Genetics of Resistance to <em>Phytophthora capsici</em> in the Pepper Line 'SCM-334'

In order to establish a genetic model of the resistance to Phytophthora capsici in Capsicum annuum genotype &#39;SCM-334&#39;, two experiments were conducted which included &#39;SCM-334&#39;, as well as, the susceptible line &#39;Morr&#243;n INIA 224&#39; and their F1, F2, F3 and BC1 generations. We also tried to introgress a recessive gene, hypothetically responsible for resistance to P. capsici, from &#39;SCM-334&#39; into &#39;Morr&#243;n INIA 224&#39;. Inoculations were made, when plants had 4--6 leaves, by irrigating the culture substrate with a zoospore suspension of P. capsici isolate &#39;BI&#39;. The χ&#178; test was applied to segregating generations to determine how many genes were involved in resistance. The hypothesis which explained the obtained segregations best, although not completely, was one that assumes 3 genes in &#39;SCM-334&#39;, with at least 3 alleles in the heterozygous condition or 4 at any position, present in any genotype in order to be resistant. The influence of the isolate&#39;s aggressiveness and the inoculation method on the results are discussed. [ABSTRACT FROM AUTHOR]