小麦突变体返白系生长后期某些生理变化

返白过程之后，返白系随着叶色的复绿，植株的代谢机能开始恢复，叶绿素含量上升，光合作用增强，叶片内可溶性糖含量上升，呼吸速率高于其祖先矮变１号；复绿初期返白系气孔阻力高于矮交１号，蒸腾速率则低于矮变１号。复绿后，以上各项指标都逐渐变化，达到矮变１号的水平。之后，返白系的蒸腾速率高于矮变１号，气孔阻力低于矮变１号，叶绿素含量及光合速率均高于矮变１号，近白系和矮变互号的呼吸速率在５月９～２５日间有上升趋势，但近白系呼吸速率较高。在生长后期，返白系的根系有向土壤深层分布的趋势。分析认为返白系在生长后期有一个补偿性生长阶段，通过改善植株水分状况，提高同化能力，降低消耗来保证生长和结实的需要。

Some Physiological Changes of the Mutant Line with Early Albinism in the Late Growth Period

This study dealt with some physiological changesin the mutant line of winter wheat with early albinism in the late growth period, compared with the original variety " Aibian No. 1". The results show that, after the process ofalbinism, with the regreening of the leaves of the mutunt type, the metabolism of the mutunt plants began to recover. It was reflected in that thecontent of chlorophylls increased, net photosynthesis was enhanced, the content of leaf soluble sugar gradually increased, and the leaf (dark ) respiration was higher than the original variety. At the beginning of the regreening process, the stomatal resistance of the mutant plsnts was higher than the wild plants, but the transpiration was lower. After the leaves of the mutant plants regreened entirely, the above physinlogical indices of the mutant type changed gradually, and approach those in the original variety. Afterwards,the transpirate, net photosynthesis and content of chlorophyll were higher than those of the original variety. The leaf (dark) respiration at the late stage (on25, May) increased and higher than that of the original variety, the stomatal resistance was lower. The rootsystem of the mutant plants was distributed more deeply in soil than the original variety. Basing on these results it is suggested that there is a compensatory effect in the physiological andbiochemical changes of the mutant plants during the late growth period.Better water status enhanced photosynthesis, the higher carbon assimilation and lower dissimilation ensure that the requirement of growth and productionof grains be wet.