The impacts of mustard cover crops and seed meal on non-target soil arthropods, microbial community, and crop productivity.

Commodities

Practices

Integrated pest management (IPM) is an ecologically based pest management approach that promotes the integration of crop resistance, cultural and biological control tactics, and biorational insecticide applications based on decision-making guidelines to contribute to environmental safety and the sustainability of our production systems. Although non-insecticidal cultural approaches such as cover cropping are often promoted as environmentally friendly components of IPM, there is limited information about their impact on non-target organisms that play critical roles in nutrient cycling and the sustainability of our agroecosystems. This project is developed to investigate the impact of soil-incorporated mustard cover crops (green manure) and mustard byproducts, often used to improve soil nutrients and suppress subterranean pests, on non-target organisms, some of which are important contributors to plant residue decomposition and soil health. Through laboratory bioassays, I will determine the effects of soil biofumigation with brown mustard (Brassica juncea L.) seed meal on the springtail Folsomia candida (Collembola: Isotomidae) populations over time following the application. In the field, I will examine the impacts of the soil-incorporated brown mustard cover crop and seed meal on soil invertebrate and microbial communities as well as the decomposition rate of plant tissues. Additionally, I will evaluate wheat yield across treatments to determine the economic viability of biofumigation practices. The information generated through this research will help us to optimize our IPM practices to minimize negative impacts on beneficial macro- and microorganisms while maximizing long-term productivity and sustainability.

The overall goal of this project is to determine the impact of biofumigation on soil invertebrates, microbial communities, and overall crop yield. We will achieve this goal through two complementary objectives. Our third objective is designed for the effective delivery of findings to our regional stakeholders and farmers.

Objective 1: Evaluate the impact of biofumigation using brown mustard (Brassica juncea) seed meal on the springtail Folsomia candida (Collembola: Isotomidae)

1. Determine the effects of biofumigation on springtail survival
2. Quantify the population recovery time of springtails to reach similar levels to control treatments after biofumigation

Objective 2: Assess the impact of biofumigation on soil invertebrates and soil microbial communities, decomposition rate, and overall yield of the wheat in the field setting

1. Compare species richness and abundance of soil-dwelling insects in biofumigated and untreated soil
2. Evaluate the impact of post-biofumigation on the soil microbial community
3. Assess the decomposition rate of plant residues in biofumigated and untreated soil
4. Evaluate the effects of biofumigation treatments on crop productivity (a yield assessment)

Objective 3: Disseminate findings to the stakeholders and growers by organizing workshops and extension events, and facilitate discussions on implementing cultural practices that improve soil health.