Planting Density and Variety Modulated Root and Leaf Characteristics to Improve Grain Yield of Spring Maize

Abstract

To better understand the accumulation and transport of substances under different planting densities, the adaptation of maize root and leaf in response to increasing planting densities was investigated. In this two-year filed study, three maize varieties, Fumin108 (FM), Xianyu335 (XY) and Dika159 (DK), were sown under three different planting densities: 15,000 (D1), 60,000 (D2) and 90,000 plants ha-1 (D3) during 2018 and 2019. Increase in planting density gradually increased leaf area index along with reduced leaf area and net photosynthetic rate of individual leaves. In the 0–20 cm soil layer, the average root dry matter decreased by 55.88 and 80.92%, and the average root number decreased by 31.18 and 38.71% under D2 and D3, respectively, compared with D1. With increase in planting density, yield and dry matter per plant of maize gradually decreased while yield and dry matter per ha was increased with increase in D1-D2 density and then flattened in D2-D3 density. Compared with D1, two-year average yield per plant was decreased by 34.10 and 51.87% under D2 and D3, respectively. The difference in the number of roots of XY, FM and DK were not significant, so change in variety did not alleviate the decrease in the number of roots. At higher planting densities (above D2), the increase in density did not increase per ha grain yield. In conclusion, the suitable plant density was about 60,000 plants ha-1 to harvest more yield of spring maize while density higher than that reduced leaf area and photosynthesis per plant. Moreover, leaf area, root number and net photosynthesis per plant was higher in lower planting density coupled with overall less yield on ha basis and thus seemed wastage of soil nutrients and light resources. © 2021 Friends Science Publishers

Evaluation System of Intercropping Functional Food Sweet Corn and Vegetable Soybean in Different Planting Density and Compound Fertilizers Dosages

“…With a dosage of nitrogen fertilizer of 200 kg ha -1 and a corn plant density of 8.25 million, a maximum yield of 9321.21 kg ha -1 can be achieved [30]. Yang et al [19] reported that optimum plan density achieved high corn yield, if the density is increased, it will not increase yield of corn. Subaedah et al [6] also reported that the twin row system obtained highest maize yield.…”

“…In order to increase yields of spring maize, it was determined that a plant density of around 60,000 plants ha-1 was sufficient, however a density greater than that specified could diminish leaf area and photosynthesis. In addition, each plant's leaf area, number of roots, and net photosynthesis were greater in low-density crops, which also produced less yield per hectare and wasted soil resources and light sources [19]. Similarly, Promsomboon et al [20] showed that the highest output per Rai was 703 kg with 3 seedlings per hill, while the lowest yield was 496 kg with 1 seedling hill-1 (S-1).…”