Submitted to: Annals of the Entomological Society of America
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/9/2011
Publication Date: 7/14/2011
Citation: Akbar, W., Showler, A.T., Beuzelin, J.M., Reagan, T.E., Gravois, K.A. 2011. Evaluation of aphid resistance among sugarcane cultivars in Louisiana. Annals of the Entomological Society of America. 104(4):699-704. Interpretive Summary: In Louisiana, sugarcane is attacked by two species of aphids, both of which can spread viruses. Five commonly-used sugarcane cultivars were studied in the field to determine which cultivars are susceptible to the aphids, and which ones are resistant. We found that the cultivars L 97-128 and Ho 95-988 are susceptible, LCP 85-384 is moderate, and HoCP 91-555 and HoCP 96-540 are resistant based on aphid populations found on each.
Technical Abstract: Sugarcane, interspecific hybrids of Saccharum spp., in Louisiana is colonized by two aphid species, the sugarcane aphid, Melanaphis sacchari (Zehntner), and the yellow sugarcane aphid, Sipha flava (Forbes). Five sugarcane cultivars, LCP 85-384, HoCP 91-555, Ho 95-988, HoCP 96-540, and L 97-128, representing more than 95% of Louisiana’s sugarcane production acreage in 2005, were evaluated in replicated field experiments for natural infestations of the two aphid species. Data collected April through August for two years on plant cane (2007) and the first ratoon crop (2008) indicated that both cultivar and sampling time influenced aphid numbers. Each year, infestations were minimal in April, peaked during June and July, and crashed thereafter. In plant cane, L 97-128 was the most susceptible cultivar with highest aphid numbers (65/plant) recorded in the third week of July 2007. HoCP 91-555 had the lowest aphid infestations throughout the season during both years. Ratoon Ho 95-988 had maximum aphid infestations on all sampling dates except in early July when L 97-128 had the highest numbers of aphids. Melanaphis sacchari was more abundant than S. flava on all sampling dates for both plant cane and first ratoon crop regardless of cultivar. Based on this study, L 97-128 and Ho 95-988 are susceptible, LCP 85-384 moderately resistant, and HoCP 91-555 and HoCP 96-540 are resistant cultivars. Results from this field study also corroborate that HoCP 91-555 is resistant to the aphids as previously reported from greenhouse experiments, and suggest that this cultivar can be useful as a source of resistance in cultivar development programs.