Population dynamics of the Colorado potato beetle in an agroecosystem with tomatoes and potatoes with management implications to processing tomatoes

Abstract

We evaluated the population dynamics of Colorado potato beetle in processing tomatoes and potatoes using immigration profiles, density through time, rates of development and survivorship. We also evaluated the beetle's influence on yield of processing cultivars. Colorado potato beetle immigrated into both crops. The first available crop had the earliest immigration event and higher immigrating adult and egg mass densities. Length of time that overwintering adults spent in the field, and duration of oviposition, were more closely related to accumulated degree days than time of immigration. Later in the season there was a trend toward fewer eggs per egg mass from overwintered adults. Rates of development suggested that large larvae developed more quickly in potatoes in 1998, but not in 2000, and small larvae developed at similar rates in either crop. Egg-to-adult survivorship ranged from 0.02 to 0.06, even though initial egg densities varied by approximately an order of magnitude. Survivorship varied more between years than between crops. Colorado potato beetle did not influence yield of processing tomatoes. Our field studies estimated similar life table parameters and population dynamics of Colorado potato beetle in two solaneaceous crops, and concurred with laboratory bioassays in the literature suggesting that this beetle has the potential to achieve similar fitness on both tomatoes and potatoes. However, beetle densities did not influence yield, and thus may have little affect on pest management in processing tomato cultivars.