Developmental and reproductive performance of a specialist herbivore depend on seasonality of, and light conditions experienced by, the host plant

AbstractThe ongoing global temperature rise has led to increasing frequency of drought events, negatively impacting vegetation and the living organisms relying on it. Extreme drought killing host plants can clearly reduce herbivore fitness, but the impact of moderate host plant water stress on insect herbivores can vary, and may even be beneficial. The Finnish Glanville fritillary butterfly (Melitaea cinxia) has faced reduced precipitation in recent years, which has impacted population dynamics. However, whether the negative effects depend on extreme desiccation killing the host plant or moderate drought impacting plant quality remains unclear. We assessed the performance of larvae fed on moderately water-stressed Plantago lanceolata in terms of growth, gut microbial composition and immune response. We found that larvae fed on water-stressed plants had better growth, a more heterogeneous bacterial community and a shifted fungal community in the gut, and up-regulated the expression of one candidate immune gene (pelle), whereas survival remained unaffected. Most of the measured traits showed considerable variation due to family structure. Our data suggest that in temperate regions moderate host plant water stress can positively shape resource acquisition of this specialized insect herbivore, potentially by increasing nutrient accessibility or concentration. Potentially, the better larval performance may be mediated by a shift of the microbiota on water-stressed plants, calling for further research especially on the understudied gut fungal community.

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A specialist herbivore suppresses host plant resistance by inducing a leucine-rich repeat receptor-like kinase

Authorea ◽

10.22541/au.158637615.56825101 ◽

2020 ◽

Author(s):

Meng Ye ◽

Peng Kuai ◽

Lingfei Hu ◽

Miaofeng Ye ◽

Hao Sun ◽

...

Keyword(s):

Host Plant ◽

Plant Resistance ◽

Host Plant Resistance ◽

Leucine Rich Repeat ◽

Specialist Herbivore ◽

Receptor Like Kinase

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Climate Change and Local Host Availability Drive the Northern Range Boundary in the Rapid Expansion of a Specialist Insect Herbivore, Papilio cresphontes

Frontiers in Ecology and Evolution ◽

10.3389/fevo.2021.579230 ◽

2021 ◽

Vol 9 ◽

Author(s):

J. Keaton Wilson ◽

Nicolas Casajus ◽

Rebecca A. Hutchinson ◽

Kent P. McFarland ◽

Jeremy T. Kerr ◽

...

Keyword(s):

Data Collection ◽

Host Plant ◽

Rapid Change ◽

Rapid Expansion ◽

Insect Herbivore ◽

Specialist Herbivore ◽

Recent Emergence ◽

Specialist Insect ◽

Community Science ◽

Analytical Approaches

Species distributions, abundance, and interactions have always been influenced by human activity and are currently experiencing rapid change. Biodiversity benchmark surveys traditionally require intense human labor inputs to find, identify, and record organisms limiting the rate and impact of scientific enquiry and discovery. Recent emergence and advancement of monitoring technologies have improved biodiversity data collection to a scale and scope previously unimaginable. Community science web platforms, smartphone applications, and technology assisted identification have expedited the speed and enhanced the volume of observational data all while providing open access to these data worldwide. How to integrate and leverage the data into valuable information on how species are changing in space and time requires new best practices in computational and analytical approaches. Here we integrate data from three community science repositories to explore how a specialist herbivore distribution changes in relation to host plant distributions and other environmental factors. We generate a series of temporally explicit species distribution models to generate range predictions for a specialist insect herbivore (Papilio cresphontes) and three predominant host-plant species. We find that this insect species has experienced rapid northern range expansion, likely due to a combination of the range of its larval host plants and climate changes in winter. This case study shows rapid data collection through large scale community science endeavors can be leveraged through thoughtful data integration and transparent analytic pipelines to inform how environmental change impacts where species are and their interactions for a more cost effective method of biodiversity benchmarking.

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Aphid Species Specializing on Milkweed Have Distinct Bacterial Symbiont Communities

10.21203/rs.3.rs-399030/v1 ◽

2021 ◽

Author(s):

Laramy Enders ◽

Thorsten Hansen ◽

Kirsten Brichler ◽

John Couture ◽

Elizabeth French

Keyword(s):

Host Plant ◽

Bacterial Species ◽

Aphid Species ◽

Community Diversity ◽

Plant Interactions ◽

Specialist Herbivore ◽

Host Plant Specialization ◽

Chemical Profiles ◽

Induced Changes ◽

Defensive Chemical

Abstract Host plant range is arguably one of the most important factors shaping microbial communities associated with insect herbivores. However, it is unclear whether host plant specialization limits microbial community diversity or to what extent herbivores sharing a common host plant evolve distinct microbiomes. To investigate whether variation in host plant specialization influences the composition of herbivore symbiont populations we compared bacterial diversity across three milkweed aphid species (Aphis nerii, Aphis asclepiadis, Myzocallis asclepiadis) feeding on a common host plant (Asclepias syriaca) using 16S rRNA metabarcoding. Overall, bacterial species richness did not vary with degree of host plant specialization. However, aphid species harbored distinct bacterial communities that varied in composition and relative abundance of key symbionts. Differences in aphid microbiomes were primarily due to strain variation in the obligate symbiont Buchnera and facultative symbiont Arsenophonus, as most of the low-abundant taxa were found in all three species. Interestingly, A. asclepiadis harbored a greater diversity of unique strains of Buchnera and significantly higher Arsenophonus relative abundances compared to the other two aphid species. Although many low abundance microbes were shared across all milkweed aphids, key differences exist in symbiotic partnerships that could influence additional ecological variation, including variation in ant tending observed across milkweed aphid species via microbial induced changes to honeydew or defensive chemical profiles. This study suggests generalist and specialist herbivore microbiomes are similar when feeding on a common host plant and highlights an intriguing potential role for strain level variation of key aphid symbionts in host-plant interactions.

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