Growth Responses of Bermudagrass to Different Levels of Nutrients in the Culture Medium

Abstract

Bermudagrass (Cynodon dactylon L.), cv. Arizona Common was studied in a greenhouse to evaluate its growth responses in terms of shoot and root lengths and shoot and root dry weights under different levels of nutrients. Plants were grown hydroponically under five levels of nutrients in the growth medium [Full Nutrients (FN), Half Nutrients (½N), Quarter Nutrients (1/4N), One Eighth Nutrients (1/8N), and One Sixteenth Nutrient (1/16N)], using Hoagland solution No. 1. Plant shoots (clippings) were harvested weekly, oven dried at 60 °C, and dry weights recorded. At each harvest, both shoot and root lengths were measured and recorded. At the last harvest, plant roots were also harvested, oven dried, and dry weights were determined and recorded. The results show that shoot length, shoot and root dry weights, shoot total-N contents and concentrations, and the % of canopy green cover significantly decreased at lower (1/8 & 1/16) nutrient levels. This reduction was more pronounced as growth period progressed. Root length was stimulated at lower (1/4, 1/8, and 1/16) nutrient levels of the culture solutions. The differences in shoot lengths and shoot and root dry weights were not significant among the Full, 1/2, and 1/4 nutrient levels of the culture solutions. The differences in shoot total-N content and concentrations were not significant among the Full, 1/2, and 1/4 nutrient levels. There was no difference in either shoot total-N contents or concentrations among the respective nutrient treatments at different harvests. The above results were observed for both cumulative as well as the weekly growth responses.