钙浓度对马尾松幼苗生长和生理特征的影响

Effects of Calcium Concentration on Growth and Physiological Characteristics of Pinus massoniana Seedling

[目的]在不同供Ca2+水平下对马尾松幼苗生长及生理特性进行研究,以确定适宜马尾松生长的钙浓度,为马尾松人工林培育及合理施用钙肥提供参考。[方法]以半年生马尾松幼苗为试材,采用温室内砂培,研究不同供Ca2+水平(0.0、0.4、1.0、2.0、3.0、4.0 mmol·L^(-1)(CK))对马尾松生长及生理指标的影响。[结果]不同供Ca2+水平处理5个月后,在Ca2+水平为1.0、2.0 mmol·L^(-1)时,马尾松幼苗的株高增量和地径增量较高,其中,2.0 mmol·L^(-1)Ca2+水平的株高增量和地径增量最高。马尾松幼苗对Ca2+水平适应能力强弱顺序为2.0>1.0>0.4>3.0>0.0>4.0 mmol·L^(-1)(CK)。在不同生长期内,随着供Ca2+水平的增加,马尾松针叶中ROS(O2-产生速率、H2O2浓度)、MDA含量、抗氧化酶(SOD、POD、CAT和APX)活性、抗氧化物质(GSH、As A)含量、脯氨酸含量均先降低后增加,最小值均在1.0 mmol·L^(-1)或2.0 mmol·L^(-1)处理中;类胡萝卜素含量先增加后降低,其最高值均在2.0 mmol·L^(-1)处理中。马尾松幼苗的株高增量和地径增量与类胡萝卜素含量关系不明显,而与其他生理指标均呈显著负相关。[结论]马尾松幼苗适宜在1.0 2.0 mmol·L^(-1)Ca2+水平的环境中生长。在马尾松林地中,应对土壤有效钙含量进行测定,并结合植株的生长和生理特征进行综合评价后,科学合理施肥以提高生产力。

[ Objective ] To select the optimal Ca^2 ＋concentration for Pinus massoniana seedling growth and to provide evidence for plantation cultivation and rational application of calcium fertilization by studying the effects of Ca^2＋ concentration on growth and physiological characteristics of P. massoniana seedlings. [ Method ] A greenhouse sand culture experiment was carried out to study the growth and physiological characteristics of half-year-old seedlings of P. massonianain different Ca^2＋ concentrations （0.0, 0.4, 1.0, 2.0, 3.0 mmol ·L^-1 and 4.0 mmol ·L^-1 （CK））. [Result]The results showed that both the height and stem increments of P. massoniana under 1.0-2.0 mmol ·L^-1 Ca^2＋ for five months were higher, and seedlings grew best in 2.0 mmol·L^-1 Ca^2＋ The adaptable strong-to-weak sequence of P. massoniana seedlings was 2.0, 1.0, 0.4, 3.0, 0.0 mmol·L^-1 and 4.0 mmol·L^-1（CK） of Ca^2＋. At different growth periods, these indices of pine needles, including 02 -generation rate, H2O2 content, protective enzyme activities （SOD, POD, CAT and APX）, the contents of GSH, AsA and proline, decreased at first and then increased subsequently along with the increasing Ca^2＋ concentration, and all minimums occurred at 1.0 mmol ·L^-1 or 2.0 mmol·L^-1 of Ca^2＋. [ Conclusion] P. massoniana seedlings is suitable to grow in the soil with Ca^2＋ concentration of 1.0-2.0 mmol·L^-1 according to the experiment results. Based on comprehensive analysis to soil available calcium of P. massoniana forestland, the growth and physiological characteristics of seedlings, it is necessary to applying rationally calcium fertilization so as to boost the productivity of P. massoniana.