Trial Report Summary

Foliar Strategies to Generate Severe Iron Deficiency Chlorosis (IDC) in Small Plot Research Trials

Crop Type(s):
Forages, Oilseeds, Soybean
Centre(s):
PESAI
Year(s):
2021
Collaborators(s):

N49 Genetics (Kevin Baron Kevin.Baron@solumvalley.com)
PESAI (Nirmal Hari)
Murphy et al. (Keith Murphy)
Manitoba Agriculture (Dennis Lange)

Objective(s):
  1. To evaluate a method of forcing symptoms of iron deficiency chlorosis (IDC) in soybean research trials across the Interlake and Red River Valley regions on Manitoba.
  2. In addition, to directly compare the yield response of IDC resistant and IDC susceptible cultivars (grouped) in response to the applied forcing treatment. IDC is a major stress factor that severely reduces the yield potential of soybeans grown upon calcareous, high pH soils in Manitoba.
Project Findings:

Based upon the transient, mild symptoms of IDC stress noted at both Arborg and Balmoral field locations following seeding operations and spring rains, sites selected for the study were conducive to developing severe IDC symptoms. Moreover, the subset of varieties further displayed the intended differential in visible symptoms of chlorosis.
These observations suggest that to reliably screen soybean germplasm for IDC year over year there may be merits to execute related agronomic studies or variety evaluations on high risk soils in conjunction with irrigation infrastructure. Maintaining cool, wet and saturated soil conditions for extending periods in the spring (May to June) may be necessary to consistently generate severe IDC pressure. N49 Genetics is developing such irrigation capacity for the 2022 season. The outcomes of this field project further indicate that downstream IDC screening activities may concentrate on phenotyping germplasm in controlled environments versus field environments. Future efforts aimed at evaluating the yield performance of IDC resistant versus IDC susceptible germplasm may also require alternative experimental designs (e.g. higher replication, spatial analysis of yield data) to obtain high quality yield data.

Background:

The current project sought to assess alternative methods of evaluating iron deficiency chlorosis (IDC) in soybean field research trials and quantify the yield impacts of severe IDC on resistant and susceptible soybean varieties currently grow in Manitoba. However, the overall lack of precipitation at sites for the 2021 growing season limited upper end yield potential, and also hindered the development of moderate to severe levels of IDC stress at these same sites.

PDF:

Entire findings are available by downloading the report PDF.

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