GROWTH AND ESTABLISHMENT OF Bouteloua gracilis (Kunth) Lag. ex Griffiths AND Eragrostis curvula var. conferta Stapf SEEDLINGS UNDER A SIMULATED RAINFALL REGIME

Abstract

The effect of a simulated-rain regime was evaluated on the development and seedling establishment of blue grama Bouteloua gracilis, and boer lovegrass (Eragrostis curvula var. conferta) under greenhouse conditions. A group of seedlings was maintained under waterings to field capacity while another group of seedlings was maintained under a simulated-rain regime; the regime was simulated from real climate records registered in a weather station located near the site where the seeds were collected. Every 3 d, the number of leaves, tillers, and seedling height was measured. 37 d after seedling establishment, root and tiller dry weights, and root to shoot ratios were determined. B. gracilis seedlings developed more tillers per seedling and higher heights under field capacity conditions than under the simulated-rain regime (P ≤ 0.05). Conversely, E. curvula seedlings grown under the simulated-rain regime developed more tillers and leaves than their counterparts grown under field capacity conditions, and than B. gracilis grown under both watering regimes. The two grasses showed a 90 % establishment under field capacity conditions, but in boer lovegrass grown under the simulated-rain regime this variable decreased 10 %. The evaluation scheme proposed in this work might be a reliable tool to analyze the establishment and development of grass seedlings growing under greenhouse conditions and water stress.