Perennial pastures for recharge control in temperate drought-prone environments. Part 1: productivity, persistence and herbage quality of key species

Abstract

Perennial-based pasture swards potentially offer land managers the capacity for recharge control in temperate cropping zone environments to satisfy the dual role of fostering increased agricultural productivity and reduced deep drainage. This study evaluated the productivity, persistence and herbage quality of lucerne (Medicago sativa L.), phalaris (Phalaris aquatica L.), chicory (Cichorium intybus L.), perennial veldt grass (Ehrhata calcycina Sm.), grazing brome (Bromus stamineus E. Desv.), plantain (Plantago lanceolata L.), Rhodes grass (Chloris gayana Kunth), tall fescue (Festuca arundinacea syn. Lolium arundinaceum Schreb. syn. Schedonorus phoenix (Scop.) Holub.) and cocksfoot (Dactylis glomerata L.) in two contrasting environments in the cropping zone of southern New South Wales (NSW), Australia. The performance of two cultivars with contrasting levels of summer activity of each of the latter two species was also assessed. Lucerne was the most productive species evaluated, producing 54Á85% more herbage than phalaris, the next most productive species. Lucerne was also the most persistent species with a higher basal frequency than all other species during the experimental period and, averaged across samplings, had the highest crude protein (22.3%) in the leaf and stem of any species. Chicory herbage had the highest dry matter digestibility (76.7%) and ash content (15.1%) and lowest neutral (35.4%) and acid detergent fibre contents (21.8%) compared with the other species. The more summer-dormant cultivars of cocksfoot (cv. Kasbah) and tall fescue (cv. Fraydo) were both found to be more persistent than their semi-summer-active counterparts (cvv. Currie and Demeter, respectively), demonstrating the importance of summer dormancy for the persistence of both species in these environments. Tall fescue cv. Fraydo was equally persistent yet produced only 42Á51% of the cumulative biomass of phalaris over 5 years, indicating that tall fescue is not a viable species in these drought-prone environments, nor were plantain and grazing brome due to their inferior productivity and persistence. The study highlighted the lack of viable perennial pasture options currently available in cropping zone environments of southern NSW other than lucerne, phalaris and the summer-dormant cultivar of cocksfoot, Kasbah. Chicory and perennial veldt grass, with further breeding and selection under Australian environmental conditions, could have the potential to be viable perennial pasture options for the cropping zone of southern NSW.

Future consequences and challenges for dairy cow production systems arising from climate change in Central Europe – a review

“…The botanical composition of grassland should include species that are able to withstand the changing conditions. Recent research has shown considerable differences in growth and digestibility among grass species under drought (Hayes et al, 2010). However, more research is necessary as to which species and genotypes are best suited for permanent grassland in Central Europe managed for high yielding dairy cows.…”

Modelling of lucerne (Medicago sativa L.) for livestock production in diverse environments

“…accounted for in the model -namely poor establishment (Li et al 2010) -have influenced the 621 production of the winter-active cultivar (SARDI 7). 622 623 An area of uncertainty concerns the growth, development and functioning of lucerne roots.…”

Perennial pastures for recharge control in temperate drought-prone environments. Part 2: soil drying capacity of key species

“…This was done by placing a 1 m 2 quadrat (divided into squares of 0.1 m)0.1 m) over the sampling area and counting the percentage of squares occupied or partially occupied by the base of a sown perennial plant. Further details on basal frequency of the treatments are given by Hayes et al (2010).…”

“…A residual of 500Á800 kg/ha of above-ground biomass remained on the plots following defoliation. Further details on herbage yields of various treatments are described by Hayes et al (2010).…”

“…Rarely has any pasture species been reported to exceed lucerne in its capacity to dry the soil profile, although occasionally an alternative species is reported to have achieved the same level of drying as lucerne. Despite the proven capacity of lucerne to dry the soil profile, Hayes et al (2010) argued for the need to identify viable alternative perennial pasture species in order to increase the sustainability of farming systems. Put simply, this argument is centred around: (i) the need for a variety of agronomic characteristics to satisfy various environmental and enterprise-dependent niches in agriculture; (ii) the need to reduce the vulnerability of existing farming systems to invasion from pests and diseases; (iii) the limited area over which one species, even one that is as broadly adapted and productive as lucerne, can feasibly be grown in a production enterprise.…”