B.T. Toxins Studied

Resistance to Bt toxins.

Sustaining the Efficacy of Bt Toxins

In 1997 corn, cotton and potato cultivars that produce insecticidal proteins were grown on more than five million acres of US farmland. The acreage dedicated to these cultivars is likely to increase dramatically in the next twoto-five years. The use of these cultivars decreases the use of broad spectrum insecticides, especially in cotton and potato production. The toxin gene is derived from the...

Nutrition affects insect susceptibility to Bt toxins

Pesticide resistance represents a major challenge to global food production. The spread of resistance alleles is the primary explanation for observations of reduced pesticide efficacy over time, but the potential for gene-by-environment interactions (plasticity) to mediate susceptibility has largely been overlooked. Here we show that nutrition is an environmental factor that affects susceptibil...

Many roads to resistance: how invertebrates adapt to Bt toxins.

The Cry family of Bacillus thuringiensis insecticidal and nematicidal proteins constitutes a valuable source of environmentally benign compounds for the control of insect pests and disease agents. An understanding of Cry toxin resistance at a molecular level will be critical to the long-term utility of this technology; it may also shed light on basic mechanisms used by other bacterial toxins th...

Binding and Oligomerization of Modified and Native Bt Toxins in Resistant and Susceptible Pink Bollworm

Insecticidal proteins from Bacillus thuringiensis (Bt) are used extensively in sprays and transgenic crops for pest control, but their efficacy is reduced when pests evolve resistance. Better understanding of the mode of action of Bt toxins and the mechanisms of insect resistance is needed to enhance the durability of these important alternatives to conventional insecticides. Mode of action mod...