SEED DISTRIBUTION IN SOIL AND ITS EFFECTS ON EARLY PLANT GROWTH

Seed distribution in soil has important implications for agronomic performance of crop and design and evaluation of seeding equipment. Measurements were performed in two fields. One field was seeded with pea crop using a side-band opener, and the other field was seeded with canola crop using a single-row opener and a paired-row opener. Positions of seed in soil were measured in three dimensions (along the crop row, lateral, and vertical directions). Early crop growth characteristics (plant height and plant dry weight) were also measured. Results showed that laterally seeds were spread as wide as 60 mm in the soil by the side-band opener, 94 mm by the single-row opener, and 250 mm by the paired-row opener. Horizontally, seeds were highly scattered, and the average absolute. seed spacing was 48, 50, and 75 mm for the side-band, single-row, and paired-row openers respectively. Vertically, the side-band opener placed pea seeds at an average depth of 39 mm (SD: 13 mm), and the single-row and paired-row openers placed canola seeds at an average depth of 21 mm (SD: 7 mm) and 18 mm (SD: 8 mm), respectively. Pea plants seeded at depths below 15 mm had smaller plant height and lower dry weight compared to those seeded at greater depths. Canola plants showed smaller height and lower dry weight when seeded shallower than 5 mm and deeper than 35 mm.