|MUSTAFA, T - Washington State University|
|Cooper, Rodney - William|
|Swisher Grimm, Kylie|
|ZACK, R - Washington State University|
|Munyaneza, Joseph - Joe|
Submitted to: Environmental Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/4/2014
Publication Date: 4/1/2015
Citation: Mustafa, T., Horton, D.R., Cooper, W.R., Swisher, K.D., Zack, R.S., Munyaneza, J.E. 2015. Interhaplotype fertility and host effects of potato and bittersweet nightshade on selected reproductive traits of three haplotypes of Bactericera cockerelli (Hemiptera: Triozidae). Environmental Entomology. 44:300-308.
Interpretive Summary: Potato psyllid is the insect vector of zebra chip, a new and economically important disease of potato in the United States, including the Pacific Northwest, where over 50% of U. S. potatoes are grown. Researchers at USDA-ARS Wapato in Washington, in collaboration with scientists at Washington State University, assessed how rapidly this insect pest reproduces when reared on potato or bittersweet nightshade, an important perennial weed commonly found near potato crops in the Pacific Northwest. It was determined that the potato psyllid reproduces better on bittersweet nightshade than potato, which may lead to production of large populations of this insect pest moving to potato crops and increasing the risk of zebra chip damage in this major potato growing region. This information will help potato producers minimize damage caused by zebra chip by focusing on the management of bittersweet nightshade to reduce potato psyllid populations.
Technical Abstract: Potato psyllid, Bactericera cockerelli (Šulc) (Hemiptera: Triozidae), is a serious pest of solanaceous crops in North and Central America and New Zealand. This insect vectors the bacterium that causes zebra chip disease of potato. Four distinct genetic populations, or haplotypes, of B. cockerelli have been identified. The haplotypes are associated with different geographic regions, but co-occur in potato fields in the Pacific Northwest of the United States. Solanaceous weeds, including the perennial Solanum dulcamara (bittersweet nightshade), may provide refuge for psyllid populations which then migrate to potato crops. This study tested whether fecundity and fertility (% egg hatch) of potato psyllid were affected by host plant (S. dulcamara or potato) and whether these reproductive traits were similar among the three most common psyllid haplotypes in the Pacfic Northwest: Northwestern, Central, and Western. We additionally examined whether matings between psyllid haplotype affected sperm transfer and egg hatch rates. Fecundity differed significantly among the three haplotypes, with an average lifetime fecundity of 1050, 877, and 629 eggs for Northwestern, Western, and Central females, respectively. Egg hatch was significantly reduced in psyllids reared on bittersweet nightshade (61.9%) versus potato (81.3%). Adult psyllids lived longer on nightshade than on potato, averaging 113.9 and 108.4 d on nightshade and 79.0 and 85.5 d on potato for males and females, respectively. However, the longer life span of psyllids on nightshade than potato failed to lead to higher fecundity, because females on nightshade ended egglaying well before death, unlike those on potato. Lastly, females of the Northwestern haplotype failed to produce viable eggs when mated by males of either the Western or Central haplotypes. Information from these studies will help growers develop more effective management strategies for zebra chip and its insect vector.