this was demonstrated by the use of isotope techniques in three different disease situations : ( a ) in primarily infected leaves 8-10 days after infection , ( b ) in secondarily infected leaves 2 mo after infection , and ( c ) in stable green areas ( `` '' true dark green islands '' '' according to the terminology of atkinson and matthews , 1970 ) of leaves exhibiting mosaic symptoms .
C0012634
disease
C0009450
infection