1968, M. J. Crampton and L. E. Watts, "Genetic Studies of Pea Leaf-Roll (Top-Yellows) Virus Resistance in Pisum sativum," New Zealand Journal of Agricultural Research, vol, 11, no. 4, p. 773 (Google preview):Circumstantial evidence suggests that heavy infestation by viruliferous aphids can overcome the highest degree of host plant resistance.
1992 Sept. 3, "Farmers concerned about frost, wheat ready for planting," McCook Daily Gazette, p. 8 (retrieved 6 March 2013)Viruliferous curl mites increase during summer on volunteer wheat, and are carried by air currents into the new wheat crop.
2007 July 10, "Resistant variety of maize giving some hope," The Hindu (retrieved 6 March 2013)Maize streak virus, an endemic pathogen of native African grasses, was then carried to maize plants by viruliferous leafhoppers.
