| Autor: |
Manchikatla, Saisri, Ningthoujam, Kennedy, Pathak, Mahesh, Singh, Akoijam Ratankumar |
| Zdroj: |
Egyptian Journal of Biological Pest Control; December 2023, Vol. 33 Issue: 1 |
| Abstrakt: |
Background: Cabbage butterfly, Pieris brassicae(Linnaeus) (Lepidoptera: Pieridae), is one of the most important pests of cabbage and other cruciferous crops and accounts for > 40% yield reduction in the crops. An investigation on the baseline susceptibility of P. brassicaeto Bacillus thuringiensis(Bt) Cry toxins in Meghalaya was evaluated for future exploitation in Btresistance monitoring. Two different Cry toxins, BtCry1C and Cry2Ab, were screened against 11 different field populations of P. brassicaefrom the state of Meghalaya. LC50was evaluated based on the response of larval mortality of P. brassicaeusing the leaf-dip bioassay method. Results: The baseline-susceptibility tests conducted on P. brassicaein 11 different field populations from Meghalaya revealed that Smit population strains seemed to show less tolerance to both the BtCry toxins (Cry1C and Cry2Ab). Compared to the Cry1C toxin, Cry2Ab was found more potent against P. brassicae. The median lethal concentrations, LC5072 h, varied from 0.535 to 1.725 µg/ml for Cry2Ab and 0.546–1.803 µg/ml for Cry1C toxin. The screening using leaf-dip bioassay resulted in a tolerance ratio of 3.3-fold and 3.2-fold for Cry1C and Cry2Ab, respectively. The most tolerant strains of P. brassicaefrom Umiam and Pepbah regions were observed to show discriminating concentrations of 19.30 µg/ml for Cry1C and 24.03 µg/ml for Cry2Ab (LC99, 72 h). Conclusions: The Cry2Ab toxin was found to be more virulent than Cry1C toxin for P. brassicae. Certain candidate discriminating concentrations for Cry1C and Cry2Ab can be used as benchmarks for future resistance monitoring of P. brassicaeto BtCry toxins. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
|
Full text from SpringerLink