Annual outbreaks of green peach aphid, Myzus persicae (Sulzer), limit commercial production of brassica crops, especially in organic systems in subtropical areas such as South Texas. We assessed the influence of companion plants that emit attractant, repellent, and natural enemy-attractant stimuli (i.e., insectary plants) on abundance of green peach aphid in organic kale (Brassica oleracaea L. var. acephala) fields in South Texas. We also monitored the assemblage of arthropod predators and parasitoids on kale and evaluated the response of numerically dominant species to companion plants. Indian mustard (Brassica juncea (L.) Vassiliĭ Matveievitch Czernajew; attractant), dill (Anethum graveolens L.; repellent), fennel (Foeniculum vulgare Mill.; repellent), and buckwheat (Fagopyrum esculentum Moench; insectary) were interplanted in 0.4-ha fields of organic kale varieties ‘Lacinato’ and ‘Vates’. Manual, sticky-trap, and pitfall sampling were used to repeatedly assess green peach aphids and arthropod natural enemies on kale immediately neighboring test companion plants. Numerically dominant (more than 60% of all individuals) natural enemies were Pterostichus sp. in pitfall samples, and larval and adult convergent lady beetle, Hippodamia convergens (Guérin-Méneville), in manual, sticky trap, and pitfall samples. The presence of nearby attractant, repellent, insectary plants did not significantly alter abundance of green peach aphid or numerically dominant natural enemy species on kale plants. Our findings might indicate limited potential of companion plants in regulating aphids in South Texas, but we make recommendations for future research that considers spatial relationships between crops and companion plants and effects on aphids and natural enemies.
Carlo R. Moreno and Alexis E. Racelis "Attraction, Repellence, and Predation: Role of Companion Plants in Regulating Myzus persicae (Sulzer) (Hemiptera: Aphidae) in Organic Kale Systems of South Texas," Southwestern Entomologist 40(1), 1-14, (1 March 2015). https://doi.org/10.3958/059.040.0101