外源硅对NaCl胁迫下小麦幼苗生长及光合特性的影响

为探讨外源硅对小麦幼苗耐盐性的调节作用,以抗盐小麦品种德抗961和非抗盐小麦品种泰山9818为材料,通过水培试验,研究了外源硅对NaCl胁迫下小麦幼苗生长、叶绿素含量和光合特性的影响。结果表明,在100mmol·L-1 NaCl胁迫下,随着外源硅浓度(0~3.0mmol·L-1)的增加,德抗961和泰山9818的株高、次生根数量、茎叶干重、根干重不断增加,叶片叶绿素、叶绿素a和叶绿素b含量先降后升,净光合速率及气孔导度逐渐升高,细胞间隙CO2浓度逐渐下降,气孔限制值先升后降。说明适量施硅可显著提高小麦抗盐性。

Effect of Silicon on the Biomass and Photosynthetic Characteristics of Wheat Seedlings under NaCl Stress

In order to investigate the effect of silicon on improving wheat salt resistance,with two wheat cultivars,Dekeng 961 (salt-resistant) and Taishan 9818 (salt-sensitive) as materials,the influences of different concentration K₂SiO₃ on the biomass,chlorophyll content,and photosynthetic characteristics of wheat seedlings under NaCl stress were investigated. The results showed that with the increase of K₂SiO₃ concentration,the plant height,number of secondary root,shoot dry weight,and root dry weight of the two wheat cultivars all were increased,the contents of chlorophyll,chlorophyll a,chlorophyll b of the two cultivars were decreased at first and then increased,the net photosynthetic rate and stomatal conductance were increased gradually,the intercellular CO₂ concentration was decreased continuously,the stomatal limitation value appeared to have a decline trend after an initial ascent. It indicated that proper amount of silicon could improve salt resistance and decrease the salt injury of wheat seedlings.