Plant leaf diseases are a major threat to global agricultural productivity.
Early and accurate detection is essential for preventing crop damage and ensuring food security.
This project presents a comparative analysis of five Convolutional Neural Network (CNN) architectures for automated plant leaf disease classification using a publicly available dataset.
We implemented and evaluated:
- Basic CNN
- VGG16
- VGG19
- ResNet50
- InceptionResNetV2
The dataset was preprocessed with normalization, augmentation, and class balancing to improve generalization.
Models were trained under identical experimental conditions to ensure fair comparison.
- Source: Plant Disease Recognition Dataset
- Classes: Multiple plant disease categories + healthy leaves
- Data Splits: Train / Validation / Test
- Image Size: 224 Γ 224 pixels
- Augmentation Techniques:
- Random Flip
- Random Rotation
- Random Zoom
- Random Contrast
After training all models on the Plant Disease Recognition Dataset, we evaluated them using Accuracy, Precision, Recall, and F1-Score.
The table below summarizes the performance of each architecture:
| Model | Accuracy | Precision | Recall | F1-Score |
|---|---|---|---|---|
| Basic CNN | 93.99 | 0.93 | 0.92 | 0.92 |
| VGG16 | 80.67 | 0.82 | 0.80 | 0.80 |
| VGG19 | 84.67 | 0.85 | 0.84 | 0.84 |
| ResNet50 | 36.67 | 0.26 | 0.36 | 0.25 |
| InceptionResNetV2 | 92.00 | 0.92 | 0.92 | 0.92 |
Key Observations:
- The Basic CNN achieved the highest accuracy (93.99%) while maintaining low computational complexity, making it suitable for real-time and resource-limited applications.
- InceptionResNetV2 performed competitively with 92% accuracy, excelling in complex feature extraction but requiring more computational resources.
- VGG16 and VGG19 achieved moderate accuracy, performing well on high-contrast lesions but struggling with subtle disease symptoms.
- ResNet50 performed poorly on this dataset due to insufficient domain-specific fine-tuning, with an accuracy of only 36.67%.
Visual Evaluation:
- Confusion matrices were plotted for each model to analyze per-class performance.
- Predicted image samples demonstrated that Basic CNN and InceptionResNetV2 made consistent predictions across disease classes.