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A C Bartlett

Publications and source records attributed to A C Bartlett.

6 recordsLinked to original sources
PubMed2001

Genetics of pink bollworm resistance to Bacillus thuringiensis toxin Cry1Ac.

Laboratory selection increased resistance of pink bollworm (Pectinophora gossypiella) to the Bacillus thuringiensis toxin Cry1Ac. Three selections with Cry1Ac in artificial diet increased resistance from a low level to >100-fold relative to a susceptible strain. We used artificial diet bioassays to test F1 hybrid progeny from reciprocal crosses between resistant and susceptible strains. The similarity between F1 progeny from the two reciprocal crosses indicates autosomal inheritance of resistance. The dominance of resistance to Cry1Ac depended on the concentration. Resistance was codominant at a low concentration of Cry1Ac, partially recessive at an intermediate concentration, and completely recessive at a high concentration. Comparison of the artificial diet results with previously reported results from greenhouse bioassays shows that the high concentration of Cry1Ac in bolls of transgenic cotton is essential for achieving functionally recessive inheritance of resistance.

Animals↗
PubMed1993

Characterization of differences between whiteflies using RAPD-PCR.

The B biotype of the sweetpotato whitefly, Bemisia tabaci (Gennadius) has caused over $200 million in crop damage in the US during 1992. The taxonomic classification of the A and B biotypes of B. tabaci is unclear. We used RAPD-PCR to demonstrate DNA differences between the A and B biotypes of this insect. All twenty of the RAPD primers tested distinguished readily between the biotypes. DNA extracted from individual eggs and nymphs showed identical differences. RAPD-based genetic similarity statistics indicate that these two biotypes of B. tabaci were no more similar to each other than to two other whitefly species: bayberry whitefly (Parabemisia myricae) or bandedwinged whitefly (Trialeurodes abutilonea). These results indicate that RAPD-PCR may be useful in distinguishing closely related organisms, but may not be useful in determining higher classification of insects. Before the taxonomic status of B. tabaci biotypes A and B can be determined, results from other genetic, morphological and physiological examinations will have to be compared.

Animals↗