Abstract
Ten wheat varieties showed differential growth behaviour' for shoot dry matter (SDM), root dry matter (ROM), P
uptake and P utilization index at stress (rock-P) and adequate (soluble-P) P levels. SDM had fallen between 0.42
(Inqulab 91) and 0.79 g plant" (Blue Silver) at stress P level Differences in SDM manifest the existence of
genetic variability among wheat varieties, which was also evident from highly significant correlation of SDM with
relative shoot biomass production (r = 079, p<0.01) and P utilization efficiency (r = 0.84, p<0.01). Differences in
(ROM)) were also prominent and ranged between 0.19 (Inqulab 91) and 0.31 g plant" (Lu26s) Results are
evident that wheat varieties producing high amount of SDM were lower in ROM production at stress-P level This
variation in shoot and root biomass production might be due to adaptation mechanism. Results suggested that
better performance of some wheat varieties at stress-P level was because of their better P uptake and utilization
efficiency. The ranking of wheat varieties on the basis of relative SDM production in descending order was FSD
85 > WL 711 > 90A204 > Blue Silver> PAK 81 > V 88220-8 > Lu26s > Parwaz 94 > 89A053 > Inqulab 91. The
varieties, which performed better at rock-P level could be successfully grown under low soil P conditions
Key words: Wheat varieties, rock phosphate, phosphorus utilization index
