LUO , Chen

Symbiosis is omnipresent in nature. In these intimate and prolonged associations between different organisms, the effect of gene expression from one partner on the other can lead to the appearance of new phenotypes, a concept called "extended phenotype". My thesis focuses on the study of host-parasitoid-symbiont interactions in aphids, mainly...

Many insects harbor heritable endosymbionts, whether obligatory or facultative, and the role of facultative endosymbionts in shaping the phenotype of these species has become increasingly important. However, little is known about whether micro-injected endosymbionts can have any effects on aphid clones, which was measured using various...

Stable infections of maternally transmitted secondary endosymbionts in aphids are frequently found in field populations; however, whether this phenomenon changes in artificial lab conditions has not been clear. To investigate, (1): we collected Sitobion avenae (Fabricius) from six different regions and detected the three common secondary...

In recent decades, man-made electric fields have greatly increased the intensity of electrostatic fields that are pervasively present in the environment. To better understand the physiological alterations exhibited by herbivorous insects in response to changing electric environments, we determined the activities of anti-oxidative enzymes and...

Hormone-dependent responses in host plants induced by herbivore infestation have species-specific effects. This study focused on determining the relative expression profiles of the genes associated with hormone-dependent pathways in two near-isogenic wheat lines when attacked by cereal aphids. Infestation with Rhopalosiphum padi Linnaeus...

Over the past 14 years, the chemical hybridization agent SQ-1 (CHA-SQ-1) has been widely used for inducing male sterility in wheat heterosis in China. However, any indirect effects of CHA-SQ-1 on high trophic level of food chains (e.g., wheat pests) have not been tested. Therefore, we addressed the question, under laboratory conditions, by...

The English grain aphid, Sitobion avenae Fabricius (Hemiptera: Aphididae), and bird cherry-oat aphid, Rhopalosiphum padi L. (Hemiptera: Aphididae), are two common herbivore pests that have devastating effects on wheat production worldwide. To tolerate herbivores, plants coevolved various biological and morphological features. The present study...

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Previous studies have shown that Regiella insecticola modulated the parasitism rate in wheat aphid, Sitobion miscanthi. However, little is known about influences of the symbiont on wheat aphids by predators, the other important strategy used in biological control. Herein, we in the study examined effects of the R. insecticola on aphid...

Abstract The importance of secondary endosymbionts on the resistance to parasitoids is increasingly recognized. Compared with Hamiltonella defensa, our understanding of the role of Regiella insecticola in protecting hosts against parasitic wasps is not well documented. In this study, we conducted experiments to determine whether R. insecticola...

The Bemisia tabaci (Gennadius) cryptic species complex comprises important insect pests that cause devastating damage to agricultural crops worldwide. In China, the B. tabaci MED species, formerly known as biotype 'Q', has surpassed the MEAM1 species, formerly known as biotype 'B', which is threatening agricultural production all over the...

Previous data showed that the parasitoid wasp Aphelinus asychis was more successful on Sitobion avenae clones artificially infected with different strains of Regiella insecticola compared to the same clones lacking facultative symbionts. To test whether this resulted from a specific interaction between the aphid and symbiont genotype, we used...

In agmecosystems, plant-pest interactions are at the basis of complex food webs, which can be affected by both biotic and abiotic factors. In the present study, we evaluated the impact of the insecticide beta-cypermethrin on interspecific interactions between the specialist aphid Aphis glycines and the generalist aphid Aulacorthum solani on...

Abstract Background Aphids often harbor bacterial symbionts that confer resistance to biotic and abiotic stress. Previous studies have primarily examined the direct effects of symbiont infection on parasitoid success but less on aphid population dynamics under indirect parasitic situations, for example when exposed to parasitoid wasp odor....

The pea aphid Acyrthosiphon pisum hosts different facultative symbionts (FS) which provide it with various benefits, such as tolerance to heat or protection against natural enemies (e.g. fungi, parasitoid wasps). Here, we investigated whether and how the presence of certain FS could affect phenoloxidase activity, a key component of insect...

BACKGROUND The complex interaction between plant viruses and their insect vectors is the basis for the epidemiology of plant viruses. The 'Vector Manipulation Hypothesis' (VMH) was proposed to demonstrate the evolution of strategies in plant viruses to enhance their transmission to new hosts through direct effects on insect vector behavior...

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