Comparative Effectiveness of Bacillus Thuringiensis and Lannate against Spodoptera Littoralis

Application of Dipel 2x at a rate of 250 g/g was effective against the larvae of Spodoptera littoralis (1st to 4th instars), while larvae in older stages (5th and 6th instars) were more resistant. Lannate was highly effective against either young or old larvae. The addition of potassium carbonate to Dipel increased the larval mortality. In Sharkia governorate, the yield of soybean increased significantly when the infested areas were treated once by either Dipel 2x or Lannete with 1.113 fold increase compared with the control. In Monoufia governorate, an obvious increase in soybean yield was also recorded when soybeans were treated three times with Dipel 2x or Lannete but the fold of increase was 2.031 -2.066 times compared to the control. This difference in yield give a higher net profit to the farmer exceeding the costs of spray applications.