Mi-1.2, an R gene for aphid resistance in tomato, has direct negative effects on a zoophytophagous biocontrol agent, Orius insidiosus.
MetadataShow full item record
Mi-1.2 is a single dominant gene in tomato that confers race-specific resistance against certain phloem-feeding herbivores including aphids, whiteflies, psyllids, and root-knot nematodes. Few prior studies have considered the potential non-target effects of race-specific resistance genes (R genes), and this paper evaluates the compatibility of Mi-mediated resistance in tomato with a beneficial zoophytophagous predator, Orius insidiosus (Say). In addition to preying on aphids and other pests, this piercing-sucking insect also feeds from the xylem, epidermis, and/or mesophyll, and oviposits within plant tissues. Comparison of O. insidiosus confined to isogenic tomato plants with and without Mi-1.2 revealed that immatures of O. insidiosus had lower survival on resistant plants even when the immatures were provisioned with prey that did not feed on the host plant. Molecular gut content analysis confirmed that adults and immatures of O. insidiosus feed on both resistant (Mi-1.2+) and susceptible (Mi-1.2-) genotypes, and bioassays suggest that resistance does not affect oviposition rates, plant sampling, or prey acceptance by O. insidiosus adults. These results demonstrate a direct negative impact of R-gene-mediated host plant resistance on a non-target beneficial species, and reveal that Mi-mediated resistance can impact organisms that do not feed on phloem sap. Through laser capture microdissection and RT-PCR, Mi-1.2 transcripts were detected in the epidermis and mesophyll as well as the phloem of tomato plants, consistent with our observations that Mi-mediated resistance is active outside the phloem. These results suggest that the mode of action and potential ecological impacts of Mi-mediated resistance are broader than previously assumed.
- All Faculty Deposits 
Showing items related by title, author, creator and subject.
Individual Experiments to Evaluate the Effects of Plant Population and Planting Date, Cultivar and Plant Growth Regulator Application, and Herbicide and Plant Growth Regulator Application on Cotton (Gossypium hirsutum L.) Growth and Development, Yield, and Fiber Quality O'Berry, Nathan Brook (Virginia Tech, 2007-06-21)Cotton (Gossypium hirsutum L.) growth and development, lint yield, and fiber quality are influenced by many management decisions. Three field experiments examining the interaction of plant population and planting date, ...
Protecting plants and plant habitat from invasive alien species: A look at the global strategy for plant conservation The Global Invasive Species Programme (GISP) (2002)In 2002, the Parties to the Convention on Biological Diversity (CBD) adopted a Global Strategy for Plant Conservation (GSPC). GSPC Target 10 is that Management plans in place for at least 100 major alien species that ...
Natural Plant Hormones Are Biostimulants Helping Plants Develop Higher Plant Antioxidant Activity For Multiple Benefits O'Dell, Charles R. (Virginia Cooperative Extension, 2009)Discusses the use of plant growth hormones to improve growth and production of crop plants.