The Research On Cold Resistance And Cutting Propagation Of 16 Bougainvillea Varieties In Changsha City

Bougainvillea is native to South America and is a kind of garden plant with high garden application value,but it has been introduced into China for more than a hundred years.It has only been widely used in warm climate areas in the south of China,such as Yunnan province,Guangxi province,Guangdong province and Fujian province.Recent domestic studies have shown that the Bougainvillea can adapt to the climate and environment of Changsha,so popularizing the garden application of the Bougainvillea can enrich the urban garden tree species and form a richer landscape effect.it plays an important role in promoting the process of "beautiful China" and"rural revitalization".The plant materials in this study were introduced from Hunan Botanical Garden from Kunming,Yunnan Province.In this paper,the phenological phase,growth characteristics,cold resistance,cutting propagation techniques and garden application of 16 Bougainvillea varieties were studied and discussed;and the physiological characteristics of Bougainvillea growth were understood,and the Bougainvillea varieties most suitable for Changsha were selected.Explore the Bougainvillea cutting technology to provide technical support for popularization.Taking Xiamen,Shenzhen,kunming and other cities as the main research sites,this paper investigates the application mode of Bougainvillea in urban green space in Xiamen city,and discusses the garden application of Bougainvillea in Changsha city according to the growth demand of Bougainvillea in Changsha city.The study on the growth rhythm of Bougainvillea shows that most of the 16 Bougainvillea varieties bloom from July to September,the flowering period varies from 6 to 9 months,and the growth peak of most Bougainvillea varieties is from May to June.The order of plant height growth of 16 Bougainvillea varieties from high to low is as follows:’Partha’>’Chitra’>’Mary Helen’>’La Jolla’>’Aussie Gold’>’Lafilte’>’Zinia Barat’>’Cherry Blossom’>’Makeris’>’Golden Glow’>’Singapore White’>’Gold Rush’>’San Diego Red’>’Royal Bengal Red’>’Elizabeth Angus Varegata’>’Bilas’.The order of ground diameter growth from high to low is ’Zinia Barat’>’Golden Glow’>Mary Helen’>’Makeris’>’Aussie Gold’>’Bilas’>’Chitra’>’Gold Rush’>’La Jolla’>’Partha’>’Cherry Blossom’>’Royal Bengal Red’>’San Diego Red’>’Singapore White’>’Elizabeth Angus Varegata’>’Lafilte’.The annual average plant height of Bougainvillea increased by 32.28 cm,the average plant height was 61.42 cm,and the average basal diameter was 13.64 mm.There was no significant correlation between basal diameter and plant height.In the study of cold resistance of Bougainvillea.The results of low temperature,adaptability test of 16 Bougainvillea varieties showed that the cold resistance of 16 varieties was in the following order:’Mary Helen’>’Chitra’>’Zinia Barat’>’Lafilte’>’La Jolla’>’Aussie Gold’>’Partha’>’Golden Glow’>’Elizabeth Angus Varegata’>’Singapore White’>’Royal Bengal Red’>’San Diego Red’>’Bilas’>’Makeris’>’Gold Rush’>’Cherry Blossom’.Further low temperature stress test showed that the order of comprehensive cold resistance from high to low was ’Lafilte’>’Zinia Barat’>’Chitra’>’Mary Helen’>’Aussie Gold’>’Makeris’>’La Jolla’.However,because the semi-lethal temperature of ’Makeris’ and’Zinia Barat’,there is little difference between ’Makeris’ and’Zinia Barat’.According to the results of comprehensive low temperature adaptability test,it is possible that the difference in cold resistance of 16 Bougainvillea varieties is small,and all of them can spend the winter in Changsha under certain cold protection measures.The study on the cutting propagation technology of Bougainvillea shows that the cutting effect of Bougainvillea is poor in the greenhouse in winter.1200 mg/L ABT1 and perlite can get a better cutting survival rate of 53.33%for ’Elizabeth Angus Varegata’,and 76.67%for ’Royal Bengal Red’ with 1200 mg/L IAA and perlite.At the same time,it was also found that Bougainvillea cuttings preferred high concentrations of growth hormone,and perlite had the best effect among the four substrates.The study on the garden application of Bougainvillea shows that the landscape effect of Bougainvillea is better,and it can form the landscape effect of rich layers and colors.The garden application of Bougainvillea in Changsha can be mainly used as Landscape trees,hedges and vertical greening.