Row placement affects yield and water use efficiency of continuous corn

Abstract

The planting of crops in rows results in a large amount of variation in soil nutrient levels and soil water. The hypothesis of this paper is that row spacing can be adjusted to optimize water use efficiency (WUE). The objective was to investigate the effects of row placement on corn (Zea mays L.) growth, leaf photosynthetic characteristics, yield, soil water, inorganic nitrogen (N), evapotranspiration (ET), and WUE in the Corn Belt of Northeast China (CBNC). Corn was planted in either the intra‐row or inter‐row space of the previously planted corn in a 2‐yr (2017–2018) field experiment in Jilin Province, China. All corns were planted at a row spacing of 60 cm, a plant spacing of 28 cm, and a density of 60,000 plants ha−1 per year. The inter‐row corn treatment maintained higher leaf area index, net photosynthetic rate, and transpiration rate at the R3 growth stage in 2017 and 2018. The corn yields of inter‐row treatment were 6.0% and 8.5% higher (P ≤ .05) in 2017 and 2018, respectively, compared with intra‐row treatment. The ET in inter‐row treatment was 4.4% (P < 0.01) lower in 2017 and its 2‐yr WUE was 11.5% higher (P = 0.016) than that of intra‐row treatment. These findings suggest that corn rows should be arranged at the inter‐row of the previous corn in a continuous corn cropping field, and an intra‐row position of the previous crop should be considered in the definition of continuous monocropping for row‐planted crops.

Seed row placement relative to the previous crop stubble row can harness systems benefits on water repellent sands

“…The implementation of near-row sowing requires careful thought, both because of the requirement for additional investment in seeder set-up but also due to the potential for net negative effects in environments that are not water repellent. A recent example from corn grown in China showed a negative outcome for water use efficiency when sown on the previous crop row (Sun and Li 2020) while earlier work showed that sowing close to the previous row is a practice that can exacerbate Fusarium pseudograminearum (crown rot) root disease risk (Verrell et al 2017) but not Rhizoctonia solani AG8 (rhizoctonia) root rot (Davis et al 2008). The aim of this set of experiments was to evaluate the no-till systems benefits of near-row sowing treatments for soil water access in the furrow seed zone, crop establishment, crop competition with weeds, root disease infection and cereal crop grain yield in low-rainfall sandy soil environments.…”