A comparison of seventeen introductions of Paspalum species and naturalized P. dilatatum under cutting at Samford, south-eastern Queensland

Abstract

Seventeen introductions representing ten species of Paspalum were compared with naturalized P. dilatatum var. dilatatum in a randomized block experiment with four replications having split-plots which were cut at 6-, 8-, and 12-weekly intervals. The grasses were planted vegetatively at a uniform spacing 21 months before treatments commenced. Treatments were continued for two years, during which all plots received a mixed fertilizer application every six weeks totalling 8 cwt an acre urea, 4 cwt an acre superphosphate, and 2 cwt an acre potassium sulphate a year ; this was in addition to liberal fertilizer applications during the establishment period. Rainfall was supplemented with irrigation. The introduced grasses differed markedly in total annual yield of dry matter, persistence, seasonal growth rate, reaction to cutting frequency, frost susceptibility, and amount of weed invasion, and it is concluded that a number of them are potentially much superior to naturalized P. dilatatum as pasture grasses in south-east Queensland. The best grasses were P. yaguaronense (C.P.I. 11867), P. notatum var. saureae (C.P.I. 9073), P. notatum var. latiflorum (C.P.I. 11863), and P. plicatulum sens. lat. (C.P.I. 2741) ; these all produced annual yields at 6-weekly cutting of over 17,000 lb an acre dry matter and had a much better seasonal distribution of production than naturalized P. dilatatum. Six other grasses also appeared to be superior to naturalized P. dilatatum. They are P. dilatatum var. pauciciliatum (C.P.I. 11814, 11824, 11859), P. conspersum (C.P.I. 17651), P. urvillei (C.P.I. 11868), and P. plicatulum var. glabrum (C.P.I. 11826).