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See detailDo flower mixtures with high functional diversity enhance aphid predators in wildflower strips?
Hatt, Séverin ULg; Uyttenbroeck, Roel ULg; Chevalier Mendes Lopes, Thomas ULg et al

in European Journal of Entomology (2017), 114

Among semi-natural elements in agricultural landscapes, wildflower strips sown at field margins or within fields represent potential habitats for the natural enemies of insect pests. As insects are ... [more ▼]

Among semi-natural elements in agricultural landscapes, wildflower strips sown at field margins or within fields represent potential habitats for the natural enemies of insect pests. As insects are sensitive to a variety of flower traits, we hypothesised that mixtures with high functional diversity attract and support a higher abundance and species richness of aphid flower visiting predators compared to mixtures with low functional diversity. During a field experiment, repeated over two years (2014 and 2015) in Gembloux (Belgium), aphid predators (i.e., lacewings, ladybeetles and hoverflies) were pan-trapped in five sown flower mixtures (including a control mixture, with three replicates of each mixture) of low to high functional diversity based on seven traits (i.e., flower colour, ultra-violet reflectance and pattern, blooming start and duration, height and flower class, primarily based on corolla morphology). In both years, flower species in the sown mixtures (i.e., sown and spontaneous flowers) were listed, and the realised functional diversity of each plot was calculated. Over the two years, an increase in functional diversity did not result in an increase in the abundance and richness of aphid predators. Moreover, ladybeetles, representing the majority of trapped predators, were more abundant in mixtures with very low or intermediary functional diversity at sowing, especially in 2014. We hypothesise that certain flower species, which were abundant in certain mixtures (and not in those exhibiting the highest functional diversity), attracted predators and were sufficiently represented to support them. Our results present novel information that could be used to the development of flower mixtures that provide effective ecosystem services, such as pest control. [less ▲]

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See detailPest regulation and support of natural enemies in agriculture: Experimental evidence of within field wildflower strips
Hatt, Séverin ULg; Chevalier Mendes Lopes, Thomas ULg; Boeraeve, Fanny ULg et al

in Ecological Engineering (2017), 98

tRestoring ecosystem services in agriculture is vital to reach a sustainable food production. More specif-ically, developing farming practices which enhance biological pest control is a main issue for ... [more ▼]

tRestoring ecosystem services in agriculture is vital to reach a sustainable food production. More specif-ically, developing farming practices which enhance biological pest control is a main issue for today’sagriculture. The aim of this study was to assess whether the two strategies of complicating the search ofhost plants by pests by increasing plant diversity, and of supporting their natural enemies by managinghabitats, could be combined simultaneously at the field scale to restore biological pest control and reducechemical insecticide use. In Gembloux (Belgium), wildflower strips (WFS) were sown within wheat cropsin which pests (i.e., aphids), their predators (i.e. aphidophagous hoverflies, lacewings and ladybeetles)and parasitoid wasps were monitored for 10 weeks in the period of May through July 2015 as indicatorsof the ES of pest control. Aphids were significantly reduced and adult hoverflies favoured in wheat inbetween WFS, compared to monoculture wheat plots. No significant differences were observed for adultlacewings, ladybeetles and parasitoids. In all treatments, very few lacewing and ladybeetle larvae wereobserved on wheat tillers. The abundance of hoverfly larvae was positively correlated with the aphid den-sity on tillers in between WFS, showing that increasing food provisions by multiplying habitats withinfields, and not only along margins, can help supporting aphidophagous hoverflies in crops. By enhancingthe ecosystem services of biological pest control, this study shows that increasing both plant diversityand managing habitats for natural enemies may reduce aphid populations, hence insecticide use. Futureresearch should continue this vein of work by quantifying the link between agricultural practices and thedelivery of ecosystem services in order to guide future measures of agricultural policies. [less ▲]

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See detail两种挥发性化学信息素与小麦-豌豆间作协同作用
Xu, Qingxuan ULg; Chevalier Mendes Lopes, Thomas ULg; Hatt, Séverin ULg et al

Conference (2016, November 10)

当今的害虫防治理念已从传统的“杀灭”转向科学的“调控”,生态调控成为可持续农业领域中的研究热点之一。间作提高农作物的多样性是作物虫害生态调控途径之一,间作作物导致农田生物多样性增加、为天敌昆虫提供食物和避难所,从而使天敌种类和数量增加,为目标害虫控治作用增强。已有结果表明小麦与豌豆间作、混作,不仅有效降低小麦上麦长管蚜的种群数量,增加了天敌控制害虫的稳定性和持续性, ... [more ▼]

当今的害虫防治理念已从传统的“杀灭”转向科学的“调控”,生态调控成为可持续农业领域中的研究热点之一。间作提高农作物的多样性是作物虫害生态调控途径之一,间作作物导致农田生物多样性增加、为天敌昆虫提供食物和避难所,从而使天敌种类和数量增加,为目标害虫控治作用增强。已有结果表明小麦与豌豆间作、混作,不仅有效降低小麦上麦长管蚜的种群数量,增加了天敌控制害虫的稳定性和持续性, 而且可以增产保收、养地改土。一些昆虫取食诱导的挥发物和昆虫自身分泌物(如水杨酸甲酯MeSA、蚜虫报警信息素EBF)具有驱避蚜虫对植食性昆虫进行行为调控的直接防御,还可以通过吸引第三级营养级的天敌昆虫,提升间接防御害虫作用。 为了探索作物间作与行为调控挥发物的协同的控害效果,本研究采用小麦间作豌豆、协同化学信息素(MeSA、EBF)的释放,于比利时Gembloux地区连续两年(2015年3月-8月年和2016年3月-8月)进行田间实验。结果表明与单纯小麦-豌豆间作相比,小麦-豌豆间作配合EBF、MeSA的释放,提高了蚜茧蜂对豌豆蚜的寄生率,对蚜虫天敌草蛉、食蚜蝇、瓢虫也具有强烈的吸引作用,豌豆蚜及麦蚜的无翅蚜田间发生量分别降低达35%和30%。 间作的豌豆可以为天敌提供栖居和食物,有利于蚜虫天敌的繁殖,而豌豆蚜的发生峰期早于麦蚜发生峰期一周左右,因此间作结合挥发物的释放,更有利于豌豆田中的蚜虫主要天敌最大程度的转移到麦田中防控麦蚜,有效降低麦蚜发生峰期的种群数量,两种方法组合构成“吸引-补偿”(Attract–Reward)的机制,将挥发物行为调控与栖境管理两种防控害虫的方法有效的结合起来,进一步增强生防效果,有助于建立综合的小麦害虫绿色防控体系。 [less ▲]

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See detailTransmission Efficiency of Cucumber Mosaic Virus by Myzus persicae According to Virus Strain and Aphid Clone from China
Bosquée, Emilie ULg; Yin, Ronling; Bragard, Claude et al

in Asian Journal of Plant Pathology (2016)

Background: Cucumber mosaic virus (CMV) is one of the most important viruses infecting vegetables in the fields throughout the world. Transmission efficiency of CMV could depend on the variability of ... [more ▼]

Background: Cucumber mosaic virus (CMV) is one of the most important viruses infecting vegetables in the fields throughout the world. Transmission efficiency of CMV could depend on the variability of virus strain but also aphid vector species and/or clones. Materials and Methods: By sequence analysis, the coat protein gene of CMV strains from different regions revealed that the CMV isolates used for this study belong to the same group. Both CMV strains and Myzus persicae (Sulzer) aphid clones were investigated for their role in viral dispersion by reciprocal tests on Nicotiana tabacum (L.) using the same clone of Myzus persicae towards different CMV strains or using one CMV strain on different Myzus persicae clones. Results: Virus transmission efficiency was found to be significantly influenced by selected CMV strains (from 5-30% of transmission rate for identical aphid clone) and also by the selected aphid clones (variation from 15-70% of transmission rate for identical virus strain). Conclusion: The CMV transmission efficiency depends on the variability of virus strain but also aphid vector clones. Combining the variability of CMV transmission rates for both aphid and virus sides, the prediction and modeling of virus spreading seems to be difficult to organize and are closely dependent on the variability of each protagonist-aphid and virus. [less ▲]

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See detailUse of slow-release plant infochemicals to control aphids: a first investigation in a Belgian wheat field
Zhou, Haibo; Chen, Longsheng; Liu, Yong et al

in Scientific Reports (2016)

Using infochemicals to develop a push–pull strategy in pest control is a potential way to promote sustainable crop production. Infochemicals from plant essential oils were mixed with paraffin oil for slow ... [more ▼]

Using infochemicals to develop a push–pull strategy in pest control is a potential way to promote sustainable crop production. Infochemicals from plant essential oils were mixed with paraffin oil for slow release in field experiments on wheat to control the population density of cereal aphids and to enhance their natural enemies. (Z)-3-Hexenol (Z3H) attracted Metopolophum dirhodum and Sitobion avenae, the predominant species on wheat in Belgium, and may be a useful infochemical for aphid control by attracting aphids away from field plots. Release of (E)-β-farnesene (EBF) or a garlic extract (GE) led to a significant decrease in the abundance of wheat aphids. The main natural enemies of cereal aphids found were lacewings (47.8%), hoverflies (39.4%), and ladybirds (12.8%). Ladybird abundance varied little before the end of the wheat-growing season. Our results suggest that these chemicals can form the basis of a “push–pull” strategy for aphid biological control, with GE and EBF acting as a pestand beneficial-pulling stimulus and Z3H for aphid pulling. [less ▲]

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See detailEffect of wheat-based intercropping systems on pests and natural enemies: a review with a special focus on China
Hatt, Séverin ULg; Chevalier Mendes Lopes, Thomas ULg; Xu, Qingxuan ULg et al

Conference (2016, April 16)

Intercropping is a farming practice consisting of cultivating at least two plant species simultaneously in the same field, but without necessarily sowing and/or harvesting them at the same time. By ... [more ▼]

Intercropping is a farming practice consisting of cultivating at least two plant species simultaneously in the same field, but without necessarily sowing and/or harvesting them at the same time. By increasing plant diversity at the field scale, intercropping may be an efficient method to control insect pests and support natural enemies on the associated crops. We performed a systematic research of the peer-reviewed literature which studied the effect of intercropping systems on pests and natural enemies, compared to pure stands. The research was restricted to wheat-based systems, as it is an important crop worldwide, and the main one in Northern China. A total of fifty research papers were obtained from the literature search. Results from a vote-counting analysis, using binomial tests, indicated that pest abundance was significantly reduced in intercropping systems compared with pure stands, but their natural enemies were not particularly favoured (i.e., predators and parasitoids). Among these papers, 23 were studies from China. There, wheat was associated with cotton in relay-intercropping, as well as alfalfa, chili peppers, fava bean, garlic, mung bean, oilseed rape and pea in strip-cropping. Aphids were systematically reduced and natural enemies (i.e., predators and parasitoids) significantly favoured in intercropping systems compared to pure stands. This study shows that intercropping is a viable practice to biologically control pests, and potentially support natural enemies, especially in China. Therefore it can be seen as a viable method to reduce insecticide use in wheat production systems. [less ▲]

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See detailWheat (Triticum aestivum L.)-based intercropping systems for biological pest control: a review
Chevalier Mendes Lopes, Thomas ULg; Hatt, Séverin ULg; Xu, Qingxuan ULg et al

in Pest Management Science (2016), 72

BACKGROUND: Wheat (Triticum aestivum L.) is one of the most cultivated crops in temperate climates. As its pests are mainly controlled with insecticides which are harmful to the environment and human ... [more ▼]

BACKGROUND: Wheat (Triticum aestivum L.) is one of the most cultivated crops in temperate climates. As its pests are mainly controlled with insecticides which are harmful to the environment and human health, alternative practices such as intercropping have been studied for their potential to promote biological control. Based on the published literature, this study aimed to review the effect of wheat-based intercropping systems on insect pests and their natural enemies. RESULTS: Fifty original research papers were obtained from a systematic search of the peer-reviewed literature. Results from a vote-counting analysis indicated that, in the majority of studies, pest abundance was significantly reduced in intercropping systems compared with pure stands. However, the occurrence of their natural enemies as well as predation and parasitism rates were not significantly increased. The country where the studies took place, the type of intercropping, and the crop that was studied in the association had significant effects on these results. CONCLUSION: These findings show that intercropping is a viable practice to decrease insecticide use in wheat production systems. Nevertheless, other practices could be combined with intercropping to favour natural enemies and enhance pest control. [less ▲]

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See detailEffects of Plant Defense Signal Molecules Jasmonic Acid and Salicylic Acid on the Expression of Detoxification Enzyme Glutathione S-transferases and Salivary Protein C002 in Myzus persicae
ZHANG, Yong; FAN, Jia; ZHAO, XingYan et al

in SCIENTIA SINICA Vitae (2016), 46(5), 665-672

Jasmonic acid (JA) and salicylic acid (SA) are important phytohormones for activating plant defense responses when plants suffer from mechanical damage or pest infestation. In response to plant defense ... [more ▼]

Jasmonic acid (JA) and salicylic acid (SA) are important phytohormones for activating plant defense responses when plants suffer from mechanical damage or pest infestation. In response to plant defense responses, insects usually increase the detoxification enzyme activity or secrete some saliva proteins into plants to modulate host cell processes to promote their adaptation. In this study, we used real-time qPCR to detect the relative gene expression of detoxification enzyme named glutathione S-transferases (sigma GST) and salivary gland-specific protein C002 in Myzus persicae after feeding with 5mM JA or 10mM SA through artificial diet. The results showed that the relative expression of sigma GST and C002 in M. persicae increased significantly after JA and SA treatments. The results revealed that M. persicae can use JA and SA as cues to up-regulate gene expression of related detoxification enzyme and saliva protein. Our results provided new insights into the research on the mechanism of M. persicae adaptation to host plant resistance. [less ▲]

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See detailOrco mediates olfactory behaviors and winged morph differentiation induced by alarm pheromone in the grain aphid, Sitobion avenae
Fan, Jia; Zhang, Yong; Francis, Frédéric ULg et al

in Insect Biochemistry and Molecular Biology (2015), 64

Olfaction is crucial for short distance host location and pheromone detection by insects. Complexes of olfactory receptors (ORs) are composed of odor-specific ORs and OR co-receptors (Orco). Orcos are ... [more ▼]

Olfaction is crucial for short distance host location and pheromone detection by insects. Complexes of olfactory receptors (ORs) are composed of odor-specific ORs and OR co-receptors (Orco). Orcos are widely co-expressed with odor-specific ORs and are conserved across insect taxa. A number of Orco orthologs have been studied to date, although none has been identified in cereal aphids. In this study, an Orco gene ortholog was cloned from the grain aphid, Sitobion avenae, and named “SaveOrco”; RNA interference (RNAi) reduced the expression of SaveOrco to 34.11% in aphids, resulting in weaker EAG (electroantennogram) responses to plant volatiles (Z-3-hexene-1-ol; methyl salicylate, MeSA) and aphid alarm pheromone (E-b-farnesene, EBF). Aphid wing differentiation induced by EBF was investigated in both RNAi treated and untreated aphids. EBF induced production of winged aphids in both pre-natal and postnatal periods in untreated aphids, but no such induction was observed in the RNAi-treated aphids. We conclude that SaveOrco is crucial for the aphid's response to pheromones and other volatiles, and is involved in wing differentiation triggered by EBF [less ▲]

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See detailEffets de deux associations culturales à base de blé sur les populations de pucerons (Homoptera: Aphididae) et d’auxiliaires aphidiphages: étude préliminaire menée en Chine
Chevalier Mendes Lopes, Thomas ULg; Bosquée, Emilie ULg; Honba, David et al

in Entomologie Faunistique = Faunistic Entomology (2014), 67

Crop associations have several advantages when plant species and crop production methods, including harvesting, are well selected. This preliminary study was conducted in the Shandong province (China) to ... [more ▼]

Crop associations have several advantages when plant species and crop production methods, including harvesting, are well selected. This preliminary study was conducted in the Shandong province (China) to better characterize the effect of wheat (Triticum aestivum L.)/oilseed rape (Brassica napus L.) and wheat/pea (Pisum sativum L.) associations on the aphid and aphidophagous beneficial populations. Aphids observed on wheat tillers were significantly more abundant in the pure stand of wheat during the two weeks prior to their population peak, compared with crop associations. Considering the aphidophagous beneficials, significantly more ladybirds were observed in the associations, compared with the pure stand during their abundance peak. Yellow pan traps were also used to assess the diversity and abundance of adult beneficial species. The parasitoid species Aphidius gifuensis (Ashmead) was prevalent. Among predators, Propylea japonica (Thunberg) and Harmonia axyridis (Pallas) were the most abundant species. This study contributes to better understand the potential of crop associations with wheat as a sustainable method to control aphid populations in this region of China. [less ▲]

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See detailEffects of wheat/oilseed rape and wheat/pea associations on the diversity of aphids and aphidophagous beneficials
Chevalier Mendes Lopes, Thomas ULg; Bosquée, Emilie ULg; Honba, David et al

Poster (2014, May 20)

This study was conducted in the Shandong province (China) to better characterize the effect of wheat/oilseed rape and wheat/pea associations on the populations of aphids and aphidophagous beneficials. At ... [more ▼]

This study was conducted in the Shandong province (China) to better characterize the effect of wheat/oilseed rape and wheat/pea associations on the populations of aphids and aphidophagous beneficials. At specific times of the season, the observations on wheat tillers confirm the resource concentration and the enemy hypotheses. In fact, aphids were more abundant in the pure stand of wheat, while more ladybirds were observed in the associations. As for the trapping of aphidophagous beneficials, the parasitoid species Aphidius gifuensis (Ashmead) was prevalent. Among predators, Propylea japonica (Thunberg) and Harmonia axyridis (Pallas) were the most abundant species. Few lacewings and hoverflies were trapped. This study shows a beneficial effect of crop associations on the control of aphid populations. [less ▲]

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See detailEvaluation of the aphid and aphidophagous beneficials diversity in a pea and potato association
Bosquée, Emilie ULg; Chevalier Mendes Lopes, Thomas ULg; Serteyn, Laurent ULg et al

Poster (2014, May 20)

Crop associations can have beneficial effects on the control of insect pests. This study was conducted in the Shandong province (China) to assess the impact of potatoes and peas association on the ... [more ▼]

Crop associations can have beneficial effects on the control of insect pests. This study was conducted in the Shandong province (China) to assess the impact of potatoes and peas association on the populations of aphids and aphidophagous beneficials. Observations on potato plants and trapping were performed. During the season, the degree of infestation didn’t differ significantly between the association and the pure stand. However, the aphidophagous beneficials were more abundant in the association comparing to the pure stand. Trapping results give a more general idea about the richness and diversity of natural enemies present in the environment. Aphidius gifuensis (Ashmead) and Aphelinus abdominalis Dalman are the most abundant parasitoids. Among predators, Propylea japonica (Thunberg) and Harmonia axyridis (Pallas) are prevalent. Few hoverflies and lacewings were trapped. Results from the observations on plants do not support the resource concentration hypothesis. However, the enemy hypothesis was confirmed for the aphidophagous beneficials. Therefore, this association can have a beneficial effect on the control of aphid populations. [less ▲]

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See detailBiological control of aphids in wheat and vegetable crops : a multi-approach case study in Shandong province (China)
Chevalier Mendes Lopes, Thomas ULg; Bosquée, Emilie ULg; Chen, Julian et al

Poster (2014, April 02)

This multi-approach study was conducted in the Shandong province (China) to assess the effectiveness of different biological control methods against aphids in wheat and vegetable crops. Three approaches ... [more ▼]

This multi-approach study was conducted in the Shandong province (China) to assess the effectiveness of different biological control methods against aphids in wheat and vegetable crops. Three approaches were tested: (1) wheat/oilseed rape and wheat/pea associations, (2) potatoes/peas association, and (3) E-β-farnesene (aphid alarm pheromone) releasers in squashes under plastic tunnels. Aphids and aphidophagous beneficials were monitored by observations on plants. Wheat associations and E-β-farnesene reduced aphid infestations compared with control treatments, while no effect was observed in the potatoes/peas association. Moreover, aphidophagous beneficials were significantly more abundant in the three kinds of associations compared with control treatments. Few individuals were observed on squashes. Additionally, adult aphidophagous beneficials were monitored using yellow pan traps. The parasitoid species Aphidius gifuensis (Ashmead) was prevalent, while Propylea japonica (Thunberg) and Harmonia axyridis (Pallas) were the most abundant species among predators. Globally, wheat associations were more efficient to reduce aphid infestations and attract aphidophagous beneficials to promote biological control. The trapping of natural enemies allowed to assess the diversity and abundance of aphidophagous species in this region. This study shows a beneficial effect of crop associations and E-β-farnesene on the control of aphid populations and contributes to assess the potentialities of these alternative methods to the use of insecticides. [less ▲]

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See detailInfluence of Garlic Intercropping or Active Emitted Volatiles in Releasers on Aphid and Related Beneficial in Wheat Fields in China
Haibo, Zhou; Chen, Julian; Yong, Liu et al

in Journal of Integrative Agriculture (2013), 12(3)

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See detailInvestigation of mevalonate pathway in aphids
Vandermoten, Sophie ULg; Yu, Wenjuan; Chen, Julian et al

Poster (2011, October)

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See detailGenetic variation among the geographic population of the grain aphid, Sitobion avenae (Hemiptera: Aphididae) in China inferred from mitochondrial COI gene sequence
Xu, Zhao-Huan; Chen, Julian; Cheng, Deng-Fa et al

in Agricultural Sciences in China (2011), 10(7), 1041-1048

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See detailDiscovery of English Grain Aphid (Hemiptera: Aphididae) Biotypes in China
Xu, Zhao-Huan; Chen, Julian; Cheng, Deng-Fa et al

in Journal of Economic Entomology (2011), 104(3), 1080-1086

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See detailDo aphids and their predators use the same OBP to transport a same odour?
Vandermoten, Sophie ULg; Fan, Jia; Liu, Yong et al

Poster (2010, August)

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