Planting Patterns and Radiation Interception, Plant Nutrient Concentration, and Yield in Corn

Abstract

AbstractThe upper leaves of corn (Zea mays L.) are radiation‐saturated while the lower leaves, the prime source of carbohydrates for nutrient uptake by roots, are radiation‐starved. This study was conducted to determine the degree to which planting patterns could influence radiation interception by layers in the canopy, plant nutrient concentration, and yield in corn. Corn was planted in the field in a high‐yielding environment on a Drummer silty clay loam (finesilty), mixed, mesic, Typic Haplaquoll) in 0.38 m single rows, 0.76 m twin rows, 0.76 m single rows, 1.14 m twin rows, and 1.52 m twin rows with 0.13 m between pairs of twin rows. Interception of solar radiation shortly after silking was generally similar for all the planting patterns except for the 1.52 m twin row spacing which intercepted 10% more incident radiation with lower rather than upper leaves compared to the other planting patterns 3 h before solar noon, but allowed 7% more incident radiation to strike the soil surface compared to the narrow row spacings (0.38 ‐ 0.76 m) at solar noon. Planting pattern had no consistent effect on nutrient concentration in the grain, stover, or cob. Grain yields averaged 9.7 Mg ha−1 for the 1.52 m twin planting pattern and 11.7 Mg ha−1 for the other planting patterns. In conclusion, wide row spacings resulted in a partial redistribution of radiation from the upper to the lower leaves but allowed more radiation to strike the soil surface, did not affect plant nutrient concentration, and decreased yield.