Study On Rhizosphere Moisture And Phosphorus Environment Change Of Rice Root Response

Root is a primary portal by which a plant absorbs nutrients and moisture from the soil. Different fertilization ways will affect the plant root architecture that will affect nutrients acquisition efficiency of plants. Water regulation (alternate drying and wetting) can make roots adaptive changes (deeper roots), thus to achieve the results of water saving and yield stabilizing. The adaptive changes of crop roots are beneficial to uptake and utilization of soil P. And the adaptive growth phenomenon of roots may be induced by 14-3-3 proteins which are regulatory factors in plants. There are differences in Zhonghan 3 (Upland rice) and Nipponbare (Paddy rice) when response to low phosphorus and dry-wet alternate treatments. And the differences between Zhonghan 3 and Nipponbare at ionomical and molecular biological level were researched. The main results were as follows:1. The relevant data about the root morphology of Zhonghan 3 and Nipponbare with low phosphorus and dry-wet alternate treatments, such as total root length, main root length, total dry weight and phosphorus uptake, showed that compared with Nipponbare, Zhonghan 3 is better in root growth, and has higher phosphorus removal efficiency.2. Through the rhizosphere chromogenesis in situ and rhizosphere noninvasive micro measurement technology, the results of rhizosphere proton secretion with low phosphorus and dry-wet alternate treatments, showed that the proton secretion of roots of Zhonghan 3 was higher, and increased with the increase of time, while the rhizosphere proton secretion of Nipponbare decreased as the extension of time.3. The RNA expression profiles of 14-3-3 proteins of rice roots with low phosphorus and dry-wet alternate treatments showed GF14b, GF14c were involved in the signaling pathways to the stress, and possibly played a very important role in low phosphorus and drought signaling pathway.4. With the soil column experiment system, the low phosphorus and dry-wet alternant treatments were also carried, the results showed that compared to normal treatments, there is no significant change in rice grain weight, grain length and grain width with low phosphorus and dry-wet alternate (low phosphorus and low water) treatments, which means the low phosphorus and dry-wet alternate treatments also reach the water saving, phosphorus saving and yield stabilizing.To sum up, by low phosphorus and dry-wet alternate treatments, the root growth, the phosphorus efficiency, the ionic changes of root surface, the gene expression of the 14-3-3 proteins and the agronomic traits (grain weight, grain length and grain width) of rice of Zhonghan 3 (Upland rice) and Nipponbare (Paddy rice) was studied. The results showed that the 14-3-3 proteins might play an important role in the regulation of rice roots response to the rhizosphere moisture and the rhizosphere phosphorus environment.