NaCl和Na2CO3胁迫对枸杞幼苗生长和光合特性的影响

摘要

以黑果枸杞‘黑杞1号’和宁夏枸杞‘宁杞7号’的1年生幼苗为试材,用NaCl和Na2CO3溶液进行处理,研究盐胁迫条件下,枸杞幼苗生长、光合作用和叶绿素荧光参数的变化.结果表明,2种枸杞在NaCl和Na2CO3胁迫下,幼苗生长、光合作用和叶绿素荧光参数的变化趋势基本相同,但不同盐不同品种间幼苗生长、光合作用和叶绿素荧光参数值存在差异.生长特性方面,盐胁迫主要影响株高和基径;在光合和叶绿素荧光特性方面,盐胁迫主要影响的参数有Pn、Gs、Ci、Tr、ΦPSⅡ、Fo、Fm、Fv/Fm、CqP、CqN、叶绿素a含量、叶绿素b含量、总叶绿素含量,其中,Pn、Gs、Ci、Fo、CqP、ΦPSⅡ和总叶绿素含量与对照相比差异显著,Tr、Fm、Fv/Fm、CqN、叶绿素a含量和叶绿素b含量与对照相比无显著差异.NaCl胁迫后, ‘黑杞1号’和‘宁杞7号’幼苗的生长量、光合速率分别在1.3 mol·L-1和1.2 mol·L-1时达到最高值,在1.5 mol·L-1时,达到耐盐极限值;Na2CO3胁迫后, ‘黑杞1号’和‘宁杞7号’幼苗的生长量、光合速率在0.1 tmol·L-1时达到最高值,分别在0.4 mol·L-1和0.5 mol·L-1达到耐盐极限值.所以, ‘黑杞1号’耐盐能力强于‘宁杞7号’,且Na2CO3对枸杞幼苗影响显著大于NaCl.%One-year-old seedlings of Lycium ruthenicum ‘Heiqi No.1’ and L.barbarum ‘Ningqi No.7’ were selected as test materials,and changes of growth and photosynthesis and chlorophyll fluorescence parameters in seedlings were researched under the stresses of NaCl and Na2CO3.The results showed that change trends of growth,photosynthesis and chlorophyll fluorescence parameters in the two cultivars of seedlings were basically the same,under the stresses of NaCl and Na2CO3,but the indexes among different cultivars Under different salt stresses had significant differences.At the aspect of growth characteristics,salt stress mainly affects plant height and ground diameter;at the aspect of photosynthetic and chlorophyll fluorescence characteristics,salt stress mainly affects the parameters of Pn,Gs,Ci,Tv ΦPS Ⅱ,Fo,Fm,Fv /Fm,CqP,CqN,chlorophyll a content,chlorophyll b content and total chlorophyll content.Among the parameters,compared with the contrast seedlings,Pn,Gs,Ci,Fo,CqP,ΦPS Ⅱ and total chlorophyll had significant differences,while Tv Fm,Fv/Fm,CqN,chlorophyll a content and chlorophyll b content had no significant differences.In addition,increment and photosynthetic rate of ‘Heiqi No.l’ and ‘Ningqi No.7’ seedlings reached the highest values Under the stress of 1.3 and 1.2 mol · L-1 NaCl,respectively,and the seedlings reached the limit values of salt tolerance under the stress of 1.5 mol · L-1 NaCl.While increment and photosynthetic rate of ‘Heiqi No.l’ and ‘Ningqi No.7’ seedlings reached the highest value under the stress of 0.1 mol · L-1 Na2CO3,and the seedlings reached the limit values of salt tolerance under the stress of 0.4 and 0.5 mol · L-1 Na2CO3,respectively.So ‘Heiqi No.l’ had stronger salt tolerance than ‘Ningqi No.T,and effects of Na2CO3 on L.chinese seedlings was significantly greater than that of NaCl.