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Context: Opportunity exists to expand serradella (Ornithopus spp.) use onto heavier, duplex soil types in permanent pasture environments of south-eastern Australia. This requires cultivars with appropriate flowering times and flowering-date stability (i.e. flowering at the same date in spring regardless of timing of the autumn break). Aim: This work examined evidence of variation in flowering date and flowering-date stability in the NSW southern tablelands for a widely-used French serradella (O. sativus) cv. Margurita. Methods: Seed (sourced from a commercial supplier) was sown 21 March 2019 (Canberra, ACT) and 231 individual plants were monitored for time to first flower. A subset of plants exhibiting 'early' or 'late' flowering were identified and their seeds collected. In 2020, seed from ~15 plants from each selection was sown in Canberra in late March and early May to represent an 'early' and a 'later' break of season (n = 3). Key results: In the early-sown treatment, 'early-flowering' selections typically reached the median date of first flower (50%-flowering) from mid- to late August, while 'late-flowering' selections reached 50%-flowering early- to mid-September. When sown later, the 'early-flowering' selections began flowering from mid- to late September, while the 'late-flowering' selections flowered mid-September to early October. The 'early' selections exhibited greater flowering-date instability than 'late' selections and flowered particularly early when sown early. This indicated diversity within cv. Margurita for flowering-time control (e.g. vernalisation and/or photoperiod requirements). Implications: Evaluating cultivars of serradellas for flowering date and flowering date stability in their target environment(s) is essential to ensure cultivars are suitably adapted to these environments. Serradellas (Ornithopus spp.) are a novel legume option for the permanent pasture environments of south-eastern Australia. This paper investigated evidence of variation in flowering time characteristics within a widely used cultivar of French serradella. We recommend that new cultivars of serradellas be evaluated for flowering time characteristics in their target environment(s) to assess whether the cultivars are suitably adapted to these environments. This is essential to maximise production, feeding value and facilitate effective grazing management. [ABSTRACT FROM AUTHOR]

Context: There is interest in using serradella (Ornithopus spp.) in permanent pastures of the high rainfall zone of south-eastern Australia. However, there is little information concerning levels of hardseededness or patterns of seed softening in these environments. Aim: This study quantified seed softening of serradella species in comparison with subterranean clover (Trifolium subterraneum L.) in the Southern Tablelands and Central Slopes districts of eastern Australia. Methods: Mature seeds were placed in mesh pouches on the soil surface and were retrieved periodically to assess residual hard seed proportions throughout the growing season(s) in four experiments conducted over 2018 and 2019. Key results: Patterns of seed softening among adapted cultivars of subterranean clover were consistent: initially high proportions of hard seed, followed by rapid softening from mid-summer to the end of autumn with the remnant portion of seeds remaining hard. In contrast, diverse patterns of seed softening were observed among serradella cultivars, ranging from highly soft-seeded through to high initial hard seed portions that either softened rapidly or softened over a lengthy period. Rates of seed softening were faster in the warmer/drier environment of Cowra compared to the wetter/cooler environment of Canberra. Conclusions: The study revealed seed softening patterns among serradellas to be diverse and different to subterranean clover. This will affect management and suitability of serradella cultivars for permanent pastures. Implications: In permanent pastures, serradellas that soften slowly over several years are likely to have limited regeneration in the year after pasture establishment with a high potential for weed invasion. Serradella has many advantages as a pasture legume, however persistence and productivity in permanent pastures can be inadequate. This study quantified seed softening of serradella species in comparison with subterranean clover in the Southern Tablelands and Central Slopes districts of eastern Australia. Diverse patterns of seed softening were observed among serradella cultivars, in contrast to subterranean clover. Implications for pasture establishment of serradella in high rainfall zone permanent pastures is discussed. [ABSTRACT FROM AUTHOR]