| frequency of cry1f non-recessive resistance alleles in north carolina field populations of spodoptera frugiperda (lepidoptera: noctuidae). | fall armyworm, spodoptera frugiperda (j.e. smith) (lepidoptera: noctuidae), is a target species of transgenic corn (zea mays l.) that expresses single and pyramided bacillus thuringiensis (bt) toxin. in 2014, s. frugiperda were collected from a light trap in north carolina, and a total of 212 f1/f2 isofemale lines of s. frugiperda were screened for resistance to bt and non-bt corn. all of the 212 isolines were susceptible to corn tissue expressing cry1a.105 + cry2ab, cry1f + cry1a.105 + cry2ab, ... | 2016 | 27119741 |
| modeling the impact of alternative hosts on helicoverpa zea adaptation to bollgard cotton. | for highly polyphagous cotton, gossypium hirsutum l., pests such as helicoverpa zea (boddie), a substantial portion of the larval population develops on noncotton alternative hosts. these noncotton hosts potentially provide a natural refuge for h. zea, thereby slowing the evolution of resistance to the bacillus thuringiensis berliner (bt)-derived cry1ac protein present in bollgard cotton. here, we demonstrate how the measured contribution of such alternative hosts can be included in estimating t ... | 2006 | 17195681 |
| comparative insecticidal properties of two nucleopolyhedrovirus vectors encoding a similar toxin gene chimer. | laboratory, greenhouse and field studies were conducted to characterize the insecticidal properties of genetically altered forms of autographa californica (speyer) nucleopolyhedrovirus (acnpv) and helicoverpa zea (boddie) npv (hznpv) against selected heliothine species. the altered viruses each contained a chimeric 0.8-kb fragment encoding the insect-specific, sodium channel neurotoxin from the algerian scorpion androctonus australis hector (aait, hence recombinant viruses designated ac-aait and ... | 2000 | 10985018 |
| estimated frequency of nonrecessive bt resistance genes in bollworm, helicoverpa zea (boddie) (lepidoptera: noctuidae) in eastern north carolina. | in summer 2000, adult female bollworm moths, helicoverpa zea (boddie), were collected from light-traps at four locations near the tidewater research station, plymouth, nc. female moths were allowed to lay eggs, and at hatch, 72 larvae from each female were screened for growth rate on normal artificial diet and on diets containing 5.0 microg of either cry1ac or cry2aa bt toxin per milliliter of diet. the growth rate bioassays were performed to isolate nonrecessive bt resistance genes present in f ... | 2003 | 12650356 |
| aventis gets short shrift over release of modified corn. | | 2000 | 11100697 |
| life history traits of helicoverpa zea (lepidoptera: noctuidae) on non-bt and bt transgenic corn hybrids in eastern north carolina. | transgenic varieties of field corn that express the crylab b. thuringiensis (bt) toxin in ear tissue present the potential of reducing ear feeding by the corn earworm, helicoverpa zea (lepidoptera: noctuidae), and for reducing the size of populations of the insect infesting other host crops. life history parameters of h. zea feeding on ears of conventional and bt field corn varieties were measured in field plots in eastern north carolina in 1997 and 1998. transformation events investigated were ... | 2001 | 11681693 |
| transgenic crop trial's gene flow turns weeds into wimps. | | 2003 | 12556850 |
| genetic variation for resistance to bacillus thuringiensis toxins in helicoverpa zea (lepidoptera: noctuidae) in eastern north carolina. | to evaluate resistance to bacillus thuringiensis berliner (bt) toxins, adult female bollworms, helicoverpa zea (boddie) (lepidoptera: noctuidae), were collected from four light trap locations in two eastern north carolina counties from august to october during 2001 and 2002. females were allowed to oviposit, and upon hatching, 24 neonates from each female (f1 lines) were screened for survival and growth rate on each of three diets: non-bt diet, diet containing 5.0 microg/ml cry1ac toxin, or diet ... | 2006 | 17066814 |
| the lack of effect of low temperature and high turbidity on operational bacillus thuringiensis subsp. israelensis activity against larval black flies (diptera: simuliidae). | black fly suppression programs are conducted across a wide range of environmental conditions, targeting a variety of pest species with diverse life histories. operational applications of vectobac 12as (bacillus thuringiensis subsp. israelensis) were conducted during times characterized by water temperature and turbidity extremes. applications were conducted in the yellow river in central wisconsin targeting simulium annulus and s. johannseni when water temperatures were 1-2 degrees c. applicatio ... | 2012 | 22894128 |