Effect of drying conditions on triticale seed germination and rice weevil infestation

Authors: KHEDHER AGHA, MAHMOUD - University Of Baghdad; BUCKLIN, RAY - University Of Florida; LEE, WONSUK - University Of Florida; Mankin, Richard; BLOUNT, ANN - University Of Florida

Submitted to: Transactions of the ASABE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/30/2017
Publication Date: 5/1/2017
Citation: Khedher Agha, M.K., Bucklin, R.A., Lee, W.S., Mankin, R.W., Blount, A.R. 2017. Effect of drying conditions on triticale seed germination and rice weevil infestation. Transactions of the ASABE. 60(2):571-575. https://doi.org/10.13031/trans.12024.
DOI: https://doi.org/10.13031/trans.12024

Interpretive Summary: The combination of high protein content and a soft seed coat makes triticale vulnerable to attack by weevils. Researchers in the Department of Agricultural Machinery and Equipment, University of Baghdad, Baghdad, Iraq, the Department of Agricultural and Biological Engineering, University of Florida, Gainesville, Florida, and the USDA, Agricultural Research Service, Center for Medical, Agricultural, and Veterinary Entomology, Gainesville, Florida, collaborated to investigate whether there were drying treatments that would prevent successful infestation by rice weevils but allow triticale seeds to germinate. This study tested the effects of drying seeds at varying temperatures on seed germination and found adequate rates of germination at all tested temperatures. Rice weevils infested non-dried triticale seeds, but were not observed in temperature-treated grain. The results of this study showed that triticale seed can be dried to moisture contents that effectively controls weevil infestation without significantly affecting germination rate in hot, humid climates.

Technical Abstract: The combination of high protein content and a soft seed coat makes triticale vulnerable to attack by weevils. Drying triticale grain to moisture contents safe for storage can prevent infestation by weevils, but if grain is being stored for seed, high drying temperatures can affect seed germination. Grain can be effectively dried at low temperatures, but low temperature drying is difficult in hot, humid regions such as the Gulf Coast. This study investigated the effects of drying temperatures from 35°C to 45°C on triticale seed germination and found that the were no statistical differences between the germination rates of the seed at any of the drying temperatures and the germination rates of controls. Final moisture contents after drying ranged from 7.9 % wet basis (wb) for 45°C for 48 hours to 9.7% wb for 35°C for 24 hours. New generations of rice weevils appeared in the control samples maintained at 23°C and 13.8 or 13.9 % wb, but were not observed in grain dried at any of the drying treatments. The results of this study showed that triticale seed can be dried to moisture contents that effectively control weevil infestation without significantly affecting germination rate in hot, humid climates.