
%0 Journal Article
%A Brennan, R. F. 
%A Bolland, M. D. A. 
%T Lupin takes up less potassium but uses the potassium more effectively to produce shoots than canola and wheat
%J Australian Journal of Experimental Agriculture
%D 2004/04/30
%V 44
%N 3
%P 309-319
%K 
%R https://doi.org/10.1071/EA02232
%U https://www.publish.csiro.au/paper/EA02232 
%X We compared the potassium (K) response of canola (Brassica napus L. cv. Karoo), spring wheat (Triticum aestivum L. cv. Camm), narrow-leaf lupin (8 cultivars of Lupinus angustifolius L.), and yellow lupin (2 cultivars of L. luteus L.) in a glasshouse experiment. The following measures were used: yield without added K; K required for 75% of the maximum yield; K required to achieve a K concentration in shoots of 20 g/kg; K required to achieve a K content of 50 mg K/pot in dried shoots (K concentration multiplied by yield); and, for the L. angustifolius cultivars, the K efficiency ratio (yield for the nil-K treatment divided by yield for the largest amount of K applied).Both L. angustifolius and L. luteus used soil K and applied K more effectively than canola and wheat to produce shoots (measured from dried shoots of 42-day old seedlings). For all amounts of K applied, including the nil treatment, the K concentrations were higher in canola and wheat shoots than in shoots of the 2 lupin species. Consequently, the 2 lupin species were less effective than canola and wheat at taking up soil and applied K, but were more effective at using the K taken up to produce shoots. The most recent cultivar of L. angustifolius, cv. Kalya, was less effective than the older Merrit cultivar at using soil and applied K to produce shoots, therefore future cultivars need to be screened for their ability to use soil and applied K. The K efficiency ratio for L. angustifolius indicated cultivars Kalya and 2141 were inefficient and the following cultivars had similar medium efficiency values: Myallie, Tanjil, Tallerack, Quilinock, Belara and Merrit. As measured in 42 day old seedlings, the diagnostic critical concentration of K in shoots required for 90% maximum yield of dried shoots was about (g K/kg) 40 for wheat, 37 for canola, 16 for L. angustifolius and 14 for L. luteus. 
