On the three species of Ascochyta on Pisum sativum

Abstract

1. Thee Ascochyta fungi parasitic on the pea have been studied by the writer.
2. The diseases caused by Ascochyla Pisi, A. Pinodes (Mycosphaerella Pinodes) and A. Pinodella are designated “blight”, “brown spot” and “foot rot” respectively.
3. The brown spot (A. Pinodes) is the most destructive of the three diseases in Japan.
4. On the leaf Ascochyta Pisi produces light-tan marginate spots which are distinguishable from purplish-brown irregular lesions caused by the other Ascochyta.
5. A. Pinodella and A. Pinodes form black lesions on the foot, and A. Pinodella rots the foot severely, while A. Pisi does not infect it.
6. The ascigerous stage has been found in culture and on the host only in A. Pinodes.