Effects Of Nutrient Solution Formula On Growth And Quality Of The Potted Water Dropwort(Oenanthe Stolonifera(Roxb) Wall.)

Water dropwort(Oenanthe stolonifera(Roxb)Wall.)is a perennial aquatic herb,which is native to China and southeast Asia.The edible part of water dropwort are the tender stem and petiole,which is rich in cellulose,vitamins and mineral nutrition,and also contains higher functional substances such as flavonoids and polyphenols,which have the medicinal value of protecting liver,improving immunity and improving diarrhea.There are mainly cultivation methods such as soil softening cultivation,wet cultivation,shallow water cultivation,deep water cultivation,deep planting softening cultivation,summer sunshade net covering cultivation,and so on.However,there are relatively few in-depth studies on nutrient solution cultivation of water dropwort,especially on nutrient culture pot.In this paper,the formula of nutrient solution in water dropwort pot was screened and optimized through the experiment of nutrient solution in water dropwort pot,and the effect of nutrient solution on the growth and quality of water dropwort pot was preliminarily studied by using a wide range of targeted metabolomics technology,so as to provide theoretical basis and technical guidance for water dropwort pot.The main research results are as follows:1.In spring,seven kinds of classical formula of nutrient solution were selected to cultivate water dropwort,and Hoagland formula was used as the control.The yield of water dropwort cultivated with nutrient solution formula was significantly different,and the yield of the first crop was higher than that of the second crop.In addition to the Dutch greenhouse cultivation formula,other formulas of the first crop water dropwort of chlorophyll content were higher than the second crop.Flavonoids,total phenol content of leaves,respectively was 2～3.5 times of petiole,3～6.5 times of petiole.Leaves and petioles of IDF content were higher than 55%and 48%respectively,the first crop of leaf of SDF content were higher than petiole,the second crop of water dropwort of SDF content were higher than the first.In autumn,the yield of water dropwort was significantly different,and the contents of VC,flavonoids,total phenols,IDF,SDF and TDF were higher than 40 μg/g,1.55 mg/g FW,8.5 mg/g FW,54%,6%and 60%,respectively.Through the comprehensive analysis of analytic hierarchy process,it is concluded that the yield and quality of water dropwort cultivated in spring and autumn of yamazaki(Cryptotaenia japonica Hassk.)formula is higher,and it is determined to be the best formula of classic nutrient solution for pot cultivation of water dropwort.2.On the basis of yamazaki(Cryptotaenia japonica Hassk.)formula,five K+ concentrations of 3.5,7.8.49,9.97 and 11.46 mmol/L were set,and 7 mmol/L was used as the control.Five NO3-concentrations of 7,8,9,10 and 11 mmol/L were set,and 8 mmol/L as the control.The yield of potted water dropwort with the concentration of 3.5 mmol/L K+was the lowest,and the other concentration was slightly lower than the control.The VC content of water dropwort in pot with different concentrations was 4.5%higher than that in the control group.The content of flavonoids and total phenols in pot with 3.5 mmol/L K+ concentration was the highest,and DPPH radical scavenging rate was decreased compared with that in the control group.Through the comprehensive analysis of analytic hierarchy process,it is concluded that the comprehensive evaluation value increases first and then decreases with the increase of K+ concentration,and 7,8.49 mmol/L cultivation of water dropwort comprehensive evaluation value is relatively high The maximum yield of 9 mmol/L NO3-concentration potted water dropwort was 310.70 g,9.7%higher than CK.The VC content of potted water dropwort in 9 and 10 mmol/L were 4.3%and 0.5%higher than that of CK,respectively,the flavonoids,total phenols and DPPH radical scavenging rate of potted water dropwort in 7 mmol/L were the highest,and the content of IDF was all higher than that of the control group.With the increase of NO3-concentration of nutrient solution,the SDF content of water dropwort presented an increasing trend,and TDF showed an increasing trend after an initial decrease.Through the comprehensive analysis of analytic hierarchy process,it is concluded that the cultivation of water dropwort with 9 mmol/L NO3-concentration has the highest comprehensive evaluation value,which is determined to be the optimal NO3-concentration of nutrient solution potted water dropwort3.On the basis of the selected formula of yamazaki(Cryptotaenia japonica Hassk.),two NO3-concentrations of 8 and 9 mmol/L and four K+concentrations of 5.61,7,7.59 and 8.49 mmol/L were set for optimal cultivation,with soil cultivation as the control.The concentration optimization of nutrient solution NO3-and K+ can improve the yield and quality of water dropwort.The yield,chlorophyll,flavonoids,total phenols and DPPH radical scavenging rate of potted water dropwort in nutrient solution were significantly higher than those in the control group,and the contents of IDF,SDF and TDF were higher than 52%,10%and 67%,respectively Through the comprehensive analysis of analytic hierarchy process,it is concluded that 9 mmol/L of NO3-concentration,7 mmol/L of K+ concentration of potted water dropwort yield the highest and good quality,determined as the best formula of water dropwort potted nutrient solution.4.Through the widely targeted metabolome technique,analysis the potted water dropwort of nutrient solution and soil.A total of 485 metabolites,including flavonoids,phenolic acids,amino acids and derivatives,lipids,organic acids,nucleotides and derivatives,lignans and coumarins,alkaloids,terpenoids,were detected in the above-ground part of water dropwort.113 differential expressed metabolites were screened,including 75 up-regulated metabolites and 38 down-regulated metabolites.The potted water dropwort of nutrient solution and soil of flavonoid content were 3.13 mg/g FW,2.28 mg/g FW,respectively.Metabonomic analysis found that the number of flavonoids and flavonoids differential metabolites are the most,a total of 104 flavonoids were detected,accounting for 21.4%of the total metabolites,23 different metabolites of flavonoids,accounting for 20.3%of the differential metabolites.Among them,14 were up-regulated,9 were down-regulated,and the overall performance was up-regulated,which was consistent with the absolute content measured.The potted water dropwort of nutrient solution and soil of VC content were 32.71 μg/g FW,36.26 μg/g FW,respectively.The metabolomic analysis showed that VC was down-regulated,which was consistent with the absolute content measured.It is proved that nutrient potted water dropwort is better than soil culture on the whole.