Influence of Nitrogen and Irrigation on Carbohydrate Reserves of Buffalograss

Abstract

Five rates (0, 30, 60, 90, and 120 kg of N/ha) of nitrogen fertilizer were applied in April, 1971, to a deep hardland range site where buffalograss (Buchloe dactyloides Nutt.) predominated. The influence of these nitrogen applications on the carbohydrate reserve (TAC) concentration of irrigated and nonirrigated buffalograss roots and crowns was evaluated. In 1971 the TAC reserve concentration of the storage tissues varied inversely with rate of nitrogen application until the past ripe phenological stage. After this date, TAC's accumulated more rapidly in the heavier N treatments. In 1972, insignificantly more TAC were found in the control and 30 kg N/ha treatments at the hard seed stage. On all sampling dates buffalograss crowns contained more reserve carbohydrates than did the roots. Similarly, stolons contained 19% more TAC than did the crowns. Water applications reduced the carbohydrate reserves of this grass from 15 to 36%. Irrigation increased female spikelet yield by 44 kg/ha while stolon yield was similar regardless of water regime.