Relationship between tuberization and the appearance of a neutral invertase activity in Pachyrhizus erosus (L.) Urban

Changes in soluble carbohydrates and PAGE pattern of tap root proteins were monitored in yam bean [Pachyrhizus erosus (L.) Urban] tap root under induc tive (short days) acid non-inductive (long days) environments. Up to five w eeks alter sowing (WAS), tap roots contained essentially sucrose. Under the short-day environment, a neutral invertase (NI) activity appeared from 6 W AS, concomitantly with glucose and fructose accumulation. Under the long-da y environment, soluble carbohydrates as well as the pattern of proteins rem ained unchanged throughout root development. from these data it is conclude d that NI controls the accumulation of hexoses in tap roots and is regulate d by short days.