Proteins Specific To Floral Organs At Low Temperature Stress At Booting Stage In Rice In Cold Region

Rice is the major grain which feed more than60%of the world’s population. However, the cold damage on rice cultivation is the common problem. The floral organ is the most closely related to rice production, and its normal development is the key to high yields of rice. The floral organ is the most sensitive and most easily damaged organ to low temperature at the booting stage. But there is few studies on flower organ. The reason is the character of rice floral organs is relatively small, the same as other monocot plant, which is very difficult to study and much harder to gain, comparing with the rice seedlings.So the current cold tolerance on rice research always focuses on rice seedlings, mainly using the leaves and roots. In this study, with the help of artificial climate chamber, we tried to study at the booting stage of rice in cold regions as materials Kong Yu131to varieties of Long Jing11, reference to the stage of booting at room temperature (25℃) and chilling stress (15℃) compared test. The results showed that:1Chilling Stress at booting stage may lead to low rice seed rate. Different kinds of rice have different reactions to low temperature. The decrease of seed rate may be of great difference. Facing the same low temperature at the booting stage, the Rice Kong Yu131was of greater resistance, while Rice Long Jing11was more sensitive.2In this study, the grinding time in the booting stage of rice floral organ extraction operation and the centrifugation step before isoelectric focusing were optimized. We believed that the step of grinding for30min could obtain a higher yield of protein. We thought before isoelectric focusing, if we add using the step of4℃,28000g,45min’s centrifugation to the sample may obtain the2-DE map of less horizontal and less vertical stripes. After low-temperature treatment at booting stage, the seed rate of Long Jing11drops from78.11%to6.63%, while the seed rate of Kong Yu131decreased from93.4%to74.3%, which is much smaller than the control variety of Long Jing11. The control variety of Long Jing11shows much more sensitivity to the chilling stress at such stage.3Compared to Control Condition(25℃),Chilling Stress(15℃) had effect on the young pancils of both Rice Long Jing11and Kong Yu131.There were14protein spots up-expressed in Long Jing11,in which4protein spots only appeared under Chilling Stress.308protein spots were down-expressed in which239only appeared in Control Condition.While under Chilling Stress,57protein spots were up-expressed,59protein spots were down-expressed, however, there was no new protein spots appeared in Kong Yu131. Under stress, plants will be induced to a number of new proteins or protein content of the original will be significantly increased to meet the stress responses. It can be speculated that this was the important reason why differential protein spots appeared Rice Kong Yu131rice panicles after low temperature of15℃treatment.4After using PdQuest Advanced8.0.1two-dimensional electrophoresis gel analysis software, we got such knowledge that there are27protein spots which is especially expressed the Rice Kong Yu131’s floral organ against the Chilling Stress at booting stage. Among these protein spots,11proteins showed significantly in differently expressed ways between Rice Kong Yu131and Long Jing11while16protein spots had the same expressed ways between the two. Located in pI4-6, these proteins would be used for mass spectrometry further identification.