| In this paper,we have studied the effect of nitrogen nutrition on growth and main active components of Isatis indigotica Fort.from different germplasm in the field experiment,as well as the effect of exogenous 5-aminolevulinic acid on growth,main active components and antioxidant enzyme activity of I.indigotica seedlings under salt stress in the pot test.Field experiment was going to analyze the dry matter accumulation,the growth of roots,the chlorophyll content and photosynthetic parameters of I.indigotica from five different germplasm by using seven nitrogen treatments with three repeats,which were nitrogen control(CK),NO3--N,NH4+-N,NH4+-N/NO3--N=75/25,NH4+-N/NO3-N=50/50,NH4+-N/NO3--N=25/75 and CO(NH2)2,respectively.Furthermore,we have also studied the response of alkaloids and polysaccharide of I.indigotica to different nitrogen treatments,and the contents of amino acid,protein and total nitrogen of aboveground of I.indigotica are explored.Pot experiment was going to explore the growth,main active components and antioxidase activities of I.indigotica from Anhui Bozhou and Shanxi Yuncheng populations by using five ALA treatments with three repeats,which were 0,12.5,16.7,25.0,and 50.0 mg·l-1 ALA,respectively.Thus providing a theoretical basis of metabolism under salt stress.Results obtained were as follows.1.There are many differences between the response of nitrogen treatment in different germplasm:Nitrogen treatment could effectively improve the chlorophyll content of I.indigotica,especially the Anhui Fuyang with nitrate nitrogen.Meanwhile,nitrogen treatment was also beneficial to improve its photosynthetic rate,stomatal conductance,transpiration rate and intercellular CO2 concentration,which significantly effected on the I.indigotica from Shanxi Shangluo.The main root diameter and the number of lateral root in the group of Gansu Zhangye and Shanxi Shangluo were the maximum number in NH4+-N/NO3--N=25/75 and NH4+-N/NO3--N=50/50,respectively.I.indigotica from Shanxi Shangluo in mixed fertilizer of ammonium and nitrate nitrogen(NH4+-N/NO3--N=75/25 and NH4+-N/NO3--N=50/50),grew well;While the group from Gansu Zhangye in the ammonium nitrogen and amide nitrogen processing conditions,underground biomass and total biomass had a larger accumulation.The treatment of amide nitrogen could improve the dry weight of roots of Anhui Bozhou,Gansu Zhangye,Anhui Fuyang and Shanxi Yuncheng.2.Nitrogen treatment could improve its indigo of I.indigotica leaves from Shanxi Yuncheng and Shanxi Shangluo.Meanwhile,the nitrogen treatment could also improve the total alkaloids of Anhui Bozhou and Shanxi Shangluo.The content of indigo,indirubin and total alkaloids increased in the group of Shanxi Yuncheng with NH4+-N/NO3--N=50/50,as well as Shanxi Yuncheng and Shanxi Shangluo with amide nitrogen.Compared with control,nitrogen treatment could effectively improve the(R,S)-epigoitrin content of I.indigotica roots from Gansu Zhangye and Shanxi Shangluo,while the polysaccharide content of I.indigotica roots from Anhui Bozhou.The(R,S)-epigoitrin content of I.indigotica roots from Gansu Zhangye was more higher than that of others in any treatment.3.Amide nitrogen has a inhibitory effect on the contents of amino acid,protein and total nitrogen in roots of I.indigotica;Ammonium nitrogen significantly improved the content of protein in roots of I indigotica from Gansu Zhangye;The biomasses multiplying contents of the main nitrogen compounds in roots of I.indigotica from Anhui Fuyang increased in nitrate nitrogen and ammonium nitrate mixed fertilizer(NH4+-N/NO3--N=75/25 and NH4+-N/NO3--N=50/50);While the biomasses multiplying contents of the main nitrogen compounds in roots of I.indigotica from Shanxi Shangluo increased obviously in NH4+-N/NO3--N=75/25.4.There were significant inhibition of seeds and seedlings growth of I.indigotica in 100 mmol·L-1 of NaCl stress.Germination rate,germination vigor,germination index,vigor index and water content were significantly decreased under salt stress,while malondialdehyde(MDA),content of soluble sugar,Cu-Zn superoxide dismutase(SOD)and peroxidase(POD)activities were increased significantly.Under salt stress,appropriate concentration ALA could improved germination rate,water content,activities of SOD,POD and CAT,meanwhile reduced the contents of soluble sugar and malondialdehyde(MDA),in which the germination rate and germination vigor were the maximum,and the activities of SOD、POD、CAT were the maximum by the treatment of 16.7 mg·L-1 ALA.It indicated that salt stress could obviously inhibit the seed germinating and seed growth of I.indigotica.Appropriate concentration ALA could effectively alleviate the damage to seed germinating and seed growth of I.indigotica under salt-stress and promote the salt resistance.5.Fresh weights in leaves and roots of I.indigotica seedling from Anhui Bozhou were lower than that of the blank control.Fresh weight in leaves of I.indigotica seedling from Shanxi Yuncheng was lower than that of the blank control,but the fresh weight in roots was higher than that of the control under salt stress.The contents of indigo and indirubin in leaves of seedling from Anhui Bozhou were lower than that of the blank control,but the(R,S)-epigoitrin content in roots was higher than that of the blank control.The content of(R,S)-epigoitrin in roots of seedling from Shanxi Yuncheng was higher than that of the blank control,but the indigo content in leaves of seedling from Shanxi Yuncheng was lower than that of the blank control.With different concentrations of ALA treatment,25mg·L-1 ALA can alleviate salt stress injuries,the fresh weights in leaves and roots of seedling from Anhui Bozhou were higher than that of the salt control.16.7 mg·L-1 ALA can promote the growth of seedling from Shanxi Yuncheng,which the fresh weights in leaves and roots were higher than that of the salt control.The contents of indigo and indirubin in leaves of seedling from Anhui Bozhou by treatments of 25mg·L-1 ALA and 50 mg·L-1 ALA were more higher,in which the 25 mg·L-1 ALA was the most significant.The contents of indigo and indirubin in leaves of seedling from Shanxi Yuncheng were more higher with the treatments of 12.5 mg·L-1 ALA and 16.7 mg·L-1 ALA,in which the content was the highest by the treatment of 12.5 mg·L-1 ALA.The(R,S)-epigoitrin contents in roots were the highest in Anhui Bozhou and Shanxi Yuncheng by the ALA treatment of 16.7 mg·L-1 and 12.5 mg·L-1,respectively.6.Superoxide dismutase(SOD),peroxidase(POD),catalase(CAT),glutamate synthase(GOGAT),nitrate reductase(NR)activities and the malondialdehyde(MDA)content increased in response to 100 mmol·L-1 NaCl in leaves of I.indigotica from Anhui Bozhou and Shanxi Yuncheng.However,chlorophyll relative content,Pn,Gs,Ci,Tr decreased in response to salt stress in leaves of I.indigotica from Anhui Bozhou and Shanxi Yuncheng.In all foliar application of ALA in leaves of I.indigotica from Anhui Bozhou,Pn,chlorophyll relative content,the MDA content,and the activities of SOD and POD were the highest in response to 50.0 mg·L-1 foliar application of ALA.GOGAT and NR activities were the highest in response to 25.0 mg·L-1 foliar ALA.Ci,Gs and Tr were the highest in S1 plants treated with by 12.5 mg·L-1 ALA.In leaves of I.indigotica from Shanxi Yuncheng,Pn,Gs,Tr,the MDA content,SOD,POD,CAT and NR activities treated with 16.7 mg·L-1 ALA were higher than that of other treatments.Chlorophyll relative content and GOGAT activity in leaves of I.indigotica from Shanxi Yuncheng treated with 50.0 mg·l-1 ALA were the highest among all treatments. |
PDF Full Text Request