Water Use in Relation to Management of Blue Panicgrass (Panicum antidotale Retz.)

Abstract

Efficiency of water use was determined for blue panic-grass grown in the field. Management treatments were soil-moisture stress, clipping height, and maturity stage. Water-use efficiency was expressed as the number of units (kg) of water per unit (kg) of forage dry-weight produced. Blue panicgrass showed a relatively broad tolerance to high soil-moisture stress. Efficient use of water and root weight decreased when soil-moisture stress was increased, while dry-weight of forage was unchanged. The 30-cm clipping height, when the majority of seed heads emerged from the boot, was most efficient in water use; gave the highest production of forage; produced the highest percentage protein; and produced the most roots. Two noteworthy findings were: a) the most efficient use of water and the highest forage production were obtained from the same management; and b) the highest protein percentage and the highest forage production were obtained from this same management. This performance of blue panicgrass where highest production of forage, highest percentage of protein, and most efficient use of water is contrary to the performance of some crops, because these responses rarely occur for the same management.