Wheat roots proliferate in response to nitrogen and phosphorus fertilisers in Sodosol and Vertosol soils of south-eastern Australia

摘要: Root growth responses to separately placed of bands N and P fertiliser were examined at the 3-leaf (GS13) stem extension stages (GS30) for wheat (Triticum aestivum L. cv. Yitpi) growing in 2 major alkaline soil types from rainfed (375–420 mm) grain production regions south-eastern Australia. Intact cores a Sodosol Vertosol destructively sampled changes root length density (RLD) diameter distribution within profile using restricted maximum likelihood analysis principal component analysis, respectively. At GS13, RLD increased when only was applied, although there no shoot response. The response consisted spatially generalised increase RLD, rather than specific vicinity band. There substantially greater, but still generalised, both (without P). classes changed with depth GS13 otherwise similar, regardless treatment. GS30 also proliferation topsoil, detectable fertiliser-specific location or structure system. Shoot similar level plants supplied N, irrespective P, distributions again insensitive Plants responded by increasing relatively fine roots (100–250 μm), which style acquisition strategy that possibly triggered moisture limitations. Consequently, under realistic semi-arid conditions did not follow expectations based on nutrient studies. Instead, roots, apparently better compete finite water nutrients.