The Key Techniques For Regulation Of Flowering Time Of Browsing Sunflower During National Day In Shanghai

Sunflower,native to North America,is an annual herb of the genus Helianthus in the composite family.In this study,32 kinds of ornamental sunflower varieties were used as experimental materials to investigate the phenophase,morphological characteristics,main characteristics and applications.Besides,the effects of different temperature on germination rate and germination potential of sunflower were studied.Moreover,we investigated effects of shading treatment and pinching on sunflower florescence and its landscape application.The results are as follows:(1)Effects of different media and temperature on seed germination of ornamental sunflowerThe germination rate and germination vigor of ornamental sunflower seeds on coconut coir were higher than those on paper.The germination rate and germination vigor of ornamental sunflower seeds were lowest at 15 ?C.And the germination rate and germination vigor increased significantly when the germination temperature rose to 20 ?C.When the temperature was 25 ?C and 30 ?C,the germination rate and germination vigor had no significant change compared with the temperature of 20 ?C.When the temperature was increased to 35 ?C,the germination rate and germination vigor decreased significantly when compared to 20 ?C.(2)Screening of high temperature resistant varieties‘Kai xin xiao ai ren'?‘Hao yun duo'?‘Chu shui fu rong'?‘Feng shou le'?‘Mou nai' and ‘Lv tian shi' are the six ornamental sunflower varieties.These seeds of above six varieties in the coconut coir which have higher germination rate and germination vigor can be used as high temperature resistant varieties.(3)Effects of shading and pinching on sunflower florescenceThe florescence of ornamental sunflower varieties,e.g.'golden 08','Huang zuan','Hao yun duo','Huo li','Bao shi hong fang' and 'Zui yun chang',could be prolonged by 50% and 75% shading treatment.And the effect of prolonging the flowering time is mainly by slowing down the fading of flowers.Pinching could also prolong the flowering time of 'Huo li','Bao shi hong fang' and 'Zui yun chang'.(4)Landscape application of ornamental sunflowerOrnamental sunflower is often used as cut flowers,potted plants and landscape configurations and application,but has different requirements for varieties 'Huo li','Pa ti xiao kui' and other varieties with more inflorescence can be used as sunflower fresh cut flowers.'Hao yun duo' and other dwarfing varieties with more inflorescence can be used as pot culture.Tall,dense and lodging resistant varieties 'Mei gui qing' can be used as plant wall and a plant maze.