Location: Sugarcane Research2011 Annual Report
1. Resistance to the sugarcane insect (aphid) identified. Economically important virus diseases of sugarcane are transmitted by two aphid species in the United States, and bases of crop resistance have not been identified. Possible resistance mechanisms to include: tolerance, repellency, and host plant suitability for aphid reproduction were explored using five sugarcane varieties currently grown in Louisiana. Based on the results of this study, ARS scientists at the Sugarcane Research Unit, Houma, LA, ranked the varieties from most to least susceptible as L 97-128, LCP 85-384, HoCP 96-540, Ho 95-988, and HoCP 91-555 for the white sugarcane aphid, and L 97-128, LCP 85-384, HoCP 91-555 for the yellow sugarcane aphid. The study demonstrated that the ability to inhibit aphid population growth is the dominant basis of sugarcane’s resistance to both aphid species, and that the variety HoCP 91-555 might be useful as a parent for developing aphid resistant varieties.
2. Post-harvest leaf litter promotes beneficial insect development. The blanket of leaf litter generated during the mechanical harvest of green cane can reduce the yields of the subsequent ratoon sugarcane in Louisiana if not removed. Although research has shown that this litter must be removed, its impact on ants, earwigs, ground beetles, and spiders – all important predators of the sugarcane borer - has not been determined. After four years of sampling, ARS scientists at the Sugarcane Research Unit, Houma, LA, concluded that the litter enhances predator numbers when compared to the recommended practice of burning to completely remove the litter. Relocating the litter blanket by mechanically brushing from the row top to the row sides had an intermediate effect on both crop yield and predator number suggesting that this strategy could be a viable alternative to burning to minimize the impact on crop yield while encouraging increases in predator numbers thereby further reducing the need for insecticide application to control the sugarcane borer.
White, W.H., Hale, A.L., Veremis, J.C., Tew, T.L., Richard Jr, E.P. 2011. Registration of two sugarcane germplasm clones with antibiosis to the sugarcane borer (Lepidoptera: Crambidae). Journal of Plant Registrations. 5(2):248-253.