纳米氧化锌对花生幼苗生长和光合性能的影响

Effects of ZnO nanoparticles on growth and photosynthetic performance of peanut seedlings

  • 摘要: 【目的】探究不同浓度的纳米氧化锌(ZnO NPs)对花生幼苗生长和光合性能的影响,为ZnO NPs在花生生产中的研究和应用提供理论和实践依据。【方法】采用水培法对花生品种豫花37的幼苗分别进行不同浓度(0、 0.01、0.05、 0.10和0.50 mmol/L)和不同时间 (5和10 d)的ZnO NPs处理,测定花生幼苗的形态指标、气体交换参数、叶绿素荧光参数、叶绿素相对含量和氮平衡指数等,并对以上指标进行统计分析。【结果】随着ZnO NPs处理浓度的增加和时间的延长,花生幼苗的鲜重、干重、总根长、总根表面积、净光合速率、气孔导度、光化学性能指数、氮平衡指数和叶绿素相对含量等指标均呈逐渐降低或波动降低趋势,蒸腾速率先升高后降低,类黄酮相对含量逐渐增加。处理10 d时,0.10和0.50 mmol/L ZnO NPs处理使幼苗的鲜重、根干重、净光合速率和光化学性能指数分别显著降低26.3%~41.7%、16.7%~41.7%、 50.9%~80.7%和46.7%~59.2% (P<0.05,下同);不同浓度和时间的ZnO NPs处理使幼苗的氮平衡指数显著降低19.1%~73.9%。相关分析结果表明,花生幼苗的鲜重和干重与总根长、净光合速率、蒸腾速率、叶绿素相对含量呈显著或极显著 (P<0.01,下同)正相关,幼苗鲜重还与光化学性能指数和氮平衡指数呈极显著正相关。【结论】 ZnONPs抑制了花生幼苗根系对水分和氮素的吸收,同时抑制幼苗叶片的叶绿素合成、损伤光系统Ⅱ结构,降低幼苗的净光合速率,使幼苗的水分和养分供应不足,从而抑制幼苗生长。

     

    Abstract: 【Objective】To investigate effects of ZnO nanoparticles(ZnO NPs)of different concentrations on growth and photosynthetic performance of peanut seedlings,so as to provide a theoretical and practical basis for research and application of ZnO NPs in peanut production.【Method】 Seedlings of peanut cultivar Yuhua 37 were treated with ZnO NPs at different concentrations(0,0.01,0.05,0.10,0.50 mmol/L)for different times(5 and 10 d)by hydroponic method.Morphological indexes,gas exchange parameters,chlorophyll fluorescence parameters,chlorophyll relative content and nitrogen balance index of peanut seedlings were measured,and statistical analysis were conducted on above parameters.【Result】With the increase of ZnO NPs concentration and the extension of time,fresh weight,dry weight,total root length,total root surface area,net photosynthetic rate,stomatal conductance,photochemical property index,nitrogen balance index and chlorophyll relative content of peanut seedlings all showed a gradual or fluctuating decreasing trend.Transpiration rate first increased and then decreased,and the relative content of flavonoid gradually increased.After 10 d of treatment,fresh weight,root dry weight,net photosynthetic rate and photochemical performance index of seedlings treated with 0.10 and 0.50 mmol/L ZnO NPs were significantly decreased by 26.3%-41.7%,16.7%-41.7%,50.9%-80.7% and 46.7%-59.2%,respectively(P<0.05,the same below).The nitrogen balance index of seedlings was significantly decreased by 19.1%-73.9% under ZnO NPs treatment of different concentrations and time.Correlation analysis showed that fresh weight and dry weight of the peanut seedlings were significantly or extremely significantly(P<0.01,the same below)positively correlated with total root length,net photosynthetic rate,transpiration rate and relative chlorophyll content.Fresh weight of seedlings was also extremely significantly positively correlated with photochemical performance index and nitrogen balance index.【Conclusion】 ZnO NPs inhibits the absorption of water and nitrogen by the roots of peanut seedlings,and at the same time it inhibits synthesis of chlorophyll in leaves,damages the structure of photosystem Ⅱ,reduces the net photosynthetic rate of seedlings and makes supply of water and nutrients insufficient,thus inhibiting the growth of peanut seedlings.

     

/

返回文章
返回