Effect of stem girdling on the carbohydrate content and nitrogenase activity of Pachyrhizus erosus (L.) urban nodules

carbohydrate content contenido de carbohidratos incision annulaire nitrogenasa nitrogenase nudosidades radiculares nutrient transport pachyrhizus photosynthese photosynthesis relaciones fuente sumidero relation source puits ringing root nodules saccharose source sink relations stems sucrosa sucrose tallo teneur en glucides tige transport des substances nutritives transporte de nutrientes tubercule tubers