Southern Red Mite in Abelia

Approximately 400 different genotypes of Abelia (Caprifoliaceae) (species, interspecific hybrids, backcross hybrids and commercial cultivars) were screened for Southern Red mite (Oligonychus ilicis (McGregor)) damage in field plots on the University of Georgia Griffin Campus, Griffin, GA during the spring of the years 2011 and 2013. A visual rating scale of 0 to 3 was used to assess the damage, with 0 indicating no damage and 3 indicating severe damage. Southern red mite damage occurred in the spring on new growth. Severely affected plants were partially defoliated and new foliage was deformed. Leaf stippling was evident on all affected plants. Plants recovered by mid-summer and no damage was seen in the fall. Genotype had a highly significant effect on the level of spider mite damage (p <0.0001), with the backcross hybrids showing the most damage followed by the commercial hybrids. The interspecific hybrids and the species had little or no damage. A multiple means comparison test using Tukey revealed that the backcross hybrids were significantly more damaged than were the species (p < 0.05), interspecific hybrids (p < 0.0001), and commercial cultivars (p < 0.0001). The effect of pruning was significant (p =< 0.05); the pruned genotypes were less susceptible to spider mite damage. No interaction between genotype and pruning was found (p = 0.2328).