| To study on the cold-resistance of leaf-colored plants, the characteristics of physiology and bionomy of dormant detached-buds, detached-branches and booming flowers were determined in this paper. With various treatments of low temperatures,the major results were summarized as follows:1.In this experiment,the relative conductions of all organs become more and more bigger as the decreasing of the temperature.There is an acute increase temperature, which is -10℃(dormant-buds) ,-20～35℃(dormant-branches), -3～-5℃(petal) ,-3℃(stamens), -1℃(pistils).2.The lethal temperature50(LT50) of four species of leaf-colored plants, dormant-buds were -10.02℃, -11.48℃, -10.96℃, -10.65℃. dormant-branches were -20.17℃, -37.76℃, -36.80℃,-30.55℃. petals were -3.09℃, -3.63℃, -3.23℃, -4.45℃. stamens were -1.01℃, -2.94℃, -1.20℃, -2.94℃. pistils were -1.05℃, -2.83℃, -1.05℃, -2.92℃.3.The SOD activities trend were different. SOD activities of dormant-branches and flower floral organs were increased in the first stage, dropped after the critical temperature reached, the critical temperature of dormant-branches were -15C, petals were -3～-5℃, stamens were -3℃, pistils were -1℃. The dormant-buds SOD activities reached the first peak at -10℃, and raised from -20℃,reached the second peak at -35℃.The dormant-buds SOD activities were higher than branches, petal were higher than stamen, pistil under the same treatment.The dormant-buds POD activities dropped in the stage. The changes trend of dormant-branches of Prunus cerasifera var atropurea, Prunus cerasifera var atropurpurea and Prunus×bliriana'Meiren' were raised in the first stage, and then dropped. The activities of POD of flower floral organs were increased in the first stage, and then dropped after the critical temperature reached,the critical temperature of petal were -5℃,stamen and pistil were -3℃.The activities of POD of Prunus cerasifera var atropurpurea were higher than the other species under the same treatment.4.The contents of MDA of dormant-buds reduced in the first stage, but increased on the -30℃, and then reduced again with the temperature dropping.There were two peaks in the line of the the contents of MDA of dormant-branches, rising in the period of CK～-10℃and -15～-30℃. The contents of MDA of stamen and pistil increased in the first stage,and then dropped after the critical subzero temperature reached.The contents of MDA of Prunus cerasifera vat atropurea were highest, and Prunus cerasifera var atropurpurea were lowest under the same treatment.5.The curve of the soluble protein content of dormant branches and buds had two peaks, the peaks were at -15℃and -30℃, the relative amplitude of the soluble protein from strong to weak were Prunus cerasifera var. atropurpurea, Prunus×cistenena 'Purpleleaf and Chevry',Prunus×bliriana'Meiren', Prunus cerasifera var. atropurea.The content of the soluble protein of petal rising in the period of CK～-5℃, and stamen and pistil rising in the period of CK～-3℃. The content of the soluble protein of Prunus cerasifera var atropurpurea were higher than the other species under the same treatment.The contents of soluble sugar of dormant branches and buds were rising in the first stage, and then reduced following with the temperature dropping, when it reached a critical subzero temperature(-30℃).The critical subzero temperature petal were -5℃, and stamen, pistil were -3℃.Before -20℃, the variation of the contents of proline of dormant organs were not regular, before -5℃, the contents of proline of flower floral organs were not regular, but decreased regularly with the temperature dropping.6.The correlation analysis showed, correlation between dormant-branches and dormant-buds was well. The coefficient of correlation was 0.950, reached to obvious significance(P＜0.01). The correlation of flower floral organs was well, the correlation of coefficient of petal and stamen, pistil was 0.836,0.847, reached to obvious significance(P＜0.05). correlation coefficient of stamen and pistil was 0.993, reached to obvious signiflcance(P＜0.01). Dormant organs and flower floral organs.With the index cold-resistance physiology of dormant branches and buds the cold-resistance abilities of 4 species from strong to weak were Prunus cerasifera var atropurpurea, Prunus×cistenena'Purpleleaf and Chevry',Prunus×bliriana'Meiren', Prunus cerasifera var atropurea.With the index cold-resistance physiology of flower floral organs the cold-resistance abilities were Prunus×bliriana'Meiren', Prunus cerasifera var atropurpurea, Prunus×cistenena 'Purpleleaf and Chevry',Prunus cerasifera var atropurea.The conclution revealed that the cold-resistance abilities from strong to weak were dormant-branches, dormant-buds, petal, stamen, pistil. |
