The beet armyworm, Spodoptera exigua has become highly resistant to almost all of the chemicals available in the Chinese market.
In order to ensure a good yield, the farmers sprayed harsh chemicals every three- ten days. However, since alfafa is an important animal feed, it is impossible for the farmers to spray chemicals. Due to the application of TEKEXI on an alfafa farm in Lankao County, China, the beet armyworm population that had been ravaging the 15,000 ha of alfafa for years was successfully under control. Now, the alfafa growers find confidence to cultivate larger area of alfafa.
Three days after the application of TEKEXI, a large number of beet armyworm L1-L3 started to die after being infected with(SeMNPV).The beet armyworm larvae infected with SeMNPV showed several classic symptoms. The larvae gradually stopped feeding and became less active. In the advanced stages of the infection, as the epidermis was infected, the skin of the larvae became very fragile and ruptured easily. The larvae became swollen and the body contents became a fluidized mass of decomposed tissues and viral polyhedra. Just prior to death, the infected larvae climbed to the highest parts of the plants they were located, such as the tops of plants and attached themselves by their prolegs. On death, they hung in a characteristic V-shape.
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