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The ability to finish livestock on pasture over the summer–autumn period could improve the profitability of red meat enterprises in drought‐prone temperate regions. In south‐eastern Australia, traditional perennial options are limited by poor warm‐season performance (phalaris, Phalaris aquaticaL.) and widespread environmental constraints (lucerne, Medicago sativaL.). We aimed to identify perennial species suitable for summer–autumn finishing. We tested pure swards of summer‐active perennial grasses and herbs (20 cultivars across 14 species) in replicated small‐plot experiments at two sites on the Southern Tablelands of New South Wales, Australia. We assessed early persistence, productivity and warm‐season nutritive characteristics over 2–3 years. Lucerne and chicory (Cichorium intybusL.) persisted well through drought and produced herbage of high quantity and quality through summer–autumn. Digit grass (Digitaria erianthaSteud.) was highly persistent and productive but nutritive values were generally poor. Cocksfoot (Dactylis glomerataL.), tall fescue (Festuca arundinaceaSchreb.), perennial ryegrass (Lolium perenneL.), prairie grass (Bromus willdenowiiKunth.) and plantain (Plantago lanceolataL.) were productive but less persistent through drought, while nutritive values were sometimes inadequate. Chicory is a good alternative to lucerne, given its excellent summer–autumn performance, ability to survive droughts and superior acid soil tolerance. If appropriate management resolves issues with persistence and nutritive value, several of the other species could also be used to close the warm‐season feed gap in drought‐prone temperate environments. Pasture quality and quantity limit summer–autumn livestock production in drought‐prone temperate environments. We evaluated summer‐active perennial grasses and herbs over the warm season in south‐eastern Australia. Lucerne and chicory consistently showed high persistence, productivity and nutritive value. Digit grass, cocksfoot, tall fescue, perennial ryegrass, prairie grass and plantain also showed potential.

Context Improving the stability of legumes in grasslands in the face of variable seasonal conditions is key to mitigating risks posed by drought. Aims We assessed the persistence of a range of legume species and cultivars in order to inform legume choice for pasture improvement and identify priority species for further development. Methods Twenty field experiments in four series were conducted at sites with contrasting seasonal and soil characteristics in the ‘high-rainfall’ (560–920mm long-term average) Tablelands and Monaro regions of New South Wales, Australia. Legumes were grown as pure swards and assessed periodically for seedling density, plant frequency and dry matter for up to 5years. Key results Legume dry matter production was positively correlated with plant frequency. However, most legumes persisted poorly at most sites, particularly on soils of lower fertility. Subterranean clover (Trifolium subterraneum ) cv. Goulburn was the best performing cultivar of that species across sites on the Southern Tablelands and Monaro. Yellow serradella (Ornithopus compressus ) cvv. Avila and Yellotas showed promising persistence, particularly under drought conditions. White clover (T. repens ) was the most broadly adapted of the perennial legumes across a range of soils, but persistence was still inadequate at many sites. Lucerne (Medicago sativa ) was approximately twice as productive as the next-most productive species when soil conditions suited its growth, but it failed to persist on acidic, low-fertility soils. Conclusions Serradella species (yellow and French, O. sativus ) and white clover, in conjunction with subterranean clover, offer the best near-term prospects for diversifying legume productivity and resilience under variable seasonal conditions in tableland environments. Implications An increased focus on phenology and seed characteristics is suggested to improve the persistence of annual and facultative perennial legume species in grasslands. Serradella and white clover are identified as the highest priorities for cultivar development for tableland environments of south-eastern Australia.

Context High-quality, summer-active pastures could improve meat production in south-eastern Australia by facilitating livestock finishing over summer, with legumes critical for enhancing the nutritive value of pasture mixes. Available legumes vary in their ability to withstand moisture stress and grazing. Aims We aimed to identify legumes suitable for a summer–autumn finishing system. Methods We tested pure swards of 12 cultivars across eight legume species in replicated small-plot experiments at Goulburn and Bombala, New South Wales, assessing productivity, persistence and warm-season nutritive characteristics over 2–3years. Key results Lucerne (Medicago sativa ) was clearly the most productive species during summer and outperformed the clovers (Trifolium spp.) in terms of persistence and productivity throughout most of the experimental period at both sites, except during autumn 2021 after high rainfall in March. Caucasian clover (T. ambiguum ) was also highly persistent at both sites. Talish clover (T. tumens ) and strawberry clover (T. fragiferum ) were more persistent than white clover (T. repens ) and red clover (T. pratense ). White clover recovered strongly under high rainfall after drought, whereas red clover established rapidly but showed less capacity for post-drought recovery. Hybrid Caucasian×white clover was the least productive legume. Alternative clover species sometimes had slightly lower values of nutritive characteristics than white clover; red clover sometimes had distinctly lower values. Conclusions Lucerne performed best but several clovers were also productive, persistent and of high nutritive value over the summer–autumn period. Implications Talish, Caucasian and strawberry clovers warrant further investigation for inclusion in summer-active pastures in south-eastern Australia.

Phalaris aquatica L. (phalaris) is a cool-season perennial grass originating from the Mediterranean Basin, north-west Africa and Middle Eastern regions that is used for livestock agriculture mainly in temperate areas with dry summers. It has been the subject of breeding programs in Australia, South America, New Zealand and the USA. Increased knowledge of relationships between wild and cultivated germplasm through use of molecular markers has the potential to facilitate future breeding gains. For this purpose, we conducted an analysis of P. aquatica by using 3905 polymorphic DArTseq SNP markers. Genetic diversity as measured by expected heterozygosity was similar for wild (HE = 0.14; n = 57) and cultivated (HE = 0.13; n = 37) accessions. Diversity in wild germplasm was generally continuous in nature, largely related to geographical location, with a division at the broadest scale into eastern and western clades, with more admixture in the western than the eastern clade. Structure analysis of wild germplasm indicated six subpopulations consistent with country of origin, with some admixture among subpopulations likely resulting from natural and human influences. There were nine subpopulations among wild and cultivated accessions combined. This population structure should be considered if genomic selection is applied in P. aquatica. Analysis of molecular variance indicated that 71% of the genetic variation occurred within subpopulations and 29% among subpopulations. Genetic distances were low among cultivated germplasm from most countries except the USA, which was more distinct. Evaluation of material from the US pool by breeding programs in other countries, and additional material from the less utilised eastern clade, may be worthwhile.

Germplasm of the perennial pasture grass Phalaris aquatica L., from Sardinia, Italy, is a potentially valuable source for grass breeders owing to climatic similarities to regions where P. aquatica is used, a relatively high incidence of acidic soils, and exposure to prolonged grazing pressure. At field sites in south-eastern Australia, Sardinian accessions were compared as spaced plants and drill-rows with accessions from southern Europe and north-western Africa and with commercial cultivars. They were also evaluated in grazed swards at three sites over 4 years under conditions that challenge persistence, including heavy grazing pressure, acid soils and drought. Morphologically, the accessions were comparatively dense, fine and short, with similarities to southern European accessions and cultivars of the cv. Australian type. However, they were earlier heading and more summer-dormant, particularly those from southern Sardinia. In drill-rows, Sardinian accessions were later heading and less productive in winter than accessions from Morocco. In swards, Sardinian accessions had lower seedling vigour and winter growth potential than modern winter-active cultivars. However, they were dense and persistent under high grazing pressure, and some accessions survived better than all cultivars on an acid, low-fertility soil. Developing cultivars that are superior to the cv. Australian type with acceptable seed production and alkaloid levels presents a challenge to breeders. However Sardinian germplasm offers a range of maturity times combined with higher levels of summer dormancy and a grazing-tolerant morphology, attributes that may expand the area of adaptation of the species into the hotter and more drought-prone margin.

In recent decades several pasture legumes have been available in southern Australia as potential alternatives to the most widely used annual pasture legume Trifolium subterraneum. Little is known about their soil phosphorus (P) requirements, but controlled environment experiments indicate that at least some may differ in their P fertiliser requirements. In this study, pasture legume varieties, including T. subterraneum as the reference species, were grown at up to four sites in any one year over a 3-year period (in total, seven site × year experiments) to measure herbage growth responses in spring to increased soil P availability. A critical soil test P concentration (corresponding to 95% maximum yield) was estimated for 15 legumes and two pasture grasses. The critical soil P requirements of most of the legumes did not differ consistently from that of T. subterraneum, indicating their soil fertility management should follow the current soil test P guidelines for temperate Australian pastures. However, the critical P requirement of Medicago sativa was higher than that of T. subterraneum, but remains ill-defined because extractable soil P concentrations in these experiments were often not high enough to permit a critical P estimate. Three forage crop legumes (Trifolium incarnatum, Trifolium purpureum, Trifolium vesiculosum) and two pasture legumes (Ornithopus compressus, Ornithopus sativus) had lower critical soil test P concentrations. It may be feasible to manage pastures based on these species to a lower soil test P benchmark without compromising yield.

The adaptation of introduced perennial grasses in southern Australia expanded with the discovery of the Mediterranean grass phalaris (Phalaris aquaticaL.) as a valuable pasture species, and the introduction of Mediterranean ecotypes of orchardgrass (Dactylis glomerataL.), and tall fescue [Lolium arundinaceum(Schreb.) Darbysh.] displaying summer dormancy. In contrast, native grasses of agricultural importance appear to have little or no endogenous summer dormancy. A brief history of cultivar development from Mediterranean germplasm is presented. Recent developments include cultivars based on summer‐dormant subsp. hispanicaorchardgrass and the release of Mediterranean‐type cultivars of tall fescue. Phalaris depends on a deep root system and summer dormancy for its summer survival. Cultivars based on more summer‐dormant Moroccan ecotypes have been developed for drier environments. Work to improve phalaris for hotter, summer‐dominant rainfall areas is being extended to enhance the range of perennials for the cropping zone. In addition to ecotype evaluation, breeders should employ recurrent selection in cultivars and populations such as those developed recently for low‐ to medium‐rainfall areas in orchardgrass and tall fescue.