ECOLOGY AND MANAGEMENT OF GRASSHOPPERS AND OTHER INSECT PESTS IN THE NORTHERN GREAT PLAINS
Location: Pest Management Research Unit
Title: INTEGRATION OF A RESISTANT SUGARBEET VARIETY WITH THE INSECT PATHOGENIC FUNGUS METARHIZIUM ANISOPLIAE TO MANAGE THE SUGARBEET ROOT MAGGOT
Submitted to: Sugarbeet Research and Extension Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 1, 2006
Publication Date: April 1, 2006
Citation: Jaronski, S., Campbell Jr, J.E. 2006. Integration of a resistant sugarbeet variety with the insect pathogenic fungus metarhizium anisopliae to manage the sugarbeet root maggot. Sugarbeet Research and Extension Reports. 36: 185-189.
Interpretive Summary: We conducted small plot field trials in 2003 and 2004 in which a sugarbeet-root-maggot-resistant variety, F1015, and a susceptible variety, Beta 3820, were combined with applications of the fungal biocontrol agent, Metarhizium anisopliae. Our goal was to determine whether the fungus would reduce damage (increase yield) to a significantly greater extent in a resistant variety than in a susceptible variety, in the face of heavy insect pressure. Reduction of root damage and improvement in yield due to fungus treatment of small field plots was not significantly greater with the resistant variety than with the susceptible one. Ancillary experiments indicated that there may not have been enough fungus in the insect’s microhabitat for an efficacy, however.
The insect pathogenic fungus, Metarhizium anisopliae, has been under study for the control of Tetanops myopae-formis, the sugarbeet root maggot (SBRM) has not been very effective by itself in the face of the heavy insect pressure that routinely occurs in the northern Red River Valley., esp. in the upper Red River Valley. Integration of a microbial biocontrol agent with other pest management tools may provide economic management of pest damage. approach may be to couple an SBRM resistant sugarbeet with the fungus. We conducted small plot field trials in 2003 and 2004 in which a resistant variety, F1015, and a SBRM susceptible variety, Beta 3820, were combined with applications of M. anisopliae. Our goal was to determine whether the fungus would reduce damage (increase yield) to a significantly greater extent in a resistant variety than in a susceptible variety, in the face of heavy insect pressure. There were no significant differences due to Metarhizium applications in root damage or yield, within variety, in either year, even though there were numerical increases in all categories (except percent sugar in the resistant variety). Differences in root damage and yield were significant between the two varieties. Bioassays of post-treatment soils and determination of Metarhizium colony forming units/g soil indicated that there may not have been enough Metarhizium in the larval microhabitat to produce good efficacy.