This study was conducted to evaluate the efficacy of mulberry leaf mixed diet on larval growth of Protaetia brevitarsis. As a result of adding mulberry leaves to oak fermented sawdust, the survival rate of P. brevitarsis larvae were higher than those of the control when mass rearing larvae. When fed oak fermented sawdust with 5%, 10% and 20% of mulberry leaves, the cumulative proportion of larvae over 2.5g was 93.1% at 65 days, 95.6% at 55 days, and 93.9% at 55 days after rearing at 25±1℃, respectively. Also, heavy metals were not detected in larvae of P. brevitarsis fed on mulberry leaves.
This study was conducted to evaluate the efficacy of mulberry cake mixed diet on larval growth of Protaetia brevitarsis. As a result of adding mulberry cake to oak fermented sawdust and mulberry fermented sawdust, the survival rate of P. brevitarsis larvae were higher than those of the control when mass rearing larvae. When fed oak fermented sawdust with 3, 5% and 10% of mulberry cake, the cumulative proportion of larvae over 2.5g was 92.9% at 65 days, 90.8% at 55 days, and 96.3% at 45 days after rearing at 25±1℃, respectively. When fed mulberry fermented sawdust with 3%, 5% and 10% of mulberry cake, the cumulative proportion of larvae over 2.5g was 86.2% at 85 days, 90.7% at 75 days, and 91.5% at 75 days after rearing at 25±1℃, respectively.
전라북도는 곤충사육농가의 77%인 121농가가 흰점박이꽃무지를 사육하고 있고 농가수의 증가가 예상됨에 따라, 생산단가를 절감시키면서 효율적인 사육을 위해서는 사육환경을 최적으로 유지하는 것이 매우 중요하다. 따라서 본 연구에서는 뽕나무발효톱밥을 이용하여 유충사육밀도에 따른 유충발육상황을 조사하였다. 최적 사육밀도 설정을 위하여 전라북도 사육농가에서 가장 많이 사용하는 20L 크기의 사육 상자에 각각 100, 125, 150, 175, 200마리 흰점박이꽃무지 유충을 넣고 뽕나무발효톱밥을 2/3정도 채운 후 사육하면서 유충무게변화, 생존율 등을 조사하였다. 부화 후 95일 흰점박이꽃무지 유충 생존율은 평균 81%로 사육밀도별 큰 차이가 없었다. 유충 무게는 100마리/20L 사육 시 2.219g로 가장 높게 나타났으며, 사육밀도가 증가함에 따라 감소하는 경향으로 나타났다. 유충 영양성분 조사결과 단백질 52.8g/100g, 지방 11.8g/100g이었으며, 중금속은 검출되지 않았다.
Melon thrips, Thrips palmi Karny (Thysanoptera: Thripidae) is a worldwide polyphagous pest. The management of this pest have mainly relied on chemical agents. However, the overuse is harmful to the environment and results in insects resistance. Therefore, alternative eco-friendly control methods that have different mode of action, such as biological control, are necessary to overcome the current issue. In this study, we isolated entomopathogenic fungi from Korean soil, and characterized them via morphological and molecular techniques and pathogenicity assay against Tenebrio molitor larvae. The isolated fungi were screened for virulence against T. palmi under laboratory conditions and the results were used to establish a thrips-pathogenic fungal library. The highly virulent isolates were selected and further characterized for optimum culture conditions and application as biopesticide in the field.
A species of Beauveria bassiana is widely used for biological pest management in many countries. Many efforts have been given to figure out the clear fungal mode of action to enhance the insecticidal activity. Homologous recombination (knock-out) or hairpin RNA (knock-down) is popularly used in fungal gene function study, but gene cloning and generation of knock-out or -down mutants takes long time or temporarily knock-downed. Here in this work, we used previously generated egfp-expressing B. bassiana strain (Bb-egfp #3) and integrated dsegfp to the Bb-egfp #3 using a protoplast integration method. This work suggests that protoplast integration with dsRNA possibly generate significantly reduced gene expression in B. bassiana and the reduction is quite stable over generations which provide easy of functional study for fungal mode of action.
This study was conducted to investigate effect of feeding beet pulp on reproductive performance, colostrum composition and microbiological characteristics in sows. A total of 12 sows(Landrace×Yorkshire) were randomly allotted three dietary treatments at gestating 90 days. The diets were prepared by adding 0, 5 and 10% of the beet pulp in basal diets. The pigs fed 5% beet pulp showed higher litter size than the 0 and 10% beet pulp treatments, although there was not significant among the treatments. Similarly, birth and 21days weight in piglet were not different among the treatments. In colostrum fat, protein, lactose, citric acid, solid, ffa, true protein were ranged to reference values, but not difference among the treatments. E.coli of feces was lower(P<0.01) in the 5% beet pulp than the 0 and 10% beet pulp treatments. But no effect was observed on Lactobacilli of feces among dietary treatments. These our results indicate the beet pulp has no significant effect of reproductive performance and colostrum composition in sows. But, 5% level beet pulp is effective for reduction of intestinal pathogenic microorganisms.
In order to develop the D. adamsi breeding technique that is highly likely to be used as an emotional pet insect, the results of the D. adamsi was collected in the large exhibition Jang Tae-san in Daejeon to the indoor breeding began to spawn after 10 days after the training, the egg laying period was 33.6 days, the average number of spawn per female was 27.7, and the period was 11.8 days. D. adamsi larvae bred with food of oak-boiled molted two times, the duration of 1st larvae development was 11.8 days, 2nd larvae 14.5 days, and the third larvae was 29.4, and the larvae were used to build houses using Masato(soil) and in the pupae, and then in April of the following year. D. adamsi has a characteristic to build a house with fallen leaves and spawn one or two eggs in the fallen leaves, and the results of the spawn mat test using fallen leaves, leaf mold and a sawdust, etc., and the number of spawn was high in the Masato was spread about 3 ~ 5cm, and a fallen leaves on a 10 cm or so, and the growth and survival rate of the larvae were also high. Larvae breeding density was 2 ~ 3 ℓ in the container size to raise the object was normal growth, the higher the density mortality was high and the growth was sluggish. Larvae feeding conditions were normally developed in dry fallen leaves and fermented fallen leaves, compared to the sterile fallen leaves, oak sawdust, sterile fallen leaves and oak sawdust was abnormal, the mortality rate was higher than 50%.
Insect-killing fungi have high potential in pest management. A deeper insight into the fungal genes at the whole genome level is necessary to understand the inter-species or intra-species genetic diversity of fungal genes, and to select excellent isolates. In this work, we conducted a whole genome sequencing of Beauveria bassiana (Bb) JEF-007 and characterized pathogenesis-related features and compared with other isolates including Bb ARSEF2860. A large number of Bb JEF-007 genes showed high identity with Bb ARSEF2860, but some genes showed moderate or low identity. The two Bb isolates showed a significant difference in vegetative growth, antibiotic-susceptibility, and virulence against Tenebrio molitor larvae. When highly identical genes between the two Bb isolates were subjected to real-time PCR, their transcription levels were different, particularly in heat shock protein 30 (hsp30) gene which is related to conidial thermotolerance. In several B. bassiana isolates, chitinases and trypsin-like protease genes involved in pathogenesis were highly conserved, but other genes showed noticeable sequence variation within the same species. Given the transcriptional and genetic diversity in B. bassiana, a selection of virulent isolates with industrial advantages is a pre-requisite, and this genetic approach could support the development of excellent biopesticides with intellectual property protection.
The continuous emergence of chemical-mediated residual toxicity and insect resistance have enforced the regulation of synthetic pesticides. Synthetic pesticides with novel mode of actions could be developed to overcome these issues, but as an alternative biopesticides with more efficacious control activity could be developed by the advanced technology. In pest management, entomopathogenic fungi have high potential in reducing pest population to an economic threshold, and some of isolates have been commercialized. However still a novel application strategy needs to be considered for successful industrialization. An insight on fungal genes in whole genome and transcriptome levels is necessary to understand the role of genes in pathogenesis and genetic diversity of fungal genes. Herein, we have identified the genetic differences of entomopathogenic fungi using whole genome sequencing of Beauveria bassiana (Bb) and tried to understand the interaction between fungus and insect using RNA-seq. We have obtained the whole genome sequence of Bb JEF-007 using PacBio sequencing technology and compared the transcriptomes of Bb JEF-007 and bean bug, Riptortus pedestris before and after the fungal infection using Hiseq 2000 system.
Entomopathogenic fungi have been known as promising candidates for biological control of insect pests. Recently, researchers consider the fungal thermotolerance in formulations and field applications. In this study, we investigated the production of thermotolerant Isaria javanica and I.fumosorosea conidia through grain-based solid cultures and exposure to light stress. As results, of the ten grain substrates, Italian millet, rice, perilla seed and sesame, rice, sorghum produced highly thermotolerant conidia in the strains. The two strains were exposed to a light stress and showed enhanced thermal stability compared to control, when exposed to 45°C for 2 hours. This work suggests that heatresistant entomopathogenic fungal conidia can be produced by grainbased solid cultures and exposure to light stress.