Veronica's Research on Aeroponics

Dec 3, 2024

Master’s Research Presentation by Veronica

Topic: The effects of plant growth-promoting microorganisms on microbial community dynamics and plant growth responses of aeroponically cultivated spinach.

Introduction

  • Presenter: Veronica
  • Advisor: Dr. Mackey, with committee members Drs. Alan Robertis and Josh Sharp.
  • Focus: Addressing issues with conventional soil-based agriculture and exploring aeroponic systems as a solution.

Conventional Agriculture Challenges

  • Utilizes 37% of the earth's land with only 12.21% being truly arable.
  • Involves soil-degrading practices: over-fertilization, pesticide use, monoculture.
  • Results: reduced yields, lower biodiversity, reduced soil quality.
  • Additional issues include agrochemical pollution and public health problems.
  • Regional challenges in Upper Peninsula of Michigan due to cold climates, short growing seasons leading to food insecurity.

Solutions Explored

Organic Systems

  • Benefits: increase soil carbon, improve soil quality, decrease erosion.
  • Criticism: lower yields and not addressing climate issues in Upper Peninsula.

Indoor Growing Systems

  • Hydroponics: Water-based nutrient solution systems.
  • Aeroponics: Subgroup of hydroponics using misting techniques for nutrient delivery.
    • Advantages:
      • Year-round operation indoors.
      • Up to 98% less water, 60% less fertilizer, and 100% less pesticide usage.
      • Potentially increased nutritional value of plants.
    • Disadvantages:
      • Sensitive to nutrient application errors, expensive setup, power outage vulnerability.

Research Methods

  • Objective: Evaluate the impact of organic amendments and microorganisms on aeroponic and soil-based systems.
  • Treatments: Regular aeroponics (RA), Modified Aeroponics (MA), Soil (S).
  • Components:
    • Vermicompost Tea: Organic nutrients.
    • Plant Growth Promoting Microorganisms (PGPMs): Enhance growth through various mechanisms.

Microorganism Details

  • Types: Epiphytes (surface colonizers) and Endophytes (internal colonizers).
  • Selected Microorganisms: Varied between treatments, focus on useful bacteria and fungi.
  • Inoculant Application: Weekly addition during water changes.

Results

Plant Growth

  • Mycorrhizal inoculants improved germination rates and initial stem length.
  • No significant difference in final stem length across treatments.

Microbial Community Analysis

  • Fungal communities differed by treatment; bacterial communities by both treatment and tissue type.
  • Richness varied significantly between epiphytic and endophytic environments.

Pathogen Prevalence

  • Pathogens Detected: Alternaria alternata was common in RA, reduced in MA and soil.

Nutritional Content and Yield

  • Soil had higher nitrogen, potassium, phosphorus, and sulfur levels, but lower sodium, copper, boron, and calcium.
  • Aeroponics achieved more consistent nutrient levels.
  • Leaf and root weights were higher in aeroponic treatments.

Conclusions

  • Microbial Composition: Varied significantly between treatments and tissue types.
  • Yield and Nutritional Quality: Enhanced in aeroponic systems.
  • Potential for Aeroponics: Offers a sustainable option for increasing food production in cold climates.

Q&A Highlights

  • Cost estimate for aeroponic systems: Approximately $425, with lights being a major cost.
  • Misting timing was 2 seconds on, 5 seconds off.
  • Queries on vermicompost tea microbiome and pathogens.

Veronica’s research illustrates promising potential for aeroponics in sustainable agriculture, particularly in cold climate regions like the Upper Peninsula, addressing food insecurity through enhanced yield and nutritional quality.