Fall soil sampling method for predicting spring infestation of white grubs (Coleoptera: Scarabaeidae) in corn and the benefits of clothianidin seed treatment in Virginia

Translocation of the neonicotinoid seed treatment clothianidin in maize

“…These data also provide a potential mechanism to explain a range of field observations from previously published literature. Numerous studies have reported inconsistent yield benefits of NSTs in maize, including finding no advantages of the NST approach when compared to maize seed having no insecticide applied [ 57 – 59 ]. Similarly, our study found no statistical differences in stand count, root ratings, or yield between treated and untreated seed in both years.…”

“…While Bt hybrids largely control damage from the western corn rootworm ( Diabrotica virgifera virgifera LeConte) [ 7 , 8 ], the primary maize pest of Indiana [ 9 ] (recent resistance notwithstanding [ 10 ]), the 1.25 mg/kernel rate is also labeled to control the larval stage of this pest [ 11 , 12 ]. NSTs are also labeled to control a range of other secondary, early season root and seed pests including wireworms [ 13 ], seedcorn maggots [ 14 ], and white grubs [ 15 ]. White grubs preferentially attack the root tissue of young seedlings [ 16 ] and wireworms occasionally burrow into the stems of young seedlings [ 17 ] however, both will readily feed on the germinating seed [ 18 ], the primary site of seedcorn maggot attack [ 14 ].…”

Impacts of neonicotinoid seed treatments on soil-dwelling pest populations and agronomic parameters in corn and soybean in Quebec (Canada)

“…Alford and Krupke [95] reported that less than 1.5% of clothianidin applied to the seeds translocate through the roots and shoots of corn plants under field conditions and that this treatment did not cover the entire window of activity of all soil insect pests. This temporally limited protection from insecticide within the plant could in part explain the variability in yield differences between treated and untreated plants in many field studies [57,58,61].…”

“…In corn, some studies have examined yield differences between treated and untreated seeds [30,53,57,58,59,60,61]; however, the results are inconsistent, with a recent meta-analysis covering 15 years of high dose of neonicotinoids applied to control western and northern corn rootworm in Indiana demonstrating no yield differences [30], while another study spanning 14 years and 91 trials in the southern part of the USA showed a 700 kg/ha higher yield in treated corn [59]. In the northeastern part of Canada, which has different climatic conditions and agronomic practices, no studies have been done to evaluate soil-borne insect pest pressure or the impact of using insecticide seed treatments in corn and soybean.…”

Intersections between neonicotinoid seed treatments and honey bees

“…The predominant neonicotinoids used in seed treatment formulations for grain and oilseed crops are thiamethoxam, its metabolite clothianidin, and imidacloprid. Although these formulations can provide crop protection, particularly from aphids and other sucking insects [9], the economic benefits associated with their use have been difficult to quantify in the major cropping systems where they are used, including maize [10][11][12][13] and soybeans [14,15]. These compounds also carry risks to beneficial insects and non-target areas surrounding fields both during and after planting.…”