An evaluation of the production potential of six tropical grasses under grazing. 1. Yield and yield components, growth rates and phenology

Abstract

Fertilised pastures of 4 varieties of Setaria sphacelata (var. splendida and cvv. Nandi, Narok and Kazungula), pangola grass (Digitaria eriantha ssp. pentzii) and kikuyu grass (Pennisetum clandestinum cv. Whittet) were grazed rotationally over a 3-year period at Beerwah, south-eastern Queensland. Each variety was grazed on a 5-weekly rotation by 2 leaders for 7 days; a follower herd including 2 testers grazed the regrowth for 7 days. The numbers of followers were subjectively adjusted weekly, depending on feed available. The experiment was designed to provide adequate quantities of forage of maximum potential quality to the leaders throughout the year. There were large and frequently consistent differences between the grasses in yield and its various components, leafiness, leaf and forage density, rate of development of leaf dry matter, and time and intensity of flowering under the management system imposed. Of particular interest were the high leaf yield of Narok, high overall yield of Narok and var. splendida, low rate of development of leaf area index of pangola grass and kikuyu grass, and high forage density of kikuyu grass. These differences might be expected to have an effect on pasture quality, carrying capacity and optimal management strategy.

Selection of morphological traits to improve forage characteristics ofSetaria sphacelatagrown in Florida

“…Levels of production are comparable to those obtained in Australia under grazing, where 3510 to 4790 kg ha -1 (Jones & Evans 1989) and 3400 to 5280 kg ha -1 (Hacker & Evans 1992) were obtained for three and four cultivars of Table 3 Seed yield in four selected populations and one cultivar of Setaria sphacelata in 1999 in the wide-spacing experiment. Means followed by the same letter within each column do not differ significantly at P > 0.05, according to the Waller-Duncan multiple comparison procedure.…”

“…setaria, respectively. Leaf production varied from 690 to 3180 kg ha -1 (Table 4), a wider range than the range of 1340 to 1760 kg ha -1 obtained in Australia (Hacker & Evans 1992). HEAD 1, 'Splenda' and 'Fenwicks' had leaf:stem ratios less than 1.0.…”

“…However, higher leaf:stem ratios than the ones reported here were observed in a grazing trial in subtropical coastal lowlands of south-east Queensland. Four cultivars of setaria varied from 0.94 to 2.08 leaf:stem ratio, with a mean of 1.56 under rotational stocking (Hacker & Evans 1992).…”

Breeding and evaluation of Digitaria eriantha for improved spring yield and seed production

“…In comparison to the other grass cultivars with which it was compared, Advance was a little higher yielding in the cool season than Narok setaria and Whittet kikuyu grass, both of which are noted for their cool-season productivity (e .g . Hacker & Evans, 1992) . The comparatively high cutting height of 60 mm in the Grafton trials would have favoured the tall-growing digit grasses and so their apparent relative advantage over the stoloniferous kikuyu grass may be misleading.…”