By Scott Hartley, PAg, Manager, Crop Protection Laboratory, Regina
Sample submissions to the Crop Protection Lab have been constant in June, with more than 100 samples received so far in 2018.
More than 20 of the samples showed symptoms of root rot in pulse crops (primarily in pea and lentil but also noted in chickpea). Fusarium species were the most common pathogens, occurring in more than 50 per cent of the samples. An oomycete, such as Pythium or Aphanomyces were present in approximately 25 per cent of the samples.
Many of the earlier samples (13) showed environmental stress and damage. These symptoms were noted in field crops and coniferous trees. Earlier in June, heat stress and lack of moisture were the main factors.
Herbicide damage was evident in 19 samples. In most cases, these were problems with carryover due to dry conditions in 2017 that prevented the breakdown of certain herbicides in the soil. Effected crops include cereals, oilseeds and pulses in herbicide Groups 2, 4, 5, 14 and 27.
Deeper seeding to reach moisture or wind filling loose soil into seed rows was an issue in a few samples where the plants had expended their reserves to reach the surface, at which point they were weak and prone to other environmental stresses such as wind.
Insect samples have included Enchytraeids (small white worms similar to earthworms), barley thrips, spider mites in spruce trees and springtails (Collembola). Of special note, red bugs were submitted again this year, but, unlike 2017 where the insect was Peritrechus convivus causing damage to slow-growing canola seedlings, the insects this year have been soft-winged flower beetles (Collops sp.) and white-margined burrower bugs (Sehirus cinctus). Neither is considered significant pests of field crops; the latter preferred hosts include plants in the mint and nettle families.