Dear Majid,

The following is an abstract of an article which answers your question in detail. Please check it and another related publication at the following links.

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SM Najim

Abstract

It is a commonly held view that genetically homogenous host populations are more vulnerable to infection than genetically diverse populations. The underlying idea, known as the 'monoculture effect,' is well documented in agricultural studies. Low genetic diversity in the wild can result from bottlenecks (that is, founder effects), biparental inbreeding or self-fertilization, any of which might increase the risk of epidemics. Host genetic diversity could buffer populations against epidemics in nature, but it is not clear how much diversity is required to prevent disease spread. Recent theoretical and empirical studies, particularly in Daphnia populations, have helped to establish that genetic diversity can reduce parasite transmission. Here, we review the present theoretical work and empirical evidence, and we suggest a new focus on finding 'diversity thresholds.'

https://www.researchgate.net/publication/227397921_Does_genetic_diversity_limit_disease_spread_in_natural_host_populations

http://www.journals.uchicago.edu/doi/pdf/10.1086/652430

Article Does genetic diversity limit disease spread in natural host ...

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Majid bannai