Tropicultura (Jan 2008)
Inventaire des insectes ravageurs et vecteurs de la panachure jaune du riz dans les périmètres irrigués de Maga (Extrême Nord Cameroun)
Abstract
Inventory of Devastating and Vectorial Insects of The Rice Yellow Mottle Virus in the Irrigated Perimeter of Maga (Far-North of Cameroon). The present study was carried out in the research framework conducted by the Regional Center of Agricultural Research of Maroua. This investigation aimed at making an inventory of devastating and vectorial insects of the Rice Yellow Mottle Virus in the irrigated perimeter of Maga (Far-North of Cameroon). In order to attain this objective, two collection methods were used. These included collection by D-VAC and collection by the Sweep net. The collection of the insect species with the two methods was done at the different phonological stages of the rice plant (nursery, heading, booting and maturity). The principle was to choose randomly a reference plot for each transplanted rice batch in the irrigated perimeter of Maga. The insect identification key of Heinrich (10) and the family recognition key of Delvare et al. (5) were used to identify the different species collected. The insect inventory of rice in the irrigated perimeter of Maga showed that the species vary in abundance and quality with the different phonological stages of the plant. Also the abundance of the species at the different stages varied following the collection methods. The results of the inventory showed that 46 species belonged to 26 families (Cicadellidae, Pentatomidae, Delphacidae, Diopsidae, Chloropidae Chrysomelidae, Coccinellidae, Acrididae, Pyralidae, Noctuidae…) and 7 orders (Lepidoptera, Diptera, Orthoptera, Coleoptera, Hemiptera, Thysanoptera and Hymenoptera). The same inventory with the D-VAC and the Sweep net showed that the insects associated with the rice in the irrigated perimeter of the study area consisted of pest, of which some were vectors of Rice Yellow Mottle Virus (Nephottetis nigropictus, Oxya hyla, etc.) and natural ennemis of this pest.