eng Science and Education Publishing World Journal of Agricultural Research 2333-0678 2017-07-18 5 4 212 220 10.12691/wjar-5-4-3 WJAR2017543 article Jehad Abbadi jihadabbadi@yahoo.com 1 Biology Department, College of Science and Technology, Al-Quds University, Jerusalem, Palestine The use of nutrient efficient alternative crops is a possible strategy of sustainable land use. Plant species vary in their phosphorous (P) use efficiency under suboptimal P supplies in different soils by using different strategies. Cultivating P efficient species to improve yields may be possible if P efficiency mechanisms are elucidated. Therefore P use efficiency of the alternative oil crops safflower and sunflower was studied under semi-controlled conditions in sandy and loamy soils using three P supplies. Both species responded strongly to increasing P supplies in both soils and performed better in loamy soil. In both soils, both species contained similar P concentrations in shoots at low P supplies, but safflower accumulated less P amounts in shoots than sunflower at all P levels. Sunflower had less external P requirements than safflower in both soils. Safflower had higher efficiency ratio than sunflower at low P supply in sandy soil, and less values in loamy soils. Safflower had lower utilization index than sunflower in both soils at all P levels. Safflower recovered less external P (added P, extractable-P, soil solution-P) than sunflower in both soils. The P use efficiency of crops is based on different competitive components. Neither safflower nor sunflower showed a combination of high values of all P use efficiency components in both soils at all P levels, but safflower was inferior to sunflower in most studied traits. Therefore safflower cannot be considered a low input species as compared to sunflower in terms of P uptake and utilization efficiency. http://pubs.sciepub.com/wjar/5/4/3/wjar-5-4-3.pdf sustainable agriculture phosphorous utilization efficiency alternative crops carthamus tinctorius helianthus annuus safflower