Figure 1

Figure 2.

Figure 3.

Figure 4.

Cost estimates for the possible EPN-augmentation approaches in guava orchards to achieve maximum suppression of Caribfly at the best IJ ratea_
| Strategic EPN-augmentation option | In series, number of fruit tree−1 on the ground | Total number of fruit on the ground in 1 hectareb | Required IJs ha−1 of Heterorhabditis bacteriophora | Estimated cost of total number of IJs (US$ ha−1) |
|---|---|---|---|---|
| Hectare-wide EPN-augmentation or broadcasting at ‘(50 IJs cm−2 spread over a fruit in 350 cm2)’ seems to be less cost-effective | na | na | 5 × 109 | 970c |
| Applying Heterorhabditis bacteriophora IJs over each infested fruit on soil surface at 17,500 IJs fruit−1 seems to be more economical | ⩽1 | ⩽500 | 8,750,000 | 1.70 |
| 2 | 1,000 | 17,500,000 | 3.40 | |
| 3 | 1,500 | 26,250,000 | 5.10 | |
| 4 | 2,000 | 35,000,000 | 6.79 | |
| 5e | 2,500 | 43,750,000 | 8.49 | |
| 6 | 3,000 | 52,500,000 | 10.19 | |
| 7 | 3,500 | 61,250,000 | 11.88 | |
| 8 | 4,000 | 70,000,000 | 13.58 | |
| 9 | 4,500 | 78,750,000 | 15.28 | |
| 10 | 5,000 | 87,500,000 | 16.98 | |
| The average costs of Heterorhabditis bacteriophora IJs ha−1 in each month | 9.34d | |||
Cost-benefit analysis showing changing annual base net income level in response to varying total costs following inclusion of Heterorhabditis bacteriophora in Caribfly IPM plans to suppress Caribfly (Anastrepha suspensa) better in south Florida guava orchards_
| Methods to include Heterorhabditis bacteriophora in Caribfly IPM | |||
|---|---|---|---|
| Before inclusion of Heterorhabditis bacteriophora in IPM | Spot treatment technique | Hectare-wide broadcasting | |
| Details | US$ ha−1 | US$ ha−1 | US$ ha−1 |
| 1. Production costsa | |||
| Irrigation | 494 | 494 | 494 |
| Fertilizers | 1,359 | 1,359 | 1,359 |
| Insecticides | 1,112 | 1,112 | 1,112 |
| Herbicides | 1,112 | 1,112 | 1,112 |
| Fungicides | 988 | 988 | 988 |
| Heterorhabditis bacteriophora (in Table 1) | 0 | 267 | 4,850 |
| Labor (pruning; supervision; others) | 1,606 | 1,606 | 1,606 |
| Interest on capital (5%) | 334 | 347 | 576 |
| 2. Fixed costs | |||
| Cash overhead: | |||
| Insurance | 247 | 247 | 247 |
| Taxes | 247 | 247 | 247 |
| Non-cash overhead: | |||
| Land rent | 1,236 | 1,236 | 1,236 |
| Other overhead | 1,483 | 1,483 | 1,483 |
| 3. Harvesting and marketing costs | |||
| Picking and sales cost | 6,919 | 6,919 | 6,919 |
| 4. Total costs | 17,137 | 17,417 | 22,229 |
| 5. Returns on ‘wholesale base yield’ | |||
| Annual wholesale base revenueb, c | 39,537 | 39,537 | 39,537 |
| Annual base net incomed | 22,400 | 22,120 | 17,308 |