Effect of Potassium on Quality of Guava

Abstract

Guava plants were grown in 50 liters pot with fine sand. The plants were treated with four different levels of potassium concentrations i.e. 600, 800, 1000 and 1200 meq/l. The guava plants were given about 1-2 liters of the nutrient solution every day. The experiment was conducted at Department of Horticulture, Faculty of Agriculture, Chiang Mai University during December 1998 to July 1999. The results showed that all treatments had no effect on the stem height, stem diameter and dry weight, but it was significant by affected canopy width and fruit growth. At 1200 meq/l fruit weight, fruit size, Tritrable Acid (TA) and Total Soluble Solids (TSS) of fruits were higher than other treatments, whereas the firmness of fruit and vitamin C content were not different. The concentration of potassium affected the accumulation of Mg in leaf. Guava leaves had more Mg content when low K concentration was applied. The Mg content decreased when the level of K supply was high. However the levels of N, P, K, Ca, chlorophyll-a and chlorophyll-b content were not different in all the treatments.