Abstract
A portable soft X-ray apparatus was devised for the field observation of crop plants. This apparatus can be used for the internal diagnosis of crop plants through radiographs. For instance, the successive observation can be performed on the young ears surrounded by leaves and on the grains or seeds in glumes or pods. This apparatus can be successfully used in observing the effect of day-length or temperature treatment on the growth and in inspecting the internal defects of crop plants
