Chlorosis

This article is about plant disease. For chlorosis (bleaching) in humans, see iron deficiency anemia .

Capsicum annuum , left chlorotic, right healthy leaf

The chlorosis - bleaching - is a disease symptom caused by a lack of chlorophyll (deficiency symptom) in land plants , e.g. B. in grapevines .

Appearance

The disease is noticeable through a characteristic damage pattern. Chlorosis is usually associated with a characteristic yellow coloration of the leaves and often up to burn-like leaf damage and can lead to necrosis (death of the leaf tissue). It is usually a sign of a lack of minerals, especially boron, iron, magnesium, sulfur or nitrogen, and often indicates that the soil has too high a salt content. Persistent drought stress can also lead to chlorosis, because it means that the nutrients are no longer transported in sufficient quantities.

Possible causes

Chlorotic vines

• genetically controlled and energy-dependent aging process ( senescence )
• Deficiency diseases (nitrogen, iron, magnesium, calcium, potassium). These nutrients can cause chlorosis-like symptoms on leaves.
• Poisoning by herbicides or biurets
• Abiotic stressors such as lack of water, overexposure, excess salt, exposure to strong UV radiation , gamma radiation , ozone
• strong temperature fluctuations
• Infections with subsequent inhibition of chlorophyll synthesis
  • Blocking of electron transport in photosystem I or II
  • Damage to the membrane system of the chloroplasts (including lipid oxidation ) by toxins (excretions or new formation due to intervention in synthesis processes)
• Plant virus infestation
• chalky water when kept as a houseplant

Some grape varieties are particularly susceptible, for example Müller-Thurgau , Grüner Veltliner , Pinot Noir and Traminer .

See also

• Citrus cancer
• Xylella fastidiosa # Pierce's disease

literature

• Karl Bauer, Ferdinand Regner , Barbara Schildberger: Viticulture . 9th edition. avBook published by Cadmos Verlag, Vienna, 2013, ISBN 978-3-7040-2284-4 .
• Horst Dietrich Mohr: color atlas diseases, pests and beneficial insects on the grapevine , 2nd edition, 2012, Eugen Ulmer Verlag Stuttgart, ISBN 978-3-8001-7592-5 .
• Gerhart Drews , Günter Adam, Cornelia Heinze: Molecular Plant Virology, Berlin 2004, p. 16ff ISBN 3-540-00661-3 .

Web links

Commons : Chlorosis  - collection of pictures, videos and audio files

• ( Page no longer available , search in web archives: chlorosis on grapevines - Lower Austria vine protection service )

Individual evidence

1. ↑ Gerhart Drews , Günter Adam, Cornelia Heinze: Molecular Plant Virology, Berlin 2004, p. 16ff., ISBN 3-540-00661-3 .
2. ^ Karl Bauer, Ferdinand Regner , Barbara Schildberger: Weinbau , avBuch im Cadmos Verlag, Vienna, 9th edition 2013, ISBN 978-3-7040-2284-4