%0 Journal Article %A ZHAO Hongmei %A DENG Sufang %A YANG Yanjun %A JI Aiqing %A LI Hongyan %T Effect of Drought Stress on Anatomical Structure and Physiological Characteristics of Quinoa Seedlings %D 2021 %R 10.11869/j.issn.100-8551.2021.06.1476 %J Journal of Nuclear Agricultural Sciences %P 1476-1483 %V 35 %N 6 %X In order to explore the responses of different tissues of quinoa seedlings to drought stress, a pot-planting study was conducted with different field capacity (100%, 50%, 25%) and different treatment times (0, 48, 96h). Then the anatomical structures were observed, and the proline content, the activities of pyrroline-5-carboxylate synthetase (P5CS), proline dehydrogenase (PDH), peroxidase (POD), superoxide dismutase (SOD) and the catalase (CAT) were analyzed in the root, stem, and leaf tissues of quinoa seedlings. The results showed that the quinoa root diameter and epidermal thickness increased as the field capacity decreased and the treatment time extended with a maximum increase of 9.1% and 64.9%, respectively. The values of various indicators of the stem tissue exhibited a gradual decrease with the medullary cavity diameter decreasing by a maximum of 55.6%. The values of various parameters of the leaf tissue also reached the minimum under 25% field capacity in 96h. The proline content and the P5CS enzyme activity in the three tissues displayed a gradually increasing trend. The accumulation of proline in the leaves was higher than that in the stems and roots. The PDH enzyme activity in the leaves and stems gradually decreased, whereas it increased gradually in the roots. The antioxidant enzyme activity in all three tissues were different in different treatments. The enzyme activity in the leaves and stems reached the highest at 50% field capacity in 96 h, and the activity of the three enzymes in the roots still maintained higher activity at 25% field capacity in 96 h. In short, quinoa seedlings can adapt to a certain degree of drought by thickening the roots under drought stress. The drought resistance is improved by increasing proline content, P5CS enzyme activity and antioxidant enzyme activity in the seedlings. The morphology and physiological responses of the roots under drought are different from those of the leaves and stems. This study provides some basic information for further investigation and utilization of the mechanism of quinoa's stress resistance. %U https://www.hnxb.org.cn/EN/10.11869/j.issn.100-8551.2021.06.1476