外源锌对白术种子萌发及幼苗生长的影响

以白术种子为试材,采用盆栽试验法,研究外源锌对白术种子萌发和幼苗生长的影响,以期为白术科学施锌和种苗高效繁育提供参考依据。结果表明:外源锌对白术幼苗生长具有低浓度(≤100 mg·L^-1)促进,高浓度(200 mg·L^-1)抑制的效果。其中100 mg·L^-1的锌处理对白术种子萌发和幼苗生长的促进效果最好,与对照相比,提高了白术幼苗的根长、株高、叶片数和鲜质量,增幅分别达到68.3%、29.1%、21.2%和20.0%;幼苗叶绿素a、叶绿素b、总叶绿素和类胡萝卜素含量也显著高于对照,增幅分别为16.7%、26.2%、19.4%和5.9%。此外,100 mg·L^-1锌处理显著提高白术幼苗叶片可溶性蛋白质(SP)含量,降低过氧化氢酶(CAT)活性和超氧化物歧化酶(SOD)活性,减少叶片可溶性糖含量(SS)和丙二醛(MDA)含量。200 mg·L^-1锌处理对白术幼苗的生长具有显著的抑制作用,根长、株高、鲜质量、干质量及叶绿素含量均显著低于对照。综上所述,外源锌对白术幼苗生长具有典型的剂量效应,施用100 mg·L^-1的锌肥对白术幼苗生长的促进效果最佳。

Effects of Exogenous Zinc on Seed Germination and Seedling Growth of Atractylodes macrocephala

Taking Atractylodes macrocephala as test material,the effects of exogenous zinc(Zn)on seed germination and seedling growth of Atractylodes macrocephala were explored through a pot experiment,in order to provide reference for rational zinc application and efficient breeding of A.macrocephala.The results showed that the growth of A.macrocephalaseedlings was promoted by low Zn levels(≤100 mg·L^-1)and inhibited by high levels(200 mg·L^-1).100 mg·L^-1Zn treatment had the best effect on the seed germination and seedling growth of A.macrocephala.Compared with the control,100 mg·L^-1Zn treatment significantly increased the root length,plant height,leaf number and fresh weight of A.macrocephala seedlings by 68.3%,29.1%,21.2% and 20.0%,respectively.The content of chlorophyll a,chlorophyll b,total chlorophyll and carotenoid in A.macrocephalaseedling leaves under 100 mg·L^-1Zn treatment were also significantly increased by16.7%,26.2%,19.4% and 5.9%,respectively,compared with the control.Moreover,the content of soluble protein(SP)in A.macrocephalaseedling leaves was significantly increased while the soluble sugar(SS)and malondialdehyde(MDA)were decreased under the 100 mg·L^-1Zn treatment,compared with the control.Meanwhile,the activities of catalase(CAT)and superoxide dismutase(SOD)in A.macrocephalaseedling leaves were also significantly decreased under the 100 mg·L^-1Zn treatment,compared with the control.However,the root length,plant height,fresh weight,dry weight and chlorophyll content of A.macrocephala seedlings under 200 mg· L^-1Zn treatment were significantly lower than those of the control.In conclusion,Zn had a typical dose effect on the growth of A.macrocephalaseedlings,and 100 mg·L^-1Zn should be recommended.