Seed placement uniformity and failure to establish a uniform plant stand are critical problems associated with no-tillage production of maize ( Zea mays L.) following wheat ( Triticum aestivum). The objective of this research was to evaluate the effect of different downforces (680, 880, 1150 and 1400 N) on performance of disc furrow openers and determine the optimum downforce for modified precision seeder equipped with single or double disc-type openers. The study was conducted in two different field conditions (field I and field II). The soil of field I and II were clay-loam and loamy, respectively. Seed spacing uniformity, sowing depth uniformity, mean emergence time and percentage of emergence were determined. Sowing depth and seed spacing uniformity, mean emergence time and percentage of emergence of both furrow openers were increased as a result of increasing downforce for both fields. The downforce of modified conventional precision seeder should be greater than 880 N for more precise no-till sowing using with single and double disc furrow openers for clay-loam and loamy soils.
