“The majority of problems are not due to a lack of technology, but rather a lack of proper adjustment and maintenance…”
Paulo Arbex is a specialist in plantability for major crops, a professor of agricultural machinery and mechanization at São Paulo State University (Unesp) and an agronomist with a master’s and Ph.D. from the institution.
AgriBrasilis – What is plantability and what is its importance?
Paulo Arbex – Plantability is the ability of the planter to position each seed at the correct depth for the crop, at the ideal spacing between seeds and at the recommended population.
Plantability is very important because, when done correctly, it ensures an increase in productivity. Poorly distributed seeds during planting result in dominated plants [plants that lose initial competition because another plant germinated earlier or was positioned more favorably in the furrow], skips, doubles, uneven growth stages and losses ranging from 8% to 12%, depending on the crop and stress conditions.
AgriBrasilis – What basic precautions should the farmer take before starting planting?
Paulo Arbex – Some basic precautions are:
- Analyze the soil (moisture, installed cover crop, leveling, soil structure, etc.).
- Check the quality of the seed lot (screen size, shape, purity, vigor).
- Inspect the planter: meters, discs, rings, openers, press wheels, gauge wheel.
- Adjust the machine in the field to be planted, not only in the shed.
- Confirm that the straw is properly dry to ensure clean cutting of the residue and to avoid clogging.
AgriBrasilis – What factors determine high-quality planting?
Paulo Arbex – A high-quality planting depends on five pillars:
- Longitudinal distribution (avoiding doubles and skips).
- Uniform depth — a 1 cm difference already changes the emergence pattern.
- Seed–soil contact — properly adjusted press wheels.
- Furrow environment: moisture, structure and presence/height of straw.
- Planting speed compatible with the meter and the condition of the machine.
If these factors are in balance, the crop emerges quickly, uniformly and vigorously.
AgriBrasilis – What are the most common mistakes that compromise plantability?
Paulo Arbex – The main error is excessive planting speed, which is considered the biggest villain in the process. Also common are problems such as using an inadequate disc size for the seed in mechanical meters, unleveled machines and the absence of preventive maintenance for essential components like rings, chains, clamps and springs.
Misadjusted compacting wheels can leave the furrow open or excessively compacted, which harms emergence. Finally, poorly adjusted seed treatments alter the material’s fluidity and when there is no corresponding correction in the planter, they compromise seed distribution.
AgriBrasilis – How does the correct seeder adjustment prevent these failures?
Paulo Arbex – The adequate planter adjustment is decisive for preventing plantability problems. When the equipment is correctly adjusted, the seed disc performs singulation accurately, preventing the occurrence of double seeds or skips (missed seeds) along the row. The correct adjustment of the springs maintains a uniform depth for seed deposition across all rows, ensuring homogeneous emergence conditions.
Similarly, well-adjusted compacting wheels ensure the perfect closing of the furrow, avoiding both excess and lack of compaction. The operating speed, when adjusted to the recommended limits, reduces vibrations and preserves the quality of the planter’s work. Taken together, these adjustments allow plants to emerge uniformly, competing on equal terms and resulting in higher productivity.
AgriBrasilis – What has the IPS (Seeding Plantability Index) Project shown about the state of seeders in Brazil?
Paulo Arbex – The IPS Project (Seeding Plantability Index) has revealed a concerning reality:
- More than 80% of the planters evaluated show some degree of misadjustment.
- In many regions, yield losses exceeding 10% occur due to preventable skips (missed seeds) and doubles.
- The majority of problems are not due to a lack of technology, but rather a lack of proper adjustment and maintenance.
- Small adjustments—such as changing rings, using the correct disc, proper row unit pressure and reducing speed—already significantly elevate the assertiveness level of the seeding process.
The IPS shows that the greatest tool for increasing productivity today is correct adjustment, not necessarily the replacement of the planter.