Investigating the Adjustment of Soil Drought Stress with Potassium in Different Levels of Potash Fertilizers (Case Study: Zinnia)

One of the important issues in sustainable agricultural management is the proper yeid of the agricultural products under environmental stress conditions. Naturally, in the dry country of Iran, lack of moisture is one of the main challenges of agriculture. Proper plant nutrition can moderate the effects of drought stress. To investigate the effects of drought stress on plant yield, Zinnia was used as a test plant. For this purpose, the growth of Zinnia plant in response to drought stress at different levels of potassium fertilization was investigated in a factorial experiment based on a randomized completely block design with two factors. The first factor: Three periods of irrigation including 2 days, 4 days, one week and the second factor: Four levels of potassium fertilizer including: 1) Use of potash fertilizer as base, 2) Use of potash fertilizer as base and during the growth period, 3) Use of potassium fertilizer as a base and during the growth period + 2 times foliar spraying, 4) Using potash fertilizer as base and during the growth period + 4 times foliar spraying. The cultivation medium was used in a 2:1 ratio of soil and manure in each pot. After the end of the growth period, the vegetative indicators include fresh and dry weight of aerial organs (shoot), plant height, number of lateral branches, number of flowers, flower weight, length of the longest branch were measured. The highest growth indices were: Fresh and dry shoot weight in treatment 4 and 2 days irrigation equal 2.36 and 0.33 g, respectively; plant height in treatment 4 and 2 days irrigation; the number of lateral branches in treatment 4 and 2 days irrigation equal 8; and the length of the longest branch in treatment 4 and 2 days irrigation equal 9 cm. The growth conditions in the fertilizer treatments were better than the control and this shows that potassium has increased the resistance of the plant to drought stress.