JADAM Vs. Bacillus For Tomato Damping-Off

ISEF Category: Plant Sciences

Subcategory: Agriculture and Agronomy  ·  Difficulty: Intermediate  ·  Setup: School Lab  ·  Time: 1 to 2 Months

The Hook

A healthy-looking tray of tomato seeds can collapse fast. One day the stems stand up, and the next day seedlings fall over from damping-off. That makes this topic useful and very testable. You can compare a homemade microbial mix with a commercial inoculant and see which one protects young plants better.

What Is It?

Damping-off is a seedling disease that makes young plants rot at the soil line or fail before they emerge. Think of it like a weak spot in a straw. Once fungi or water molds attack that spot, the seedling can no longer stay upright.

JADAM-style microbial solutions use scraps and leaf mold to encourage a mixed microbial community. A commercial Bacillus subtilis inoculant usually contains a specific helpful bacterium that can crowd out harmful microbes or trigger plant defenses. Your project asks whether a rough, homemade mix can perform as well as a targeted product.

This topic sits at the edge of plant health, soil biology, and disease control. You are not just asking whether plants grow. You are asking which treatment lowers disease pressure under the same growing conditions.

Why This Is a Good Topic

This is a strong science fair topic because you can measure a real plant problem with clear outcomes, like seedling survival, stem collapse, and growth rate. You can also compare a low-cost homemade treatment with a commercial product, which connects to sustainable gardening and small-scale farming. A student can realistically learn experimental design, replication, controls, and basic statistics without needing a full research lab.

Research Questions

• How does a JADAM microbial solution affect tomato seedling survival compared with a commercial Bacillus subtilis inoculant?
• What is the effect of each treatment on the percentage of seedlings that show damping-off symptoms?
• Does the homemade ferment change seedling height or stem thickness more than the commercial inoculant?
• To what extent do the treatments change disease outcomes in sterile soil versus garden soil?
• Which treatment gives the most consistent results across repeated trays of tomato seedlings?
• How does the timing of treatment application change protection against damping-off?

Basic Materials

• Tomato seeds from one packet for genetic consistency.
• Small pots or seedling trays with drainage holes.
• Potting mix, plus a separate batch of the same mix for all groups.
• JADAM-style ferment ingredients, such as potato, leaf mold, water, and a covered container.
• Commercial Bacillus subtilis inoculant labeled for garden or seedling use.
• Distilled water for the control group.
• Digital kitchen scale with 0.1 g accuracy.
• Measuring cups or graduated cylinders.
• Spray bottles or labeled watering cups.
• Waterproof labels and a permanent marker.
• Ruler or caliper for seedling measurements.
• Phone camera for consistent photos.
• Disposable gloves and basic cleaning supplies.
• Notebook or spreadsheet for daily records.

Advanced Materials

• Autoclaved or pasteurized growth medium for tighter control of background microbes.
• Petri dishes and agar plates for optional microbial comparison work.
• Incubator or controlled-temperature growth area.
• Microscope for checking fungal growth or microbial contamination.
• pH meter for tracking ferment changes.
• Spectrophotometer or colorimeter for turbidity readings if you test liquid cultures.
• Selective media for Bacillus or common damping-off organisms, if your lab permits.
• Data logger for temperature and humidity.
• Statistical software for survival analysis and repeated-measures comparisons.

Software & Tools

• Google Sheets: Organizes survival counts, growth measurements, and treatment groups in one place.
• ImageJ: Measures seedling height, stem width, and image-based scoring from photos.
• Google Colab: Runs free Python notebooks for graphs, summaries, and basic statistics.
• RStudio Desktop: Fits survival models and compares treatments with stronger statistics.
• BioRender: Helps you make clear figures and diagrams for your final poster.

Experiment Steps

1. Define the exact disease outcome you will measure, such as emergence, collapse at the soil line, or final survival.
2. Choose one tomato variety, one soil mix, and one planting setup so the treatments stay comparable.
3. Decide how you will compare the homemade ferment, the commercial inoculant, and an untreated control.
4. Plan your replication scheme so each treatment has enough trays or pots for statistical comparison.
5. Build a measurement plan for both disease scores and plant growth, then keep it identical across groups.
6. Plan your data analysis before you plant, including which graphs and tests will answer your question best.

Common Pitfalls

• Letting the homemade ferment vary from batch to batch, which makes the treatment impossible to compare fairly.
• Using soil that already contains active damping-off pathogens in some trays but not others, which creates uneven disease pressure.
• Mixing up seedlings from different groups after germination, which breaks the treatment assignment.
• Judging success only by plant height, which can miss the actual disease outcome at the stem base.
• Recording photos under different light or angle conditions, which makes symptom scoring and image measurements less reliable.

What Makes This Competitive

A stronger project will do more than compare final seedling counts. You can add better controls, like soil-only and water-only groups, and you can measure more than one outcome, such as emergence, survival, and stem thickness. You can also test whether the homemade mix works in more than one soil type or under different disease pressure. Careful replication and the right statistics will make your results much more convincing.

Project Variations

• Compare the two treatments in sterile potting mix versus garden soil to see whether natural soil microbes change the result.
• Test tomato, cucumber, or pepper seedlings to see whether the protection pattern changes by crop.
• Score both visible disease and microbial community changes using plate counts or simple microscopy if your school lab allows it.

Learn More

• USDA National Institute of Food and Agriculture: Search for seedling disease, soil health, and biological control resources through USDA pages and fact sheets.
• NIH PubMed: Search for review articles on damping-off, Bacillus subtilis, and biological control in seedlings.
• Plant Disease: Search this journal for studies on damping-off pathogens and biocontrol trials.
• Phytopathology: Look for peer-reviewed work on plant disease suppression, soil microbes, and seedling protection.
• MIT OpenCourseWare: Search for introductory microbiology or plant biology course materials to review microbial growth and experimental design.