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Cowpea (Vigna unguiculata) is an important tropical legume crop contributing significantly to food security in tropical regions. The present study was carried out to determine the extent of genetic variation, to estimate character associations, heritability and genetic advance of 25 quantitative traits in 30 genotypes of cultivated Vigna unguiculata from the western highland region of Cameroon. These quantitative traits were selected among cowpea descriptor lists. For all these traits, the analysis of variance showed significant difference among genotypes, highlighting the existence of important genetic divergence among the studied accessions. The highest phenotypic and genotypic coefficient of variation was observed in grain yield, pod yield and 100 seed weight. Genetic advance of these three characters was also the highest. Broad sense heritability was high in general, with 20 traits out of 25 having heritability values greater than 70%. This high heritability indicates little influence of the environment on these characters in cowpea. The highest heritability was recorded for 100 seed weight (98.15%) and the lowest for shoot weight (41.38%). At 0.05 probability level, grain yield correlated significantly with 21 out of the 24 other quantitative traits. Among others, grain yield correlated positively and significantly with 100 seed weight, number of pods per plant, number of branches per plant, number of nodes per plant, plant height, plant width, pod length, pod width, seed length, seed width and number of seeds per pod. These positive correlations between grain yield and many other traits indicate that a selection program based on any of these traits will result in increasing yield. Cluster analysis using UPGMA method revealed five distinct clusters. Genotypes named KEBCP025, KEB-CP006, KEB-CP098, KEB-CP070, and more importantly KEB-CP054 and KEB-CP004, were grouped in a single cluster and were characterized by a significantly higher grain yield, pod yield, number of pods per plant, number of seed per pod, plant height, pod length and pod width compared to other clusters. Accessions KEB-CP036 and KEB-CP031 produced significantly more important fresh biomass. These genotypes could be used as parents in genetic improvement programs aiming to increase yield and fresh biomass in cowpea.

Characterization of the genetic diversity and analysis of the genetic relationship between accessions of a crop species is a key step in breeding superior cultivars. The main objective of the hereby study was to determine the genetic variation between 30 cowpea accessions collected throughout the eight divisions of the Western Region of Cameroon using qualitative traits. Phenotypic variation of these accessions was evaluated using diversity indices and cluster analyses. A total of twenty qualitative traits were used for the study. Fifteen of them (75%) were polymorphic, displaying each at least two phenotypic classes. The monomorphic characters were growth pattern, leaf color, leaf hairiness, plant hairiness and pod hairiness, each with only one phenotypic class. Results showed a relatively significant level of genetic diversity among the studied cowpea accessions. Overall, the average of the observed and effective number of phenotypic classes per qualitative trait were Na = 2.350 and Ne = 1.828 respectively. The Nei's genetic diversity and the Shannon weaver diversity index were He = 0.369, ranging from zero (monomorphic trait) to 0.655 (growth habit) and H' = 0.609, ranging from zero (monomorphic trait) to 0.996 (seed crowding), respectively. The dendrogram constructed from the twenty qualitative traits revealed 05 accessions clusters with the number of accessions in each cluster varying from one to eleven. Information obtained from this study is likely be useful for future cowpea breeding program.

Fluted Pumpkin known as Telfairia occidentalis is an important vegetable crop in the tropics, cultivated for its leaf vegetable and edible seeds. It is a plant with a wide range of virtues but nevertheless; it is threatened by large scale fungal attacks. In order to manage the problem of food security and meet up with the production of this crop, this study was carried out to assess the effect of animal manure on the incidence and severity of leaf spot disease of Fluted Pumpkin and to determine the pathogenicity test of white leaf spot in Dschang. This research was done in the Faculty of Agronomy and Agricultural Sciences experimental farms at the University of Dschang from November 2017 to May 2018. The field layout was Randomized Complete Block Design with three treatments (poultry manure, piggery manure and control) and three replications. Each replicate consisted of six plots, giving a total of eighteen plots per treatment. In each treatment, fluted pumpkin was spaced at 1 m × 1 m apart. Application of organic manure was done at 3 weeks after emergence and data collection were carried out weekly from 42 DAP. Pathogenicity test was conducted after the establishment of lesions on the leaves. Data were analyzed using descriptive and ANOVA. It was observed that piggery manure treatment had the highest disease incidence (DI = 86.89) compared to the control (DI = 85.42) and poultry manure (DI = 65.74). The pathogenicity test revealed that Phoma sorghina was the causal agent for leaf spot disease in fluted pumpkin with a frequency of 18. Disease incidence and severity was reduced in poultry manure, followed by the control with piggery manure having more disease. Therefore, poultry manure had a better man-How to cite this paper: