Water and Nutrient Footprint of Pulse Crops

"Minimizing Water and Nutrient Footprint for Sustainable Pulses-Wheat Cropping Systems and Enhanced Soil Health"

USDA-ARS Pulse Crop Health Initiative Research Project 

Principal Investigator:

Olga Walsh

Collaborators:

Kurtis Schroeder

Patrick Hatzenbuehler

Graduate student, MS Plant Science:

Francisco Bautista

Summary: The unprecedented multi-year drought currently experienced throughout most of the US is especially severely impacting dryland and semi-arid/arid crop production areas in Idaho vitally dependent of supplemental irrigation. Most recently, tremendous increases in fertilizer prices have been driven by increased cost of natural gas required to manufacture fertilizers and exacerbated by the volatile socio-economic situation in countries-leading manufacturers and exporters of natural gas and fertilizers. The proposed project is relevant to the Sustainability of Pulse Production Systems priority area. The resilience of agricultural production systems necessitates higher efficiency in the use of agricultural inputs and natural resources including water and fertilizers. Pulses have unique properties that, if utilized, have a potential to conserve water, and enhance soil health through increased carbon sequestration and nitrogen fixation. Field trials will be conducted to 1) assess the water and nutrient footprint and demonstrate the value of improved water and nutrient use efficiency in pulse-wheat cropping systems, and 2) develop irrigation and nutrient management strategies for improved soil health through the rotation of pulses with wheat. Trials will consist of two rotation cycles of three pulse crops (chickpea [Cicer arietinum L.], lentil [Lens culinaris L.], and field pea [Pisum sativum L.]) planted at two seeding rates, followed by winter wheat (Triticum aestivum L.). Data will be collected on precipitation, soil moisture, water use efficiency, soil health, nitrogen use efficiency, and pulses and wheat yield and nutritional quality. Crop yield and water and nutrient inputs will be recorded for comprehensive economic analysis. Results from this project are likely to have an immediate impact by providing foundational knowledge needed by stakeholders to rotate pulses with wheat in a way that maximizes water and nutrient use, reduces reliance on costly chemical nitrogen fertilizers, and maintains overall soil fertility and sol health.

Objectives: Our goal is to provide the foundational knowledge needed by stakeholders to rotate pulses with wheat in a way that maximizes water and nutrient use, reduces reliance on costly chemical nitrogen fertilizers, and maintains overall soil fertility and sol health.

Specifically, we are aiming to:

For each crop rotation (chickpea-winter wheat, lentil-winter wheat, and pea-winter wheat):

1. Quantify and compare water use efficiency by:

a. Measuring and comparing:

i. soil moisture levels throughout the season and at pulse harvest

ii. biomass and yield production

2. Quantify and compare nitrogen use efficiency by:

a. Estimating the amount of nitrogen contributed by each of the three pulses planted at wo seeding rates to soil residual nitrogen pool and available for subsequently planted winter wheat uptake

b. Quantify and compare the winter wheat yield increases following each of the three pulse crops planted at two seeding rates

3. Evaluate and compare changes in soil health in pulses-wheat production systems by:

a. Comparing the soil health parameters after the pulses harvest with the preplant baseline soil health measurements

4. Quantify and compare the economic impact of integrating pulses into wheat-based cropping system by: 

a. Using crop yield, input usage, input cost, and price data to develop enterprise budgets for each crop rotation. 

Collaboration: Dr. Olga Walsh and Dr. Kurtis Schroeder are Associate Professors, Cropping Systems Agronomists. Dr. Olga Walsh will be the principal investigator for this project and ensure that all proposed activities outlined in the grant proposal are executed. Specifically, Dr. Olga Walsh will conduct and oversee the trials at Parma, recruit and supervise one graduate student working on the project, train the student on study design, establishment, data collection, and research methods. Dr. Olga Walsh will assist the student in summarizing data annually, data analyses, and taking the lead on year-end reporting, data compilation, and presentation. Dr. Kurtis Schroeder will conduct and oversee the trials at the Parker Farm site and supervise staff to assist in study establishment and data collection and reporting. With Dr. Olga Walsh, Dr. Kurtis Schroeder will co-advise a graduate student assigned to this project. Dr. Patrick Hatzenbuehler is an Assistant Professor, an Agricultural Economist. Dr. Patrick Hatzenbuehler performs evidence-based research and extension work on agricultural commodity markets with a focus on market structure and conditions for crops grown in Idaho. Dr. Patrick Hatzenbuehler will conduct the economic analysis annually and will provide final economic analysis results at the completion of the trials. Dr. Olga Walsh, Dr. Kurtis Schroeder, and Dr. Patrick Hatzenbuehler will collaborate on final data analysis, reporting, and producing journal and extension outreach publications.