磷肥施用量对蕲艾生长和品质的影响

Effects of phosphorus application rate on the growth and quality of Artemisia argyi

【目的】探究不同磷肥施用量对蕲艾(Artemisia argyi)生长和品质的影响,为实现蕲艾的高产优质栽培提供科学施磷依据。【方法】蕲艾田间试验在湖北蕲春基地进行,供试材料2018年为新植蕲艾,2019年为二年生蕲艾。在施用氮肥(N)120 kg/hm^(2)、钾肥(K2O)120 kg/hm^(2)基础上,设置5个磷肥(P_(2)O_(5))用量:0、60、120、180、240 kg/hm^(2),依次表示为P_(0)、P_(60)、P_(120)、P_(180)、P_(240)处理。调查蕲艾农艺性状、叶片产量,分析艾叶中矿质元素积累量、出绒率、总挥发油及挥发性成分含量、黄酮和酚酸类成分含量。【结果】施用磷肥显著增加了蕲艾叶片产量,但2018年的4个施磷处理的艾叶产量没有显著差异,2019年的P_(60)处理显著低于P_(120)、P_(180)、P_(240)处理,P_(120)、P_(180)、P_(240)处理间没有显著差异。采用曲线拟合计算,2018和2019年蕲艾叶片产量达到最高的磷肥施用量分别为166.5和157.7 kg/hm^(2)。施磷提高了艾叶对N、P、Ca的吸收,降低了对Cu的吸收,对艾叶Mg和Zn元素含量无明显影响。随磷肥施用量的增加,磷肥叶片利用率、磷肥农学效率呈先增加后降低的趋势,磷肥偏生产力呈逐渐降低的趋势。新植艾叶和两年生艾叶出绒率最高的处理分别为P_(180)和P_(120),分别比P_(0)提高了21.0%和12.3%,经曲线拟合计算,最大出绒率对应的磷肥施用量分别为140.2和165.0 kg/hm^(2)。施入磷肥能显著提高蕲艾叶片中总挥发油、桉油精、8种黄酮和酚酸类成分含量,但α-侧柏酮和樟脑含量随磷肥施用量的增加呈降低趋势。对艾叶出绒率、总挥发油及4种挥发性成分含量、8种黄酮和酚酸类成分含量等14个艾叶品质指标进行主成分分析,新生艾叶提取的前3个主成分的累计贡献率为98.9%,二年生艾叶提取的前2个主成分的累积贡献率为92.6%。对艾叶综合品质得分进行排名,由高到低的顺序2018年为P_(120)>P_(180)>P_(240)>P_(60)>P_(0),2019年为P_(180)>P_(120)>P_(240)>P_(60)>P_(0)。【结论】在本试验条件下,施用磷肥可显著影响蕲艾的生长、叶片产量和品质,适宜的磷肥用量可显著提高蕲艾叶片的出绒率以及艾叶中挥发性成分的比例。磷肥施用量分别为P_(2)O_(5)180、120 kg/hm^(2)时新植蕲艾和2年生蕲艾叶的出绒率最高,综合品质得分排名靠前,且磷肥叶片利用率和磷肥农学效率都较高。

【Objective】Chinese mugwort(Artemisia argyi)is an important herb resource,and meeting the high demand for it heavily relies on establishing an artificial plantation.In this paper,we studied the effects of phosphorous(P)fertilizer application rate on the growth and quality of mugwort(A.argyi).【Methods】Field experiments were conducted in the main production base of Chinese mugwort(A.argyi)in Qichun,Hubei Province.Newly transplanted seedlings and regenerated seedlings of mugwort were tested in 2018 and 2019,respectively.The P_(2)O_(5) rate treatments included 0,60,120,180,and 240 kg/hm^(2)(i.e.,P_(0),P_(60),P_(120),P_(180) and P_(240),respectively).The agronomic characteristics,leaf yield and the output rate of moxa were measured.Mineral contents,total volatile oil,volatile components,flavonoids and phenolic acids in A.argyi leaves were determined.【Results】The application of P fertilizer significantly increased the leaf yield of A.argyi but not the agronomic characteristics.There was no significant difference in the leaf yield of the four P rate treatments in 2018,and P_(120),P_(180) and P_(240) treatments recorded a similar leaf yield in 2019.According to the fitted curve,the highest leaf yield of A.argyi was recorded at P 166.5 kg/hm^(2) in 2018 and 157.7 kg/hm^(2) in 2019.P application increased the uptake of N,P and Ca,but not Mg and Zn,and decreased that of Cu.P application significantly increased the output rate of moxa.The highest moxa yield was obtained at P_(180) and P_(120) treatments in 2018 and 2019,which were 21.0%and 12.3%higher than that in P_(0) treatment.According to the fitted curve,the P rate promoting the highest output was P_(2)O_(5)140.2 kg/hm^(2) in 2018 and 165.0 kg/hm^(2) in 2019.Total volatile oil,eucalyptus oil,and 8 kinds of flavonoids and phenolic acids found in A.argyi leaves were significantly increased by applying P fertilizer.However,the contents ofα-thujone and camphor decreased with an increase in P fertilizer application.Principal component analysis was conducted on 14 quality indexes of A.argyi leaves under different P application rates in two years.Three principal components were extracted in the 2018 experiment,whose cumulative contribution rate was 98.9%,and two principal components were extracted in the 2019 experiment,whose cumulative contribution rate was 92.6%.The total score showed that the quality of A.argyi leaves treated with P_(120) and P_(180) treatments was higher than taht of other treatments,and the quality of A.argyi leaves treated with P_(0) treatment was the lowest.【Conclusions】The application rate of P fertilizer affect the growth,leaf yield and quality of mugwort(A.argyi.).Under the experimental condition in Qichun,a reasonable P fertilizer application rate could substantially increase the output of moxa and the ratio of components in the total volatile oil of mugwort.The highest leaf yield was recorded at P_(2)O_(5)180 kg/hm^(2) for newly transplanted mugwort and 120 kg/hm^(2) for regenerated mugwort.A high comprehensive score of mugwort corresponds to high P fertilizer use efficiency.