RESUMO
Objective: To study the effects of the applied amounts and their ratios of nitrogen (N), phosphorus (P), and potassium (K) on the yield and active ingredients of Angelica dahurica var. formosana from Sichuan Province. Methods: The field tests on N, P, and K ratios of A. dahurica var. formosana from Sichuan Province were carried out by using orthogonal combination design, the yield was weighted, and the imperatorin and isoimperatorin contents in its roots were determined by HPLC method. Results: The yield and the quality of A. dahurica var. formosana from Sichuan Province were extremely affected by different N, P, and K ratios. The yield was increased with N, P, and K, but for imperatorin and isoimperatorin content, the influence of different N, P, and K ratios is very different. The imperatorin content was increased with the moderate increase of N and P under the lower level of K (K2O 120 kg/hm2). The isoimperatorin content was increased with the moderate supplies of N and P ratios under the high level of K (K2O 240 kg/hm2). Whatever the ratios of P and K, the imperatorin content and isoimperatorin content are lower than that in the control treatment under the high level of N (195 kg/hm2). The orthogonal analysis of variance results also showed that the effects of N, P, and K on the yield reached extremely significant. The sequence of them was P > N > K.. The influence of N, P, and K on imperatorin all reached extremely significantly different level (P < 0.01). Among them, the effect of P and K was higher than that of N. But only N had significant influence on the contents of isoimperatorin (P < 0.05). The adapted combined application program was N 150 kg/hm2, P 2O5 225 kg/hm2, and K2O 120 kg/hm2, namely the ratio of N- P2O- K2O was 1.3:1.9:1, by which the highest yield and imperatorin content were obtained. There were significant difference compared with the control and its isoimperatorin content was the highest as well. Conclusion: The above ratios of N, P, and K could improve the yield and quality of A. dahurica var. formosana from Sichuan Province as well as the content of imperatorin and isoimperatorin.
RESUMO
Objective The absorption and distribution of nitrogen(N),phosphorus(P),and potassium(K) of Hedyotis diffusa was studied in field tests.Methods Through regular sampling,dry matter accumulation was studied,the contents of N,P,and K were analyzed by conventional methods.Results The uptake amount of N,P,and K by H.diffusa was lower at seedling stage,but increased rapidly at branching,blossoming,and fruiting stages,and the uptake amount of N and P decreased and K was negatively absorbed at mature stage.The uptake amount of N by H.diffusa was the highest,following was K2O,while P2O5 was the lowest.In the growing season of H.diffusa,the ratio of N,P2O5,and K2O was 1.00:0.14:0.54.N Mainly distributed in leaf at seedling,branching,and blossoming stages,while P2O5 and K2O mainly distributed in stem.The mineral nutrition mostly distributed in stem,flowers,and fruits at fruiting and mature stages,N and P2O5 mostly distributed in flowers and fruits,but K2O mainly accumulated in stem.Conclusion A little fertilizer should be applied at seedling stage,oppositly the use amount of fertilizer should be increased at branching,blossoming,and fruiting stages,particularly P and K at fruiting stage.
