"Keitt' is moderately disease resistant, which hasn't been enough in the western, high-humidity communities, where the fruits are often quite gross. But it definitely is better at disease resistance than 'Kent'.
I hear, from Dr. Jonathon Crane, that there seems to be a worse strain of Anthracnose going around, that explains some of the severely damaged trees we have seen.
And then, there are the unconfirmed suspicions of a new-to-here bacterial disease on mangos.
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