INFLUENCE OF SILICA ON GROWTH, QUALITY, AND WEAR TOLERANCE OF SEASHORE PASPALUM

Abstract

Wear is a predominant stress affecting growth of turfgrass. Silica, which is deposited in epidermal cells of leaf blades, may potentially increase rigidity of a turfgrass stand. This research was undertaken to determine if application of silicon (Si) would enhance turfgrass wear tolerance, growth, and quality. This research was conducted during two consecutive field trials in 1998 on two greens-quality ecotypes established on a native Applying (Typic Kanhapludult) soil at the University of Georgia Experiment Station in Griffin, GA. Silica was applied to two ecotypes of seashore paspalum (Paspalum vaginatum Swartz.) as potassium (K) silicate at two foliar rates (1.1 and 2.2 kg Si ha⁻¹) and as a soil drench rate of 22.4 kg Si ha⁻¹. Potassium chloride, which added K at the amount in the drench treatment (15.6 kg K ha⁻¹), was also applied as a K check. Best turf quality responses on nonwear plots resulted from highest rates of Si application as well as from the K only treatment. A positive association was found between leaf tissue K concentration and turf quality scores, while increasing Si concentration reduced quality scores. Wear tolerance was enhanced either by K alone or by the high rate of Si and K. Turf growth was not affected by fertility treatments. Enhanced wear tolerance, due to application of either K alone or Si and K, reduced wear injury from 35% to 14% (K) or 20% (Si and K) averaged across both studies. This may be attributed to increased leaf turgor pressure or reduced total cell wall (TCW).

ACKNOWLEDGMENTS

The authors gratefully acknowledge funding from the United States Golf Association, the Golf Course Superintendents Association of America, the Georgia Turfgrass Foundation Trust, Turfgrass Producers International, and the Potash and Phosphate Institute.