
TY  - JOUR
A1  - Li, G. D. 
A1  - Helyar, K. R. 
A1  - Conyers, M. K. 
A1  - Cregan, P. D. 
A1  - Cullis, B. R. 
A1  - Poile, G. J. 
A1  - Fisher, R. P. 
A1  - Castleman, L. J. C. 
T1  - Potassium deficiency and its management in a long-term rotation experiment in the south-western slopes New South Wales
JF  - Australian Journal of Experimental Agriculture
JO  - Aust. J. Exp. Agric.
Y1  - 2001
VL  - 41
IS  - 4
SP  - 497
EP  - 505
KW  - 
UR  - https://doi.org/10.1071/EA00108 
N2  - Potassium (K) deficiency of wheat and pasture species was found at a site in the south-western slopes of New South Wales. The soil was a subnatric yellow sodosol. Subterranean clover (Trifolium subterraneum) was found to be less competitive for K in the soil compared with its associated grasses. Higher soil K concentrations were required to achieve the same subterranean clover K concentration in the grass&#8211;legume mixtures than in a subterranean clover monoculture. For wheat (Triticum aestivum) production, a soil exchangeable K (Kex ) below 0.25 cmol(&plus;)/kg appeared to be deficient for the limed treatments, but there was no obvious critical value for either limed or unlimed treatments. The critical K exvalues for the grass &ndash;legume mixtures could not be simply specified because the values were affected by competition between species growing in swards of variable botanical composition. An annual rate of 20 kg K/ha for the pasture&#8211;crop rotations (50/50%) and 29 kg K/ha for the permanent pastures was estimated to be sufficient to replenish the K losses from product removal and animal excreta transferred to campsites at this trial site. 
ER  -

