CHEMICAL CONTROL OF THE POTATO TUBER MOTH PHTHORIMAEA OPERCULELLA (ZELLER) ON TOBACCO

Y. Dimitrov, T. Vaneva-Gancheva

Abstract: For the purpose of assessing the potential of chemical compounds belonging to different groups (acetamiprid, deltamethrin, imidacloprid and chlorpyrifosethyl + cypermethrin – registered to be used on tobacco in Bulgaria and also indoxacarb and chlorantraniliprole – not registered) to control the attacks of the potato tuber moth Phthorimaea operculella (Zeller) on tobacco, their ovicidal and larvicidal effects have been established under laboratory conditions. Their biological efficiency has also been assessed under field conditions by controlling the extent of the damages caused to the tobacco. Depending on the degree of influence on the eggs, the analyzed substances rank as follows: chlorpyrifosethyl+cypermethrin > deltamethrin > acetamiprid > indoxacarb > imidacloprid > chloranrhaniliprole. Chloranrhaniliprole, chlorpyrifosethyl+cypermethrin and deltamethrin demonstrate the fastest and the strongest effect on the young larvae of the potato tuber moth > 90% mortality. Indoxacarb and acetamiprid also achieve a high mortality rate of > 90% but the effect is slower. Imidacloprid demonstrates the weakest larvicidal effect during the laboratory testing. In accordance with the effectiveness, which is based on the control over the extent of damages under field conditions, the active substances rank as follows: chlorantraniliprole > indoxacarb > deltamethrin > chlorpyrifosethyl+cypermethrin > acetamiprid > imidacloprid. Chlorantraniliprole and indoxacarb provide the most effective and the longest control on the potato tuber moth but, unfortunately, they have not been registered on tobacco. Of all the active compounds registered to be used on tobacco, deltamethrin and chlorpyrifosethyl+cypermethrin can be successfully applied during the attacks of the potato tuber moth and to exercise mutual control over tobacco pests. Acetamiprid and imidacloprid can be applied together to control tobacco pests and also during the attacks of the potato tuber moth in the initial stages after planting, i.e. as the period of protection of the tobacco plants is extended, the extent of damages increases.

Keywords: chemical control; Phthorimaea operculella (Zeller); tobacco

Date published: 2019-01-28