Differences of phosphorus uptake and utilization in wheat cultivars with different phosphorus use efficiency for grain yield

Through soil culture experiment, 130 wheat cultivars were used to evaluate their differences in dry matter weight, grain yield, phosphorus uptake and utilization at different growth stages. The tested wheat cultivars were classified into 6 types (i.e. Ⅰ, Ⅱ, Ⅲ, Ⅳ, Ⅴ and Ⅵ, Ⅰ was the lowest, and Ⅵ was the highest) based on their phosphorus use efficiency for grain yield (PUE for grain yield) by using the MinSSw method. The results are as follows: (1) Differences of PUE for grain yield of the cultivars used in this study are very large (CV=1660%), the averages of PUE for grain yield for Ⅰ, Ⅱ, Ⅲ, Ⅳ, Ⅴ and Ⅵ, are 13629, 15167, 16916, 18589, 20132, and 24466 g grain per gram of P. There is a significant positive correlation between PUE for grain yield and grain yield(r=03203**). (2) Significant differences are observed in phosphorus concentration and absorption of plants among the wheat types. There are significant correlations between plant phosphorus and PUE for grain yield at mature stage (r=06969**), and the same as grain yield and phosphorus absorption at heading and mature stages (r=02966*, r=09271**). (3) Significant differences are observed in phosphorus use efficiency for dry matter among six types at different growth stages. There is a significant correlation between PUE for dry matter and PUE for grain yield at the mature stage (r=07391**). (4) The dry weights are increased with PUE for grain yield at different stages. The phosphorus content is an important factor for grain yield formation from the jointing to mature stages, and high PUE for grain yield wheat type has strong capacity of material and grain yield formation after the jointing stage.