Objective

2

To clarify the accumulation and distribution characteristics of dry matter and mineral elements in

Artemisia argyi

var.

argyi

cv.

Qiai

， and to provide technical support for the high yield of and efficient utilization of nutrients in this medicinal species.

Method

2

Two cultivars of

this species， Qiqing 1 and Qihuang 1 were selected， and the composition of dry matter in different organs， the content， accumulation， and distribution of mineral elements in each organ of the two cultivars， and the dynamic changes of volatile oil content and index components eucalyptol and borneol in

leaves of the two cultivars were monitored at different growth stages.

Result

2

The period from February to March marked the early growth stage of Qiai， and the dry matter was mainly distributed in the leaves. It accelerated the growth in April， and the period from April to mid-June witnessed the vigorous vegetative growth of Qiai， during which the dry matter was mainly found in the stems and leaves. It began the

reproductive growth from late June and the dry matter was mainly distributed in the stems. In the flowering stage in August， no dry matter accumulation occurred. As for the volatile oil， the content was high （

>

1.10%） at the vigorous vegetative growth stage and peaked on June 14 （1.33% in Qiqing 1， and 1.23% in Qihuang 1）. The relative mass fraction of eucalyptol was the maximum at the vegetative growth stage （8.67% in Qiqing 1， and 13.07% in Qihuang 1）. The relative mass fraction of borneol peaked at the early growth stage （2.63% in Qiqing 1， and 5.94% in Qihuang 1）. The content of nitrogen， phosphorus， potassium， and zinc in leaves was in significantly positive correlation with the content of volatile oil and the relative content of eucalyptol and borneol. The content of macroelements nitrogen， phosphorus， potassium， and calcium and trace elements iron and zinc peaked at the early growth stage， and the content was the highest in stem and leaf. The content of macroelement magnesium and trace elements manganese and copper was the highest at vegetative growth stage when the content of other elements decreased and the nutrients were gradually transferred to the buds， flowers and other organs. In the whole growth period， the distribution of potassium， calcium， and zinc was in the order of leaf

>

stem

>

root， and the distribution of nitrogen， phosphorus， copper， magnesium， and manganese followed the order of leaf

>

root

>

stem. The distribution of iron was in the order of root

>

leaf

>

stem. There was a significantly positive correlation between the total amount of dry matter and the absorption of nutrients in 'Qiai'. The absorption of macroelements by Qiai was in the order of potassium

>

nitrogen

>

calcium

>

phosphorus

>

magnesium， and the ratio of absorbed elements was about 2.66∶2.51∶0.6∶0.11∶0.04. The absorption of trace elements followed the order of manganese

>

iron

>

zinc

>

copper， and the ratio of absorbed elements was about 0.25∶0.17∶0.05∶0.04. In terms of the production of medicinal materials， 'Qiai'

needed about 4.11 kg potassium， 3.58 kg nitrogen， 0.91 kg phosphorus， 0.18 kg calcium， 0.06 kg magnesium， about 6.64 g manganese， 2.56 g iron， 1.30 g zinc， and 0.92 g copper to produce 100 kg medicinal materials.

Conclusion

2

Enough organic fertilizer and phosphorus and potassium fertilizers should be applied as base fertilizers for Qiai. The vegetative growth stage （April-June） marks the high accumulation of dry matter and large demand of nutrients， during which topdressing should be conducted timely and early， especially nitrogen fertilizer， and appropriate amount of micro-element fertilizer should be added. Qiai needs a large amount of calcium and magnesium fertilizers from the mid-vegetative growth stage， and they should be applied in time in the late stage to ensure the vegetative growth of the plants for seeds and the quality of the medicinal material of Qiai.