纳米二氧化硅对水稻种子萌发及分蘖期生长和光合特性的影响

Effects of SiO_(2) nanoparticles on seed germination,growth and photosynthetic properties of rice at tillering stage

为探究纳米二氧化硅(SiO_(2)NPs)对水稻种子萌发、生长、生理和光合作用的影响,为SiO_(2)NPs应用于农业生产提供参考,采用完全随机设计,分别使用0.01、0.10、1.00、10.00 g/L的SiO_(2)NPs(30 nm)水分散液对水稻种子和叶片表面进行处理,依次以T_(1)、T_(2)、T_(3)、T_(4)表示,并以去离子水作为对照(CK),研究SiO_(2)NPs对水稻种子发芽情况以及分蘖期水稻株高、分蘖数、生物量、可溶性多糖含量、可溶性蛋白质含量、游离氨基酸含量、总酚含量、叶绿体色素含量、光合速率、光合荧光参数的影响。结果表明,T_(3)水稻种子发芽势、发芽指数、活力指数分别比CK高6.6%、32.7%、43.4%;T_(2)水稻根生物量比CK高43.6%,T_(3)水稻茎、叶生物量分别比CK高143.9%、15.2%;T_(3)水稻叶片可溶性多糖、总酚含量分别比CK高107.1%、26.7%;T_(4)水稻叶绿素a、叶绿素b、类胡萝卜素、叶绿素总含量分别比CK高21.3%、60.3%、45.6%、30.6%;T_(3)水稻叶片光合速率比CK高32.4%,光反应过程中光化学淬灭系数qP、qL分别比CK高68.5%、61.7%,相对光电子传导速率ETR和实际光化学量子产量Y(Ⅱ)均比CK高69.7%。建议使用0.10~1.00 g/L的SiO_(2)NPs对水稻进行浸种及分蘖期处理。

To investigate the effects of silica nanoparticles(SiO_(2)NPs)on rice seed germination,growth and photosynthesis,and provide a reference for the application of SiO_(2)NPs in agricultural production,a completely randomized design was used,the surface of rice seeds and leaves was treated with 0.01,0.10,1.00 and 10.00 g/L aqueous dispersions of 30 nm SiO_(2) NPs,expressed sequentially as T_(1),T_(2),T_(3)and T_(4),and deionized water was taken as control(CK).The effects of SiO_(2)NPs on rice seed germination,growth indices and photosynthetic characteristics such as plant height,tillering number,biomass,soluble polysaccharides content,soluble proteins content,free amino acids content,total phenols content,pigment content of chloroplast,photosynthetic rate and photosynthetic fluorescence parameters at tillering stage were investigated.The results showed that the germination potential,germinate index and vitality index of rice seeds under T_(3)increased by 6.6%,32.7% and 43.4% respectively compared to CK.Root biomass of rice under T_(2) increased by 43.6% compared to CK,while stem and leaf biomass of rice under T_(3)increased by 143.9% and 15.2% respectively.The contents of soluble polysaccharides and total phenols of rice leaves under T_(3) were 107.1% and 26.7% higher than those in CK,respectively.The contents of chlorophyll a,chlorophyll b,carotenoid and total chlorophyll of rice leaves under T_(4) were 21.3%,60.3%,45.6% and 30.6% higher than those in CK,respectively.Photosynthetic rate,the photochemical quenching coefficients qP and qL during the light reaction process,relative photoelectron conduction rate ETR and actual photochemical quantum yield Y(Ⅱ)of rice leaves under T_(3) increased by 32.4%,68.5%,61.7%,69.7% and 69.7% compared to CK respectively.It was recommended to use0.10~1.00 g/L SiO_(2)NPs for rice seed soaking and tillering stage treatment.