Effects of Different Potassium Doses on Growth Rates and Micronutrients of Drought-Sensitive Beans

Abstract

When plants are exposed to abiotic stress, such as drought, their growth slows down and, in extreme condition, the plants might even begin to dry out, which causes great economic losses for the producers. One of the most important ways to save plants with less damage in stress environments, such as drought, is to fertilize them with potassium fertilizers because the plants with sufficient potassium amounts increase their tolerance to drought stress. This study aimed to determine the effects of potassium doses in order to decrease yield and quality losses due to drought stress during bean production. The cv. Zulbiye, a drought susceptible cultivar, and the bean genotype V71, a drought susceptible bean genotype, were chosen from previous studies. The bean seeds of these varieties were sown into 2 liter pots filled with perlite. Four doses of potassium (K) were applied as 0 K mg kg-1 (control), 500 mg kg-1 K, 1000 mg kg-1 K, and 2000 mg kg-1 K, in a completely randomized factorial experimental design with four replications, each having 4 pots. The seedlings were supplied with Hoagland solution and kept in a growth chamber with day temp. of 22-25??C and night temperatures of 17-19??C. Irrigation was completely stopped in the 20-day-old seedlings in drought stress treatment for 12 days, while the control seedlings were irrigated regularly. On the 20th day of the drought stress, the study was terminated, and the growth rate and some microelement contents (Cu, Mn, Zn and Fe) were determined. While there was a decrease in the growth rate and the amount of micronutrients in the plants in the group exposed to drought, it was observed that the negative effect of drought decreased and the growth rate and the amount of micronutrients started to increase in the plants to which potassium doses had been applied. It was also noticed that drought stress symptoms were decreased especially after the application of the doses of 1000 and 2000 mg kg-1 K.