作 者 ：吴晓艳 周守标 程龙玲 王欣 常琳琳
期 刊 ：植物营养与肥料学报 2012年 18卷 4期 页码：1026-1034
关键词：鸭儿芹幼苗；营养液浓度；生长因子；生理指标；叶绿素荧光参数；
Keywords:Cryptotaenia japonica seedling, concentration of nutrient solution, growth factor, physiological index, chlorophyll fluorescence parameter,
摘 要 ：为了探索适合鸭儿芹幼苗生长的营养液浓度，分别研究了6种山崎营养液浓度（1/12s、1/10s、1/8s、1/4s、1/2s和1s)对鸭儿芹幼苗生长及叶绿素荧光参数的影响。结果表明，在1/8s浓度下，鸭儿芹幼苗的各生长因子（株高、单株叶面积、茎粗、地上部鲜重、干重，地下部鲜重、干重，株鲜重、干重）均达到最大。壮苗指标随着营养液浓度的增大出现先上升后降低的趋势，在1/8s浓度下亦达到最大，且显著高于其它处理(P < 0. 05)。在1/12s～1/8s的浓度变化下，随着营养液浓度的增大，POD、CAT以及SOD活性在逐渐上升，MDA含量在逐渐降低，而在1/8s~1s的浓度变化下，随着营养液浓度的增大，POD、CAT以及SOD活性在逐渐降低，MDA含量在逐渐上升，在1/8s浓度下POD、CAT以及SOD活性达到最大，MDA含量达到最小。叶绿素a、叶绿素b及叶绿素总量出现先上升后下降的趋势，在1/8s浓度下均达到最大。1/4s～1s浓度，初始荧光（Fo）值均高于1/12s～1/10s处理，而最大荧光（Fm）、PSⅡ的潜在活性（Fv/Fo）、PSⅡ最大光化学效率（Fv/Fm）值分别低于1/12s～1/10s处理；1/8s浓度的Fo值达到最小，而Fm、Fv/Fo、Fv/Fm值达到最大。实验表明了营养液浓度对鸭儿芹幼苗具有双重作用，即低浓度下随浓度的升高，营养胁迫逐渐减低，促进幼苗生长；高浓度下随浓度的升高，营养胁迫逐渐增强，抑制幼苗生长。结果得出，采用1/8浓度的山崎配方是鸭儿芹幼苗生长的最适营养液浓度。
Abstract:In order to explore suitable nutrient concentration for the growth of Cryptotaenia japonica seedlings, the effects of six different concentrations of Yamasaki nutrient solution (1/12s, 1/10 s, 1/8s, 1/4s, 1/2s and full strength) on the growth, antioxidase activities and chlorophyll fluorescence parameters of Cryptotaenia japonica seedlings were investigated. The results show that the highest Cryptotaenia japonica seedlings‘ growth factors (plant height, leaf area, stem diameter, fresh and dry weights of shoots, fresh and dry weights of roost, fresh and dry weights of plants) are observed in the 1/8s Yamasaki nutrient solution. The seedling indexes are increased firstly and then declined with the increase of the nutrient solution concentration, and the maximal values of the seeding indexes are observed in the 1/8s nutrient solution, which are significantly higher than those of the other concentrations. When the concentrations of nutrient solution are between 1/12s~1/8s, the activities of POD, CAT and SOD are increased gradually with the increase of the nutrient concentration, while the MDA content is gradually decreased. However, the trends of the POD, CAT and SOD activities and as well as MDA content are contrary under the 1/8s~s nutrient concentrations. When the concentration of the nutrient solution is close to 1/8s, the activities of POD, CAT and SOD are highest, while the MDA content was the lowest. The contents of chlorophyll a, chlorophyll b and total chlorophyll are increased under the lower nutrient concentrations and decreased under the higher concentrations, and the physiological parameters are highest under the 1/8s nutrient solution. Under the 1/4s~full strength Yamasaki nutrient solution, the initial fluorescence (Fo) values are higher than those under the 1/12s～1/10s, while the maximal fluorescence (Fm), potential activity of PSII (Fv/Fo), and the maximal photochemical efficiency of PSII (Fv/Fm) are lower than those under the 1/12s~1/10s. The Fo value is lowest under the 1/8s nutrient concentration, while the values of Fm, Fv/Fo, Fv/Fm are the highest. Our findings suggest that the nutrient concentration plays dual roles on Cryptotaenia japonica seedlings, i.e. at the lower nutrient concentrations, seedling growths are accelerated with the increase of the concentrations due to alleviated nutrient stress, while seedling growths are inhibited the increase of the concentrations under the higher nutrient concentrations due to enhanced nutrient stress. The 1/8 strength Yamasaki nutrient solution is the optimal concentration for growth of Cryptotaenia japonica seedlings.
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