Adjustment of planting geometry along with suitable maize cultivar can be a viable tool for maximizing land usage and net return. A two-year study was carried out at Serw Agricultural Experiments and Research Station, A.R.C., Domiate governorate, Egypt, during 2015 and 2016 seasons to evaluate intercropping cowpea with suitable maize cultivar and its planting geometry for maximizing land usage and net return. The treatments were the combinations between three maize cultivars (SC 30K08, TWC 310 and TWC 352) and three maize plant distributions (one plant/hill distanced at 25, 50 and 75 cm between hills, respectively). Ridge width with maize plant distribution formed maize planting geometry (25 cm × 140 cm, 50 cm × 140 cm and 75 cm × 140 cm). These treatments were compared in a split plot distribution in randomized complete block design with three replications. Maize cultivar SC 30K08 had the highest grain yield and its attributes compared with the other cultivars in both seasons. Also, maize planting geometry 25 cm × 140 cm resulted in the highest grain yield and its attributes compared with the other planting geometries in both seasons. Ear length, ear weight, 100-grain weight and grain yield/fad were affected significantly by maize cultivars × maize planting geometry. Intercropping cowpea with maize cultivar TWC 352 had the highest seed yield and its attributes compared with those intercropped with the other cultivars in both seasons. Also, maize planting geometry 75 cm × 140 cm resulted in the highest seed yield and its attributes through growing two cowpea rows between maize hills compared with the other maize planting geometries in both seasons. Number of pods/plant and seed yield/fad were affected significantly by maize cultivars × maize planting geometry. LER and LEC values of the intercrops were much greater than 1.00 and 0.25, respectively, for all the combinations indicating less land requirements of intercropping system than solid culture of both crops. Growing one row of maize cultivar TWC352 in both sides of bed 140 cm width with cowpea two rows in middle of the bed increased land productivity and net return compared with solid culture of maize.
FAO (2013) Statistical Yearbook—World Food and Agriculture. FAO, Rome.
Bulletin of Statistical Cost Production and Net Return (2018) Summer and Nili Field Crops and Vegetables and Fruit, Agriculture Statistics and Economic Sector, Ministry of Egyptian Agriculture and Land Reclamation, Part (2), August 2018.
Ofori, F. and Stern, W.R. (1987) Cereal-Legume Intercropping Systems. Advances in Agronomy, 41, 41-90. https://doi.org/10.1016/S0065-2113(08)60802-0
Sanginga, N., Ibewiro, B., Hougnandan, P., Vantauwe, B. and Okogun, J.K. (1996) Evaluation of Symbiotic Properties and Nitrogen Econtribution of Mucuna to Maize Growth in the Derived Savannas of West Africa. Plant and Soil, 179, 119-129. https://doi.org/10.1007/BF00011649
Kumar, K. and Goh, K.M. (2000) Crop Residues and Management Practices: Effects on Soil Quality, Soil Nitrogen Dynamics, Crop Yield, and Nitrogen Recovery. Advances in Agronomy, 68, 197-319. https://doi.org/10.1016/S0065-2113(08)60846-9
Palm, C.A., Giller, K.E., Mafongoya, P.L. and Swift, M.J. (2001) Management of Organic Matter in the Tropics: Translating Theory into Practice. Nutrient Cycling in Agroecosystem, 61, 63-75. https://doi.org/10.1023/A:1013318210809
Futuless, K.N. and Bake, I.D. (2010) Evaluation of Yield and Yield Attributes of Some Cowpeas (Vigna unguiculata (L) Walp) Varieties in Northern Guinea Savannah. Journal of American Science, 6, 671-674.
Pappa, V.A., Rees, B., Walker, R.L. and Watson, C. (2011) Intercropping of Legumes and Cereals: Effect on Yield and N Uptake in a Three Year Low Input Crop Rotation. https://www.researchgate.net/publication/232808357_Intercropping_of_legumes_ and_cereals_effect_on_yield_and_N_uptake_in_a_three_year_low_input_crop_rotation
Abo-Shetaia, A.M., Abd El-Gawad, A.A., Mohamed, A.A. and Abdel-Wahab, T.I. (2002) Yield Dynamics in Four Yellow Maize (Zea mays L.) Hybrids. Arab Universities Journal of Agricultural Sciences (AJS), 10, 205-219.
Ihsan, H., Khalil, I.H., Reman, H. and Iqbal, M. (2005) Genotypic Variability for Morphological Traits among Exotic Maize Hybrids. Sarhad Journal of Agriculture, 21, 599-602.
Long, S.P., Ainsworth, E.A., Leakey, A.D.B., Nosberger, J. and Ort, D.R. (2006) Food for Thought: Lower-Than-Expected Crop Yield Stimulation with Rising CO2 Concentrations. Sciences, 312, 1918-1921. https://doi.org/10.1126/science.1114722
Storck, L., Lopes, S.J., Filho, A.C., Martini, L.F.D. and Pisaroglo de Carvalho, M. (2007) Sample Size for Single, Double and Three-Way Hybrid Corn Ear Traits. Scientia Agricola, 64, 30-35. https://doi.org/10.1590/S0103-90162007000100005
Lamlom, M.M., Abdel-Wahab, Sh.I., Abdel-Wahab, T.I. and Gendy, E.K. (2015) Chemical and Biological Influences of Some Preceded Winter Field Crops on Productivity of Intercropped Three Maize Cultivars with Soybean. Donnish Journal of Agricultural Research, 2, 55-65.
Zhao, S.L., Li, F.M., Zhang, D.Y. and Duan, S.S. (1997) Crop Production Is a Population Progress. Acta Ecologica Sinica, 17, 100-104. (In Chinese with English abstract)
Awan, A.R. (2013) Crop Geometry. Agrinfobank Blog Team. http://agrinfobank.blogspot.com/2013/11/crop-geometry.html
Mattera, J., Romero, L.A., Cuatrín, A.L., Cornaglia, P.S. and Grimoldi, A.A. (2013) Yield Components, Light Interception and Radiation Use Efficiency of Lucerne (Medicago sativa L.) in Response to Row Spacing. European Journal of Agronomy, 45, 87-95. https://doi.org/10.1016/j.eja.2012.10.008
El-Shamy, M.A., Abdel-Wahab, T.I., Abdel-Wahab, Sh.I. and Ragheb, S.B. (2015) Advantages of Intercropping Soybean with Maize under Two Maize Plant Distributions and Three Mineral Nitrogen Fertilizer Rates. Advances in BioScience and BioEngineering, 3, 30-48. https://doi.org/10.11648/j.abb.20150304.11
Mead, R. and Willey, R.W. (1980) The Concept of a “Land Equivalent Ratio” and Advantages in Yields from Intercropping. Experimental Agriculture, 16, 217-228. https://doi.org/10.1017/S0014479700010978
Adetiloye, P.O., Ezedinma, F.O.C. and Okigbo, B.N. (1983) A Land Equivalent Coefficient Concept for the Evaluation of Competitive and Productive Interactions on Simple Complex Mixtures. Ecological Modelling, 19, 27-39. https://doi.org/10.1016/0304-3800(83)90068-6
Freed, R.D. (1991) MSTATC Microcomputer Statistical Program. Michigan State University, East Lansing, Michigan.
Gomez, K.A. and Gomez, A.A. (1984) Statistical Procedures for Agricultural Research. 2nd Edition, John Willey and Sons, Toronto.
Chang, J.H. (1974) Radiation Balance. Climatic and Agriculture. An Ecological Survey. Aldine Publishing Company, Chicago, 4-22.
Paudel, M.M. (2009) Evaluation of Hybrid and OPV Maize Varieties for Grain Yield and Agronomic Attributes under Farmer’s Field Conditions at Dukuchhap. Nepal Agriculture Research Journal, 9, 17-20.
Shafi, M., Bakht, J., Ali, S., Khan, H., Khan, M.A. and Sharif, M. (2012) Effect of Planting Density on Phenology, Growth and Yield of Maize (Zea mays L.). Pakistan Journal of Botany, 44, 691-696.
Wade, L.J., Norris, C.P. and Walsh, P.A. (1988) Effects of Suboptimal Plant Density and Non-Uniformity in Plant Spacing on Grain Yield of Rain-Grown Sunflower. Australian Journal of Experimental Agriculture, 28, 617-622. https://doi.org/10.1071/EA9880617
Wade, L.J. and Douglas, A.C.L. (1990) Effect of Plant Density on Grain Yield and Yield Stability of Sorghum Hybrids Differing in Maturity. Australian Journal of Experimental Agriculture, 30, 257-264. https://doi.org/10.1071/EA9900257
Valentinuz, O.R. and Tollenaar, M. (2006) Effect of Genotype, Nitrogen, Plant Density and Row Spacing on the Area-Per-Leaf Profile in Maize. Agronomy Journal, 98, 94-99. https://doi.org/10.2134/agronj2005.0111
Idoko, J.A., Kalu, B.A. and Osang, P.O. (2018) Influence of Maize Varieties and Date of Planting Cowpea into Maize/Cowpea Intercropping System in Makurdi, Southern Guinea Savannah, Nigeria. International Journal of Sciences: Basic and Applied Research, 38, 98-113.
Summerfield, R.J., Huxley, P.A., Dart, P.J. and Hughes, A.P. (1976) Some Effects of Environmental Stress on Seed Yield of Cowpea (Vigna unguiculata (L.) walp.) cv. Prima. Plant and Soil, 44, 527-546. https://doi.org/10.1007/BF00011373
Eskandari, H. and Ghanbari, A. (2009) Intercropping of Maize (Zea mays) and Cowpea (Vigna sinensis) as Whole-Crop Forage: Effect of Different Planting Pattern on Total Dry Matter Production and Maize Forage Quality. Notulae Botanicae Horti Agrobotanici Cluj-Napoca, 37, 152-155.
Qasem, J.R. and Biftu, K.N. (2010) Growth Analysis and Responses of Cowpea [Vigna sinensis (L.) Savi Ex Hassk.] and Redroot Pigweed (Amaranthus retroflexus L.), Grown in Pure and Mixed Stands, to Density and Water Stresses. The Open Horticulture Journal, 3, 21-30.
Fujita, K. and Ofosu-Budu, K.G. (1996) Significance of Intercropping in Cropping Systems. In: Ito, O., Johansen, C., Adu-Gyamfi, J.J., Katayama, K., Kumar, J.V.D.K. and Rego, T.J., Eds., Dynamics of Roots and Nitrogen in Cropping Systems of The Semi-Arid Tropics, Japan International Research Center for Agricultural Sciences, Ohwashi, Int. Agric. Series No. 3, 19-40.
Rerkasem, B., Rerkasem, K., Peoples, M.B., Herrigde, B.F. and Bergersen, F.J. (1998) Measurement of N2 Fixation in Maize Rice Bean Intercrops. Plant and Soil, 108, 125-135. https://doi.org/10.1007/BF02370107
Vandermeer, J.H. (1989) The Ecology of Intercropping. Cambridge Univ. Press, New York. https://doi.org/10.1017/CBO9780511623523
Kropff, M.J. and Lotz, L.A.P. (1992) Systems Approach to Quantify Crop-Weed Interactions and Their Application to Weed Management. Agricultural Systems, 40, 265-282. https://doi.org/10.1016/0308-521X(92)90024-I
Chu, G.X., Shen, Q.R. and Cao, J.L. (2004) Nitrogen Fixation and N Transfer from Peanut to Rice Cultivated in Aerobic Soil in Intercropping System and Its Effect on Soil N-Fertility. Plant Soil, 263, 17-27. https://doi.org/10.1023/B:PLSO.0000047722.49160.9e