|Alvarez, J. - UNIVERSITY OF ID,ABERDEEN|
Submitted to: American Journal of Potato Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 8, 2004
Publication Date: January 1, 2005
Citation: Novy, R.G., Alvarez, J.M. 2005. Resistance to wireworm in the progeny of a tri-species somatic hybrid. American Journal of Potato Research. 82(1):84-85. Technical Abstract: Wireworms (Coleoptera:Elateridae), the soil-dwelling larval stages of click beetles, are the most important soil-dwelling pest of potato. Wireworms feeding upon seed pieces during the spring and their subsequent burrowing into developing tubers can result in crop losses of 5-25%. Growers in the U.S. rely on a few registered organophosphate and carbamate insecticides, which are not always effective for control of wireworms; their continued use in the future is questionable in that the EPA is reviewing their use on potato and may not re-register these insecticides. An important component of many successful IPM programs is host plant resistance. A complex somatic hybrid (Solanum etuberosum + haploid Gp. Tuberosum x S. berthaultii hybrid) was crossed successfully to cultivated potato and its 1st-3rd generation progeny were evaluated in Idaho over a two-year period for wireworm resistance. Reduction in tuber quality due to wireworm was expressed as percent of tubers with one or more wireworm-induced holes and as the mean number of holes per tuber. Tubers from breeding selections were evaluated and compared for wireworm damage to Russet Burbank tubers treated with insecticides in the same field trial. Several progeny of the somatic hybrids exhibited a reduction in wireworm damage that was better or comparable to chemical controls. Analysis of tubers for total tuber glycoalkaloids (TTG) indicated that the highest levels of resistance were found in material with >20 mg/100 g FWB. However, wireworm resistant clones also were identified with acceptable TTG, indicating that the types of glycoalkaloids present in the tuber---not just TTG, may be important in conferring wireworm resistance.