Decreased larval feeding and weight of the monarch butterfly, Danaus plexippus L., have been detected after 4 d of exposure in the laboratory to a high density of Bacillus thuringiensis (Bt)-expressing anthers. One hypothesis is that larvae exposed to Bt anthers exhibit increased wandering, resulting in less feeding and lower weight gain. To test this hypothesis, 2-d-old monarch butterfly larva...

To compare, in a retrospective study, biochemical failure-free survival (bFFS) and overall survival (OS) in low-risk and intermediate-risk prostate cancer patients who received brachytherapy (BT) (either low-dose-rate brachytherapy [LDR-BT] or high-dose-rate brachytherapy with external beam radiation therapy [HDR-BT+EBRT]) versus external beam radiation therapy (EBRT) alone. Patient data were o...

53 The microbial insecticide, Bacillus thuringiensis (Bt), has become the mainstay of non-chemical control of 54 Lepidopteran pests, either as sprays or through the incorporation of Bt toxins into transgenic crops. Given 55 the wide use of Bt, it is striking that currently only one pest species, Plutella xylostella, has been reported 56 to have developed significant resistance to Bt outside the...

The sustainable deployment of resistant crop varieties is a critical issue for the implementation of biotechnology in crop pest management. Feeding, biomass accumulation, and mortality were evaluated for susceptible, insecticide-resistant, and Bacillus thuringiensis (Bt) Cry 3A-selected Colorado potato beetle ( Leptinotarsa decemlineata Say) (Coleoptera, Chrysomelidae) larvae fed on: cultivated...

Transgenic crops producing Bacillus thuringiensis (Bt) toxins kill some key insect pests and thus can reduce reliance on insecticides. Widespread planting of such Bt crops increased concerns that their usefulness would be cut short by rapid evolution of resistance to Bt toxins by pests. Pink bollworm (Pectinophora gossypiella) is a major pest that has experienced intense selection for resistanc...

We define the bounded jump of A by A = {x ∈ ω | ∃i ≤ x[φi(x) ↓ ∧ Φ φi(x) x (x)↓]} and let A denote the n-th bounded jump. We demonstrate several properties of the bounded jump, including that it is strictly increasing and order preserving on the bounded Turing (bT ) degrees (also known as the weak truth-table degrees). We show that the bounded jump is related to the Ershov hierarchy. Indeed, fo...

Transgenic crops producing Bacillus thuringiensis (Bt) toxins for insect pest control have been successful, but their efficacy is reduced when pests evolve resistance. Here we review the definition of field-evolved resistance, the relationship between resistance and field control problems, the theory underlying strategies for delaying resistance, and resistance monitoring methods. We also analy...

A 6-yr Þeld study assessed the long-term impact of Bt cotton producing the Cry1Ac -endotoxin on 22 taxa of foliar-dwelling arthropod natural enemies inArizona. No chronic, long-term effects of Bt cotton were observed over multiple generations of nontarget taxa. Zero-2 taxa declined signiÞcantly in unsprayed Bt compared with non-Bt cotton each year. In contrast, positive control studies showed t...

We used a mathematical model with processes reflecting larval mortality resulting from feeding on cross-pollinated ears or Bt ears of corn to analyze the risk of evolution of Cry-toxin resistance in Ostrinia nubilalis (Hübner). In the simulations, evolution of resistance was delayed equally well by both seed mixtures and blocks with the same proportion of refuge. Our results showed that Bt-poll...