|Ohm, Herb - PURDUE UNIVERSITY|
|Patterson, F - PURDUE UNIVERSITY|
Submitted to: Plant Breeding Reviews
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 20, 2001
Publication Date: N/A
Interpretive Summary: The main purpose of this review is to bring together current information on the use of resistant wheat varieties to control Hessian fly injury in wheat. During the last 50 to 60 years, resistant wheat varieties have provided the most reliable and economical control of the Hessian fly. Numerous sources of resistance have been identified from common and durum wheat, wild wheat relatives, and rye. These sources have been utilized in university and commercial wheat breeding programs to incorporate resistance into both spring and winter wheat varieties. This review presents a brief description of Hessian fly distribution, biology, life history and nature of damage to wheat, but the main purpose is to bring together information on the use of plant resistance in breeding resistant wheat varieties, and how the genetic interactions of the Hessian fly and wheat affects the durability of resistance. The discussion of resistance covers sources of resistance genes, mechanisms or modes of action in the plant that influenc the expression of resistance, genetics of resistance, the impact of evolution of resistance-breaking Hessian fly races (biotypes) on the long-term effectiveness of resistance genes in the plant, and selection protocols and breeding strategies for Hessian fly resistance that are considered important for maintaining plant resistance as a key management tool.
Technical Abstract: The Hessian fly, Mayetiola destructor (Say) is a destructive pest of wheat throughout most of the world. Control methods for the fly are mostly preventive and include the planting of resistant wheat cultivars, delayed seeding of winter wheat to escape fall infestation, and destroying volunteer wheat. Numerous sources of Hessian fly resistance have been identified in wheat and wheat relatives, and a relatively small portion of these have been utilized in the development of resistant cultivars. Resistance in these sources is dominant, partially dominant, or recessive, and conditioned by single, duplicate, or multiple genetic factors. The evolution of virulent biotypes of the insect in response to deployment of resistant wheat cultivars is a major concern in maintaining durability of resistance. The main strategies for breeding wheat for Hessian fly resistance include (a) using single gene resistances and deploying new single genes when necessary that are effective against resistance-breaking biotypes, (b) deploying effective gene resistances two or more at a time, (c) same as (b) but including a portion of susceptible plants to slow virulence change in the Hessian fly populations, and (d) providing the same resistance source in both parents so that commercial hybrid wheat is homozygous for resistance since partial dominance occurs in the heterozygote. Both classical plant breeding and DNA marker-assisted methods are being investigated for incorporating multiple genes in wheat cultivars. In choosing a breeding strategy it is important to determine the potential adaptation of Hessian fly to an area and risk of damage by the insect, and the time required to produce a resistant wheat cultivar relative to the severity of the Hessian fly problem.