Post Seeding Tasks
Dr. Tarlok Singh Sahota CCA
By the time you see this note, you would have completed seeding for this season. Immediate task
after seeding is to observe the crop emergence for gaps if any. If you find gaps try to find the
reasons; is it lack of adequate depth of seeding? Or is it trash that inhibited seed to go to proper
soil depth? Or do you find some wilting/or dead seedlings which most likely could be due to
seedling diseases (e.g. Rhizoctonia Solani in canola)/or even cutworms, especially in corn and
canola. Or do you find some plants cut and thrown to the ground, which would sure be due to
cutworms. Cutworm feeding may result in notched, wilted, dead or cut-off plants
(https://www.canolawatch.org/2020/05/27/insects-watch-flea-beetles-cutworms/). Patches of
missing plants could also be due to cutworms. Include cutworms on the scouting checklist for the
first one to three weeks after emergence. During the day, cutworms usually go back
underground. Therefore, scout late in the day or extremely early in the morning to look for
above-ground feeding cutworms. If cutworms are suspected but scouting is a challenge, consider
going out in the evening with the backpack sprayer and proper protective equipment to spray a
small area around the border of the patch. Check back in the morning to look for cutworms on
the soil surface. Spray threshold for cutworms in canola is 25-30 % stand reduction, whereas in
corn it is when 2-4% of plants are cut below the ground or 6-8% of plants are cut above the soil
surface, and cutworms less than 1 inch long present. Seedling diseases and insect pests would
lower the plant stand and impact crop yields. If you didn’t treat your seed with fungicides/or
insecticides (e.g. in canola for protection from flea beetle), make it a practice to treat seeds with
appropriate fungicides and insecticides next year(s). Spray threshold for flea beetle in canola is
when average leaf area loss reaches 25% or more. Chlorpyrifos (Trade name Lorsban) spray can
control both cutworms and flea beetles
(https://www.cropweb.com/assets/files/productdocuments/doc_9B59E78A6E202C6C7B20E243
B4AF1D2DE3422299.pdf) and several other insect pests. Flea beetle attack is more common in
warm and dry weather. In severe cases, more than one spray may be required. Keep a watch on
deadly swede midge attack on canola too. Its larvae eat and may kill the growing points. The
larvae feed protected by surrounding plant tissues, and damage symptoms may take a week or
more to develop (https://www.canolacouncil.org/canola-encyclopedia/insects/swede-midge/).
Use a hand lens to detect larvae and early damage symptoms, which can easily be mistaken for
heat or cold stress, fertility issues, mechanical damage, herbicide damage, drought or other insect
feeding.
Once the cereals had tillered well and canopy has covered the ground, its time to spray
fungicides (e.g. Stratego) to control foliar diseases that could lower leaf area index, weaken the
plants and stems and lower the grain and straw yields. Research at LUARS has shown that
spraying Manganese Sulphate @ 8 kg/ha in canola at 4-6 leaf stage could bring in seed and straw
yield benefits. If you applied less than 180 kg N/ha to canola at seeding, top dress the balance
amount of N at 4-5 leaf stage. Likewise for cereals; if you haven’t applied 80 kg N/ha at seeding,
apply the rest of the amount of N at tillering. Corn could be supplemented with required N
around knee high stage. Keep scouting your crops throughout the growing season to check for
any abnormalities/disorders and take appropriate remedial measures timely. Take help from the
Certified Crop Advisors, Researchers, Crop Consultants and OMAFRA Specialists in your area,
if need be. They will be all willing to help you.
May you have Bumper Crops!
