Insect pests are responsible for human suffering and financial losses worldwide. New and environmentally safe insecticides are urgently needed to cope with these serious problems. Resistance to current insecticides has resulted in a resurgence of insect pests, and growing concerns about insecticide toxicity to humans discourage the use of insecticides for pest control. The small market for insecticides has hampered insecticide development; however, advances in genomics and structural genomics offer new opportunities to develop insecticides that are less dependent on the insecticide market. This review summarizes the literature data that support the hypothesis that an insect-specific cysteine residue located at the opening of the acetylcholinesterase active site is a promising target site for developing new insecticides with reduced off-target toxicity and low propensity for insect resistance. These data are used to discuss the differences between targeting the insect-specific cysteine residue and targeting the ubiquitous catalytic serine residue of acetylcholinesterase from the perspective of reducing off-target toxicity and insect resistance. Also discussed is the prospect of developing cysteine-targeting anticholinesterases as effective and environmentally safe insecticides for control of disease vectors, crop damage, and residential insect pests within the financial confines of the present insecticide market.

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'Aphid Alert' was the name used to identify a series of research and outreach initiatives undertaken from 1992 to 2003, and in some instances since, to address potato virus problems in seed potato production in the Northern Great Plains (NGP) of the USA, in particular northwestern Minnesota and eastern North Dakota. Aphid Alert was adopted from the name of a pest management advisory newsletter sent to Minnesota and North Dakota seed potato growers in 1994, and again from 1998 to 2003. The name found popular acceptance and was applied, even retroactively, to a series of related research/outreach activities. This chapter focused primarily on the areawide aphid-trapping network operated by the University of Minnesota from 1992 to 1994, and again from 1998 to 2003. Data presented here on potato seed lot rejections due to potato viruses were provided by the Minnesota Department of Agriculture Seed Potato Certification Program. Data presented here on aphids (reported as numbers or percentages of total captures) are from the subset of traps that were located in the NGP portion of the network.

Pyrethrum [Chrysanthemum cinerariifolium (Trevir.) Vis.] is an important "green pesticide" crop widely used for insect control on plants and for humans. Pyrethrum flowers have the highest Pyrethrin I/Pyrethrin II ratio (%Py) and are harvested at specific stages to maximize yield. Selection for correlative early seed germination and flowering in first year pyrethrum seedlings is challenging and has not been accomplished previously. The breeding objectives for this study were to sample a wide germplasm base to select for rapid generation cycling (RGC) traits of early and high germination in Weeks 1-4, earliness of visible bud date (VBD) and flowering, accelerated growth, high leaf unfolding rates per week, number of shoots, and %Py in the 1st-12th flowers. Seven seed lots were evaluated for germination rate and timing (N = 141,120 seeds) in Year 1 for RGC traits. Seedling germination was recorded weekly with toothpicking to identify germination weeks with successive selection occurring at transplanting. Grand mean percentage germination was low (24.5%), whereas individual seed lots varied (18.4-38.9%). Seedling death was 0.0-6.8%. On average, it took 34-39 wk to reach VBD and an additional 3-4 wk to flower. Thus, flowering in <1 yr without vernalization is a new trait (annualized perennial) selected in this crop. Germination week was significantly correlated with VBD and flowering dates and is an important trait to use for selecting early-flowering genotypes in plug trays. Pyrethrum breeding programs could select the earliest germinating seedlings (Weeks 1-4 after sowing) at transplanting to enhance the likelihood of selecting early-flowering genotypes in the first year and provide an additional year of harvest to increase yield.

This chapter discusses the various aspects of aphid management in seed potatoes, including the advantages of seed certification, the danger of aphids transmitting potato viruses, use of economic thresholds and mathematical modelling. It focuses on the integrated pest management tactics (monitoring aphid flight, chemical, biological and cultural control, and use of pest resistant cultivars) available against aphids of potatoes.