Effect of tillage on the growth and yield of cowpea varieties in Sudan savanna agroecology of Northern Nigeria

Field study was conducted during the rainy seasons (July-November) of 2007, 2008, 2009 and 2010 at the Research Farm of the International Institute of Tropical Agriculture (IITA) Minjibir, Kano State, Nigeria; to compare responses of six cowpea varieties to tillage. The treatments consisted of tillage systems (zero tillage, flat tillage and ridge tillage) as the main plot and cowpea varieties (IT89KD-391, IT90K-277-2, IT97K-461-4, IT97K-499-35, IT98K-131-2, and IT98K-506-1) as the sub-plot. The treatments were arranged as split plot laid out in a randomized complete block design with four replications. Zero tillage was significantly superior in influencing days to maturity, canopy height, intercepted photosynthetic active radiation (IPAR) and leaf area index but not total dry matter and grain yield of cowpea. A positive and significant association was recorded for days to physiological maturity and canopy height across the tillage systems with a correlation coefficient of ≤ 40% for days to maturity and ≥50% for canopy height. Though flat tillage showed a positive correlation with intercepted photosynthetic active radiation (IPAR) and leaf area (LAI), but this association was not significant. However, ridge tillage showed a positive and significant correlation with IPAR and LAI (r =0.378*** and 0.384***). All the tillage systems showed a high and significant positive correlation with cowpea dry matter and fodder yield (r= 0.54*** to 0.77***). Across varieties, grain yield was better with flat tillage than zero and ridge tillage systems, with 10% yield advantage over the two. Zero and ridge tillage were similar in their effects on grain yield. Except for IPAR, LAI and total dry matter (TDM), the interaction effect of cowpea varieties and tillage systems was significant. Our result point to the fact that extensive soil tillage (especially, conventional tillage) may not be necessary for cowpea production in this agro-ecology with a high percentage of sand and a sandy loam as soil textural class. Following our result, we may recommended varieties for the different tillage systems as follows: IT98K-131-2, IT97K-461-4, IT90K-277-2, IT98K-506-1 (grain) and IT89KD-391/IT97K-461-4 (best for fodder) for zero tillage system; IT90K-277-2, IT97K-499-35, IT98K-131-2 and IT98K-506-1(grain) and IT89KD-391/IT97K-499-35 (best for fodder) for flat-tillage; IT98K-131-2, IT90K-277-2, IT98K-506-1 and IT97K-464-4(grain) and IT90K-277-2/ IT89KD-391 (best for fodder) for ridge tillage

Differentials in Adoption of Cassava Post-Harvest Processing Technology among Farmers in South Eastern, Nigeria

The study examined factors influencing the adoption of cassava post-harvest processing technology among farmers in Abia North, Abia state, Nigeria. One hundred and fifty (150) farmers were randomly selected from five Local Government Areas of the state. Data analysis involved descriptive statistics and adoption model using logit regression. The results showed that majority of the famers were male who are still productive, married with large household sizes. Most of the farmers adopted cassava processing technologies and utilized the garri product. The results also indicated that income level of the farmer, number of processing equipment, household size and years of experience in farming business positively influenced the adoption of post-harvest processing technology among households in the study area and were each significant at 5 percent.  The study call for policies aimed at increased awareness programmes and subsidies on processing machines to increase their adoption. Keywords: Cassava, Adoption, Utilization, Post-Harvest Technology, Abia Stat

Evaluation of a new formulation of atrazine and metolachlor mixture for weed control in maize in Nigeria

Field studies were conducted in 2002 and 2003 at Ibadan, Nigeria, to evaluate the effects on weed control in maize of a new formulation of a mixture of atrazine and metolachlor. The treatments were the new formulation of the mixture at doses from 1.0 to 4.0 kg a.i. ha–1 and the old formulation of the mixture at the recommended dose of 2.5 kg a.i. ha–1. The new formulation of the mixture gave complete control of Panicum maximum, Commelina benghalensis, sedges (Mariscus alternifolius, Kyllinga squamulata, and Cyperus spp.), and Tridax procumbens, and good control (>94%) of Passiflora foetida at 4 weeks after treatment (WAT) in 2002. At 8 WAT, the new mixture gave good control (>73%) of P. maximum and C. benghalensis in 2002, and of P. foetida, sedges, and T. procumbens in both years. The hoeweeded control and all herbicide treatments at 4 WAT had lower weed dry matter than the untreated control in both years, and at crop harvest in 2002. In both years, the lowest weed dry matter was obtained from the hoeweeded control at crop harvest. In 2003, the old formulation of the mixture at the recommended dose had similar weed dry matter with the new formulation at all doses. The treatments did not significantly affect maize grain yield in 2002. However, in 2003, the new formulation of the mixture at a dose of 4.0 kg a.i. ha–1 and the hoeweeded control had 33% higher maize grain yield than the untreated control. The new formulation of a mixture of atrazine and metolachlor is effective for weed control in maize at lower doses than the recommended dose of the old formulation

Effect of level and source of shade on the biomass of speargrass in Nigeria

yields, there are almost no data to demonstrate this relationship. Most studies show that banan

Integrated management of cogongrass [Imperata cylindrica (L.) Rauesch.] in corn using tillage, glyphosate, row spacing, cultivar and cover cropping

Cogongrass [Imperata cylindrica (L.) Raeusch.] is a major weed in the tropics where land is intensively cultivated and fallow duration is less than 5 yr. Field studies were conducted in 1999 and 2000 in Nigeria to evaluate cogongrass response to combinations of five weed control options. Treatment combinations were tillage (hoe tillage and no-tillage), corn (Zea mays L.), row spacing (50 and 75 cm), corn cultivar [open-pollinated (OP) and hybrid], herbicide (glyphosate and no glyphosate), and cover crop {velvetbean [Mucuna cochinchinensis (Lour) A. Chev] and no velvetbean}. The treatment combinations were arranged in a randomized complete block design with three replications. Integrating tillage, herbicide, and cover cropping with velvetbean gave optimal control of cogongrass. Corn height and leaf area were negatively correlated with cogongrass shoot, rhizome, and total biomass. Corn grain yield was negatively correlated with cogongrass shoot biomass and total cogongrass biomass (shoot + rhizome). Good control of other weeds was achieved through the use of narrow corn row spacing and cover cropping with velvetbean. Tillage, narrow corn row spacing, and the use of herbicide had a positive effect on corn grain yield. The use of competitive cultivars, narrow row spacing, cover crop, and herbicide may be sustainable approaches to the control of cogongrass and other weeds in corn

Effect of Level and Source of Shade on the Biomass of Speargrass in Nigeria

Field studies were conducted in Oyo, Nigeria, to determine the effect of level and source of shade (polyethylene plastic fabric and velvetbean canopy) on the dry matter of speargrass (Imperata cylindrical (L.) Raeuschel). Shade levels provided by the plastic fabric were 0 (full solar radiation), 50, 75 and 88% of the incident solar radiation. Velvetbean shade levels of 40.5 to 97% were provided by densities of 4, 8, and 16 plants m-1. In 1999, the velvetbean canopy intercepted 40.5% of solar radiation at 3 weeks after treatment (WAT) and 82% between 5 and 11 WAT. At 11 WAT, velvetbean shading reduced the speargrass biomass by 48% and shade from plastic fabric by 41%. In 2000, radiation interception by the velvetbean canopy was 86.7-97.2% between 3 and 11 WAT. Shade from the velvetbean canopy reduced speargrass biomass by 90% and shade from plastic fabric by 44% at 11 WAT. Velvetbean biomass and LA1 were negatively correlated with speargrass biomass (r = -0.85 to -0.91, P<0.05) and incident solar radiation (r = 0.46 to 0.79, P = 0.05). The similarity of the effects on speargrass biomass of shading by plastic fabric and velvetbean indicated that shading was the principal mechanism by which velvetbean suppresses speargrass

Cogongrass suppression by intercropping cover crops in corn/cassava systems

Cogongrass is a difficult weed to control in small-scale farming systems and often causes significant crop yield reduction. Field experiments were conducted from 1996 to 1999 at three sites located in the forest/savanna transition zone of Nigeria to determine the influence of intercropping cover crops on cogongrass, corn, and cassava growth. Total cogongrass biomass (shoots and rhizomes) at the onset of the study was highest at Ijaiye (889 g m−2), followed by Umumba (445 g m−2), and least in Ezillo (138 g m−2). Velvetbean had the highest percent ground cover at Umumba and Ijaiye (67 to 89%) 10 wk after planting and shaded the ground longer at all locations. Twelve months after planting, plots with cover crops had 66, 71, and 52% lower cogongrass biomass than the weedy control without cover crops at Ijaiye, Umumba, and Ezillo, respectively. Velvetbean at all locations, L. purpureus at Ijaiye, and tropical kudzu at Umumba and Ezillo were the cover crops most effective in reducing rhizome biomass of cogongrass. Annual weeds dominated the plots sown to cover crops after 2 to 3 yr. At Ijaiye and Umumba, cogongrass competition affected the yield of cassava more than the yield of corn. At all locations, cover crops and weeded control treatments had 27 to 52% more corn grain yield than the weedy control. At Ijaiye, corn grain yields from velvetbean and L. purpureus plots were similar to that from the weeded control plot. At Umumba, all plots with cover crops had corn grain yields similar to that of the weeded control. At all locations, almost all cover crop treatments had cassava root yields higher than the weedy control. Except at Ijaiye, root yields from weeded control plots were 17 to 88% higher than in cover-cropped treatments, suggesting competition between cover crops and cassava

Mucuna spp. suppresses speargrass (Imperata cylindrica) and increases maize yield

Speargrass, Imperata cylindrica (L.) Raeuschel, is a serious weed, threatening crop productivity in smallholder farms in West Africa. Since the use of more effective practices such as deep tillage and chemical control is beyond the means of resource-poor farmers who carry out most agricultural activities in this region, low-input alternative technology needs to be developed. Field studies were conducted during the 1993/1994 and 1995/1996 growing seasons to investigate the influence of three velvetbean accessions and two levels of fertilizer on the control of speargrass during the year of cover crop planting and one year later. The velvetbean accessions in 1993 were: Mucuna cochinchinensis and M. pruriens var. utilis. In 1995, M. pruriens var. IRZ was included in the study. M. cochinchinensis in 1993 and M. pruriens var. IRZ in 1995 had the highest ground cover rating early in the growing seasons whereas M. pruriens var. utilis had the lowest ground cover rating in both years. Inorganic fertilizer at30 kg ha- 1 each of N, P and K increased velvetbean ground cover by 2-22%, with M. cochinchinensis (14-22%) and M. pruriens var. IRZ (5-15%) showing the highest response in 1993 and 1995, respectively. M. pruriens var. utilis showed the least response in both years. After one growing season M. pruriens var. utilis, M. cochinchinensis, and M. pruriens var. IRZ reduced speargrass shoot density by 50, 76, and 68%, and shoot dry matter by 72, 92, and 79%, respectively. Fertilizer reduced speargrass growth in velvetbean plots, while the opposite occurred in plots without velvetbean. Velvetbean residue effectively suppressed speargrass until the beginning of the subsequent cropping season. Maize grown 1 year after velvetbean required 50% less weeding than plots without velvetbean. Maize shade reduced speargrass shoot growth by 30-80% but regrowth of the weed occurred 4 weeks before maize harvest. Maize grain yield was higher in plots previously seeded to velvetbean than in plots without velvetbean. Speargrass shoot density and dry matter were negatively correlated with maize grain yield (r =-0.42 and r =-0.32, respectively, P < 0.01). Although velvetbean may effectively reduce speargrass during the year of establishment and the subsequent cropping phase it has a limited effect on rhizomes and, as such, does not provide a long term control