Screening of Cowpea (Vigna unguiculata ( L.)Walp) Varieties for Resistance to Leaf Spot in Southern Guinea Savannah Agro- Ecology of Nigeria

Abstract

Five cowpea varieties (Vigna unguiculata (L.) Walp) namely UAM 09 1055-6, UAM 09 1051-1, IT 99k-573-1-1, IT 90k-277-2 and IT 99k-573-2-1 were investigated for fungi associated with the seed, leaf spot disease incidence and severity in Makurdi (07o 45’- 7o 50’N and 08o 45’ - 08o 50’E ; 98 m)and Otobi (7°07’ - 7°11'N and 8° 05- 8°10'E) in Benue State, Nigeria under natural infection. The effect ofleaf spot incidence and severity on the growth and yield of cowpea varieties were also evaluated. Fungi associated with the seeds and leaf spot lesions were isolated and identified. Diseased leaf samples from the study locations were found to be infected with Fusarium verticillioides, Curvularia lunata, Aspergillus tamarii Kite, Lasiodiplodia theobromae, Aspergillus flavus Link and Aspergillus niger van Tiegh, Pythium spp, Fusarium solani, Macrophomina phaseolina and Phoma sp. Otobi field had significantly higher incidence and severity of leaf spot disease than the Makurdi field. Cowpea variety IT 99k-573-1-1, IT 99k-573-2-1 and IT 90k-277-2 were classified as moderately resistant in Makurdi with a mean incidence of 22.23%, 16.97% and 16.67% respectively while varieties UAM 09 1051-1 and UAM 09 1055-6 were classified as Moderately susceptible and Highly susceptible with mean leaf spot incidence of 41.67% and 99.17% respectively. In Otobi, all the cowpea varieties screened were classified as Susceptible to leaf spot incidence with the exception of variety IT 90k-277-2 which was classified as moderately susceptible to leaf spot disease.
 Key words: Cowpea, leaf spot, screening, resistant, susceptible.

Assembly, Annotation, and Comparative Whole Genome Sequence of Fusarium verticillioides Isolated from Stored Maize Grains

“…Fusarium fujikuroi species complex (FFSC) is a well-known group of plant pathogenic fungus that has the potential to produce mycotoxins in different agricultural products [ 2 ]. The FFSC contains phylogenetically distinct species, F. verticillioides (teleomorph, Gibberella moniliformis ), F. fujikuroi , F. proliferatum , and F. subglutinans , that can infect agriculturally important crops such as maize, rice, sorghum, and beet [ 3 ], wheat and barley [ 4 ], cowpea [ 5 ], and a variety of ornamental crops [ 6 ].…”

IMA Genome - F16

“…The disease causes 35 to 40% yield loss in susceptible varieties (Fery et al 1976 ; Schneider et al 1976 ). In addition, black leaf mould incidence on cowpea limits the leaf area available for photosynthesis resulting in reduced yield (Booker and Umaharan 2007 ; Ekhuemelo et al 2019 ). Therefore, there is a need to understand the genome organization of Pseudocercospora cruenta that could assist in identifying the virulence gene(s) that control the disease.…”