Host plant resistance, foliar insecticide application and natural enemies play a role in the management of Melanaphis sorghi (Hemiptera: Aphididae) in grain sorghum

Authors: UYI, OSARIYEKEMWEN - University Of Georgia; LAHIRI, SRIYANKA - University Of Florida; Ni, Xinzhi; BUNTIN, DAVID - University Of Georgia; JACOBSON, ALANA - Auburn University; REAY-JONES, FRANCIS P.F. - Clemson University; PUNNURI, SOMASHEKHAR - Fort Valley State University; HUSETH, ANDERS - North Carolina State University; TOEWS, M - University Of Georgia

Submitted to: Frontiers in Plant Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/19/2022
Publication Date: 9/15/2022
Citation: Uyi, O., Lahiri, S., Ni, X., Buntin, D., Jacobson, A., Reay-Jones, F., Punnuri, S., Huseth, A.S., Toews, M.D. 2022. Host plant resistance, foliar insecticide application and natural enemies play a role in the management of Melanaphis sorghi (Hemiptera: Aphididae) in grain sorghum. Frontiers in Plant Science. 13:1006. https://doi.org/10.3389/fpls.2022.1006225.
DOI: https://doi.org/10.3389/fpls.2022.1006225

Interpretive Summary: The sugarcane aphid is a serious pest of sorghum production in the southern USA. Demonstration of integrated strategies and technologies that provide effective control is key to management of this invasive pest. The current study showed that foliar insecticide application significantly suppressed sugarcane aphid infestations on both the resistant and susceptible sorghum cultivars across all five locations across four southeastern U.S. states, that is, Alabama, Georgia, North and South Carolinas. Plant damage ratings did not vary widely, but the increase in aphid number resulted in corresponding increase in plant damage. Although there was not a strong influence of aphid resistance in sorghum variety on grain yield across the locations, but foliar insecticide application generally preserved grain yield. Both sorghum hybrids also supported an array of different life stages of predators and parasitoids with both the sprayed and non-sprayed treatments. Results suggest that the integration of natural enemies with insecticide is critical in the management of this invasive pest.

Technical Abstract: The invasive Melanaphis sorghi (Theobald) (=Melanaphis sacchari Zehntner) is a serious pest of sorghum production in the southern USA. Demonstration of technologies that provide effective control is key to management of this pest. Here, we investigated the effect of host plant resistance (resistant cultivar: DKS37-07 and susceptible cultivar: DKS53-53) and a single foliar insecticide (flupyradifurone: Sivanto Prime) application on M. sorghi infestations and the role of natural enemy populations in grain sorghum production across five locations in four states in southeastern USA. Foliar insecticide application significantly suppressed M. sorghi infestations on both the resistant and susceptible sorghum cultivars across all locations. Plant damage ratings did not vary widely, but there was generally a positive association between aphid counts and observed plant damage, suggesting that increasing aphid numbers resulted in corresponding increase in plant damage. There was not a strong influence of host plant resistance on grain yield across locations, but foliar insecticide application generally preserved grain yield. Both sorghum hybrids supported an array of different life stages of natural enemies (predators [lady beetle larvae and adults; hoverfly larvae and lacewing larvae] and parasitoids [a braconid and aphelinid]) for both the sprayed and non-sprayed treatments. We found a strong and significant positive relationship between the natural enemies and the M. sorghi infestation. Results suggest that the integration of natural enemies with insecticide control methods in the management of M. sorghi is central to the development of an effective pest management strategy against this invasive pest.