Taking one-year-old pot seedlings of cultivar‘Powderblue’ of rabbiteye blueberry ( Vaccinium ashei Reade) and superior strain A47 of cultivar ‘Southmoon’ of southern highbush blueberry ( V. corymbosum hybrids) as tested materials, effects of successive drought and flooding treatments on their growth and photosynthetic characteristics were researched. The results show that with prolonging of drought and flooding treatment times, damage symptoms of wilting or withering of stems and leaves, and leaf abscission of ‘Powderblue ’ and A47 seedlings are aggravated, and their growth indexes and photosynthetic parameters decrease obviously. In drought and flooding treatments for 35 d, their branch length, increment of branch length, dry weight of root, dry weight of stem and leaf, increment of plant growth and relative growth rate all are significantly lower than those of the control, while root/shoot ratio has no significant difference with that of the control;in drought and flooding treatments for 14 d, their net photosynthetic rate, stomatal conductance and transpiration rate of leaf all are significantly lower than those of the control, while generally difference in intercellar CO2 concentration is not significant with that of the control. With prolonging of drought and flooding stress times (0-35 d) , chlorophyll content index in leaf of ‘Powderblue’ and A47 seedlings decreases gradually and are generally lower than that of the control, while the maximal photochemical efficiency of PSⅡ and effective quantum yield of PSⅡ totally appear the trend of firstly increasing and then decreasing and all are lower than those of the control at the middle and late periods of drought and flooding treatments. It is suggested that drought and flooding treatments have an obvious inhibition on growth and photosynthetic characteristics of ‘Powderblue’ and A47 seedlings, but there are a certain difference in change range of their growth and photosynthetic characteristics under conditions of drought and flooding stresses, and their sensitivity to drought stress is stronger.%以兔眼蓝浆果(Vaccinium ashei Reade)品种‘粉蓝’(‘Powderblue’)和南方高丛蓝浆果(V. corymbosum hybrids)品种‘南月’(‘Southmoon’)优选系A47的1年生盆栽苗为供试材料,研究了持续干旱和淹水处理对它们的生长及光合特性的影响。结果表明：随着干旱和淹水处理时间的延长,‘粉蓝’和A47幼苗的枝叶萎蔫干枯和叶片脱落等受害症状加剧,生长指标和光合参数显著下降。干旱和淹水处理35 d,二者的枝长、枝长增长量、根系和茎叶干质量、植株增长量和相对生长速率均显著低于对照,根冠比与对照无显著差异；干旱和淹水处理14 d,二者的叶片净光合速率、气孔导度和蒸腾速率显著低于对照,而胞间CO2浓度总体上与对照无显著差异或略高于对照。随干旱和淹水处理时间的延长(0~35 d),‘粉蓝’和A47幼苗叶片的叶绿素含量指数逐渐下降且总体上小于对照, PSⅡ最大光化学效率和有效光量子产量总体上呈先升后降趋势且在处理的中后期均低于对照。研究结果表明：干旱和淹水处理对‘粉蓝’和A47幼苗的生长和光合特性均有明显的抑制作用,但干旱和淹水胁迫条件下二者的生长和光合特性变化幅度有一定差异,且二者对干旱胁迫的敏感性较强。
展开▼
