Chlorose is the name for the yellowing of the leaves and buds of the grapevine due to a shortage of chlorophyll (green pigments) production. This may be due to a lack of (absorption of) iron, nitrogen, sulfur, magnesium, or potassium, or due to the wrong pH of the soil. Waterlogging can make it particularly difficult for iron – which is necessary for the production of chlorophyll – to be absorbed by the grapevine. Chlorosis can also occur as a symptom in wood diseases such as Eutypa dieback or Botryosphaeria dieback.
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