Relationship Between Leaf Age And Leaf Color Of Salix Chaenomelodies 'Variegata' And The Effect Of Light Quality On Coloration

The color-leafed plant is widely used in landscaping,because of its graceful,colorful and seasonal changes.Salix chaenomelodies ?Variegata? is a common color leaf plant of the genus Salix chaenomeloides.The upper leaves of the twigs are bright red at the growth stage.As the leaf age increases,the leaves gradually turn yellow and eventually turn green.Throughout the growth period,the Crown has three kinds of colors,with excellent ornamental value.At present,the study of.Salix chaenomelodies ?variegata? is focused on breeding,domestication and domestication.The study on leaf coloration is still rare.Therefore,in order to explore the correlation between leaf age and leaf color,the effect of light quality on Salix chaenomelodies coloration was summarized and the following studies were made: by observing the color of different leaf age Salix chaenomelodies leaves,determining leaf color parameters,pigment content,phenylalanine solution Ammonia enzyme activity and soluble sugar content;At the same time,treated the Salix chaenomelodies ?Variegata? in the vegetative period and dormancy induction period.with red,yellow,blue,green,and white light qualities.The above indicators,red leaf count,and net photosynthetic rate were also determined.The following conclusions were obtained:1.The color of the leaves of the growing Salix chaenomelodies ?Variegata? in vegetative period shows a phase change.From top to bottom,it can be divided into three stages: red,yellow,and green.Within 18 days after germination,the leaves showed a steady bright red color;with the increase of leaf age,the red leaves gradually turned brown.On the 27 th day or so,the leaves turned completely yellow;the yellow leaves continued to mature and turned to yellowish green until On the 39 th day,the leaves turned green completely.2.The leaf coloration of the Salix chaenomelodies ?Variegata? is mainly determined by the contents of chlorophyll,carotenoid and anthocyanin.The higher level of anthocyanin content was the main reason for the fresh red color of the new leaves.On the 18 th to 27 th day after the leaves germinated,the anthocyanins degraded rapidly,the chlorophyll and carotenoids increased slowly,and the red color regressed.About a day,it turns yellow;with the continued growth of the leaves,anthocyanin content stabilizes,chlorophyll and carotenoid content increase rapidly,and chlorophyll becomes the dominant pigment of leaf color.On the 39 th day,the leaf color completely turns green.Phenylalanine ammonia lyase is an important factor regulating the content of anthocyanin in leaves,and its activity is significantly positively correlated with the content of anthocyanins.Soluble sugar is not a factor that affects the content of anthocyanin in the leaves of Salix chaenomelodies ?Variegata?.3.The Salix chaenomelodies ?Variegata? cultivated in the open field had the strongest photosynthesis under the yellow light treatment,but the blue light and the green light were not easily absorbed.However,in the process of light treatment,Salix chaenomelodies ?Variegata? can adapt to several light qualities quickly,and the net photosynthetic rate can return to normal.After the blue,green and yellow light treatments are completed,the photosynthesis under natural light is significantly higher than that of other light qualities.However,green light has a sustained inhibitory effect on photosynthesis of Salix chaenomelodies ?Variegata? in the dormancy induction period.4.Red light is best for red leaves,and blue and green light causes red leaves to turn green;PAL activity was regulated by light and was significantly correlated with pigment content.Under red light treatment,under red light treatment,the number of red leaves increased,leaf anthocyanin content increased,especially in the dormancy induction period,can inhibit anthocyanin degradation,and delay the synthesis of chlorophyll and carotenoids,extend the time of top leaves turn green,and red watch for longer periods.Blue and green light in two growth stage,all can reduce the number of red leaves,deal with the late only 2 piece,the top blade a* lower and middle leaves red saturation,flower pigment significantly reduced,increased content of chlorophyll and carotenoid.In the process of light treatment,photoplasm can regulate the activity of PAL hydrolyzyme in leaves,thus affecting anthocyanin content.The soluble sugar content was not related to anthocyanin content,so the leaves of the red leaves were not affected by the soluble sugar content.The research results provide a theoretical basis for the rational cultivation and application of the Salix chaenomelodies ?Variegata?.It provides a certain theoretical and practical basis for the exploration of artificially regulated leaf color technology for colorful plants.