Evaluation of Phosphorus acquisition in wheat genotypes

A factorial completely block design experiment was carried out to evaluate cereals genotypic variation in phosphorus (P) acquisition and utilization with 8 bread wheat (Triticum aestivum L.), 3 durum wheat (Triticum durum L.), 3 barley (Hordeum vulgare L.), 1 rye (Secale cereale L.), 1 oat (Avena sativa L.) and 1 Triticale (X Triticosecale L.) in two levels of P- fertilizer (0 and 84 mg P/kg soil) with 3 replication in green house during 2006. Genotypes showed significant differences in chlorophyll content, tillers, shoot P concentration and content (the total amount of P per shoot), fresh and dry weight. Also P efficiency (relative shoot yield) significantly differed among genotypes and ranged from 0.42 for a barley line (M- 80-16) and 0.97 for bread wheat cultivar (Azadi) with the average of 0.71. Shoot P concentration and content very significantly increased from 0.19% and 13.24 mg P/pot to 0.47% and 46 mg P/pot by applying P fertilizer, respectively. With no P supply (P0), durum wheat (Yavaroos) with 20.15 mg P/pot and a barley line (M-80-16) with 5.85 mg P/pot had the highest and the lowest P uptake among all genotypes. Oat produced the highest dry weight per unit of P uptake and hence was very efficient in P utilization. Azadi and Yavaroos with 0.45 and 0.43 had the highest relative P uptake respectively. Therefore, the mentioned varieties were efficient in P acquisition. There was no correlation between P efficiency and shoot P concentration of genotypes (r= 0.12), but the relationship between P efficiency and shoot P content (total amount of P per shoot) was highly significant (r= 0.66**). Therefore, in the coming research studies, both genetic characteristics (P-acquisition and P-utilization) are to be the focus of introducing high P-efficiency cereals.