Objective:
To evaluate the performance of Kernza varieties with different planting dates
Personnel:
J.A. Torrion, Eeusha Nafi, Daniel Porter, Jacob Junger
Summary:
Kernza is perennial intermediate wheatgrass known for its extensive root system that uses nutrients more efficiently than wheat. This is the second year of the first Kernza trial conducted at the research center. Four Kernza entries (C3, C4, Clearwater, and Rush) were planted in the fall of 2019 on three planting dates (20-Sept., 27-Sept., and 04-Oct.) through the spring of 2020 on two planting dates (17-Apr. and 01-May).
Kernza was planted at a seeding rate of 4 live seeds/ft2 at 0.5-inch depth with 3.28-ft row spacing. During the second year of establishment (2021), we found no differences in biomass for all planting dates (Figure 1a). This is because, kernza planted during the spring of 2020 had already met its cold exposure requirement to produce heads (vernalized the following winter). During the first year (2020) biomass data, the earliest planted (Sept 20, 2019) kernza had the highest yield whereas the spring-planted had the least. For the two-year total biomass, the earliest-planted kernza generated the highest biomass whereas the rest of the planting dates had similar biomass (Figure 1b). As with the varieties, they performed similarly (Figure 2).
During the second year of establishment (2021), there was no significant effect among planting dates for grain yield. All planting date treatments averaged to 745 lbs/A grain yield. The significant differences in yield and biomass with planting dates were only observed during the first year of establishment (see the previous year's report). As for the varietal effects, Rush had the lowest yield. Clearwater, C4, and C3 had similar yields with each other and had significantly greater yields than Rush.
Table 1. Management Information |
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| Seeding date: | varied | Field Location: | X5 |
| Julian date: | varied | Harvest date: | 8/24 - 8/30 |
| Seeding rate: | 45 seeds/3.27 ft row. | Julian date: | 236 - 242 |
| Previous crop: | Canola | Soil type: | Silty loam |
| Herbicide: | 5/5/2020 Beyond 6 oz/A 5/6/2021 CleansweepM 1pt/A 6/17/2021 E-shredder 1 pt/A | Tillage: | Conventional |
| Insecticide: | None | Soil residual nutrient (NO3-, P, K lb/A): | 59-16-260 |
| Fungicide: | None | Nutrient fertilizer applied (N, P2O5, K2O lb/A): | 45-80-0 (10 S) (Fall, 2019) 75-0-0 (Spring 2021) |
Figure 1. Biomass a) 2021 yield with planting dates and b) the total two-year (2020 & 2021) biomass.
Figure 2. Kernza variety biomass performance in a) 2021 and b) total two-year (2020 & 2021) biomass. P value ns (not significant)