The accumulation of dry matter and phosphorus efficiencies in wheat chromosome B ditelosomic lines under both sufficient- and low-Pi conditions

Chinese spring (CS) and ditelosomic lines (DL) from B chromosome (1BS-7BS, 1BL-7BL) were used to investigate the accumulation of plant dry matter and phosphorus efficiencies under sufficient-Pi and low-Pi conditions by hydroponics experiment. Compared with CS, the plant phenotypic features and dry weights of 4BS, 6BS, 3BL and 7BL under sufficient-Pi condition and those of DL 4BS, 6BS, 7BS and 7BL under low\|Pi condition were stable. The phenotypic features in the other DLs became worese and the dry weight decreased significantly at both Pi\|supply conditions. The P accumulation amount per plant in the tested DLs displayed a decreasing trend compared with CS under both Pi\|supply conditions, suggesting that the deletion of long or short chromosome B arms in wheat were involved in regulating accumulation of phosphorus in the plant. Under sufficient-Pi condition, the total P contents in 4BS and 4BL were significantly higher than that in CS, whereas that in 5BS was significantly lower than that in CS. Under low-Pi condition, the total P content in 5BS was significantly higher than that in CS, whereas that in 3BL and 5BL were significantly lower than that in CS. Compared with CS, the tested DLs relatively showed a higher variation range in plant P usage efficiencies under both sufficient\| and low-Pi conditions, and generally demonstrated a reverse tendency of P accumulation amount in each line of the plant. The P use efficiencies in 3BS and 5BS were higher than that in CS under sufficient-Pi condition, whereas P usage efficiencies in 4BS, 1BL, and 4BL were higher than that in CS under low\|Pi condition. Supply with sufficient Pi or low Pi also changed the efficiencies of N- and K-usage in the DLs to the extent. Positive correlations are significantly observed between plant dry weight and P accumulation, as well as plant dry weight and plant leaf area. Therefore, our results indicate that wheat DLs with deletion play an important role in mediating plant responses to external Pi and genetically in regulating P use efficiencies. Leaf area per plant could be used for evaluating plant P use efficiency under both sufficient\| and low-Pi conditions.