Susceptibility pattern and development of resistance in the diamondback moth, Plutella xylostella L, to Bacillus thuringiensis Berl var kurstaki in India

✍ Scribed by Muthugounder Mohan; Govind T Gujar

• Publisher: John Wiley and Sons
• Year: 2000
• Tongue: English
• Weight: 116 KB
• Volume: 56
• Category: Article
• ISSN: 1526-498X
• DOI: 10.1002/(sici)1526-4998(200002)56:2<189::aid-ps95>3.0.co;2-t

✦ Synopsis

Base-line susceptibility for six-day-old larvae of the diamondback moth, Plutella xylostella, against Bacillus thuringiensis var kurstaki (Biobit 1 ) was studied by a cabbage leaf disc dip bioassay technique. Diamondback moth from 13 locations in seven different states spread over a distance of about 3000 km longitudinally was used for these studies. Forty-eight-hour LC 50 values varied from 1.0 to 10.97 mg AI litre À1 . Further investigations on the development of resistance under laboratory conditions showed an increase in LC 50 from 2.76 (for unselected F 1 generation) to 5.28 mg AI litre À1 (for selected F 9 generation), using a selection concentration of 6.4 mg AI litre À1 . This suggested a possibility of the development of resistance under ®eld conditions if there were to be extensive and indiscriminate use of B thuringiensis. These ®ndings are discussed in relation to integrated pest management and the mechanisms of resistance in resistance management tactics.