Contribution a l’etude des maladies foliaires des cereales "approche a l’etude epidemiologique et identification de la jaunisse nanisante de l’orge dans les cereales d’hiver dans les regions de L’est D’Algerie

Abstract EN

These attacks cause significant losses when susceptible varieties are used and environmental conditions are favorable.

The investigations carried out during the last decade in some areas of potential cereal eastern Algeria (Constantine, Mila, Guelma, Annaba, S / Ahras, El Tarf) indicate the risks of epidemic development of certain fungal diseases (rust yellow blotch, septoria, etc.

..), if adequate measures of prevention and intervention are not taken in time [1,2].

Crop losses resulting are estimated at over 40% for septoria and rusts, are around 25-35% for cavities and coals [3].

In favorable years the Yellow rust, can take extents epidemic and destroy entire harvests.

In the serological tests carried out by ELISA, BYDV was identified on a large number of grain samples from the regions surveyed and its severity is related to its epidemiology correlated with high activity of aphid vectors of BYDV such: Rhopalosiphum padi , Rhopalosiphum maidis, Sitobion avenae, Schizaphis graminum, Duariphis noxia.etc.

Pathothypes plan, the PAV strain is identified in most cases the species tested at rates ranging from 26% to 57%.

Strain MAV has recognized very few samples of particularly hard wheats at rates higher or lower, ranging from 7% to 25% LTV on the strain is found in any species tested