Pale green and sunken patches between veins are early symptoms of
Mg toxicity (J.
Brown to black spots in interveinal areas spread and join together
older leaves develop first pale, angular patches and then small
dark spots on interveinal
veins on the undersurface
of the older leaves may turn black.
severely affected leaves turn yellow and fall off.
young leaves may develop pale interveinal chlorosis,
due to induced iron deficiency.
with other symptoms
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