TY - JOUR
T1 - Field benchmarking of the critical external phosphorus requirements of pasture legumes for southern Australia
AU - Sandral, Graeme A.
AU - Price, Andrew
AU - Hildebrand, Shane M.
AU - Fuller, Christopher G.
AU - Haling, Rebecca E.
AU - Stefanski, Adam
AU - Yang, Zongjian
AU - Culvenor, Richard A.
AU - Ryan, Megan H.
AU - Kidd, Daniel R.
AU - Diffey, Simon
AU - Lambers, Hans
AU - Simpson, Richard J.
PY - 2019
Y1 - 2019
N2 - 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.
AB - 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.
KW - critical soil test P
KW - Ornithopus compressus
KW - Ornithopus sativus
KW - phosphorus fertiliser
KW - serradella
KW - subterranean clover
KW - Trifolium subterraneum
UR - http://www.scopus.com/inward/record.url?scp=85073368423&partnerID=8YFLogxK
U2 - 10.1071/CP19014
DO - 10.1071/CP19014
M3 - Article
AN - SCOPUS:85073368423
SN - 1836-0947
VL - 70
SP - 1080
EP - 1096
JO - Crop and Pasture Science
JF - Crop and Pasture Science
IS - 12
ER -