NaCl胁迫下玉米种子萌发过程中超弱光子辐射的变化

Changes of ultraweak photon emission of corn during germination under NaCl stress

为了揭示盐胁迫下萌发种子超弱光子辐射的生物学意义,研究了NaCl胁迫下萌发玉米种子超弱光子辐射的变化规律。结果表明,在对照组的玉米种子萌发过程中,种子鲜质量和自发光子辐射逐渐增长,种子鲜质量和自发光子辐射的变化呈现正相关(相关系数r为0.9614);在50、100和150mmol/L的NaCl胁迫下萌发的玉米种子鲜质量与自发光子辐射也呈现正相关(相关系数r分别为0.9582、0.9406和0.9389),NaCl胁迫对萌发过程中种子鲜质量和自发光子辐射的增长都有抑制作用,NaCl浓度越大,抑制作用越强。研究还发现,NaCl胁迫会导致萌发过程中玉米种子延迟光子辐射中的初始光子数、相干时间和积分强度变小,并且呈现出强度效应。研究结果为揭示盐胁迫下萌发种子超弱光子辐射的生物学意义,开发基于作物耐盐性评价和种质资源鉴定等方面的活体无损检测新技术提供参考。

Biological ultraweak photon emission is divided into spontaneous photon emission and delayed photon emission. It is very important life information from living cells. The study of the ultraweak photon emission about germinating crop seeds is possible to provide a new method of sensitive, fast and nondestructive evaluation of the cell metabolism and functional status. The analysis technology of biological ultraweak photon emission plays an important role in many aspects such as the germination mechanism of seeds, the evaluation of salt tolerance and the identification of crop germplasm. In order to reveal the biological significance of the ultraweak photon emission from germinating corn seeds under salt stress, some corn seeds were placed in different concentrations of NaCl solution, and the changes of ultraweak photon emission in germinating corn seeds under the NaCl stress of different concentrations were studied in this paper. The results showed that the seed fresh quality and spontaneous photon emission from germinating corns in control group were gradually growing in the process of corn seed germination, and there was a positive correlation between the changes of seed quality fresh and spontaneous photon emission （correlation coefficient was 0.9614）; the changes of spontaneous photon emission and fresh quality of germinating corn seed also showed a positive correlation under the NaCl stress of 50, 100 and 150 mmol/L （correlation coefficients were 0.9582, 0.9406 and 0.9389 respectively）. The study also showed that NaCl stress inhibited the growth of the seed fresh quality and the increase of spontaneous photon emission in corn seeds during germination, and the higher the concentration of NaCl, the stronger the inhibition. The change of the spontaneous photon emission provides the information about the decrease of respiration metabolism and DNA synthesis in germinating corn under the stress of NaCl according to the biological significance of spontaneous photon emission. The study also showed that the delayed photon emission of germinating corn excited by blue LED had changed under NaCl stress, and in the control group, the kinetic parameters such as initial photon number and coherence time about delayed photon emission of germinating corn gradually increased with the germination time, and the integral strengthof delayed photon emission of corn seeds increased rapidly in 2 days after absorption, then held steady. It was also found that NaCl stress inhibited the increase of the initial photon number and coherence time about delayed photon emission of germinating corn, and caused the integral strengthof delayed photon emission from germinating corn seeds to decrease, the greater the concentration of NaCl, the smaller the integral strengthof delayed photon emission. The changes of the kinetic parameters of delayed photon emission about germinating corn seeds showed that NaCl stress could cause reactive molecules in seeds cells to reduce, organization and metabolic order to become disordered, and cell function to decrease. These research results provide a reference for explaining the response mechanism about the germination of corn under salt stress.