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Alberto J. Alaniz - One of the best experts on this subject based on the ideXlab platform.
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Urbanization filters Coccinellids composition and functional trait distributions in greenspaces across greater Santiago, Chile
Urban Forestry & Urban Greening, 2019Co-Authors: Audrey A. Grez, Mary M. Gardiner, Tania Zaviezo, Alberto J. AlanizAbstract:Abstract Urbanization alters community composition, frequently leading to decline in native species abundance and richness. Nevertheless, responses might also depend on trait-based local habitat and landscape-scale filters. In this work, we studied how local characteristics of greenspaces and landscape context at 100 and 1000 m influence taxonomic and functional traits composition of native and alien Coccinellids (Coleoptera: Coccinellidae) across an urbanization gradient extending from the city of Santiago, Chile, into surrounding rural areas. We found that greenspaces supported a rich community of Coccinellids, including many native species, but both native and alien species were negatively affected by urbanization. Local habitat variables were not important predictors of Coccinellids richness, abundance or functional traits. On the other hand, landscape composition at both scales did affect coccinellid communities in greenspaces. At both landscape scales, there was variation in the association of Coccinellids with landscape variables based on their primary diet, thus, urbanization might differentially affect the ecological service provided by different functional groups of Coccinellids. Our results show that greenspaces support a rich community of Coccinellids, including many native species, but the degree to which greenspaces conserve these communities depends on the level of urbanization.
António J.a. Nogueira - One of the best experts on this subject based on the ideXlab platform.
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Response of coccinellid community to the dimethoate application in olive groves in Northeastern Portugal
Spanish Journal of Agricultural Research, 2010Co-Authors: Sónia A.p. Santos, José Alberto Pereira, Laura Torres, A. Raimundo, António J.a. NogueiraAbstract:In this work we assessed the effects of the application of dimethoate on the coccinellid community. The field work was carried out on a weekly basis, in two different olive groves, from April to November of 2002 and 2003 and captured Coccinellids were identified to species level. Principal response curves (PRC) method was used to analyse the effect of the dimethoate application on the abundance of coccinellid species. A total of 23 species were identified from the two olive groves. Nine species occurred in both olive groves and in the two years of the study. Scymnus interruptus was the dominant species in the control grove with 46.4% of the total Coccinellidae recovered while in the grove treated with dimethoate, Rhyzobius chrysomeloides represented 35.7% of the total number captured. PCR showed that the main effect of the treatment was a significant reduction of the abundance of the most common species of the coccinellid community (S. interruptus and Chilocorus bipustulatus) in the treated grove. This can also have implications on the preservation of ecological functions associated with Coccinellids, namely their role as control agents of olive pests. Additional key words: Coccinellidae, integrated pest management, Olea europaea, organic farming, principal response curves, species abundance.
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Seasonal synchrony between Saissetia oleae and coccinellid species in Portuguese olive groves in different management systems
Bulletin of Insectology, 2010Co-Authors: Sónia A.p. Santos, José Alberto Pereira, Laura Torres, A. Raimundo, António J.a. NogueiraAbstract:Abstract Go The black scate, Saisselia oh.!ae (Olivier) (Hemiptera Coccicbe), is one of (he main oli ve pests and Coccinellids are among lht! principal predators that feed on scalc!). The relationships betwecn the tcmpor~!l abundance of live common coccinellid species [Chi/ocarus biplf.WII/alWi l., S('ylllll/l~; .'IIIbvi//O .\'IIS (Goeze). SCylllllll.l" medilerrallellS iablokoff·KJlIlzorian, SCylllllllS illlerrupllls (Goeze). Nhy::obills cllI~vsumdoide::i (Herbst)] and the difrerent phenological stnges of S. olene were investigated in two oli ve groves managed under two different systems (Integrated Pesl Management and Organic Farming) during 2002 and 2003. Coc· cincllids and black scale wert: randomly sampled on a fortnightly basis and correlation analyses between the abundance of th e coccinellid species and the difTeren t stages urthe pest were carried out. Results showed that the abundnnce ofS. o/eae was similar between olive groves and YC.Jrs. However, significant differences were J"ound fo r adult and larvae of coecinellid species. [n both years and groves. the greatest abundance of Coccinellids occurred between June and November. also corresponding to the peri od of greatest abundance of the fi rst and second instal' nymphs of S v/eae. Signilicant positive correlations were obtained between the second insrar nymph and four out of tive l.:Occ inel!id species, being potential[ y the most predated stage of the pest. On th e con· trary. no significant positive correlarions were found between the third instal' nymph and the coccinellid species.
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Voracity of coccinellid species on different phenological stages of the olive pest Saissetia oleae (Homoptera, Coccidae).
Applied Ecology and Environmental Research, 2009Co-Authors: Sónia A.p. Santos, José Alberto Pereira, Laura Torres, António J.a. NogueiraAbstract:Coccinellidae are well known predators in agroecosystems. In olive groves they may exert control against scales, such as the black scale, Saissetia oleae (Olivier, 1791). Laboratory studies on the consumption of three phenological stages (eggs, first and second instar nymphs) of S. oleae by four coccinellid species ( Chilocorus bipustulatus , Scymnus (Pullus) subvillosus , Scymnus (Mimopullus) mediterraneus and Scymnus (Scymnus) interruptus ) were carried out. C. bipustulatus presented a significantly high consumption of eggs, first and second instar nymphs compared with the other species. All Coccinellids consumed eggs and first instar nymphs; however the second instar nymphs were only consumed by S. interruptus and C. bipustulatus . In a second experiment, larval stages of C. bipustulatus were reared on different phenological stages of S. oleae . Coccinellid larvae fed with eggs or first instar nymphs completed their life cycle, contrarily to those that were fed with second instar nymphs. The apparent voracity of C. bipustulatus on the different phenological stages of S. oleae is an aspect that suggests the possible use of this coccinellid species in biological control programs against this pest in
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Identification of predator–prey relationships between Coccinellids and Saissetia oleae (Hemiptera: Coccidae), in olive groves, using an enzyme-linked immunosorbent assay
Journal of Pest Science, 2009Co-Authors: Sónia A.p. Santos, José A. Pereira, Maria Conceição Rodrigues, Laura M. Torres, Ana Maria N. Pereira, António J.a. NogueiraAbstract:A polyclonal antiserum (AS) was developed and characterized for the detection of immature stages of the black-scale, Saissetia oleae , in whole body homogenized field-collected coccinellid species, using an indirect enzyme-linked immunosorbent assay (ELISA). The indirect ELISA showed to be sensitive to the S. oleae AS, detecting a protein content between 0.118 and 0.0374 μg mL^−1. The specificity of the ELISA was tested by assaying a range of sympatric predators and alternative preys with the S. oleae AS. Coccinellid larvae obtained the highest cross-reaction and a positive–negative threshold was established at 0.674 μg mL^−1 protein. A total of 1,322 Coccinellids were field-collected in three olive groves located in Trás-os-Montes (northeast of Portugal) by the beating technique and were analyzed to detect S. oleae proteins in their guts. Field-collected Coccinellids which attained a S. oleae protein concentration equivalent higher than the threshold were considered as a positive reaction. In the overall collected Coccinellids, 21.2% reacted positively with the S. oleae AS. Chilocorus bipustulatus and coccinellid larvae obtained the highest percentages of positives with 43.4 and 40.8%, respectively. The greatest frequency of positive responses occurred at the beginning of July, mid-August, and mid-October coinciding with the occurrence of the first, second and third instar nymphs of S. oleae , respectively. Thus, in this study, the role of Coccinellids as natural control agents of S. oleae was highlighted by the number of individuals and species that tested positive for S. oleae AS.
Douglas A Landis - One of the best experts on this subject based on the ideXlab platform.
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The role of exotic ladybeetles in the decline of native ladybeetle populations: evidence from long-term monitoring
Biological Invasions, 2015Co-Authors: Christine A. Bahlai, Manuel Colunga-garcia, Stuart H. Gage, Douglas A LandisAbstract:Ladybeetles (Coleoptera: Coccinellidae) are ubiquitous predators which play an important role in suppressing pest insects. In North America, the coccinellid community is increasingly dominated by exotic species, and the abundance of some native species has declined dramatically since the 1980s. Several hypotheses have been proposed to describe the mechanism of invasion coupled with native species declines, e.g. vacant niche exploitation, intraguild predation, competitive exploitation and habitat compression. We analyze a 24-year dataset of coccinellid community structure in southwestern Michigan to elucidate the most likely mechanism(s) of native coccinellid decline and implications for their conservation. Correlation analyses indicated that impact of exotic species on native Coccinellids varies with their degree of interaction. Although several native species were observed to be in numerical decline, only Adalia bipunctata and Coleomegilla maculata had declines that were statistically significant. The magnitude of decline in these two species varied with the degree of dietary overlap with invaders, thus their decline is most likely driven by competitive exploitation. Habitat use patterns by some native species ( A. bipunctata and Coccinella trifasciata ) changed during years when the exotic Harmonia axyridis reached high numbers, lending support to the habitat compression hypothesis, where native species survive in ancestral (i.e. natural or semi-natural) habitats when invaders dominate cultivated habitats. Coccinellid communities occurring in semi-natural forested habitats were unique in both composition and variability from those occurring in cultivated habitats. Such semi-natural habitats can act as refuges for native Coccinellids and may play a role in maintaining the functional resilience of coccinellid communities.
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Long-term functional dynamics of an aphidophagous coccinellid community remain unchanged despite repeated invasions.
PloS one, 2013Co-Authors: Christine A. Bahlai, Manuel Colunga-garcia, Stuart H. Gage, Douglas A LandisAbstract:Aphidophagous Coccinellids (ladybeetles) are important providers of herbivore suppression ecosystem services. In the last 30 years, the invasion of exotic coccinellid species, coupled with observed declines in native species, has led to considerable interest in the community dynamics and ecosystem function of this guild. Here we examined a 24-year dataset of coccinellid communities in nine habitats in southwestern Michigan for changes in community function in response to invasion. Specifically we analyzed their temporal population dynamics and species diversity, and we modeled the community’s potential to suppress pests. Abundance of Coccinellids varied widely between 1989 and 2012 and became increasingly exotic-dominated. More than 71% of 57,813 adult Coccinellids captured over the 24-year study were exotic species. Shannon diversity increased slightly over time, but herbivore suppression potential of the community remained roughly constant over the course of the study. However, both Shannon diversity and herbivore suppression potential due to native species declined over time in all habitats. The relationship between Shannon diversity and herbivore suppression potential varied with habitat type: a positive relationship in forest and perennial habitats, but was uncorrelated in annual habitats. This trend may have been because annual habitats were dominated by a few, highly voracious exotic species. Our results indicated that although the composition of the coccinellid community in southwestern Michigan has changed dramatically in the past several decades, its function has remained relatively unchanged in both agricultural and natural habitats. While this is encouraging from the perspective of pest management, it should be noted that losses of one of the dominant exotic Coccinellids could result in a rapid decline in pest suppression services if the remaining community is unable to respond.
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Coccinellid immigration to infested host patches influences suppression of Aphis glycines in soybean
Biological Control, 2013Co-Authors: J. Megan Woltz, Douglas A LandisAbstract:Abstract Generalist natural enemies may be well adapted to annual crop systems in which pests and natural enemies re-colonize fields each year. In addition, for patchily-distributed pests, a natural enemy must disperse within a crop field to arrive at infested host patches. As they typically have longer generation times than their prey, theory suggests that generalist natural enemies need high immigration rates to and within fields to effectively suppress pest populations. The soybean aphid, Aphis glycines Matsumura, is a pest of an annual crop and is predominantly controlled by Coccinellids. To test if rates of coccinellid arrival at aphid-infested patches are crucial for soybean aphid control, we experimentally varied coccinellid immigration to 1 m2 soybean patches using selective barriers and measured effects on A. glycines populations. In a year with low ambient aphid pressure, naturally-occurring levels of coccinellid immigration to host patches were sufficient to suppress aphid populations, while decreasing coccinellid immigration rates resulted in large increases in soybean aphid populations within infested patches. Activity of other predators was low in this year, suggesting that most of the differences in aphid population growth were due to changes in coccinellid immigration. Alternatively, in a year in which alate aphids continually colonized plots, aphid suppression was incomplete and increased activity of other predatory taxa contributed to adult coccinellid predation of A. glycines. Our results suggest that in a system in which natural enemy populations cannot track pest populations through reproduction, immigration of natural enemies to infested patches can compensate and result in pest control.
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the role of natural enemy guilds in aphis glycines suppression
Biological Control, 2008Co-Authors: Alejandro C Costamagna, Douglas A Landis, Michael J BrewerAbstract:Generalist natural enemy guilds are increasingly recognized as important sources of mortality for invasive agricultural pests. However, the net contribution of different species to pest suppression is conditioned by their biology and interspecific interactions. The soybean aphid, Aphis glycines (Hemiptera: Aphididae), is widely attacked by generalist predators, but the relative impacts of different natural enemy guilds remains poorly understood. Moreover, low levels of A. glycines parasitism suggest that resident parasitoids may be limited through intraguild predation. During 2004 and 2005, we conducted field experiments to test the impact of different guilds of natural enemies on A. glycines. We contrasted aphid abundance on field cages with ambient levels of small predators (primarily Orius insidiosus) and parasitoids (primarily Braconidae), sham cages and open controls exposed to large predators (primarily Coccinellids), and cages excluding all natural enemies. We observed strong aphid suppression (86- to 36-fold reduction) in treatments exposed to Coccinellids, but only minor reduction due to small predators and parasitoids, with aphids reaching rapidly economic injury levels when Coccinellids were excluded. Three species of resident parasitoids were found attacking A. glycines at very low levels (<1% parasitism), with no evidence that intraguild predation by Coccinellids attenuated parasitoid impacts. At the plant level, coccinellid impacts resulted in a trophic cascade that restored soybean biomass and yield, whereas small natural enemies provided only minor protection against yield loss. Our results indicate that within the assemblage of A. glycines natural enemies in Michigan, Coccinellids are critical to maintain aphids below economic injury levels.
Audrey A. Grez - One of the best experts on this subject based on the ideXlab platform.
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Urbanization filters Coccinellids composition and functional trait distributions in greenspaces across greater Santiago, Chile
Urban Forestry & Urban Greening, 2019Co-Authors: Audrey A. Grez, Mary M. Gardiner, Tania Zaviezo, Alberto J. AlanizAbstract:Abstract Urbanization alters community composition, frequently leading to decline in native species abundance and richness. Nevertheless, responses might also depend on trait-based local habitat and landscape-scale filters. In this work, we studied how local characteristics of greenspaces and landscape context at 100 and 1000 m influence taxonomic and functional traits composition of native and alien Coccinellids (Coleoptera: Coccinellidae) across an urbanization gradient extending from the city of Santiago, Chile, into surrounding rural areas. We found that greenspaces supported a rich community of Coccinellids, including many native species, but both native and alien species were negatively affected by urbanization. Local habitat variables were not important predictors of Coccinellids richness, abundance or functional traits. On the other hand, landscape composition at both scales did affect coccinellid communities in greenspaces. At both landscape scales, there was variation in the association of Coccinellids with landscape variables based on their primary diet, thus, urbanization might differentially affect the ecological service provided by different functional groups of Coccinellids. Our results show that greenspaces support a rich community of Coccinellids, including many native species, but the degree to which greenspaces conserve these communities depends on the level of urbanization.
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The heterogeneity and composition of agricultural landscapes influence native and exotic Coccinellids in alfalfa fields
Agricultural and Forest Entomology, 2014Co-Authors: Audrey A. Grez, Tania Zaviezo, Jaime Hernández, Annia Rodríguez-san Pedro, Paz AcuñaAbstract:The current trend toward simplification of agricultural landscapes, as well as the associated loss of perennial cover types, can decrease landscape heterogeneity and also natural enemy abundance and diversity, favouring exotic species. We evaluated the effects of agricultural landscape composition and heterogeneity at two different spatial scales (radii of 250 and 1000 m), on the diversity and abundance of native and exotic Coccinellids, associated with alfalfa fields located in two regions of Central Chile. Data were analyzed using partial least square regressions, considering the whole coccinellid assemblage and the three most abundant species. In both regions, coccinellid diversity and the abundance and proportion of native Coccinellids in alfalfa responded differentially from total abundance and the abundance of exotic Coccinellids. The diversity and abundance of Coccinellids in alfalfa increased with the compositional and configurational heterogeneity of the landscape. The abundance of both native and exotic Coccinellids in alfalfa fields decreased as the area covered by cultivated lands, such as annual crops and orchards, increased. Nevertheless, the responses of native and exotic Coccinellids were not consistent among regions, which may be explained by responses of the dominant species in each region. The results of the present study suggest that variables related to a higher intensification of agricultural landscapes (lower compositional and configurational heterogeneity, as well as more annual crops) reduce coccinellid diversity and abundance in alfalfa fields. To maintain a higher abundance and diversity of these natural enemies in alfalfa, more heterogeneous landscapes with less annual crops should be promoted.
Sónia A.p. Santos - One of the best experts on this subject based on the ideXlab platform.
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Response of coccinellid community to the dimethoate application in olive groves in Northeastern Portugal
Spanish Journal of Agricultural Research, 2010Co-Authors: Sónia A.p. Santos, José Alberto Pereira, Laura Torres, A. Raimundo, António J.a. NogueiraAbstract:In this work we assessed the effects of the application of dimethoate on the coccinellid community. The field work was carried out on a weekly basis, in two different olive groves, from April to November of 2002 and 2003 and captured Coccinellids were identified to species level. Principal response curves (PRC) method was used to analyse the effect of the dimethoate application on the abundance of coccinellid species. A total of 23 species were identified from the two olive groves. Nine species occurred in both olive groves and in the two years of the study. Scymnus interruptus was the dominant species in the control grove with 46.4% of the total Coccinellidae recovered while in the grove treated with dimethoate, Rhyzobius chrysomeloides represented 35.7% of the total number captured. PCR showed that the main effect of the treatment was a significant reduction of the abundance of the most common species of the coccinellid community (S. interruptus and Chilocorus bipustulatus) in the treated grove. This can also have implications on the preservation of ecological functions associated with Coccinellids, namely their role as control agents of olive pests. Additional key words: Coccinellidae, integrated pest management, Olea europaea, organic farming, principal response curves, species abundance.
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Seasonal synchrony between Saissetia oleae and coccinellid species in Portuguese olive groves in different management systems
Bulletin of Insectology, 2010Co-Authors: Sónia A.p. Santos, José Alberto Pereira, Laura Torres, A. Raimundo, António J.a. NogueiraAbstract:Abstract Go The black scate, Saisselia oh.!ae (Olivier) (Hemiptera Coccicbe), is one of (he main oli ve pests and Coccinellids are among lht! principal predators that feed on scalc!). The relationships betwecn the tcmpor~!l abundance of live common coccinellid species [Chi/ocarus biplf.WII/alWi l., S('ylllll/l~; .'IIIbvi//O .\'IIS (Goeze). SCylllllll.l" medilerrallellS iablokoff·KJlIlzorian, SCylllllllS illlerrupllls (Goeze). Nhy::obills cllI~vsumdoide::i (Herbst)] and the difrerent phenological stnges of S. olene were investigated in two oli ve groves managed under two different systems (Integrated Pesl Management and Organic Farming) during 2002 and 2003. Coc· cincllids and black scale wert: randomly sampled on a fortnightly basis and correlation analyses between the abundance of th e coccinellid species and the difTeren t stages urthe pest were carried out. Results showed that the abundnnce ofS. o/eae was similar between olive groves and YC.Jrs. However, significant differences were J"ound fo r adult and larvae of coecinellid species. [n both years and groves. the greatest abundance of Coccinellids occurred between June and November. also corresponding to the peri od of greatest abundance of the fi rst and second instal' nymphs of S v/eae. Signilicant positive correlations were obtained between the second insrar nymph and four out of tive l.:Occ inel!id species, being potential[ y the most predated stage of the pest. On th e con· trary. no significant positive correlarions were found between the third instal' nymph and the coccinellid species.
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Voracity of coccinellid species on different phenological stages of the olive pest Saissetia oleae (Homoptera, Coccidae).
Applied Ecology and Environmental Research, 2009Co-Authors: Sónia A.p. Santos, José Alberto Pereira, Laura Torres, António J.a. NogueiraAbstract:Coccinellidae are well known predators in agroecosystems. In olive groves they may exert control against scales, such as the black scale, Saissetia oleae (Olivier, 1791). Laboratory studies on the consumption of three phenological stages (eggs, first and second instar nymphs) of S. oleae by four coccinellid species ( Chilocorus bipustulatus , Scymnus (Pullus) subvillosus , Scymnus (Mimopullus) mediterraneus and Scymnus (Scymnus) interruptus ) were carried out. C. bipustulatus presented a significantly high consumption of eggs, first and second instar nymphs compared with the other species. All Coccinellids consumed eggs and first instar nymphs; however the second instar nymphs were only consumed by S. interruptus and C. bipustulatus . In a second experiment, larval stages of C. bipustulatus were reared on different phenological stages of S. oleae . Coccinellid larvae fed with eggs or first instar nymphs completed their life cycle, contrarily to those that were fed with second instar nymphs. The apparent voracity of C. bipustulatus on the different phenological stages of S. oleae is an aspect that suggests the possible use of this coccinellid species in biological control programs against this pest in
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Identification of predator–prey relationships between Coccinellids and Saissetia oleae (Hemiptera: Coccidae), in olive groves, using an enzyme-linked immunosorbent assay
Journal of Pest Science, 2009Co-Authors: Sónia A.p. Santos, José A. Pereira, Maria Conceição Rodrigues, Laura M. Torres, Ana Maria N. Pereira, António J.a. NogueiraAbstract:A polyclonal antiserum (AS) was developed and characterized for the detection of immature stages of the black-scale, Saissetia oleae , in whole body homogenized field-collected coccinellid species, using an indirect enzyme-linked immunosorbent assay (ELISA). The indirect ELISA showed to be sensitive to the S. oleae AS, detecting a protein content between 0.118 and 0.0374 μg mL^−1. The specificity of the ELISA was tested by assaying a range of sympatric predators and alternative preys with the S. oleae AS. Coccinellid larvae obtained the highest cross-reaction and a positive–negative threshold was established at 0.674 μg mL^−1 protein. A total of 1,322 Coccinellids were field-collected in three olive groves located in Trás-os-Montes (northeast of Portugal) by the beating technique and were analyzed to detect S. oleae proteins in their guts. Field-collected Coccinellids which attained a S. oleae protein concentration equivalent higher than the threshold were considered as a positive reaction. In the overall collected Coccinellids, 21.2% reacted positively with the S. oleae AS. Chilocorus bipustulatus and coccinellid larvae obtained the highest percentages of positives with 43.4 and 40.8%, respectively. The greatest frequency of positive responses occurred at the beginning of July, mid-August, and mid-October coinciding with the occurrence of the first, second and third instar nymphs of S. oleae , respectively. Thus, in this study, the role of Coccinellids as natural control agents of S. oleae was highlighted by the number of individuals and species that tested positive for S. oleae AS.