Early season, The Bean Report

The Bean Report – May 29, 2019

May 29, 2019

Listen to the Bean Report here:

 

Crop Update

  • Soybean seeding is almost complete across Manitoba. Early-seeded soybeans have just begun to emerge in the central region over the past week. Symptoms of both chilling injury and deep seeding have been found, including twisted and swollen hypocotyls.
    • Note: If the hypocotyl arch is just below the soil surface or soybeans have just emerged, wait until the V1 stage to roll.
  • Dry bean seeding continues in the central and southwest regions of Manitoba, sitting at approximately 45-50% complete.
  • Field peas and faba beans have emerged over the past week or two and are currently sitting at the V1 to V5 stages. See the new growth staging guides for field peas and faba beans!
  • Be on the lookout for frost damage in any emerged soybean and dry bean fields. Note that frost should be assessed on a field-by-field basis. The impact of frost depends on the severity and duration of freezing temperatures. Field peas and faba beans are tolerant to frost, as the growing point is located below ground. Click here for more information on assessing frost.

Worried about frost damage to your beans?

If soybeans and dry beans are still below ground, they are safe from frost. If emerged, the level of damage depends on the severity and duration of freezing temperatures.

In 2015, a spring frost event occurred on May 30. At Morden, this 3-hour frost (-0.5, -1.6 and -0.5°C) left some plants with significant damage to the growing point (left), reducing plant stand, while others experienced only minor damage (right). Plants with minor frost damage can develop new shoots from the axillary buds, producing a double-stemmed plant.

 

Scouting for early season insects and diseases

As pulse and soybean crops begin to emerge, watch for early season disease and insect pressure. Investigate any abnormality, including wilted, chlorotic or necrotic plants and patchy emergence.

Diseases:

  • Fusarium, Rhizoctonia solani and Pythium spp. in all pulses and soybeans
  • Phytopthora sojae in soybeans
  • Aphanomyces euteiches in peas

Insects:

  • Wireworms in all crops
  • Seedcorn maggot in soybeans and dry beans (+ other crops)
  • Cutworms* in all pulses and soybeans (+ other crops)
    *Cutworms have been reported in central MB this week.

Pea leaf weevil monitoring in Manitoba

Though pea leaf weevil has not been found in Manitoba yet, the best time to look for potential damage is at the end of May to early June. Pea leaf weevil feeding appears as leaf notching in field pea and faba bean plants.

View the current pea leaf weevil monitoring protocol here.

 

If you suspect pea leaf weevil in your field, please contact any of the following:

John Gavloski
Entomologist
Manitoba Agriculture
(204) 750-0594
John.Gavloski@gov.mb.ca 		Cassandra Tkachuk
Production Specialist (East)
MPSG
(204) 293-4424
cassandra@manitobapulse.ca		 Serena Klippenstein
Production Specialist (West)
MPSG
(204) 751-0219
serena@manitobapulse.ca

 

Assessing pea plant stands

Plant stand (population) assessment compares the number of live plants established per unit of area to the seeding rate to estimate seed survival. Reaching target plant stand can potentially:

  • Allow for better competitive ability of the crop
  • Allow the pea plants to knit their tendrils together, as they are all semi-leafless varieties
  • Increase yield or lower seed cost

Optimum target plant population for field peas is 350-400,000 plants/ac. Use the MPSG Bean App Plant Stand Assessor tool to calculate and compare plant populations in your field with the optimum target plant populations for pulses and soybeans.

 

Identifying weed seedlings

Proper identification of weed seedlings is an important part of early season weed control. A few weed seedlings to scout for right now are:

  • Biennial wormwood
  • Kochia
  • Volunteer canola
  • Yellow foxtail

For more information on weeds commonly found in Manitoba, click here.

 

Dry bean pre-plant/pre-emergent herbicide options

Questions? Contact MPSG’s production specialists for answers.

Cassandra Tkachuk
Production Specialist (East)
(204) 293-4424
cassandra@manitobapulse.ca		 Serena Klippenstein
Production Specialist (West)
(204) 751-0219
serena@manitobapulse.ca