Importance des cercosporioses de l'arachide et sélection des variétés pour la résistance aux maladies au Bénin

Abstract

Importance of Early and Late Spots of Groundnut and Selection of Varieties for Resistance to the Diseases in Benin Early and late leaf spots of groundnut are important diseases that cause high yield losses around the world. The objectives of this study are to evaluate the spatial distribution of early and late leaf spots of groundnut in Benin and to test 14 varieties of groundnut for their resistance to the disease. For this purpose, a survey was conducted in August 2016 on 72 groundnut production sites located in four agroecological zones of Benin. At each site 30 plants were randomly inspected along the diagonals of the field to assess incidence and severity. Also, the screening for resistance trial was carried out under greenhouse and field conditions at the experimental farm of the University of Parakou from July to October in 2015 and 2016. The analysis shows an average incidence of 94.02% and an average severity of 45.01% for the southern Guinean savannah, while the coastal savannah has an average incidence of 90.02% and an average severity of 56.62%. The northern Guinean and Sudanese savannas follow with incidence values of 87.14% and 86.80% and severities of 32.48% and 37.22% respectively. Among the varieties tested, 73.9.11, 57.313 and H.75.0 moderately resistant to resistant under inoculation and natural infection have medium to very high yields. The susceptible variety TS 32.1 has a very high yield. Varieties with moderate symptoms and medium to very high yields may be recommended to farmers.

Keywords

• groundnut
• early and late spots
• variety
• agroecological zone
• benin