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Background: 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 aquatica L.) and widespread environmental constraints (lucerne, Medicago sativa L.). We aimed to identify perennial species suitable for summer–autumn finishing. Methods: 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. Results: Lucerne and chicory (Cichorium intybus L.) persisted well through drought and produced herbage of high quantity and quality through summer–autumn. Digit grass (Digitaria eriantha Steud.) was highly persistent and productive but nutritive values were generally poor. Cocksfoot (Dactylis glomerata L.), tall fescue (Festuca arundinacea Schreb.), perennial ryegrass (Lolium perenne L.), prairie grass (Bromus willdenowii Kunth.) and plantain (Plantago lanceolata L.) were productive but less persistent through drought, while nutritive values were sometimes inadequate. Conclusions: 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. [ABSTRACT FROM AUTHOR]

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 2–3 years. 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. Profitability of livestock production over summer–autumn in the temperate environment of south-eastern Australia could be improved by including legumes in pastures that are persistent, productive and of high nutritive value. Evaluation of a range of legume species and cultivars showed that lucerne remained the most reliably productive warm-season option where soil conditions support it. Talish, Caucasian and strawberry clovers were persistent and of high nutritive value, warranting further evaluation in special-purpose warm-season pastures. [ABSTRACT FROM AUTHOR]

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. Knowledge of genetic diversity is important for traditional and genomics-based breeding in the perennial pasture grass Phalaris aquatica. Use of molecular markers indicated the presence of nine groups among wild and cultivated germplasm, with close relationships among cultivars from most countries where P. aquatica is bred. Population structure should be considered for genomic breeding of P. aquatica and more testing of germplasm from less exploited germplasm groups may be worthwhile in future breeding. [ABSTRACT FROM AUTHOR]

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. Germplasm of Phalaris aquatica from Sardinia is a potentially valuable source of grass cultivars for livestock production in regions that experience dry summers. Accessions from Sardinia displayed lower seedling vigour and winter growth than modern cultivars but were denser and more persistent under high grazing pressure and had good spring production, and some accessions survived better on difficult soils. The germplasm displayed attributes that could help livestock industries facing multiple stresses in the future. [ABSTRACT FROM AUTHOR]

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. Extractable phosphorus concentrations of soil corresponding to near-maximum pasture legume growth can be used as benchmarks for soil phosphorus management in temperate grass–legume pastures. In this study, the soil phosphorus requirements of alternative pasture legumes used in southern Australia were assessed and compared with that of the widely used legume Trifolium subterraneum. The results indicate that published soil test phosphorus benchmarks for T. subterraneum are appropriate for many alternative legumes, but also demonstrate that some can be fertilised to lower benchmark concentrations without compromising yield. [ABSTRACT FROM AUTHOR]