Management of anthracnose disease of cowpea with three plant leaf extracts for enhanced grain yield in Abeokuta, Nigeria

The antifungal activity of aqueous three plants leaf extracts were tested against anthracnose disease of cowpea caused by Collectotrichum lindemuthianum. The experiment was laid out in a Randomized Complete Block Design (RCBD) with three replicates. Extracts of Azadirachta indica, Acalypha wilkisiana and Carica papaya were sprayed on cowpea (Ife brown) foliage. A total of four foliar sprays were applied: three wee ks after planting, flowering stage, at the initial podding stage and at the full podding stage. Benlate served as positive controls while distilled water was negative control. Results showed the disease incidence and severity as 23.67-46.67% and 1.07-1.93, respectively. Combination of the extracts resulted in significantly (p≤0.05) low incidence of anthracnose (66.67% reduction) and improved the yield of cowpea by 1.63 tons/ha (77.25% increase) compared with untreated control plots. Azadirachta indica, Acalypha wilkisiana and Carica papaya extracts, singly or in combinations, reduced incidence and severity of anthracnose which translated to yield increase. Keywords: Anthracnose, botanicals, Collectotrichum lindemuthianum, cowpea, and managemen

Effects of application of phosphorus fertilizer on brown blotch disease of cowpea

A field experiment was conducted to investigate the effects of level of phosphorus application on brown blotch disease of cowpea during the planting seasons of 2001, 2002 and 2003. Application of phosphorus from Single Super Phosphate at 30, 60, 90, and 120 kg P2O5/ha significantly increased the number of petioles, pods, nodules, seed/pod leaf area and yield. The higher the level of application of phosphorus the higher values of all the parameters. Disease incidence and severity of brown blotch were significantly reduced at higher levels of phosphorus (90 and 120 kg/ha) irrespective of the method of application. Moreover, there were also increases in the grain yield of cowpe

Prevalence and severity of bacterial blight and anthracnose diseases of cassava in different agroecological zones of Nigeria

Published online: 30 April 2008Geo-referenced surveys were conducted in 2001 and 2003 to assess the prevalence and severity of cassava bacterial blight (CBB) and cassava anthracnose disease (CAD) in different agro-ecological zones of Nigeria. A total of 132 fields were visited in 2001 as follow: humid forest (HF) 42, derived savannah (DS) 38, southern guinea savannah (SGS) 16, northern guinea savannah (NGS) 16 and Sudan savannah (SS) 20. In 2003, 277 fields were visited: HF (83), DS (143), SGS (22), NGS (11), and SS (18). CBB prevalence was greater than 70% in all ecozones in 2001; 33.7% in HF, 65.7% in DS and greater than 90% in others in 2003. CAD prevalence was greater than 90% in HF for the two surveys, 44.7% and 61.5% for 2001 and 2003 respectively in DS, while it was not observed in the other zones. In both surveys, more than 80% of CBB infected fields in all ecozones were moderately severe, except in SS where 47% of fields in 2003 were highly severe. In both HF and DS, more than 30% of fields in 2001, and less than 20% in 2003, had highly severe CAD symptoms. Prevalence of CBB was negatively correlated with annual precipitation and positively correlated with maximum temperature of the ecozones, while prevalence of CAD had strong positive relationship with the annual precipitation and negative association with maximum temperature. The distribution patterns of the diseases found in this study provide a baseline for disease management programme in the rapidly expanding cassava industry in Nigeria, and implications of the results for cassava industry were discussed

Genetic evaluation of cowpea (Vigna unguiculata (L.) Walp.) using morphological characters

The experiment was conducted to characterize cowpea (Vigna unguiculata (L.) genotypes based on morphological characters. The experiment was carried out at the screen house of the Institute of Agricultural Research and Training (IAR&T), Moor Plantation, Ibadan in 2015 and 2016 using nine (9) cowpea varieties. Soil was sieved with 2mm sieved and sterilized. The experiment was laid out in Completely Randomized Design (CRD) with four replicates. Morphological data were collected based on descriptor for cowpea (IBPGR, 1983). For quantitative traits, analysis of variance revealed that genotype and years effect mean squares from pooled data were highly significantly different for days to first and 50% flowering (P ˂ 0.01), interaction between genotype and years effect also had significant effect on days to first and days to 50% flowering (P ˂ 0.05).Higher significant values were obtained for terminal leaf width, pod weight, pod length, days to physiological maturity, total seed weight per plant, 100 seed weight and number of seed per plant in 2015 than the year 2016. However there were no significant differences obtained for terminal leaf length, pod per peduncle, number of pod per plant, seed length, seed width, seed thickness, and number of seed per pod in both years. Qualitative characters results show thatgenotypic effect, year effect and their interactions were not significant for plant vigour. Modupe, Ife 98-12, Oloyin-Pelebe, Ife BPC, Oloyin-Nla and Sokoto genotypes had intermediate twining tendency. Drum and Mulla had pronounced twining tendency while Ife Brown had no twining tendency. Based on pooled cluster analysis the dendrogram grouped the varieties in two different major clusters A and B. Cluster A comprised of seven genotypes; Oloyin-Nla, Oloyin-Pelebe, Sokoto, Ife BPC, Modupe, Ife 98-12 and Ife Brown. Cluster B comprised of two genotypes; Drum and Mulla. This implies that genotypes within the same cluster had similar genetic background, while genotypes in cluster A are distant on the chromosome as compare to genotypes on cluster B respectively.Keywords: Genetic evaluation, Vigna unguiculata, Cowpea, Morphological Character