Compatibility of biocontrol agents with host plant resistance for management of the South American tomato pinworm Phthorimaea absoluta

Integrating host plant resistance with biocontrol agents represents a promising strategy for sustainable management of Phthorimaea (Tuta) absoluta (Meyrick) (Lepidoptera: Gelechiidae), an invasive pest that poses a significant global threat to tomato production. However, morphological resistance traits, secondary metabolites, and plant volatiles in tomato may have adverse effects on natural enemies, thereby influencing the overall efficacy of pest control. This study evaluated the performance of three natural enemies across six tomato genotypes exhibiting various levels of resistance to P. absoluta. First, we evaluated the performance of the parasitoid Trichogramma achaeae on eggs, derived from moths reared on the different tomato genotypes, both in isolation and when presented on respective tomato leaflets. Second, we assessed the performance of the parasitoid Necremnus tutae on tomato genotypes that hosted P. absoluta larvae. And finally, we investigated the predatory capacity of the mirid Macrolophus pygmaeus on tomatoes hosting eggs and larvae of P. absoluta, all derived from moths reared on these genotypes, as well as the survival of predator nymphs on the different tomato genotypes, both with and without P. absoluta eggs. The P. absoluta-susceptible tomatoes, the resistant domesticated Corona F1 and the resistant wild tomato species Solanum neorickii had no significant impact on the parasitism and emergence rates of both parasitoids, or on the predatory efficacy and survival of predator nymphs. In contrast, the resistant wild Solanum arcanum negatively affected the performance of both parasitoids, reduced predatory efficacy and survival of first-instar nymphs, and increased the development time of predator nymphs. Our findings indicate that the resistant genotypes Corona F1 and S. neorickii appears to be compatible with all the natural enemies, whereas S. arcanum appears incompatible.