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PremisePolyploidy is known to cause physiological changes in plants which, in turn, can affect species interactions. One major physiological change predicted in polyploid plants is a heightened demand for growth‐limiting nutrients. Consequently, we expect polyploidy to cause an increased reliance on the belowground mutualists that supply these growth‐limiting nutrients. An important first step in investigating how polyploidy affects nutritional mutualisms in plants, then, is to characterize differences in the rate at which diploids and polyploids interact with belowground mutualists. MethodsWe usedHeuchera cylindrica(Saxifragaceae) to test how polyploidy influences interactions with arbuscular mycorrhizal fungi (AMF). Here we first confirmed the presence ofAMFinH. cylindrica, and then we used field‐collected specimens to quantify and compare the presence ofAMFstructures while controlling for site‐specific variation. ResultsTetraploids had higher colonization rates as measured by total, hyphal, and nutritional‐exchange structures; however, we found that diploids and tetraploids did not differ in vesicle colonization rates. ConclusionsThe results suggest that polyploidy may alter belowground nutritional mutualisms with plants. Because colonization by nutritional‐exchange structures was higher in polyploids but vesicle colonization was not, polyploids might form stronger associations with theirAMFpartners. Controlled experiments are necessary to test whether this pattern is driven by the direct effect of polyploidy onAMFcolonization.
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This content will become publicly available on May 1, 2026
Possible Limitations in the Management of a Small Ant Pest Species ( Plagiolepis alluaudi ) Using Gel Baits
ABSTRACT Alluaud's little yellow ant,Plagiolepis alluaudiEmery 1894, (Hymenoptera: Formicidae), is an emerging nuisance species in floriculture and residential areas around the globe. Originally described from Madagascar, it ranks among the smallest widespread formicine pests. To date, no evaluations of management protocols for this species have been reported. In ants, feeding preference is related to ant body size and viscosity and nutritional content of the food source. Optimizing these factors could lead to improved bait performance. To assess population management implications of various bait parameters on a small pest ant species, four commercial ant baits of varying viscosities, active ingredient (AI) group and concentration, and nutritional content were evaluated in laboratory and field assays againstP. alluaudi. All four products negatively affectedP. alluaudisurvival compared to the untreated control, and all products were associated with greater visitation compared to the control, suggesting all AIs tested are viable candidates forP. alluaudimanagement. However, their direct use for population management in the field may be limited, as feeding cessation was eventually observed on all four baits. When baits were diluted with water, viscosity was reduced and survival was initially higher compared to with undiluted baits. However, similarly low levels of survival were maintained over time. Most importantly, we found in a 2‐year observational field study involving sustained baiting within an infested structure that only the bait formulation with the lowest overall viscosity was able to alleviateP. alluaudinuisance indoors. Our results suggest that diluting baits may be a viable strategy for targeting very small pest ant species, and the greater time to lethality of diluted baits, resulting from reduced toxicant concentration, may be a reasonable trade‐off allowing smaller ant species to continue feeding for a sufficient duration on a bait formulation.
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- Award ID(s):
- 2026772
- PAR ID:
- 10643666
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Applied Entomology
- Volume:
- 149
- Issue:
- 4
- ISSN:
- 0931-2048
- Page Range / eLocation ID:
- 626 to 636
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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