外源钙对盐胁迫下匍枝萎陵菜生长及生理特性的影响

采用盆栽试验法,对匍枝萎陵菜进行盐胁迫处理,同时施用不同浓度氯化钙,通过对新梢生长量,叶片中丙二醛(MDA)、可溶性糖、脯氨酸(Pro)的含量以及超氧化物歧化酶(SOD)活性等指标进行测定分析,来探讨其耐盐能力及氯化钙的作用。结果表明:随盐浓度升高,匍枝萎陵菜新梢生长量下降,叶片中MDA和Pro含量增加,叶片中SOD活性、可溶性糖含量均呈先升后降趋势。各盐浓度处理下,随外源钙浓度的增加,新梢生长量、SOD活性、可溶性糖含量、脯氨酸含量基本呈现先升后降趋势,MDA含量在低盐浓度下(3,4mg·g-1)呈下降趋势,在高盐浓度下(5,6mg·g-1)呈现先降后升趋势。综合各测定指标及外部形态的表现认为:匍枝萎陵菜可以在含盐量4.00mg·g-1及以下的土壤中正常生长;氯化钙对匍枝萎陵菜遭受盐胁迫有一定缓解作用,在较低盐浓度下(3~4mg·g-1),CaCl2缓解作用较明显,以20mmol·L-1的浓度较适宜;较高盐浓度下(5~6mg·g-1)CaCl2的作用不明显。

Effects of Exogenous Calcium on the Growth and the Physiological Properties of Potentilla flagellaris Willd. ex Schlecht Under Salt Stress

Potted flagellar cinquefoil (Potentilla flagellaris Willd. ex Schlecht.)treated with salt and calcium chloride with distinctive concentrations was studied to understand its salt tolerance and to determine calcium chloride functions in the mitigation of salt stress. Indexes including shoot growth increment, MDA, Pro and soluble sugar contents and SOD activity in the leaves were analyzed in the experiment. The results showed that with the increasing of salt concentration, shoot growth increment declined; MDA and Pro contents in the leaves increased while SOD activity and soluble sugar contents tended to increased at the beginning and decreased afterwards. With the increasing concentration of exogenous calcium, shoot growth increment, SOD activity, soluble sugar and Pro contents increased at first and then decreased in any salt concentration treatment. MDA content tended to decline in low salt concentration (3 ,4 mg·g ~(-1 )) but had a tendency to drop at first and then to go-up in high salt concentration (5 ,6 mg·g ~(-1 )). Conclusions could be drown from the indexes analyzed and field observation that flagellar cinquefoil will grow vigorously in the soil in which salinity is under 4 mg·g ~(-1) ; slat stress can be mitigated by calcium applying to a certain degree; the calcium functions well under low salinity (3 ~ 4 mg·g ~(-1) )but will not act obviously under high salinity(5 ~ 6 mg·g ~(-1) ). Appropriate applying concentration of CaCl 2 was 20 mmol·L ~(-1 ).