Influence of Silica on Growth, Quality, and Wear Tolerance of Seashore Paspalum

L.E. Trenholm, R.R. Duncan, R.N. Carrow, and G.H. Snyder

Published in Journal of Plant Nutrition 24:1-5, 2001

Abstract

Wear is a predominant stress affecting growth of turfgrass. Wear tolerance may be increased by management practices that increase shoot density or leaf turgor, or that influence the amount of cell wall constituents. 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 Si would enhance turfgrass wear tolerance, growth, and quality. This research was conducted in two consecutive field trials during 1998 on two seashore paspalum (Paspalum vaginatum Swartz.) greens-quality ecotypes established on a native Appling (Typic Kanhapludult) soil at the University of Georgia Experiment Station in Griffin, GA. Silica was applied as potassium 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 non-wear 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 by either K alone or by the high rate of Si and K. Turf growth was not affected by fertility treatments. Cell wall constituents differed due to treatments only in the first study. No correlative effect was noted between cell wall components and qualitative scores. Higher tissue K concentration was associated with lower total cell wall (TCW) content, a characteristic related to enhanced wear tolerance of paspalum. Increased turf quality scores resulting from K application may be associated with increased turgor pressure. 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 TCW.