Laboratory and field evaluation of Trichogramma embryophagum efficiency in presence of buckwheat, Fagopyrum esculentum

Parasitoids of the genus, Trichogramma are the most widely used natural enemies for biological control of pests worldwide. The presence of flowering plants can improve efficiency of biological control agents by supplying sugar resource for parasitoids. In this study, two experiments were performed under laboratory condition (at 25±1ºC, 60±10% RH and a photoperiod 16L:8D), to evaluate the effect of buckwheat (Fagopyrum esculentum Moench) on biological characteristics of Trichogramma embryophagum (Hartig). The two conducted experiments were: 1) Study of biological characteristics of T. embryophagum in the first 24 hours after adult eclosion on floral plant buckwheat versus honey 10% and control (no feeding). 2) Study of the biological characteristics of T. embryophagum with continuous feeding on some nutritional resource as mentioned above during their adulthood. The angoumois grain moth, Sitotroga cereallela Olivier, eggs were used as a host in all experiments. In both experiments longevity was (3.26±0.22 and, 5.6±0.18 days, respectively) and number of host parasitized (36.8±2.78 and 63.36±1.6 eggs, respectively) of wasps in presence of buckwheat were significantly more than another treatment and control. In subsequent of laboratory experiments, a field survey was performed to evaluate T. embryophagum efficiency in presence of flowering buckwheat as an intercropping system with corn. Twenty sitocards were randomly placed in treatment and control field as an egg trap. The mean number of parasitized Sitotroga eggs in each card by T. embryophagum in the corn field with buckwheat and control field was 19.91±5.58 and 4.33±1.13 eggs, respectively that were significantly different. The results clearly showed the significant effect of flowering buckwheat on the efficiency of T. embryophagum that could be useful to develop an inundative biological control program using Trichogramma.