Sentence:  After these treatments the conjugate did not stain healthy or <WSD>crown</WSD> gall sweet clover tissues or stained them a very faint green which was easily distinguishable from the bright yellow-green specific staining . 
Meaning of the word marked with <WSD> tags:  a bacterial disease of plants (especially pome and stone fruits and grapes and roses) which forms excrescences on the stem near the ground