AgronomyEN

Our lab is highly interested in the interaction mechanism of biotic or abiotic factor in crop and environment.

(1) The Mechanism of Soil Probiotics Promoted Environmental Stress Tolerance to Crop

Globally, concern for the environmental safety is rising. Many countries aim to reduce chemical pesticides. Therefore, it’s an important strategy to replace chemical pesticides with low-risk biological pesticides for pest control. 

The symbiosis of soil probiotics and plants can not only promote plant nutrient absorption and growth, but also have the effect of helping plants resist environmental stress. Our lab focuses on exploring the benefits of soil probiotic fungus - P.indica on crops and its mechanism. P.indica is a probiotic fungus that can promote the growth and the yield of rice. We study on the mechanism of P.indica improves water stress tolerance in rice through physiological, biochemical and transcript analysis. Now we are exploring the mechanism of P.indica induced insect resistance in rice and its signal transduction pathway.

(2) Regulation of a Phloem-Specific Gene Encoding the Sucrose Transporter 4 Protein in Response to Mechanical Wounding and Insect Herbivores-Induced Damage in Rice Plants

       Plant damage is typically caused by insect attack or mechanical wounding, and the injury site is a high risk area for pathogen infection. Thus, both repairing damage tissue and turning on defense mechanism are important plant responses to arrest or against the further injury caused by herbivore or microorganism. Sugars are important nutrient to provide carbon skeleton and energy for tissue repairing, and it often functions as a signal to trigger defensive gene expressions. However, the regulatory mechanism of wound-induced carbohydrate allocation is still unclear. Sucrose transporter (SUT) is significant carriers in charge of apoplastic phloem loading/unloading of sucrose, and it is a key factor to control long-distance transport of sucrose. Activities of SUTs determine carbon flow in plants. In this research project, the major goal is to study the signal transduction and regulatory mechanism of wound-induced OsSUT4 expression. This study will help us to understand the mechanism of wound-induced carbohydrate allocation in rice plants.

(3) Study on the Effect and the Physiological Mechanism of Environmental Factors on the Root Growth in Rice Seedlings.

       Light is an important environmental signal to regulate plants growth. In our research showed that TCN1 (Oryza sativa L. cv. Taichung Native 1; an indica-type rice variety) displayed a wavy root phenotype under light conditions, but a japonica-type rice didn’t display it. Analysis of longitudinal sections of wavy seminal roots indicated that light-induced root waving was caused by the asymmetric cell growth on both side of vascular cylinder cells in the root tips. The light- induced waving pattern is different from the mechanism of root circuitous growth pattern induced by touch stimulation. Polar auxin transport, ethylene, nitric oxide, and fatty acid oxidation are all involved in the physiological mechanism of light-induced waving root pattern. These physiological mechanisms interact with each other to affect root growth pattern.

(4) Regulatory Mechanism of Sugar Transport in Rice Leaf Sheath at the Reproductive Stage

       Rice leaf sheaths of upper leaves are the temporary sink tissues before heading, and the pre-storage starch would be degraded immediately after heading for providing the carbon source to developing grains. The rate of sucrose transport in leaf sheaths at reproductive stage plays an important role to determine the rice yield and quality. Pre-storage starch in upper leaf sheaths also serves as an alternative carbon buffer in unfavorable environment to compensate for insufficiencies of photosynthesis, and it helps to reduce the negative effect on grain yield caused by environmental stresses. Therefore, improving the source function of leaf sheaths by controlling the carbohydrate remobilization would be a powerful approach to enhancing rice production. Sucrose transporter (SUT) is the key carrier for sucrose loading into phloem for further carbohydrate long-distance transport between different tissues/ organs. In our research, OsSUT genes would be used as marker genes to study the molecular mechanism of sink-source transition in leaf sheaths during the heading period. Furthermore, the effect of temperature stress on OsSUT1 and 4 expressions would be analyzed.