Effects of different K fertilizer and water level on growth and physiological characteristics of Isatis indigotica / 中国中药杂志

The experiment included three potassium levels (K0 0 g x kg(-1), K1 0.33 g x kg(-1), K2 0.67 g x kg(-1)) and two water gradients (well watered and drought stress), then measured growth indicators, SOD, POD, CAT activities and concents of osmotic regulation substances. To explore the effects of K fertilizer and water on growth and physiological characteristics of Isatis indigotica, providing reference for improving drought resistance of I. indigotica. The result showed drought stress inhibited the growth and decreased the biomass of I. indigotica but K fertilizer can alleviate the drought stress. Compared with K0 treatment, K1, K2 treatment increased the biomass of overground part of by 89. 13% ,60. 87% under drought stress. The corresponding increase in soluble sugar content was 16.67%, 5.00%, and in proline content was 42.41%, 65.62%, respectively. SOD,POD and CAT activities was significantly improved in K1, K2 treatment in comparison with K0 treatment under drought stress, but soluble protein content significantly reduced. The conclusion is that appropriate amount of K fertilizer can increase the activities of antioxidase and the content of osmoregulation substance under drought stress, and improve drought resistance of I. indigotica.

Effects of various planting densities on dynamic growth rhythm and root yield of Isatis indigotica / 中国中药杂志

<p><b>OBJECTIVE</b>To study the effects of various planting densities on dynamic growth and root yield of Isatis indigotica.</p><p><b>METHOD</b>The planting samples were collected to measure the growth period of each organ.</p><p><b>RESULT AND CONCLUSION</b>Under different planting densities, both main root length and breadth exhibited a trend of "fast-slow" by stages. However, the number of individual plant leaves were showed a trend of "slow-fast" on growth period. Meanwhile, the leaf length and breadth were exhibited a trend of "increase-decrease". The increase of dry leaf, dry root and whole plant dry matter was faster during the period of 65-76 days after seeding. The differences of root and leaf yields under various densities were significant. Planting densities has a great effect on yield of root. It must be shown that there was a positive development between the individual plant and colony. According to the dry matter of root and leaf, treatment B (i.e., 7 cm x 25 cm) was good choice.</p>