Graciela Ávila-Quezada

An initial assessment of genetic diversity for Phytophthora capsici in northern and central Mexico

Phytophthora capsici causes significant damage to vegetable production in Mexico, but very little is known about the population structure or how populations survive and spread. The objective of the present study was to evaluate the genetic diversity of P. capsici isolates recovered from 1998–2014 in central and northern Mexico. Isolates (n = 81) were genotyped for 33 polymorphic single nucleotide polymorphism (SNP) loci using a targeted sequencing approach. There were a total of 72 unique genotypes and both the A1 and A2 mating types were common in both regions. Genetic analyses suggest clonal reproduction may play a more prominent role in the north, but the large proportion of unique genotypes and the finding of both mating types throughout both regions suggests outcrossing and sexual recombination likely play an important role in the overall epidemiology. Further studies with finer scale sampling at single locations over multiple years will be valuable.

Pomegranate fruit rot caused by Pilidiella granati in Mexico

During the spring of 2015, fruit rot symptoms were observed on pomegranate fruit in an orchard located in Oaxaca, Mexico. Characteristic lesions were collected and a fungus was isolated from these lesions. Based on morphological characteristics, analysis of rDNA-ITS sequences, and pathogenicity tests on pomegranate fruits, the causal agent was identified as Pilidiella granati. This is the first report of P. granati causing pomegranate fruit rot in Mexico.