2022년 10월부터 2023년 5월까지 친환경 딸기재배 농가에서 점박이응애는 칠레이리애응애와 사막이리응애, 진딧물은 콜레마니진디벌을 대상으로 하는 천적처리구와 유기농자재를 사용하는 관행방제구에서 천적의 해 충 밀도억제 효과를 조사하였다. 천적처리구에서 점박이응애 성충 밀도는 잎당 1.5마리 이하, 알은 4개 이하로 관리되었고, 사막이리응애는 잎당 최대 0.4마리까지 증가하여 점박이응애 밀도억제에 많은 영향을 미친것으로 보인다. 반면, 관행방제구에서 점박이응애 밀도는 천적 방사구에 비하여 오히려 많은 발생량을 보였지만, 3월 9일부터는 사막이리응애의 증가와 유기농자재의 효과로 점박이응애 밀도는 급격하게 감소하였다. 진딧물 천적 처리구에서 진딧물 밀도는 1월부터 발생하였으며 3월 상순에 잎당 0.3마리까지 증가하였으나 이후 감소하였고, 콜레마니진디벌은 진딧물 발생이 많지 않아 3.9마리/㎡(2회) 방사하는 데 그쳤다. 한편, 관행방제구 포장의 진딧 물은 유기농자재의 영향으로 거의 발생하지 않았다.

Entomopathogenic fungi formulated as wettable powders and suspension concentrates have been sprayed to crop pests for pest management. However, the use of fungal granules to control paddy field pests has not been fully explored. Herein, several Beauveria bassiana isolates (ERL 1170, 1578 and 836) were produced as granules using a millet-based solid culture. The granules were applied to the rice nursery 3 days before transplanting and their control efficacy against rice water weevils was determined in paddy fields. The solid cultures produced ~1×108conidiag-1ofmilletgrains10daysaftertheinoculation. The granules were applied to the soil in the rice nursery 3 days before the rice seedlings were transplanted in the paddy fields. Rice in plots with granules of ERL1578 had 17.3% leaf damage (74% control efficacy) 14 days post application, whereas rice plants in the non-treated control had 66.5% damage. Rice plants treated in the nursery with ERL1170 and ERL836 had 52~54% damage. In the rice plots previously treated with ERL1578 the smallest numbers of larvae and adults were observed 38 days post application. In laboratory conditions, ERL1578-treated larvae were tuned pink and covered with mycelial mass. Applications of millet-based B. bassiana granules on rice nursery soil can be an effective and efficient biological control strategy for the management of rice water weevils. This method is relatively inexpensive and requires less labor compared to practices involving the spraying of fungi directly on rice in paddy fields.

Mealworms, Tenebrio molitor (L.) is used as an important animal feed additive for growth promotion and health management, but potentially exposes to fungal infection. In this work, virulence of two species of entomopathogenic fungi against the insect, and the relationship between abiotic features and virulence were investigated. Secondly our consideration was also given to the effect of chemical fungicides on conidial germination for risk control. Between Beauveria bassiana (Bb) and Metarhizium roberstii (Mr) (previously M. anisopliae), Bb isolates had much higher virulence (~100% mortality in 3~4 days after the treatment), rather than Mr isolates in laboratory assays. Next, fungus-treated mealworms were kept at wheat bran at 20, 25, 30 and 35℃ with 3, 6, 9 times of water spray to the feeds for set-up of different humidity conditions. Inoculation of fungi to mealworms was conducted by fungal spray and feeding methods, which resulted in higher virulence in feeding method. In the feeding method, all temperature treatments except 35℃ showed high virulence against mealworms, but any significant relationship between virulence and humidity was not observed. In the chemical fungicide screening, fluazinam (CAS No. 79622-59-6) and mancozeb (8018-01-7) significantly inhibited the germination of Bb and Mr conidia. This work suggest that contamination of wheat bran with fungal pathogens, particularly B. bassiana may induce mycosis of mealworms, but introduction of effective fungicides possibly reduce fungal infection.