Development and use of compounds for the regulation of lignin synthesis in plants

Abstract

Evaluation and use of glyphosate, salicylic acid and AIP to control lignin synthesis in plants.Lignin is a major compound in plants, affecting the use of biomasses (sugarcane leaves remaining on the soil after the harvest, for example) to feed animals, to support industrial processes, like alcohol production, or to produce energy. In these cases, and to produce paper (using wood from different species), to reduce the production and accumulation of lignin can be very interesting. But in no till areas, the accumulation of lignin in cover crops can be also important to increase the amount of mulch that can be kept on the soil. The mulch is very difficult to accumulate in tropical countries due to the fast decomposition. Probably the decomposition is much faster if the cover crop receives a burndown application of glyphosate. If glyphosate application can be avoided and PAL can be stimulated (for example by applications of salicylic acid), the content of lignin (and other phenolic compounds) can be increased. In opposite, the application of glyphosate and PAL inhibitors (AIP) can reduce lignin synthesis. There are several blockers of PAL that can lead to reductions in the synthesis of phenolic compounds in plants, but AIP is the most effective and specific one. AIP and glyphosate are potential blockers of the lignin synthesis in plants and their effects will be evaluated in this project. The compounds will be applied to the leaves of Arabidopsis thaliana. Some activities related to other projects being carried out also will be developed during the stay in NPURU / Oxford – Mississippi and some examples are: evaluation of gene expression as a consequence of glyphosate application or weed interference; evaluation of the effects of low rates of glyphosate on the expression of the gene associated to phosphate transporter; evaluation of hormetic effects of glyphosate; induction of porphyrin synthesis in plants. (AU)