Influence of NPK fertilizer on tuber yield of early and late-planted cassava in a forest alfisol of South-Western Nigeria

Four new cassava varieties ( NR 8082, TMS 00033, TMS 91/ 453 and TMS 00447) were fertilized with NPK ( 20-10-10) at the rates of 0, 200, 400, and 800 kg/ha in an experiment with the crop planted early (April) in 1999 and then late (September) in 2000. Tuber yield was 28% higher in early-planted cassava than in the late cultivation. Yield was reduced by 44% in NR8082, 15% in TMS 00033 and 45% in TMS 00447 as a result of late planting. Tuber yield from NR 8082 (44t /ha) was the highest for early-planting while TMS 00033 gave the highest yield (31 t/ha) in late planting. Fertilizer influence on tuber yield was not significant in early-planted cassava. In late-planted cassava, significant reduction in yields was observed from the application of 400 and 800kg/hectare of fertilizer. Incidence of tuber rot was influenced by varietal differences rather than fertilizer rates. Incidence of rot was lowest in NR8082 (9-10%) and TMS 00033 (10-11%) in both plantings and the severity was mild in all the varieties. TMS 00033, a low cyanide variety, have tuber yields above 30 t/ha in both early and late plantings and is therefore recommended for adoption trials by farmers. Key Words: Early and late planting, cassava varieties and tuber rot. African Journal of Biotechnology Vol.3(10) 2004: 547-55

Comparative study of storage methods of maize grains in South Western Nigeria

Laboratory experiment was conducted to assess the efficacy of different storage methods of maize grains in Ibadan (a humid tropical ecology) between year 2002 and 2003. The results shows that storage methods (SM), treatment (Tr), SM x Variety (V) and Tr x V interactions were highly significant for numbers of undamaged maize grains (

Evaluation of fallow and cover crops for nematode suppression in three agroecologies of south western Nigeria

A study was conducted in three agroecological zones of south-western Nigeria to evaluate the effect of siam weed (Chromolaena odorata) and mucuna (Mucuna utilis) cover/fallow crops on plant-parasitic nematode population. The natural bush regrowth was used as control. Plant-parasitic nematodes were identified and counted during the fallow periods. Eleven genera of nematodes were identified and three (Meloidogyne, Pratylenchus, and Helicotylenchus) species were predominant across the trial locations.Other important genera present were Scutellonema, Tylenchorhynchus and Rotylenchus species. Nematode population densities of pre-crop were lowest in Alagba soil (Rhodic lixisols) at Ikenne in the wet forest zone of Nigeria. The populations in Iwo soil (Rhodic haplustalf) at Ibadan, a dry forest zonewas lower than in the Temidire soil (Plinthic luvisol) at Ilora in the derived savannah of south-western Nigeria. There was significant suppression of nematode population densities under the different crops as the fallow period increased. The population reduction in the different locations depended on the nematode species and the cover crops. The natural bush re-growth had the least effect on the nematode suppression at the end of the fallow period. On the average, siam weed fallow reduced nematode population densities by 67-79%, mucuna by 64-72% and the natural bush by 30-49% across the trial locations. For effective nematode suppression with fallow cropping, proper determination of the principal nematode species predominant in an environment is essential

Effects of land quality, management and cropping systems on cassava production in southern western Nigeria

The study was carried out to assess the effects of land quality, management and cropping system on cassava production in the derived savanna and rain forest of southwestern Nigeria. Soil quality wasstudied from farmers’ fields which had been under cassava cultivation for at least ten (10) years. The yield data obtained from different crop mixtures and management practices were compared with theperformance of cassava. The results showed great diversity of soils suitable for cassava production but good management and cropping system determined the yield. Maximum yield (78.5 t.ha-1) of cassavawas recorded on fertile, sandy clay loam soil (Apomu series, Eutric Luvisol) intercropped with maize, followed with cowpea in relay cropping. Lowest yield (3.3 t.ha-1) was obtained on degraded low fertilitycompacted sandy soil of shante series (Albic Luvisol) under maize/cassava/crop mixture, with cashew. The results indicated that the more the use of appropriate agricultural input, management level and land requirement, the more the yield of cassava across the ecological zones studied