Funded by Results Driven Agriculture Research (RDAR)
When placed in the soil, seeds face a lot of challenges from diseases to pests to environmental stresses. While seeds can overcome some of these challenges on their own, the chances of success can be improved with seed treatments which is a way to support the growth of seeds and reduce the challenges they face. Inoculation of pulse seeds with various chemical and biological seed treatments such as rhizobia inoculation, bio-stimulants, and chemical fertilizers before or during seeding can therefore give the young seedling a good head start in its growth. This project sought to demonstrate the importance of various chemical and biological seed treatments on pea crop growth, production and soil nitrogen (N) levels.
What we did
The trial was conducted at the Debolt site in the MD of Greenview. The previous crop at the site was canola. Before seeding, the site was harrowed.
The trial was set up as a randomized complete block design with 4 replications of the following 10 seed treatments on the Amarillo pea variety:
Peas alone (PCon)
Peas+seed treatment (PST)
Peas+seed treatment+30 lbs phosphorus/acre (PST30P)
Peas+seed treatment+30 lbs phosphorus/acre + rhizobia inoculation (PST30PR)
Peas+seed treatment+60 lbs phosphorus/acre (PST60P)
Peas+rhizobia inoculation (PR)
Peas+60 lbs phosphorus/acre (P60P)
Peas+bio-stimulants (PBioS)
Peas+rhizobia inoculation+bio-stimulants (PRBioS)
Peas+rhizobia inoculation+60 lbs phosphorus/acre (PR60P)
Other management practices carried out on plots were:
The seeding date was May 30, 2022 with a 6-row Fabro plot drill equipped with disc-type openers on 9” row spacing and a mid-row bander for fertilizer.
Six rows that were 8m were seeded per plot.
Average soil temperature and moisture at 4" soil depth were 14.5°C and 19.2% volumetric moisture content (VMC), respectively.
Seeding depth was 1.0".
Peas were seeded at a full seeding rate of 180 lbs/acre
For treatments PST30P and PST30PR, the fertilizer drill was calibrated to deliver 59 lbs P/acre of 11-52-0 while for PST60P, P60P and PR60P, the drill was calibrated to deliver 118 lbs P/acre of 11-52-0.
Pea treatments with rhizobia inoculation were inoculated with Nodulator Duo SCG® granular inoculant at a rate of 3.7 lbs/acre.
Pre-emergent herbicide application was with StartUp a day after seeding. In-crop weed control measures were done with Basagran Forte herbicide on June 20, 2022.
Combine harvesting was done at full maturity stage on September 14, 2022.
What we found out
Results obtained through testing the various biological and chemical seed treatments on pea production and residual soil nitrogen, are shown in Table 32.
Plant emergence and normalized difference vegetative index (NDVI) readings ranged from 13 – 17 per sq m and 0.67 – 0.70 respectively and did not differ significantly amongst pea seed treatments.
Grain yield ranged from 11.8 – 17.0 bu/acre, bushel weight 57.3 – 59.0 lbs/bu and thousand kernel weight 203 – 210 g, and were not significantly different for all 9 seed treatments compared to the control.
Pea seed crude protein content was similar for the treatments and ranged from 22.3% – 23.2%.
Remarkably, most soil chemical parameters did not differ between the treatments and the control (data not shown). An exception to this was nitrate nitrogen (NO3N) for 2022, which showed higher values (9.5 ppm) for both PST60P and PR60P compared to control and other treatments (Table 33). The higher NO3N observed for both PST60P and PR60P may be due to some additional nitrogen from the monoammonium phosphate fertilizer applied at a higher rate of 60 lbs/acre.
Comments