How to classify viruses ? What nomenclature to use ?
Virology is a recent subject. One could expect a structured nomenclature and a well codified use. This is not the case, but the subject benefits from mitigating circumstances.
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Introduction aux sciences du vivant
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Différentes disciplines scientifiques, relevant de la biologie, étudient les espèces nuisibles ou utiles aux plantes cultivées ou sauvages.
- La malherbologie pour les mauvaises herbes ou les plantes envahissantes
- L'entomologie pour les insectes mais aussi les autres arthropodes nuisibles (myriapodes, acariens...) et les auxiliaires utiles.
- La nématologie pour les nématodes
- La bactériologie pour les bactéries
- La mycologie pour les champignons
- La virologie pour les virus et viroïdes
Et la phytopathologie qui consiste à diagnostiquer les maladies des plantes causées par des pathogènes (bactérie, champignons et virus). Cette discipline fait intervenir la bactériologie, la mycologie et la virologie.
Why study plant viruses ?
Virus diseases of plants have an important economical effect. They cause a reduction of the plant’s strength and very often modify the aspect of certain plant organs. In all cases, a decrease of more or less importance in yield is observed.
Read moreWhat is a viroid and how does-it differ from a virus?
Viroids have been discovered in 1971 by the specialist of plant diseases T. O. Diener. These particles, smaller than viruses, are made of a single stranded RNA and do not have protein coat (capsid).
Read moreWhat is a virus ?
Viruses are pathogenic organisms of very small dimension, invisible to optical microscopes. They can’t multiply themselves out of a living cell, they are obligatory parasites.
Read moreWhat are the consequences of weediness ?
Losses in production due to weeds affect the world food production, but more particularly that of developing countries. It’s actually in tropical zone that the loss estimate is the highest: 25 % of production as opposed to 5 % in developed countries. Already in 1967, the first world analysis showed that in Africa, these losses were between 10 and 56%.
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