Project Details:

Investigation of the causes of low nutrient concentrations in high-yielding soybean cultivars

Parent Project: Investigation of the causes of low nutrient concentrations in high-yielding soybean cultivars
Checkoff Organization:Alabama Soybean Producers
Categories:Breeding & genetics
Organization Project Code:
Project Year:2020
Lead Principal Investigator:Alvaro Sanz-Saez (Auburn University)
Co-Principal Investigators:
Audrey Gamble (Auburn University)
Jenn Koebernick (Auburn University)

Contributing Organizations

Funding Institutions

Information and Results

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Project Summary

Globally, soybean is the largest source of both animal protein and vegetable oil that provides a variety of nutrients (N, P, K) and essential elements (Fe, Zn, etc.) that are very important for animal and human nutrition. A recent meta-analysis study has demonstrated that newer, high-yielding soybean cultivars, show decrease of 18 and 13% in seed P and K concentrations compared to older soybean cultivars, respectively (Balboa et al., 2018). In addition, wheat and soybean studies have observed that although newer cultivars always show higher yield, the micronutrient concentration (Fe, Zn) in the grains is significantly decreased (Garvin et al., 2006; Fritschi, personal communication). A decrease in mineral nutrient (N, P, K) and essential element concentrations (Fe, Zn, etc.) can reduce animal and human nutrition capacity of soybean (Myers et al., 2014). The causes underlying lower nutrient concentrations in high-yielding soybean cultivars are still unknown. It is hypothesized that the increased biomass accumulation and conversion to seed in the high yielding cultivars might dilute seed nutrients like P, K, Fe, and Zn. In addition, it is also hypothesized that the nutrient uptake and transport to the shoots may be mediated by the strength of the transpiration stream that pulls the nutrients from the soil to the leaves and seeds; therefore, cultivars that display lower transpiration may results in a lower nutrient content in the seed. Another possibility is that newer soybean cultivars need higher soil nutrient availability to maintain high seed nutrient content than is needed to maximize yield.

Project Objectives

The objectives of this study are (1) to confirm in an experimental setting that newer cultivars have lower seed nutrient concentrations than older cultivars, (2) test if P and K application above the extension recommendations can increase yield and seed nutrient concentration.

Project Deliverables

Progress of Work

Final Project Results

Benefit to Soybean Farmers

This project will increase our understanding of the factors that are important to maintain a high nutritional value of soybean seeds with respect to mineral composition. If differences in seed mineral concentrations are observed due to the different transpiration or yield responses, we will plan further experiments in multiple locations to study if the addition of fertilizers containing micronutrients can increase mineral concentrations in the seeds; with the final goal of improving soybean production and quality.

Performance Metrics

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