Evaluation of common bean genotypes for phosphorus use efficiency

A greenhouse experiment was conducted to evaluate phosphorus (P)-use efficiency of 10 promising genotypes of common bean (Phaseolus vulgaris L.) with short and normal growth duration. The genotypes were grown on an Oxisol at 25 me; P kg(-1) (low P) and 150 mg P kg(-1) (high P) of soil. Shoot and root dry weight, root length, P concentration in the shoot, and P uptake in the shoot were significantly (P<0.01) affected by soil P concentration and genotype. However, P level did not effect root length and genotype had no effect on root dry weight. On the basis of P-use efficiency (mg dry weight of shootimg P accumulated in the shoot) genotypes were classified as efficient and responsive (ER), efficient and nonresponsive (ENR), nonefficient and responsive (NER), and nonefficient and nonresponsive (NENR). From a practical point of view, genotypes which produce a lot of dry matter in a soil with a low P level, and respond well to added P are the most desirable because they are able to express their high yield potential in a wide range of P environments. Novo Jalo and Perola genotypes fall into this group. Genotypes Irai, Jalo Precoce and L93300166 fall into the ENR group. Genotypes Carioca,Rosinha G-2, and Xamengo were classified NER, whereas, genotypes L93300176 and Diamante Negro were classified as NENR. There were no differences between short and normal growth duration genotypes in P-use efficiency.