Agronomic Response of Soybean Varieties to Plant Population in the Guinea Savannas of Nigeria

Abstract

e agronomic responses of three contrasting soybean [Glycine max (L.) Merr.] varieties to plant populations were examined in two distinct agro-ecological locations (at Samaru Zaria and Samaru-Kataf), both in the Guinea savanna of northern Nigeria in 2009, 2010, and in 2011 growing seasons. ree soybean varieties: TGx1835-10E, TGx1904-6F, and TGx1448-2E di ering in maturity duration (early, medium, and late maturing, respectively), were evaluated at four plant populations (266,700, 333,300, 533,300, and 666,700 plants ha -1 ) using a split plot arrangement in randomized complete block design with three replications. e plant populations were the main plots, whereas varieties were subplots. e proportion of intercepted photosynthetically active radiation (IPAR) and leaf area index (LAI) increased with increasing plant population at both locations, indicating that high leaf area indices and high degree of canopy closure at higher plant population intercepted more light than the canopy at lower population and subsequently resulted in relatively high grain and fodder yields. At both locations, optimum plant populations ranged from 533,300 to 666,700 plants ha -1 across the years. e northern Guinea savanna location (Samaru Zaria) produced more pods m -2 , grain yield, and fodder at higher plant populations than that at the southern Guinea savanna (Samaru-Kataf). Varieties TGx1448-2E and TGx1904-6F intercepted higher proportion of IPAR had higher LAI and produced a greater number of pods m -2 , seeds m -2 , grain yield, and fodder than TGx1835-10E at both locations in years of good rainfall. ese data suggest that soybean yields in the Guinea savanna of northern Nigeria can be increased using higher plant populations than those currently recommended.

Agronomic optimal plant density for semiupright cowpea as a second crop in southeastern Brazil

“…For each plant architecture, production system, and growth condition, it is essential to investigate the optimal combination between within-row plant spacing and row width to agronomically maximize seed yield. Efficiently optimizing plant arrangement strongly influences the input use efficiency and yield potential for each genotype (Bezerra et al, 2008;Bezerra, Távora, Freire-Filho, & Ribeiro, 2009;Kamara, Ewansiha, Boahen, & Tofa, 2014;Sadras, Thomas, Cozzolino, & Cossani, 2019;Soratto, Souza-Schlick, Fernandes, Zanotto, & Crusciol, 2012).…”

“…For semiupright cowpea cultivars, the row spacing mostly used is 45-50 cm (Bezerra et al, 2008(Bezerra et al, , 2009Matoso et al, 2018), with the plant density ranging from 9 to 11 plants m −1 (Cardoso & Melo, 2017). However, the withinrow plant density (sowing density), which will define the number of plants per unit area, is one of the factors that can interfere more strongly in crop yield (Bezerra et al, 2008(Bezerra et al, , 2009Kamara et al, 2014;Rondanini, Menendez, Gomez, Miralles, & Botto, 2017). Under low plant density, perplant yield increases although per-unit area yield is lower (Bezerra et al, 2008(Bezerra et al, , 2009Carciochi et al, 2019;Duncan, 1986;Kamara et al, 2014;Santos, 2013), especially if genotypes with less plasticity are used and in low-yielding environments (Bezerra et al, 2009;Carciochi et al, 2019;Rondanini et al, 2017).…”

“…However, the withinrow plant density (sowing density), which will define the number of plants per unit area, is one of the factors that can interfere more strongly in crop yield (Bezerra et al, 2008(Bezerra et al, , 2009Kamara et al, 2014;Rondanini, Menendez, Gomez, Miralles, & Botto, 2017). Under low plant density, perplant yield increases although per-unit area yield is lower (Bezerra et al, 2008(Bezerra et al, , 2009Carciochi et al, 2019;Duncan, 1986;Kamara et al, 2014;Santos, 2013), especially if genotypes with less plasticity are used and in low-yielding environments (Bezerra et al, 2009;Carciochi et al, 2019;Rondanini et al, 2017). By increasing plant density, perplant yield decreases but with an increase in per-unit area yield (Bezerra et al, 2008(Bezerra et al, , 2009Kamara et al, 2014;Li et al, 2020).…”

“…Under low plant density, perplant yield increases although per-unit area yield is lower (Bezerra et al, 2008(Bezerra et al, , 2009Carciochi et al, 2019;Duncan, 1986;Kamara et al, 2014;Santos, 2013), especially if genotypes with less plasticity are used and in low-yielding environments (Bezerra et al, 2009;Carciochi et al, 2019;Rondanini et al, 2017). By increasing plant density, perplant yield decreases but with an increase in per-unit area yield (Bezerra et al, 2008(Bezerra et al, , 2009Kamara et al, 2014;Li et al, 2020). Competition at high intensity in early stages of crop development can favor the emergence of unproductive plants and cause a decrease in the final productive stand and yield (Bezerra et al, 2008;Soratto et al, 2012) as well as increases the risk of lodging and impairing mechanized harvest procedures (Carciochi et al, 2019;Farias et al, 2019).…”

From targeting to tailoring : baskets of options for legume cultivation among African smallholders

“…The seed was sown by individual farmers immediately afterwards. Recommendations included to plant soybean on top of ridges at a spacing of 75 cm between rows and 10 cm between plants with 3 seeds per hill (Kamara et al, 2014). However, reported densities varied from 75 to 90 cm between rows and 5 to 25 cm between plants.…”