Viruses Genomes - FABA BEAN NECROTIC YELLOWS VIRUS

Faba bean is the major food legume crop in Egypt, and its dry grain provides the main source of protein for most of the population. It also plays a key role in the biological nitrogen fixation process.

Grain production is affected by a number of diseases caused by either fungi or viruses however in 1992 a new disease began decimating plants, particularly in Middle Egypt. The symptoms were were severely stunted faba bean plants and premature death and it was confirmed to be Faba bean necrotic yellows virus(FBNYV) by researchers in 1993 which had not previously been reported in Egypt.

(FBNYV) is spread by aphids. It is considered the most economically important disease-inducing agent to the faba bean crop, especially in Middle Egypt. It is also economically damaging in the Jordan Valley and in coastal areas of Syria and Turkey where winters are sufficiently mild to sustain the aphid population. The aphids acquire the virus when feeding on virus-infected summer legumes, then they introduce the virus into faba bean plants when they start feeding on them in the Autumn. The virus is contained in the saliva of the aphid and transmitted while feeding takes place.

Due to the failure of 90% of the Egyptian faba bean crop in 1992 and the resultant economic losses, and further crop failure in 1999 Government and researchers are working on producing virus resistant varieties to try and eliminate the use of pesticides to reduce crop disease.

References:

http://www.icarda.cgiar.org/Publications/Caravan/Caravan12/Car124.Html
http://www.ictvdb.rothamsted.ac.uk/ICTVdB/00.093.0.01.003.htm#Infectivity
http://www.icarda.cgiar.org/ICARDA_photogallery/Constraints/Carv12-10b.jpg