The allelic frequency at equilibrium (qˆ) depends on the relative fitnesses (usually expressed as selection coefficients) of the two homozygotes:

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#Unit 6. System Physiology – Plant

Maize genotypes that carry the Hm1 gene, which encodes an enzyme that can metabolize and thereby detoxify HC toxin are resistant to C. carbonum.

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#Unit 6. System Physiology – Plant

Alternaria alternata f. sp. lycopersici produces the AAL toxin,

which activates a plant cell death program in tomato (Solanum

lycopersicum) leaves.

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#Unit 6. System Physiology – Plant

ToxA is produced by both Stagonospora nodorum and Pyrenophora tritici‐repentis, which cause glume blotch and tan spot disease, respectively, on wheat (Triticum spp.).

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#Unit 6. System Physiology – Plant

The ToxA gene encodes a 13‐ kDa polypeptide. ToxA stimulates host cell death in a light dependent manner by binding to Plastocynin.

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#Unit 6. System Physiology – Plant

Xanthomonas, produces TAL (transcription activator‐like) effectors contribute to disease formation or trigger defense by binding host DNA and activating effector‐specific host genes.

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#Unit 6. System Physiology – Plant

PthXo1, a TAL effector of the rice pathogen Xanthomonas oryzae, activates expression of the rice gene Os8N3, allowing Xanthomonas to colonize rice plants.