Increased planting density combined with reduced nitrogen rate to achieve high yield in maize

Abstract

The combination effects of nitrogen (N) fertilizer and planting density on maize yield, N use efficiency and the characteristics of canopy radiation capture and radiation use efficiency are not well documented in the Huanghuaihai Plain region in China. A 2-year field experiment was conducted from 2017 to 2018 in a split plot design with two N levels (240 and 204 kg N ha−1) applied to main plots and three plant densities (67,500, 77,625 and 87,750 plants ha−1) allocated to sub plots. Our results show that a 30% greater plant density combined with a 15% lower N rate (basal N) enhanced N partial factor productivity (NPFP) by 24.7% and maize grain yield by 6.6% compared with those of the conventional high N rate combined with a low density planting management practice. The yield increase was mainly attributed to significantly increased kernel numbers and biomass. The increased intercepted photosynthetically active radiation (IPAR) was the primary factor responsible for the high productivity of maize at increased planting density under reduced N conditions. The results indicate that increase planting density with reduced basal N application might benefit maize cropping for achieving high yields and sustainable development of agriculture.

Optimum Planting Density Improves Resource Use Efficiency and Yield Stability of Rainfed Maize in Semiarid Climate

“…However, only a few studies have explored how changes in the absorption and utilization of radiation, nutrients, and water caused by increasing planting density improve crop growth, development, and grain yield. Planting density affects the absorption and utilization of radiation, water, and nutrients in plants by changing the canopy and/or root system architecture ( Hammer et al, 2009 ; Du et al, 2021 ). Increased planting density improves the intercepted photosynthetically active radiation (IPAR) by rapid canopy closure and increases the leaf area index (LAI) ( Teixeira et al, 2014 ; Hernández et al, 2020 ).…”

“…Increased planting density improves the intercepted photosynthetically active radiation (IPAR) by rapid canopy closure and increases the leaf area index (LAI) ( Teixeira et al, 2014 ; Hernández et al, 2020 ). It is well-known that biomass yield is the production of IPAR, which ultimately converts into yield, and maize grain yield is determined by the product of total biomass ( Du et al, 2021 ). Increasing planting density increases IPAR, but it also increases competition among plants for light, water, and nutrients ( Ciampitti and Vyn, 2011 ; Rossini et al, 2011 ), causing abiotic stress in plants, which is often visually apparent in maize via the reduction in leaf area, leaf chlorophyll content, and grain biomass ( Osakabe et al, 2014 ).…”

Effect of Different Spacing on the Growth and Yield of California Wonder Bell Pepper (Capsicum annuum) on Sandy Loam Soil in the Gambia

“…The lower plant population densities produced more vigorous crops than at higher population densities but this could not compensate for the small number of plants per unit area. According to Du et al [22] the use of low population densities is achieved by higher plant spacing but cumulative yield per hectare was higher at high population density under low plant spacing. Findings by Sharma & Kumar, [23] reported that plant spacing had significant variation in almost all the growth and yield components, the number of branches/plant, the number of fruits/plant, and yield/plant were increased with the increasing of plant spacing but…”

Breeding plant type for adaptation to high plant density in tropical maize—A step towards productivity enhancement

“…PH in maize, a polygenic trait, is under strong genetic control (Peiffer et al., 2014) and is highly heritable because of its reliable phenotyping (Hallauer & Miranda, 1988). Though a larger fraction of shaded leaves lead to a higher ineffective photosynthetic area and canopy respiratory consumption especially at a high LAI (Du et al., 2021), severe leaf loss (four or six uppermost leaves removed) imposed close to silking reduced N remobilization from stem and suppressed photosynthesis for poor N uptake, resulting in decreased N accumulation in kernels (Liu et al., 2020). Optimal leaf removal by excising the uppermost two leaves of corn plants grown under high‐density conditions in North China increased N accumulation in kernels at physiological maturity (Liu et al., 2020).…”