盐碱胁迫下藜麦种质幼苗生理特性及耐盐碱性评价

Response of seedling growth and physiological characteristics of quinoa germplasm to saline-alkali stress and evaluation of saline-alkali tolerance

以藜麦为研究对象,使用盆栽育苗法,设置0(CK)、150、300 mmol·L^(-1)3个混合盐碱(NaCl∶NaHCO_(3)=1∶1)浓度处理,通过测定幼苗鲜质量、干质量及叶片叶绿素、可溶性糖、脯氨酸、丙二醛含量、抗氧化酶活性等生长及生理指标,研究盐碱胁迫对10份藜麦(Q1~Q10)种质幼苗生长和生理特性的影响。结果表明:随盐碱胁迫程度加剧,幼苗的株高、根长较对照有少量增高,Q1的150 mmol·L^(-1)和300 mmol·L^(-1)处理较CK增高3 cm,而鲜质量相较CK有明显的下降趋势,在300 mmol·L^(-1)至150 mmol·L^(-1)减少0.19 g;叶片叶绿素含量中的Q6由CK的2.7 mg·g^(-1)在150 mmol·L^(-1)时上升至4 mg·g^(-1),在300 mmol·L^(-1)时下降至2 mg·g^(-1);Q1的可溶性糖由CK的30.8 mg·g^(-1)在150 mmol·L^(-1)时升至37.59 mg·g^(-1),在300 mmol·L^(-1)时升高至89.84 mg·g^(-1),Q1的可溶性蛋白含量由CK的30.87 mg·g^(-1)升至150 mmol·L^(-1)的37.59 mg·g^(-1),在浓度为300 mmol·L^(-1)时达到最大为89.84 mg·g^(-1)。藜麦的幼苗叶内脯氨酸的含量在各盐碱处理下均显著高于CK,其中Q7由CK的95.12μg·g^(-1)升高至300 mmol·L^(-1)时的216.17μg·g^(-1),当盐碱浓度为150 mmol·L^(-1)时藜麦幼苗丙二醛含量与对照间差异不显著,其中Q1的超氧化物歧化酶活性由CK的4.76 U·g^(-1)升高至5.94 U·g^(-1)后下降至4.91 U·g^(-1)、过氧化物酶活性由CK的0.13 U·g^(-1)升至3.66 U·g^(-1),在300 mmol·L^(-1)下降至0.56 U·g^(-1)、过氧化氢酶活性由CK的2.13 U·g^(-1)升高至3.36 U·g^(-1),在300 mmol·L^(-1)下降至2.5 U·g^(-1)。整体因浓度的增加而表现出先增强后降低的趋势。综合评价10份供试材料,耐盐碱性最强的为HZLM-15-1、其次为HJL-33-1,对盐碱敏感的材料为HJL34-1和LZLM-4。

Taking quinoa as the research object,potted seedling rearing method was used,and 3 mixed salt and alkali(NaCl∶NaHCO_(3)=1∶1)concentrations were set at 0(CK),150 and 300 mmol·L^(-1).The effects of saline-alkali stress on the growth and physiological characteristics of quinoa germplasm seedlings were studied by measuring fresh weight,dry weight,leaf chlorophyll,soluble sugar,proline,malondialdehyde content and antioxidant enzyme activity.The results showed that the plant height and root length of Q1 increased by 3 cm from 150 mmol·L^(-1)to 300 mmol·L^(-1),while the fresh weight decreased by 0.19 g from 300 mmol·L^(-1)to 150 mmol·L^(-1)compared with the control.The content of Q6 in leaf chlorophyll increased from 2.7 mg·g^(-1)at 150 mmol·L^(-1)to 4 mg·g^(-1)and decreased to 2 mg·g^(-1)at 300 mmol·L^(-1).The soluble sugar of Q1 increased from 30.8 mg·g^(-1)to 37.59 mg·g^(-1)at 150 mmol·L^(-1)for CK and 89.84 mg·g^(-1)at 300 mmol·L^(-1).The soluble protein content of Q1 increased from 30.87 mg·g^(-1)for CK to 37.59 mg·g^(-1)for 150 mmol·L^(-1)and reached a maximum of 89.84 mg·g^(-1)when the concentration was 300 mmol·L^(-1).The content of proline in leaves of quinoa seedlings was significantly higher than that of the control under all salt and alkali treatments,and Q7 increased from 95.12μg·g^(-1)for CK to 216.17μg·g^(-1)for 300 mmol·L^(-1).There was no significant difference in malondialdehyde content between quinoa seedlings and the control when the salt and alkali concentration was 150 mmol·L^(-1).The superoxide dismutase activity of Q1 increased from 4.76 U·g^(-1)in CK to 5.94 U·g^(-1)and then decreased to 4.91 U·g^(-1),and the peroxidase activity increased from 0.13 U·g^(-1)in CK to 3.66 U·g^(-1).Catalase activity increased from 2.13 U·g^(-1)to 3.36 U·g^(-1)at 300 mmol·L^(-1)and then decreased to 2.5 U·g^(-1)at 300 mmol·L^(-1).With the increase of concentration,the overall concentration showed a trend of first increasing and then decreasing.Based on the comprehensive evaluation,HZLM-15-1 was the most salt-alkali resistant material,followed by HJL-33-1,and HJL34-1 and LZLM-4 were the most salt-alkali sensitive materials.