| Tomato grey mould is one of the important crop diseases around the world. It seriously damage to more than 20 kinds of crops, such as tomato, eggplant and so on. It causes crop yields decreased by 40%-50%, and even results in fully lose of tomato production. Chemical pesticides are most currently used for the control of tomato grey mould. However, chemical pesticides not only seriously affected the human health, but also caused severe environmental pollution. Therefore, Traditional Chinese Medicine (TCM) fungicide, as a new type of botanical pesticides, become a promising possible alternative to chemical pesticides for the control of crop diseases.China is one of the rich countries in natural medicine resources over the world. Sichuan, the province which is famous as "the hometown of TCM", has more than 4000 species of TCM, accounts for about 34% in the whole country. Sichuan authentic herbal medicines with antifungal and antibacterial activities have the unique resources advantage. Therefore, in order to promote the research and development of TCM fungicide and to control of the tomato grey mould.20 species of Sichuan authentic herbal medicine were used to in the present study. The results obtained are as follows:1. The active extracts from 20 species of Sichuan authentic herbal medicine were obtained using 6 kinds of solvents, including ethanol, ethyl acetate, acetone, chloroform, petroleum ether and water. The inhibitory effects of these extracts on B. cinerea were examined by mycelial growth rate method. The results showed that when the concentration was 0.1g/mL, the inhibitory rates of 7 kinds of alcoholic extracts including Acorus tatarinowii, Phellodendron chinense, Iris tectorum, Zanthoxylum bungeanum, Coptis chinensis, Rheum palmatum and Aconitum carmichaelii,6 kinds of ethyl acetate extracts including A. tatarinowii, I. tectorum, C. chinensis, Platycodon grandiflorum, Quisqualis indica and A. carmichaelii,2 kinds of trichloromethane extracts including Dipsacus asper and Lonicera japonicae, and the acetone extracts of A. tatarinowii were 100%. Further comparative study found that the inhibitory effect of A. tatarinowii ethanol extract was the best among 120 kinds of extracts.2. The single factor test and orthogonal array design were used for selecting the optimal extraction process. The results showed that the best optimal extraction conditions were as follows:temperature was 38℃, time was 12h, volume fraction of ethanol was 100%, olid-to-liquid ratio was 1:12, rotating speed was 240r/min. The influence degree of factors was temperature> rotating speed> time>volume fraction of ethanol> solid-liquid ratio. The optimum extraction times was 3, extraction ratio was 2.65%, and about 92.5% of the effective components was extracted.3. The antifungal stability of A. tatarinowii ethanol extracts on B. cinerea was tested by mycelial growth rate method. The results showed that its antifungal activity was not influenced by pH or UV-irradiation, the antifungal activity decreased when the temperature was higher than 78℃, and increased when the concentration of saccharose in culture was higher than 0.08 g/mL, it was stable when stored at 22～28℃ or 4℃.4. The effective antifungal concentration was be determined by solid culture medium dilution method. The results showed that the extract not only can inhibit the growth of B. cinerea, but also can inhibit the growth of Phytophthora infestans and Curvularia lunata. The MIC were 0.04 g/mL,0.03 g/mL,0.05 g/mL, respectively. The MBC were 0.06 g/mL, 0.06 g/mL,0.08 g/mL, respectively.5. The inhibition rate of conidial germination were tested by microscope concave slides method, the control effect of the extract on tomato grey mould were determined by pot-culture method. The results showed that its EC50 and EC90 on spore germination were 0.0109 g/mL and 0.0318 g/mL, respectively. its EC50 and EC90 in control were 0.0221 g/mL and 0.1533 g/mL. respectively. So the spore germination and tomato grey mould can be effectively inhibited by ethanol extract from A.tatarinowii.6. Determined germination rate, germination potential, germination index, emergence time, emergence rate, and seedlings height after treatments. The results showed that the germination activity and the emergence rate of seeds was no difference compared with CK when the concentration was 0.005～0.02g/mL, and it was inhibited when the concentration was 0.04-0.32g/mL. The emergence of seeds was enhanced and the seedlings height was no difference compared with CK when the concentration was 0.005-0.08g/mL, and they were inhibited when the concentration was 0.16-0.32g/mL.7. The activity of PAL, PPO and POD was determined by colorimetry. The results showed that the activity of PAL. PPO and POD was improved when the concentration was 0.04～0.16g/mL, and they were inhibited when the concentration was 0.64g/mL.In conclusion, A. tatarinowii, P. chinense, I. tectorum, Z. bungeanum, C. chinensis, R. palmatum, A. carmichaelii, P,grandiflorum, Q. indica, D. Asper and L. japonicae can be used to develop TCM fungicide for controlling of B. cinerea. The ethanol extract from A. tatarinowii was the best material among 120 kinds of extracts could be used for the further development of TCM fungicide. The extraction technology was convenient, extraction efficiency was reasonable, stability was high, the wide antifungal property were good, the inhibitory activity on mycelial growth and spore germination of B. cinerea was great, the control effects on tomato grey mould was efficient, the extract with low concentration had little effect on germination and emergence rate of tomato seeds, and it can shorten emergence time, promote seedling growth, and enhance the activity of defensive enzymes. |
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