RESPONSE OF MAIZE TO PLANTING DENSITIES AND INCORPORATION METHODS OF PRECEDING COWPEA GREEN MANURE IN A DERIVED SAVANNAH ECOLOGY OF NIGERIA
A field trial was conducted in the University of Agriculture, Abeokuta, a derived savannah ecological zone of Nigeria, between April to September, 2009 and March to August, 2010 to evaluate the response of succeeding maize to planting density and application methods of preceding cowpea green manure.Â The green manure was established in a 2 Ã— 3 factorial experiment arranged in a Randomized Complete Block design RCBD. There were three populations densities/ha of cowpea: 30cmÃ—60cm(55,555), 30cmÃ—30cm(111,111) and 30cmÃ—15cm(222,222) and either incorporated or left as mulched six weeks after planting. One week after, maize variety, SUWAN1-SR was planted on all plots and a control plot. Biomass from population densities of 111,111 and 222,222 were similar (p>0.05) and higher (p<0.05) than that obtained from 55,555 in 2009. In 2010, different population produced significantly different biomass from each other, with biomass from 222,222 plants/ha being 52% greater than that from 111,111 plants/ha which was also 84% greater than from 55,555 plants/ha. Grain yield of maize from all incorporated green manure treatments were similar (p>0.05) and significantly higher (p<0.05) than from all mulched applied manure and control treatments in 2009. In 2010 maize grain yield was not significantly different across all treatments and control plots (p>0.05); highest grain yield (p>0.05) were obtained from treatments with both incorporated and mulched cowpea at 222,222 plants/ha. Grain yield of maize from all green manure plots were also higher (p>0.05) than the control plots. It was concluded that 111,111 plants/ha of Oloyin was the optimum for biomass production at 6 weeks after planting, for green manuring. Incorporating preceding cowpea green manure increased grain yield of succeeding maize. Growing cowpea at higher population density cannot make up for the losses of nutrient that would occur if the green manure is not incorporated.
Burie, M.L. 1992. Legume green manure: Dry season survival and the effect on succeeding maize crops. Soil management CRSP Tech. Bulletin, 92-04.
Carsky, R.J., Tarawali, S.A., Becker, M., Chikoye, D., Tian, G., Sangiga, N. 1998. Mucuna-herbaceuos cover legume with potential for multiple uses. Resource and Crop Management Research Monograph 25. IITA, Nigeria pp 52.
Canadian organic growers (COG). 1992. Field crop handbook: 1.5 Green manures. firstname.lastname@example.org
Hossner, L.R, Juo, S.R.O. 1999. Soil nutrient management for sustained food crop production in upland farming systems in the tropics. Food and fertilizer technology centre publication, 17p.
Hoyt, G.D. 1987. Legumes as a green manure in conservation tillage. In: J.F. Powers (ed.). The Role of Legumes in Conservation Tillage Systems. Soil Conservation Society of America, Ankey, IA. P. 96-98.
International Institute for Tropical Agriculture (IITA). Growing cowpea in Nigeria: Commercial crop production guide series. Pg. 1-7. Information and communication support for agricultural growth in Nigeria www.ics-nigeria.org.
Ismaila U., A. S. Gana, N. M. Tswanya, D. Dogara. 2010 Cereals production in Nigeria: Problems, constraints and opportunities for betterment, African Journal of Agricultural Research, 5(12): 1341-1350.
Lal, R.1983. Soil erosion in the humid tropics with particular reference to agricultural land development and soil management in Hydrology of humid tropical regions with particular reference to the hydrological effects of agriculture and forestry practice (Proceedings of the Hamburg Symposium, August 1983). IAHS'Publ. No. 140.
Lathwell, D.J. 1990. Legume green manure: Principles of management based on recent research. Trop. soils Technical Bulletin, 90-01.
Odhiambo, J.J.O., Ogola., J. B. O., Madzivhandila., T. 2010. Effect of green manure legume - maize rotation on maize grain yield and weed infestation levels. African Journal of Agricultural Research, 5(8): 618-625.
Ozowa, V.N. 1995 Information needs of small scale farmers in Africa: The Nigerian example. Quarterly Bulletin of the International association of agricultural information specialist, IAALD/CABI 40(1).
Sanchez, P.A., Palm, C.A., Szott, L.T., Curvas, E., Lal, R.1989. Organic input management in tropical agro ecosystems, p.125-152. In: Dynamics of soil organic matter in tropical ecosystems, D.C. Coleman et al. (Eds), NIfTAL Project, Univ. of Hawaii, Honolulu.
Squire, G.R. 1993. The physiology of tropical crop production. C. A. B. International for the overseas development administration. C. A. B. International, Wallingford, Oxon, U.K.
Sullivan, P. 2003. Overview of cover crops and green manures: Fundamentals of sustainable Agriculture. ATTRA publications, 16p.
Whitbread, A., Lawrence, J. 2006. Cowpea fact sheet for Grain and Graze. CSIRO Sustainable Ecosystems, 4p.