An agent-based model of insect resistance management and mitigation for Bt maize: a social science perspective.

Background: Farmers around the world have used Bt maize for more than two decades, delaying resistance using a high-dose/refuge strategy. Nevertheless, field-evolved resistance to Bacillus thuringiensis (Bt) toxins has been documented. This paper describes a spatially explicit population genetics model of resistance to Bt toxins by the insect Ostrinia nubilalis and an agent-based model of farmer adoption of Bt maize incorporating social networks.

A Probabilistic Bio-Economic Assessment of the Global Consequences of Wheat Leaf Rust.

This study provides a bio-economic assessment of the global climate suitability and probabilistic crop-loss estimates attributable to wheat leaf rust. We draw on a purpose-built, spatially explicit, ecoclimatic suitability model for wheat leaf rust to estimate that 94.4% of global wheat production is vulnerable to the disease.

The value of insect management to US maize, soybean and cotton farmers.

Background: Most US maize, soybean and cotton farmers use Bt crops, insecticidal seed treatments, soil-applied insecticides, and foliar sprays to manage insect pests. Given the global economic importance of these crops, we examine farmer benefits of this insecticide use. Using a telephone survey, we document pest management practices and concerns, estimate adoption and farmer perceived values for these practices, and determine factors besides yield and cost that impact adoption and perceived value.

Do farmers manage weeds on owned and rented land differently? Evidence from US corn and soybean farms.

Background: It has been frequently argued that growers have less incentive to manage the evolution and spread of herbicide-resistant weeds on leased than on owned land. This is because resistance management provides long-term rather than short-term benefits that operators may be less assured of capturing on land they do not own. Yet, empirical evidence supporting this argument has been lacking.

Returns to food and agricultural R&D investments in Sub-Saharan Africa, 1975-2014.

Research-enabled growth in agricultural productivity is pivotal to sub-Saharan Africa's overall economic growth prospects. Yet, investments in research and development (R&D) targeted to many national food and agricultural economies throughout Africa are fragile and faltering. To gain insight into what could be driving this trend, this article updates, summarizes and reassesses the published evidence on the returns to African agricultural R&D.

Recruitment and Retention of Volunteers in a Citizen Science Network to Detect Invasive Species on Private Lands.

Volunteer citizen monitoring is an increasingly important source of scientific data. We developed a volunteer program for early detection of new invasive species by private landowners on their own land. Early detection of an invasive species, however, subjects the landowner to the potentially costly risk of government intervention to control the invasive species.

Early Detection and Mitigation of Resistance to Bt Maize by Western Corn Rootworm (Coleoptera: Chrysomelidae).

Transgenic Bt maize that produces less than a high-dose has been widely adopted and presents considerable insect resistance management (IRM) challenges. Western corn rootworm, Diabrotica virgifera virgifera LeConte, has rapidly evolved resistance to Bt maize in the field, leading to local loss of efficacy for some corn rootworm Bt maize events. Documenting and responding to this resistance has been complicated by a lack of rapid diagnostic bioassays and by regulatory triggers that hinder timely and effective management responses.

Seeds of change: corn seed mixtures for resistance management and integrated pest management.

The use of mixtures of transgenic insecticidal seed and nontransgenic seed to provide an in-field refuge for susceptible insects in insect-resistance-management (IRM) plans has been considered for at least two decades. However, the U.S.