Effects of phosphorus sources on phosphorus fractions in rhizosphere soil of wild barley genotypes with high phosphorus utilization efficiency. Effect of Phosphorus Application Rate on Dry Matter Accumulation and Phosphorus Utilization Efficiency in Oil Flax Evaluation of the phosphorus nutrient characteristics of maize inbred lines at the seedling stage Effect of different phosphorus levels on phosphorus nutrient uptake, transformation and phosphorus utilization efficiency of oil flax