Central Oregon Potato Extension Program, 2015

Series/Report Number: COARC2015

Abstract: Aphids, tuberworm moths, potato psyllids, and beet leafhoppers were collected and counted weekly in Jefferson County from June 23 to September 9, 2015. Counts were conducted to monitor pest populations and assess potential risk of disease transmission. Collection methods included fifteen water pans for aphid collection, 15 delta traps for potato tuberworm moth, and 15 yellow sticky traps each for psyllid and beet leafhopper. Weekly findings were distributed to growers, fieldmen and industry representatives through reports and website postings. Aphid numbers were low during the first week of monitoring followed by a spike for 2 weeks into a moderately high level at the end of June. Numbers then remained low until rising in August and continued at a high level until trap removal on September 9, 2015. In contrast to 2014, potato tuberworm moths were detected only sporadically and in low numbers during two weeks in August. Potato psyllids were present in increasing numbers starting the week of August 5 until vine kill. Specimens were tested for Lso (Candidatus Liberibacter solanacearum) and all tested negative. Beet leafhoppers were included in the 2015 protocol for the first time in the history of this project and were found mostly in single digit numbers. Specimens trapped after August 5th were tested for the presence of BLTVA phytoplasma and all tested negative. Early blight prediction modeling and crop water use data provided helpful information for seed potato management and weekly monitoring continues to be a significant source of information for integrated pest management in central Oregon potato fields.