Producers know the importance of proper nutrient management for productive crop development. They also know that the right fertilizer in the right amount, place, and time, along with appropriate water management, should have minimal impact on the environment. Two graduate students in the UF/IFAS department of soil, water, and ecosystem sciences (SWES) took their research on this topic to the recent annual meeting of the Southern Branch of the American Society of Agronomy. Both were awarded third place in their respective divisions out of nearly 80 other students who were presenting research.

Potatoes

Ravinder Singh is a Ph.D. student whose research is titled “To evaluate the impact of biostimulant at variable nitrogen and phosphorus rates in potato production.” His study will address the challenge of low nitrogen use efficiency in sandy soils of northeast Florida. This leads to excessive nitrogen and phosphorus application and leaching into groundwater and nearby rivers. He hypothesized that adding biostimulant would provide additional nitrogen by fixing atmospheric nitrogen and enhancing phosphorus solubility in the soil.

Explaining the significance of his work, Singh stated, “If the biostimulant can reduce the amount of chemical nitrogen and phosphorus needed, then that not only saves the farmer money but also proves beneficial for the environment.”

The biostimulant did not exhibit a significant impact on tuber yield at any nitrogen rate. However, its application did lead to a noteworthy increase in total nitrogen uptake and nitrogen use efficiency at one of the two sites. Additionally, in-season nitrate levels at that site showed a decrease.
Reflecting on these findings, Singh commented, “I think this is a good start. More research is needed, specifically more soil biological analysis and better consideration of the biostimulant application rate and timing.”

Singh emphasized that the relatively low cost of the biostimulant ($13/acre) would be offset by the increased yield of highly marketable potatoes in northeast Florida. Additionally, a reduction in nitrate leaching would contribute to improved water quality in the region.

Looking ahead, Ravinder is replicating the experiment this year. He is further refining his study on the impact of biostimulants at variable nitrogen and phosphorus rates. Beyond this, Singh is exploring the efficacy of various environmentally smart fertilizers and bio-additives. The goal is to enhance nitrogen use efficiency and conserving Florida’s vital water resources. Singh is particularly notable for integrating advanced technologies into his research. He employs hyperspectral imagery and satellite data alongside artificial intelligence to develop a yield prediction model specifically tailored for potatoes. This innovative approach will enable the adjustment of in-season nitrogen application rates based on real-time assessments of the potato plants. That should optimize resource utilization and minimize environmental impact.

In addition to these ongoing efforts, it’s worth highlighting Singh’s past achievements. Ravinder earned awards for his oral presentations at the last year’s ASA CSSA SSSA International Annual Meeting held in Saint Louis, MO. He secured first place in the nutrient management session and second place in the sensor-based nutrient management session. Singh’s comprehensive and innovative approach underscores his commitment to advancing sustainable agricultural practices and contributing significantly to the field.

Corn

Master of Science student Sukhdeep Singh’s research is titled “Evaluation of Smart Fertilizer Technologies for Improving Nitrogen Use Efficiency in corn.” He looked at corn grown in sandy soil in the Suwannee River Valley of north Florida. The research focused on three smart fertilizer technologies (SFTs): biostimulants (BS), control release fertilizers (CRF), and nitrification inhibitors (NI). These SFTs were used with different nitrogen rates on farm plots at the North Florida Research and Education Center-Suwannee Valley.

“The overall goal was to see if any of the SFTs are effective at improving yield and nitrogen use efficiency in corn,” Sukhdeep Singh said. “We analyzed nitrate movement in the soil, the yield and nitrogen concentration data were collected at harvest, which was conducted at 147 days after planting.”

The results showed that the yield was significantly greater in all the treatments compared to the control. This also was true for nitrogen uptake, which also varied among the different SFT treatments. There also were significant differences among the treatment combinations (source + rate) as well as the different sources (BS, CRF, NI) for nitrogen use efficiency.

“First-year data shows that biostimulant coupled with the split application of nitrogen as urea improved the yield and nitrogen use efficiency compared to other treatment groups,” Sukhdeep Singh explained. He added that they need more research to draw more definitive conclusions. A second year of this trial will happen in 2024.

Apart from these continuing initiatives, it is important to recognize Sukhdeep’s prior successes. He secured third place in the nutrient management oral presentations at the 2024 ASA CSSA SSSA International Meeting.

Acknowledgments

Ravinder and Sukhdeep want to acknowledge their faculty advisor, Dr. Lakesh Sharma. Sharma is an assistant professor of soil fertility and sustainable nutrient management at SWES. He also is a project leader in the UF/IFAS Nutrient Management Program. The Florida Department of Environmental Protection (DEP) provided funding for both students’ research.

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