Corn futures rose toward $5.1 per bushel, hitting a one-week high as concerns over delayed US harvesting and weak crop conditions supported prices. Only 23% of the US corn crop had been harvested by October 4, below the 27% five-year average and 26% expected by analysts, after heavy Midwest rainfall delayed fieldwork. The share of the crop rated good-to-excellent also fell to 54% from 57% a week earlier. Export demand remains relatively firm, with 2026/27 shipments running 4.4% above last year at a record pace for this point in the marketing year, despite weekly inspections falling to 1.368 million tones. Elsewhere, Brazil’s first corn crop was 38% planted, slightly behind 40% a year earlier. Geopolitical risks added support, as Russia-Ukraine tensions raised concerns over disruptions to Black Sea grain shipping. Traders now await Friday’s USDA report for updated production and yield estimates, with current forecasts at 178.5 bushels per acre and 15.8 billion bushels of output.