Abstract: Aims Row spacing is a cultivation technique used for many field crops , but not wheat, for which traditional row spacing of
20 cm is used regardless of spike-type wheat cultivar. Our objective was to examine the effects of row spacing on canopy
structure, its microclimate and yield in heavy-ear winter wheat, Triticum aestivum.
Methods We conducted a field experiment on the farm of National Engineering Research Center for Wheat, Zhengzhou, China,
using heavy-ear winter wheat cultivar `Lankao Aizao 8’. Three row spacing treatments (15, 20 and 30 cm) were used in a
randomized complete block arrangement with three replications.
Important findings Leaf area index decreased and canopy openness increased with increased row spacing. Moreover, light
interception at different layers, extinction coefficient, and relative humidity decreased, canopy temperature at each layer
increased, and the spread of carbon dioxide was unchanged. Yield could be in creased by reducing row spacing to have an even
plant-to-plant distribution that could weaken competition. Our finding that 15 cm row spacing was beneficial to canopy
structure and yield indicated that heavy-ear winter wheat cultivar ‘Lankao Aizao 8’should not be planted in conventional 20
cm row spacing.