| 摘要: | 大量使用農藥造成環境污染，為減少農藥使用，永續性生態農業勢必取代傳統農業。植物除具有植物相剋作用之特性外，亦含抗病原菌及昆蟲之天然物，相對於高毒性之人工合成藥劑，使用易分解之生物農藥則可減少環境污染。緣此，擬利用植物相剋作用及抑制植物病原菌的理論以發展生物農藥。農林作物種類繁多，舉凡銀合歡、鳳凰木、相思樹、血桐等。若能利用作物殘體做為生物防治劑，不但可提高農林廢棄物之利用價值，更可進一步推動生物防治產業。在先前的研究中將荔枝及黑板樹殘體進行雜草或作物之種子發芽、根生長、抗病原菌及昆蟲之生物分析、溫室土壤盆栽實驗顯示對雜草種子發芽生長及抗病原菌具有良好的抑制效果，極具潛力發展為生物農藥，本計畫將針對這兩種植物分離其中有效成分。本計畫擬將數十種農林殘體乾燥磨粉後，進行雞尾酒式配方加以組合，將最佳比例之殘體進行田間試驗，並建立先導工廠，將此殘體製成顆粒劑，在本校育成中心輔導下將產品技術化，尋求廠商進行產學合作。 Dihydroferulic acid (DFA)之衍生物具有很強之抗菌與抗黴菌作用，此化合物經微生物作用後成為vanillic acid為相剋物質。本計畫擬將部分官能基進行官能基轉換，並與非蛋白質胺基酸進行耦合反應以評估其對種子發芽、根生長、抗菌、抗黴菌作用。也將對其餘常見的酚酸類相剋物質進行結構修飾以特定基因剔除之酵母菌為篩選平臺，並嘗試與抗黴菌藥合用以及評估是否可以降低劑量與解決抗藥性的問題。
Developing the bio-agrochemicals to replace the traditional agrochemical becomes an important issue, because the use of synthetic agrochemicals has caused serious environment pollution due to their poor biodegradability. Allelochemicals are metabolites released from plants that might be beneficial or detrimental to the growth of plants, fungi, insects and microorganisms. The chemicals are often produced during the decomposition of agriculture and forest debris in soil. Furthermore, these compounds can be used as natural bio-agrochemicals, such as herbicides, fungicide, nematoticides, insecticide, etc. Chou and his associates studied the allelopathic potential of several dominant vegetations, namely Leucaena leucocephala, Delonix regia, Acacia confusa and Macaranga tanarius which exhibited strong allelopathic properties and many natural allelochemicals were found. Previous study showed that the leaves and twigs of Nephelium litchi and Alstonia scholaris exhibited excellent inhibitory effects on the weed germination and growth and against tree pathogen fungi by bioassays and pot experiment suggesting the debris from those two plants have potential to become bio-agrochemical. Therefore, phytochemical studies will be continued to investigate the active constituents and allelochemicals. We are going to collect and integrate ground plant debris and fallen litter, such as L. leucocephala, A. confusa, M. tanarius, Eucalyptus maculata Hook. var. citriodora, D. regia, N. litchi, Nerium oleander, A. scholaris, Mangifera indica and Syzygium samarangense, to develop bio-agrochemicals according to the results from the field test. Subsequently, a pilot plant will be established in order to commercialize the formulae by the assistance of the Biotechnology Incubation Center, China Medical University. Dihydroferulic acid (DFA) has been reported to undergo microbial degradation to vanillic acid which is known to be an exuded allelochemical. Some of its corresponding esters showed strong antibacterial and antifungal activities. We will embark on performing functional group transformation to this compound and/or other allelochemicals and coupling with nonprotein amino acids in order to control the growth of Aspergillus flavus using Saccharomyces cerevisiae in a model target-gene bioassay. The activity of some commercial fungicides will be assessed by co-application with those derivatives to lower the dosage and to resolve the problem of resistance. The lead compound will be added to the optimized formula to evaluate its activity and potential as being bio-agrochemicals. |
