Research in laboratories around the world have demonstrated that Trichoderma harzianum is an opportunistic plant symbionts. One strain of this fungus is extremely proficient in colonizing plant roots and in controlling diseases. It was developed in this lab and is manufactured and sold on a worldwide basis. However, its mechanisms of action are still not fully known. In cooperation with Jie Chen, Jiao Tong University, and Shiping Tian, Chinese Academy of Sciences, as well as others, we have made substantial progress. Using maize as a model system we have demonstrated that (a) root colonization with T22 increases growth of roots and shoots that leads to a yield increase, (b) that root colonization induces systemic resistance to plant diseases on the leaves, and (c) that seed treatments with T22 increase nitrogen use efficiency. However, there are significant genetic differences with maize to T22 and its ability to induce these responses; each may be independently inherited. The maize response resulting in increased growth appears to be a single gene dominant trait. We are measuring pathogenesis related enzyme activity as a measure of resistance induction. Further, a major effort to understand the response of Mo17, a strongly positive inbred, is being conducted using proteomic approaches.
展开▼
