Development of resistance to the insecticidal toxins from Bacillus thuringiensis (Bt) in insects is the major threat to the continued success of transgenic Bt crops in agriculture. The fitness of Bt-resistant insects on Bt and non-Bt plants is a key parameter that determines the development of Bt resistance in insect populations. In this study, a comprehensive analysis of the fitness of Bt-resi...

The development of pest resistance to transgenic crop plants producing insecticidal toxins from Bacillus thuringiensis Berliner (Bt) poses a major threat to their sustainable use in agriculture. "Pyramiding" two toxins with different modes of actions in the same plant is now being used to delay the evolution of resistance in the insects, but this strategy could fail if a single gene in a pest c...

Transgenic crops producing Bacillus thuringiensis (Bt) proteins have become a primary tool in pest management. Due to the intensive use of Bt crops, resistance of the fall armyworm, Spodoptera frugiperda, to Cry1F maize has occurred in Puerto Rico, Brazil, and some areas of the southeastern U.S. The sustainability of Bt crops faces a great challenge because the Cry1F-maize resistant S. frugiper...

Insect pest complex, cotton leaf curl disease and weeds pose major threat to crop production worldwide, including Pakistan. To address these problems, in the present study a triple gene construct harboring Cry1Ac, Cry2Ab, and EPSPS cassettes has been developed for plant specifically in cotton transformation against lepidopteron insect-pests and weeds. Nicotiana benthamiana (tobacco) was used as...

The tobacco budworm, Heliothis virescens (F.) (Lepidoptera: Noctuidae), is one of the most important pests of cotton, Gossypium hirsutum L, that has become resistant to a wide range of synthetic insecticides. CrylAc-expressing cotton has proven its effectiveness against this insect since its introduction in North America in 1996. However, the constant exposure of tobacco budworm to this protein...

The biological control function provided by natural enemies is regarded as a protection goal that should not be harmed by the application of any new pest management tool. Plants producing Cry proteins from the bacterium, Bacillus thuringiensis (Bt), have become a major tactic for controlling pest Lepidoptera on cotton and maize and risk assessment studies are needed to ensure they do not harm i...

Transgenic corn producing Cry1Ac toxins from Bacillus thuringiensis (Bt) provides effective control of Asian corn borer, Ostrinia furnacalis (Guenée), and thus reduces insecticide applications. However, whether Bt corn exerts undesirable effects on non-target arthropods (NTAs) is still controversial. We conducted a 2-yr study in Shangzhuang Agricultural Experiment Station to assess the potentia...

Gene pyramiding is an efficient approach for the genetic improvement of multiple agronomic traits simultaneously. In this study, we pyramided two foreign genes, cry1Ac driven by the rice Actin I promoter, and lysine-rich protein (LRP), driven by the endosperm-specific GLUTELIN1 (GT1) promoter, into the elite indica cultivar 9311. These two genes were chosen in an attempt to enhance insect-resis...

A rape seed pollen-based diet was developed and found to be suitable for use in a dietary exposure assay for Propylea japonica. Using the diet, we established and validated a dietary exposure assay by using the protease inhibitor E-64 as positive control. Dose-dependent responses were documented for all observed life-table parameters of P. japonica including survival, pupation and eclosion rate...