2007 Annual Report
• Hull hardness in rough rice is a barrier to insect attack. In most cereal grains kernel hardness is correlated with resistance to damage from the lesser grain borer, however, the hull of rough rice could offer some level of protection. Scientists at the Grain Marketing and Production Research Center in Manhattan, KS, exposed young larvae of the lesser grain borer on different rice types with solid hulls, cracked hulls, and brown rice with the hull removed, and analyzed kernels for hardness and amylose content. More larvae entered the kernel and developed to the adult stage when the hulls were cracked, but there was no differences in kernel hardness, amylose content, or hulled rice that were related to larval development. This study shows that sound hulls are a barrier to lesser grain borer larvae, and that the characteristics of the kernel may not be important in determining risk or susceptibility to this insect. This research addresses National Program 304, Component IV Crop Protection and Quarantine, Stored Product Insects, Section E. Biology and Ecology of Stored Product Insects: Determining how nutritional factors and commodity quality can affect stored product pest population dynamics and pest management decisions.
• Insect growth regulator methoprene affects eggs of the lesser grain borer. One of the insecticides used to control the lesser grain borer on stored rice is the insect growth regulator methoprene, and while this insecticide limits development of immature insects, we have limited information regarding direct toxicity to eggs of the lesser grain borer. Scientists at the Grain Marketing and Production Research Center in Manhattan, KS, exposed eggs of the lesser grain borer on filter paper and on rice treated with methoprene, and also exposed adults on treated rice. Mortality of eggs increased as the concentration of methoprene on filter paper increased, and eggs exposed directly on rice either failed to hatch, or larvae died before they could penetrate the hull, or died inside the kernel and did not reach the adult stage. When adult females were exposed on rice treated with methoprene, egg-laying was reduced. Results show that eggs of the lesser grain borer are extremely sensitive to methoprene, and it could be used effectively in management programs that are targeted toward this insect. This research addresses National Program 304, Component IV Crop Protection and Quarantine, Stored Product Insects, Section G. Development of New and Improved Control Technologies: Determining new control technologies and improving existing control technologies, including combined use of different control technologies.
• Rice varieties vary in susceptibility to stored-grain insects. Scientists at the Grain Marketing and Production Research Center in Manhattan, KS, in cooperation with scientists at the University of Arkansas in Fayetteville, AR, exposed adult lesser grain borers and rice weevils on several cultivars of long-grain and medium-grain rice from several growing locations. Progeny production of both species and resultant feeding damage varied with both rice types and with the specific cultivar and location, but the physical characters we measured were not correlated with progeny production. Location and cultivar were important in determining the susceptibility of rough rice to the lesser grain borer and the rice weevil, but this susceptibility probably relates more to the condition of the exterior hull than the physical characteristics of the kernel itself. This research addresses National Program 304, Crop Protection and Quarantine, Component IV Stored Product Insects, Section E. Biology and Ecology of Stored Product Insects: Determining how nutritional factors and commodity quality can affect stored product pest population dynamics and pest management decisions.
Toews, M.D., Campbell, J.F., Arthur, F.H., Ramaswamy, S.B. 2006. Outdoor flight activity and immigration of Rhyzopertha dominica into seed wheat warehouses. Entomologia Experimentalis et Applicata 121: 73-85.
Tilley, D.R., Casada, M., Arthur, F.H. 2007. Heat treatment for disinfestation of empty grain storage bins. Journal of Stored Products Research. 43:221-228.
Mohandass, S.M., Arthur, F.H., Zhu, K.Y., Throne, J.E. 2007. Biology and management of Plodia interpunctella (Lepidoptera: Pyralidae) in stored products. Journal of Stored Products Research 43: 302-311.
Lord, J.C. 2006. Detection of Mattesia oryzaephili (Neogregarinorida: Lipotrophidae) in grain beetle laboratory colonies with an enzyme-linked immunosorbent assay. Journal of Invertebrate Pathology 94: 74-76.
Arthur, F.H., Bautista, R.C., Siebenmorgen, T.J. 2007. Influence of growing location and cultivar on Rhyzopertha dominica (F.) and Sitophilus oryzae (L.) infestation of rough rice. Insect Science 14: 231-239.
Butts, C.L., Dorner, J.W., Brown, S.L., Arthur, F.H. 2006. Aerating farmer stock peanut storage in the southeastern u.s.. Transactions of the ASAE. 49(2):457-465.
Chanbang, Y., Arthur, F.H., Wilde, G.E., Throne, J.E. 2007. Efficacy of diatomaceous earth to control Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae) in rough rice: Impacts of temperature and relative humidity. Crop Protection. 26(7): 923-929. Doi: http://dx.doi.org/10.1016/j.cropro.2006.08.009.
Lord, J.C. 2007. Enhanced efficacy of Beauveria bassiana for the red flour beetle, Tribolium castaneum, with reduced moisture. Journal of Economic Entomology 100: 1071-1074.