Effect of phosphorus deficiency on carbon metabolism of bean (Phaseolus vulgatis) seedlings.

Phosphorus (P) is an essential nutrient for plants. There are genotypes of bean (Phaseolus vulgaris) that are less affected, but the lack of an adequate characterization of their biochemical responses to the lack of P has limited their use in breeding programs. In this article notable differences are reported among the genotypes Canario 60 (C60) and MAR1 to the lack of P: the dry weight of the root was reduced in similar proportions, but the impact on the aboveground part was greater in C60. The lack of P did not alter the relationship between soluble and total P in young leaves and mature leaves, but increased it in the root of MAR1. The lack of P modified the levels of glucose, fructose, saccharose and starch in leaves and roots. It is proposed that the efficient use of P, its mobilization from the root to the leaves, and the maintenance of the capacity to export photosynthates, are qualities of the plant that can improve the performance of the crop when the amount of assimilable P is not sufficient.