Table 2. Stemona cecropia in oil palm: average tissue cosumption of larvae at different stages* |
|||||
| Stage | Duration (days) |
Daily consumption (cm²) |
Total tissue consumption (cm²) |
Larvae /leaf |
No of larvae to cause 20% defoliation |
|---|---|---|---|---|---|
| 1 | 2 | 0.000 | 0.00 | - | - |
| 2 | 3 | 0.040 | 0.08 | 729 | 29,167 |
| 3 | 4 | 0.046 | 0.14 | 634 | 25,362 |
| 4 | 5 | 0.090 | 0.36 | 324 | 12,963 |
| 5 | 5 | 0.200 | 0.80 | 146 | 5,833 |
| 6 | 6 | 0.250 | 1.25 | 117 | 4,667 |
| 7 | 7 | 1.736 | 10.42 | 17 | 672 |
| 8 | 8 | 6.492 | 45.45 | 4 | 180 |
| Total | 40 | 58.50 | |||
|
* Estimated with data of Genty (1978). One day was eliminated from each stage, since larvae do not feed when molting. Assuming a leaf rate production of approximately 2 per month, and 7 m² per leaf |
|||||