Study on utilization of trichogramma for controlling some insect pests in Quang Nam province
2000
Pham Van Lam | Tran Thanh Thap
Experiments on release of Trichogramma sp. and Trichogrammatoidea sp. in the controlling some Lepidopterous pests were conducted in Quang Nam province during 1997-1998. Release of Trichogramma sp. were carried out five times with total of one million wasps per ha in the August generation of Chilo sacchariphagus (Bojer). The egg parasitization of Chilo sacchariphagus by Trichogramma in released the parasitism percentage of eggs by 13.3 percent, compared with the untreated plots (natural parasitism by parasitoids on eggs of Chilo sacchariphagus occurred at a high level of 66.7 percent). In the control of Ostrinia furnacalis Guen, we released Trichogramma sp. five times at a rate of 500,000 wasps/ha. The rate of parasitism in released plots increased to a level of 68.2 percent, while the rate of parasitism in untreated plots was only 24.8 percent. As to Cnaphalocrocis medinalis Guen.. we released Trichogrammatoidea sp. two or three times at a rate of 250,000 wasps/ha. The parasitism percentage of eggs of C medinalis was increased by 39.4-47.7 percent, compared with the control plots.
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