Diagnosis of Early Emergence Issues
In this example the radicle was damaged by seedling diseases but note new growth on both the radicle and seminal roots. There are signs of sidewall compaction.
Leafing out underground due to soil crusting.
This seedling shows root decay issues. The soil color indicated that this soil is not very well drained.
Opening up the seed furrow with a square-bottom spade reveals exactly how deep the seed was planted.
This seed shows considerable seed rot. The field had some drainage issues. It also looks like the embryo may have some insect feeding, most likely seed corn maggot.
In this example, the grower noted uneven growth in this area of the field. Opening up the seed furrow revealed the insect culprit - white grub, active right next to the roots.
In this example:
- About every 30-40 feet in this field there were two consecutive plants in the row that were slow to emerge or not emerged at all.
- In general, plant uniformity was good but there were enough skips to cause concern.
- Soil conditions for these seedlings were good, with no sign of sidewall compaction. However the roots were not in good shape - notice the dark discoloration of the radicle root on the stunted plants.
- The two plants on the left were side by side in the field and looked like potential runts. This is a very common occurrence where disease and/or insect issues usually impact 2-3 plants together.
- The field was planted April 18th and was visited on May 31st. The seeds had been in the ground for over 30 days, far beyond the life of the fungicide.
- The plant on the right had a robust radicle and seminal roots, as was typical of most of the plants that had more timely emergence.
- This picture clearly shows the importance of the radicle and seminal roots in achieving uniform emergence. If anything happens to the radicle, the plant is set back and may lose the emergence race and become a runt.
- Using a spade to open the seed furrow helped reveal the emergence issues taking place below ground.
A small water bottle can be a useful tool to wash off the roots in order to examine them more closely.