| Title: | Plant-mediated effects on an insect-pathogen interaction vary with intraspecific genetic variation in plant defences |
| Author(s): | Shikano I; Shumaker KL; Peiffer M; Felton GW; Hoover K; |
| Address: | "Department of Entomology and Center for Chemical Ecology, Pennsylvania State University, 501 ASI Building, University Park, PA, 16802, USA. ius15@psu.edu. Department of Biological and Environmental Sciences, University of West Alabama, Livingston, AL, 35470, USA. Department of Entomology and Center for Chemical Ecology, Pennsylvania State University, 501 ASI Building, University Park, PA, 16802, USA" |
| DOI: | 10.1007/s00442-017-3826-3 |
| ISSN/ISBN: | 1432-1939 (Electronic) 0029-8549 (Linking) |
| Abstract: | "Baculoviruses are food-borne microbial pathogens that are ingested by insects on contaminated foliage. Oxidation of plant-derived phenolics, activated by insect feeding, can directly interfere with infections in the gut. Since phenolic oxidation is an important component of plant resistance against insects, baculoviruses are suggested to be incompatible with plant defences. However, plants among and within species invest differently in a myriad of chemical and physical defences. Therefore, we hypothesized that among eight soybean genotypes, some genotypes would be able to maintain both high resistance against an insect pest and high efficacy of a baculovirus. Soybean constitutive (non-induced) and jasmonic acid (JA)-induced (anti-herbivore response) resistance was measured against the fall armyworm Spodoptera frugiperda (weight gain, leaf consumption and utilization). Indicators of phenolic oxidation were measured as foliar phenolic content and peroxidase activity. Levels of armyworm mortality inflicted by baculovirus (SfMNPV) did not vary among soybean genotypes when the virus was ingested with non-induced foliage. Ingestion of the virus on JA-induced foliage reduced armyworm mortality, relative to non-induced foliage, on some soybean genotypes. Baculovirus efficacy was lower when ingested with foliage that contained higher phenolic content and defensive properties that reduced armyworm weight gain and leaf utilization. However, soybean genotypes that defended the plant by reducing consumption rate and strongly deterred feeding upon JA-induction did not reduce baculovirus efficacy, indicating that these defences may be more compatible with baculoviruses to maximize plant protection. Differential compatibility of defence traits with the third trophic level highlights an important cost/trade-off associated with plant defence strategies" |
| Keywords: | Animals Genetic Variation *Herbivory Plant Leaves *Spodoptera Baculovirus Biological control Host plant quality Multitrophic interactions Tritrophic interactions; |
| Notes: | "MedlineShikano, Ikkei Shumaker, Ketia L Peiffer, Michelle Felton, Gary W Hoover, Kelli eng Research Support, U.S. Gov't, Non-P.H.S. Germany 2017/02/02 Oecologia. 2017 Apr; 183(4):1121-1134. doi: 10.1007/s00442-017-3826-3. Epub 2017 Jan 31" |
