Genetic analysis of thrips resistance in cowpea (Vigna unguiculata [L.] Walp.)

Inheritance of cowpea resistance to flower thrips in Uganda germplasm

“…Similar gene action on the resistance of cowpea to flower thrips was reported by Dormatey et al (2015) in Ghana while evaluating the genetics of cowpea resistance to flower thrips. The estimate of Baker's ratio values were 0.75 for thrips damage score during the damage assessment dates ( Table 5), implying that the performance of a single cross progeny could be predicted fairly accurately based on the GCA of its parents (Oladejo et al, 2017). However, the location and GCA interaction effects were highly significant (P<0.001) for thrips damage scores, suggesting that the additive gene effects were more influenced by the environmental effects but SCA effects of the crosses were not significant for all the thrips counts assessment dates indicating no or small proportion of non-additive genes effects controlling flower thrips counts in flower.…”

“…This contradicted Omo-Ikerodah et al (2009) findings where reciprocal differences were important in conditioning resistance to flower thrips among cowpea genotypes. However, the occurrence of significant reciprocal by location interaction effects (Table 5) between the reciprocal families indicated that the expression of the cytoplasmic factors on thrips damage scores depended on the environmental factors as well as in the case of the nuclear genes (Boukar et al, 2013;Bett et al, 2017;Oladejo et al, 2017). Consequently, the use of the resistant genotype as female parent could confer superior resistance on the F2s in different locations.…”

“…However, more studies on the factors creating that situation could provide more explanation about it. Some crosses displayed significant and negative reciprocal effects for thrips damage score and thrips counts, suggesting that they were associated with maternal inheritance from the female parent (Omo-Ikerodah et al, 2009;Oladejo et al, 2017).…”

Les contraintes entomologiques de la culture du niébé et leur mode de gestion par les producteurs dans les régions de Maradi et Zinder au Niger

“…La pression des insectes ravageurs a été notifiée par plus de deux tiers des villages. Cette donnée corrobore les observations de plusieurs auteurs qui ont rapportés la sensibilité de cette légumineuse aux ravageurs (Dugjé et al, 2009 ;N'gbesso et al, 2013 ;Sreelakshmi et al, 2016 ;Issoufou et al, 2017 ;Oladejo et al, 2017 ;Rabe et al, 2017 ). Les producteurs au niveau des villages ont ressorti les deux ravageurs majeurs du niébé suivants :…”

Screening of cowpea (Vigna unguiculata (L.) Walp.) lines for resistance to three Aphids (Aphis craccivora Koch) strains in Burkina Faso

“…It rarely exceeds 400 to 500 kg per hectare in the traditional production system (Langyintuo et al, 2003). High yields in cowpea are seriously militated by insect pests and without insect control, yields range between 100 and 250 kg ha-1 (Oladejo et al, 2017). The cowpea aphid, Aphis craccivora Koch (Homoptera, Aphididae) is one of the insects causing serious yield losses in cowpea.…”