Slide 1

Strategies for “managing” host resistance

Pathogen evolution: Resistance gene pyramiding and its effects on pathogens and pests

Example 1: Hessian fly on wheat

A gall midge – physical attack with mandibles followed by chemical attack with effectors

Resistant plants

Host resistance to Hessian fly

Slide 9

Sixteen Hessian fly biotypes, classified as 'GP' (Great Plains) and 'A' through 'O', have been identified on the basis of their differential response to H3, H5, H6, and H7H8.

Slide 11

How about gene pyramids?

Slide 13

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Slide 15

How does adding susceptible plants affect durability of resistance?

Slide 17