The biocontrol efficacy of Bacillus amyloliquefaciens FS6 against seedling diseases and gray mold of ginseng, as well as application techniques were evaluated in a series of field trials. FS6 fermentation broth showed a strong antagonistic effect against the ginseng fungal pathogens, and the inhibition rates on mycelial growth and spore germination were 84 to 88% and 71 to 72%, respectively. Field evaluation showed that combination of seed and soil treatments exhibited better protection than that of individual treatment alone. FS6 wettable powder (WP) soil treatment in combination with thiamethoxam plus metalaxyl-M plus fludioxonil for seed coating performed the best, with greater than 83% overall control efficacy for seedling diseases. FS6 had a long-acting effect of greater than 78% control efficacy on ginseng gray mold at 30 days after the last application, almost 2.5- and 2-fold better than that of B. amyloliquefaciens B7900 WP and cyprodinil, respectively. In addition, FS6 reduced the diversity and relative abundance of fungi and affected the fungi and bacterial composition in the rhizosphere soil of ginseng. Therefore, FS6 can be used to effectively control seedling diseases and gray mold in ginseng.

Diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is the dominant insect pest of cruciferous crops around the world, and is resistant to many chemical insecticides. In this study, we measured the chemical composition and bioactivity of Artemisia lavandulaefolia DC (Asteraceae) essential oil on P. xylostella. The essential oil was obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry. A total of 35 constituents were identified. The principal compounds were: eucalyptol (35.60%), (R)-4-methyl-1-(1-methylethyl)-3-cyclohexen-1-ol (16.25%), π-trimethyl-3-cyclohexene-1-methanol (6.83%), 3-methyl-6-(1-methylethyl)-2-cyclohexen-1-one (6.63%), and (1S)-1,7,7-trimethyl-bicyclo[2.2.1] heptan-2-one (4.72%). The LD 50 contact toxicity of the essential oil to immature P. xylostella was estimated at 0.045 μL per larva. Artemisia lavandulaefolia oil exhibited fumigant toxicity against P. xylostella adults with an LC 50 of 0.113 mg per L after 12 h and also provided 80 to 100% repellency at a 1% v/v concentration.

Aims: We aimed to purify an antimicrobial protein from Bacillus amyloliquefaciens FS6 culture supernatant, verify its antimicrobial activity against Fusarium solani and evaluate its biocontrol potential for ginseng root rot. Methods and Results: The antimicrobial protein was purified from FS6 culture supernatant using ammonium sulphate precipitation, anion exchange and gel chromatography. Based on mass spectrometry results, the purified protein was identified as an antimicrobial protein of the LCI family and was designated APC 2. The APC 2 recombinant protein expressed in Escherichia coli (BL21) significantly inhibited F. solani and decreased the infection and spread of F. solani in ginseng root. An overexpressing APC 2 strain FS6-APC 2 was constructed and shown to have enhanced antimicrobial activity compared to the wild-type strain FS6. Conclusions: The APC 2 protein shows strong antimicrobial activity against F. solani, reduces the incidence and severity of ginseng root rot caused by F. solani and exhibits a great biocontrol potential. Significance and Impact of the Study: This study reports the inhibitory activity of APC 2 protein (LCI family) against F. solani and its protective efficacy on ginseng root rot. These findings provide a scientific basis for future research on the biocontrol mechanism, as well as the development and application of FS6. 1996; Haas and D efago 2005; Nicolopoulou-Stamati et al. 2016). Biological control is environmentally friendly and less toxic to humans and animals. The application of biocontrol agents can minimize the progression towards pathogen resistance and represent the future of ginseng disease

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In this paper, Chinese herbal medicines of Ophiopogon japonicus, Houttuynia cordata and Duchesnea indica were planted in the soil containg 0.847 mg/kg Cd, which is close to the grade III of Environmental Quality Standard for Soil in China (GB15618-1995). After growth a certain time, the Cd in the three plants were determined respectively. Then the human health risk of Cd intake via taking the herbal medicines was assessed using the internationally recommended method of health risk assessment, as well as accordance to the Standards of Import and Export of Green Medicinal Plants and Their Preparations (WM2-2001), and the Acceptable Daily Intake (ADI) of World Health Organization (WHO). The results showed that, after growth 90d, the Cd contents in the leaves and roots of O. japonicus and H. cordata, and all parts of D. indica were lower than the safe value of Green Trade Standards of Importing & Exporting Medicinal Plants & Preparations (WM2-2001), while that in stems of H. cordata was higher than the safe value. The human health risk of Cd in the three herbal medicines was in the order of H. cordata＞O. japonicu＞D. indica. Under the asumption of 30g as the average daily intake of the three herbal medicines for an adult, the maximum amount of Cd intake per person via O. japonica, H. cordata, and D. indica were 8.7μg, 10.5μg and 6.2μg respectively, which were lower than the allowable daily Cd intake value of WHO and the limit value recommended by the International Committee for Radiological Protection (ICRP). However, as the stem of H. cordata was slightly polluted after growth 90d in grade III soil, it was not recommended to use it as an edible Chinese herbal medicine.