidos nos Asores pelo Major Bivar de Sousa, entre Julho de 1978 e Agosto de 1979 (Homeptera Aphidoidea). Bolm. da Sm. ...
... respectively. Tydeidae (saprophagous) and Cheyletidae (predatory), are represented by only on... more ... respectively. Tydeidae (saprophagous) and Cheyletidae (predatory), are represented by only one species. Phytoseiidae Berlese Amblyseius califarnicas (McGregor) SAO MIGUEL, Rabo de Peixe, 06.July.1993, 1 rn, on orange. A ...
Go to AGRIS search. Phytoma España (Mar 2010). Description, origin and expansion of Tuta absoluta... more Go to AGRIS search. Phytoma España (Mar 2010). Description, origin and expansion of Tuta absoluta (Lepidoptera: Gelechiidae ...
Saissetia oleae (Olivier) (Hemiptera: Coccidae) populations were studied and compared in citrus (... more Saissetia oleae (Olivier) (Hemiptera: Coccidae) populations were studied and compared in citrus (Citrus spp.) and olive (Olea europaea L.) groves to determine the number of generations, crawler emergence periods and changes in population density during the year. Ten citrus and four olive groves were sampled regularly between March 2003 and December 2005 in eastern Spain, covering an area of 10,000 km 2. Each sample consisted of 16 branches and 64 leaves. Saissetia oleae populations presented a similar trend in both crops during the three years of study. Populations peaked in July, when crawlers emerged after the egg-laying period, and decreased during several months due to mortality of Þrst instars in summer. A second crawler emergence period, with lower numbers and more variability from year to year, occurred between October and March. Populations did not increase during this period, probably because most eggs and crawlers perished during the winter and also because females that gave rise to this fall-winter generation were half as big and fecund as spring females. No differences were found between the size of mature females that had developed on citrus and on olives during the spring. Considering this population pattern, the best seasonal period to apply pesticides to control S. oleae would be at the end of July, when populations are synchronous, all crawlers have already emerged, and Þrst instars predominate.
The parasitoid assemblage associated with the citrus leafminer Phyllocnistis citrella Stainton (L... more The parasitoid assemblage associated with the citrus leafminer Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae) was studied in citrus orchards in eastern Spain over a 7-yr period (1995Ð2001) after the leafminerÕs introduction in 1994. In total, 11,587 adult native parasitoids were collected. To evaluate parasitism, 93,846 live immature stages of the citrus leafminer were observed, of which 21,460 (22.9%) were found to be parasitized. The parasitoid complex recruited around P. citrella was typical for invader hosts: lower species richness, generalized habits, idiobiont strategy, and low to moderate rates of parasitism. Two of the 10 species reared from the citrus leafminer, Pnigalio sp. and Cirrospilus brevis Zhu, LaSalle and Huang, accounted for Ͼ90% of the parasitoids. Native parasitoids moved onto the invading host rapidly, except for C. brevis, which required 3 yr to become common and widespread. In other leafminer species from plants in the vicinity of citrus orchards, the proportion of P. citrella parasitoids was higher in woody (69.7%) than in herbaceous plants (22.2%). The high population levels reached by the new pest, associated with a negative density dependence response of the parasitoids at these high population levels, suggest that the native parasitoid assemblage exerted only a limited role in regulating the population of the new host.
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