文献类型： 外文期刊

作者： Carswell, Alison ¹ ; Rafael Sanchez-Rodriguez, Antonio ² ; Saunders, Karen ¹ ; le Cocq, Kate ¹ ; Shaw, Rory ² ; Cotton, Joseph ² ; Zhang, Yushu ¹ ; Evans, Jess ⁶ ; Chadwick, Dave R. ² ; Jones, Davey L. ² ; Misselbrook, Tom ¹ ;

作者机构： 1.Rothamsted Res, Sustainable Agr Sci North Wyke, Okehampton, Devon, England

2.Bangor Univ, Sch Nat Sci, Bangor, Gwynedd, Wales

3.Univ Cordoba, Dept Agron, ETSIAM, Cordoba, Spain

4.Fujian Acad Agr Sci, Inst Soil & Fertilizer, Fuzhou 350013, Peoples R China

5.Univ Western Australia, UWA Sch Agr & Environm, Soils West, Perth, WA 6009, Australia

6.Computat & Analyt Sci Rothamsted Res, Harpenden, Herts, England

关键词： Fertiliser response; Livestock production; NUE; Partial factor productivity; Plant trait

期刊名称：EUROPEAN JOURNAL OF AGRONOMY （ 影响因子：5.722； 五年影响因子：6.384 ）

ISSN： 1161-0301

年卷期： 2022 年 133 卷

页码：

收录情况： SCI

摘要： To increase ruminant production efficiency, the environmental impact of growing forage must be reduced, through lowering system inputs and increasing crop resilience to extreme weather. Here we examined the role of red clover (cv. AberClaret) in minimising nitrogen (N) requirements, alongside two novel grass varieties, (1) a festulolium (cv. AberNiche), developed for drought tolerance, with potential for deep-rooting, and (2) a ryegrass hybrid (cv. AberEcho), developed for high-sugar content, which may enhance ruminant N-uptake in-vivo. Field trials were conducted at two UK sites, growing festulolium and ryegrass +/- red clover (at 29% of the seed mix weight) at a range of N fertilisation rates (0 - 600 kg N ha(-1)) for 2 years (six harvests). We assessed sward performance (N offtake, herbage quality, and grass N use efficiency), rooting depth and N transfer from clover to grasses using N-15 natural abundance. Across both sites and years, dry matter yield and herbage-N content were overall greater from the swards that included clover. Dry matter yields from festulolium were not greater than from ryegrass under the drought conditions experienced in 2018, despite its greater root mass. Agronomic efficiency of fertiliser N was similar between grasses (19 - 22%), however the festulolium more effectively used endogenous soil N than the ryegrass. Inclusion of clover in the sward affected forage quality, with increased crude protein and metabolisable energy content and reduced sugar and fibre (NDF) content. Among the grass types, metabolisable energy was greater and NDF content less for ryegrass than for festulolium. A strong reliance on biological N fixation (80 - 94%) for clover was observed, however, N transfer from clover to the neighbouring grass was not evident from the delta N-15 signatures. We conclude that red clover is a viable fertiliser-N replacement strategy in short-term leys, and that grass varieties with improved herbage quality may provide a better option for optimising sward performance than drought tolerant grass varieties.