抄録
When midribs of leaves of local lesion hosts were inoculated with TMV, necrosis appeared on the midribs. However, necrosis did not appear on the midribs when they were detached from the leaf tissues and were inoculated with TMV, although TMV multiplied in the midribs. It is postulated that necrotization of the inoculated midribs is caused by some chemical substances, probably by polyphenol or by other low molecular substances which have moved from adjacent green tissues.
