Preliminary Study About Photosynthetic Characteristics Of Different Blueberry Varieties

Three years old ‘Northland’, ‘Duke’, ‘Sierra’ and ‘Berkeley’ as the material in this study, which under natural condition or water stress or soil pH stress, than compare the photosynthesis, chlorophyll fluorescence parameters, chlorophyll content of different blueberry varieties, and observation their microstructure, Analysis of the strength of its intrinsic photosynthetic capacity and their resist capacity to soil pH stress and water stress, For breeding salinity, drought-resistant varieties of blueberries provide theoretical reference, provide theoretical guidance about the actual production, cultivation and management of blueberry varieties tested.The main conclusions as flows:(1)Under natural condition, the photosynthetic capacity of ‘Sierra’ better than others, but ‘Sierra’ is the most susceptible to high light, temperature and other external environment; The high light-resistant ability of ‘Duke’ better than others, but its resilience ability is weak when its self- mechanism is damaged by adversity; The self-protection mechanism of ‘Northland’ better than others.(2)Under water stress condition, it is equally that every index’s trend of four blueberry varieties tested. Under mild water stress, each index of ‘Northland’ change the smallest, indicating that ‘Northland’ has a certain ability to adapt mild water stress; ‘Sierra’ shows a strong drought resistance; under water stress ’Berkeley’ has a good self-protection mechanism, to make their own optical system reduces the extent of the damage.(3)Under soil pH stress, four blueberry varieties tested chlorophyll content, Pn, chlorophyll fluorescence parameters have significantly changed. ‘Northland’ and ‘Sierra’ is sensitive to soil pH, ‘Northland’ the ability of processing excess light is better; ‘Duke’ the ability of processing excess light is weak, but its own body has strong light capability; Taken together ’Berkeley’ has better resistance to stress the ability of soil pH. Four blueberry varieties tested all like acidic soil, they can grow normally with soil pH between 4.00 to 5.00, ‘Berkeley’ and ‘Duke’ can adapt to a wider range of soil pH, which can still grow normally when soil pH up to 5.80 growth.