Blog Archives
JenREES 3/5/23
Well, March is here, and we start looking towards the next growing season. It was a great winter programming season, though, and it was great seeing many people!
Nontraditional Products: There’s a number of products on the market with claims of the biology or chemistry within them allowing for reduced nutrient inputs by the producer. The goal is for the biology or chemistry to make unavailable nutrients more available to the plant. Interest in the products stems from the potential to reduce nutrient inputs and enhance environmental stewardship, both of which would be beneficial. Perhaps the more recognized products currently are Pivot Bio PROVEN® and PROVEN®40? These products contain an N-fixing bacterial inoculant that is expected to fix N over the growing season. Use of biological N fixation in cereal crops has potential to reduce the use of synthetic N fertilizer, thus increasing N use efficiency and reducing N losses. We have 11 site-years of on-farm research data on the Pivot Bio products in 2021-2022. We have minimal testing on other biological/chemical products for reducing nitrogen rates. Pivot Bio was applied at 12.8 oz/ac and compared to an untreated check. The nitrogen rates were selected by the growers. Some growers chose the same N rate for both treatments, while others chose to evaluate Pivot Bio at additional reduced rates. It’s helpful to see comparisons at a range of reduced nitrogen rates to better determine nitrogen response to products tested.
Across 64 replications, the Check treatment yielded 234 bu/ac on average and Pivot Bio yielded 235 bu/ac on average, with no statistical difference at a 90% confidence level. When looking across the 64 replications, Pivot Bio had a 5 bu/ac or greater yield increase 27% of the time, a 5 bu/ac yield reduction 17% of the time, and yield difference within +/- 5 bu/ac 56% of the time. When looking at many of the individual locations, the grower-chosen N rates most likely could have been reduced beyond 40 lb/ac. Future on-farm research will focus on testing Pivot Bio PROVEN®40 at a wider range of N rates across different soil textures and landscape positions. One way to test this is by creating prescriptions for N rate blocks for different areas of the field. If you’re interested in testing something like this for Pivot Bio or any other non-traditional product, please let me know.
There’s also interest from producers seeking a regenerative ag path to grow their own microbes for reducing inputs through the use of compost extracts and teas. Compost is built through different processes then microbes are extracted from the compost using water and air. The water/microbe solution is then applied to a field while the compost is added back into a pile to be reused. One compost option is via a Johnson-Su bioreactor which uses a static aerobic composting process. Another is aerobic composting via a Turned Compost process. In 2022, a Seward Co. producer chose to compare a Check treatment of 142 lb N/ac and reduce the nitrogen rates added to the biological products in his study by nearly 40 and 100 lb N/ac. His goal was to push the system to see how the biological products compared and to have low enough nitrogen rates to see what the biological products would do in releasing N. His treatments and yields were: Check (total 142 lb N/ac yielding 235 bu/ac); Johnson-Su Compost High (total 106 lb N/ac yielding 220 bu/ac); Johnson Su Compost Low (Total 48 lb N/ac yielding 167 bu/ac); Turned Compost High (Total 106 lb N/ac yielding 212 bu/ac); Turned Compost Low (Total 48 lb N/ac yielding 164 bu/ac); and Pivot Bio Proven®40 (total 106 lb N/ac yielding 195 bu/ac). The Check treatment yielded the greatest and statistically was not different than the Johnson-Su High and Turned Compost High at the 90% confidence level. The Check treatment was different from the Pivot Bio and the lower rates of the compost extracts. The Johnson-Su and Turned Compost were applied at 8 gal/ac extract in furrow at planting. This study was pivot irrigated in a silt loam soil where the previous crop was soybean. This study will continue on these same strips for three years. Please let me know if you’re interested in testing compost extracts as we seek to obtain more data around this topic.
One thing to consider with any type of biological treatment study is it’s helpful to conduct the study on the same areas of the field for multiple years to better determine any impacts over time. 2022 On-Farm research book at: https://onfarmresearch.unl.edu/.