Scale | % Disease severity | Description |
0 | 0.0 | Leaves free from leaf spot |
1 | 0% - 5% | 0 - 5 per cent leaf area infected and covered by spots |
2 | 6% - 20% | 6 - 20 percent leaf area infected and covered by spots |
3 | 21% - 40% | 21 - 40 per cent leaf area infected and covered by spots |
4 | 41% - 70% | 41 - 70 per cent leaf area infected and covered by spots |
5 | >70% | >71 per cent leaf area infected and covered by spots |