Drought resistance of Angelica dahurica during seedling stage under polyethylene glycol (PEG-6000)-simulated drought stress / 中国中药杂志

<p><b>OBJECTIVE</b>To study the optimum conditions of simulated drought stress, and screen the indexes of drought resistance and comprehensively assess the drought resistance of the Angelica dahurica resources during seedling stage.</p><p><b>METHOD</b>Investigations were carried out on the changes of height, root length, root-shoot ration, contents of soluble sugar, proline and malondialdehyde under polyethylene glycol (PEG-6000)-simulated drought stress. A comprehensive evaluation on the drought resistance of different (varietal) species of A. dahurica during seedling stage was applied by using the method of subordinate function. And the drought resistance indexes were selected out by applying the method of grey correlative degree analysis.</p><p><b>RESULT</b>Drought stress of 9 days with 20% PEG was the optimum condition for the simulation of drought stress. The results showed that the drought resistant capability decreased in the order as follows, A. dahurica from Sichuan province, A. dahurica from Henan province, A. dahurica from Hebei province and A. dahurica from Zhejiang province. And the order of correlative degree of drought resistance and indexes was: soluble sugar > root length > proline > root-shoot ration > total content of chlorophyll > chlorophyll b > chlorophyll a > height > malondialdehyde.</p><p><b>CONCLUSION</b>Osmotic adjustment substance and the indexes related to the root have more influence on the drought resistance of A. dahurica during seedling stage. A. dahurica from Sichuan province shows the highest drought resistance during seedling stage.</p>

Dynamic research of growth, N, P, K and active ingredients in Angelica dahurica var. formosana from Sichuan province / 中国中药杂志

<p><b>OBJECTIVE</b>To study the absorption and transformation of N, P, K and plant growth as well as the accumulation of active ingredients in Angelica dahurica var. formosana from Sichuan province and provide basis for rational fertilization.</p><p><b>METHOD</b>Samples were collected in different growth phrases, and correlative morphological indexes, the contents and accumulations of N, P, K and active ingredients were determined.</p><p><b>RESULT</b>The vegetative growth period of A. dahurica var. formosana sowed in autumn could be preliminarily divided into three phases: seedling period, aerial-part peak growth period and root peak growth period. With the development, the plant height and aerial part dry weight increased at the earlier stage, and then decreased. But the root length, root diameter, and root dry weight increased. The absorptive capacity of N, P and K varied among different developing stages. In general, the absorptive capacity of N and K was the higher than that of P. The order of total nutrition accumulation was N > P > K, the accumulation of N, P and K in aerial part decreased gradually during the growth period, while the accumulation of N, P and K in root increased gradually. The concentration of imperatorin and isoimperatorin showed decreasing-increasing-decreasing-increasing trend, while the accumulation of them increased gradually. And the correlation analysis results showed that the accumulation of P and K in aerial part had positive correlation with the concentration of imperatorin in root, the accumulation of N, P and K in root had positive correlation with the concentration of isoimperatorin in root.</p><p><b>CONCLUSION</b>From late April, A. dahurica var. formosana from Sichuan province entered root peak growth period and the accumulation of N, P, K, imperatorin and isoimperatorin in root increased rapidly. So the balanced application of fertilizer should be considered.</p>