Table 1.
Effect of hot water on paralyzed nematode percentage of three nematode species (Aphelenchoides besseyi, Pratylenchus penetrans, and Meloidogyne hapla; n = 20) immediately after treatment at 40, 44, 48, and 52°C for 1, 5, 10, 30, 60, 120, and 240 min.
| Factor | Treatment level | 40°C | 44°C | 48°C | 52°C |
|---|---|---|---|---|---|
| Nematode (N) | A. besseyi | 50.8b | 70.0c | 99.3a | 100.0a |
| P. penetrans | 47.1b | 75.7b | 98.9a | 99.9a | |
| M. hapla | 63.0a | 100.0a | 100.0a | 100.0a | |
| Exposure time (T) | 1 min | 1.1e | 45.3d | 96.9b | 99.7a |
| 5 min | 10.8d | 56.4c | 98.9ab | 100.0a | |
| 10 min | 33.1c | 77.2b | 100.0a | 100.0a | |
| 30 min | 58.6b | 94.4a | 100.0a | 100.0a | |
| 60 min | 88.9a | 100.0a | 100.0a | 100.0a | |
| 120 min | 90.8a | 100.0a | 100.0a | 100.0a | |
| 240 min | 92.2a | 100.0a | 100.0a | 100.0a | |
| P value | N | < 0.0001 | < 0.0001 | 0.1075 | 0.3714 |
| T | < 0.0001 | < 0.0001 | 0.0005 | 0.4295 | |
| N × T | < 0.0001 | < 0.0001 | 0.2769 | 0.4545 |
Figure 1:
Paralyzed nematode percentage of three nematode species (Aphelenchoides besseyi, Pratylenchus penetrans and Meloidogyne hapla; n = 20) immediately after heat treatment at temperatures 40 and 44°C for various exposure times. Data were combined over two experiments and are means of six replications.
Table 2.
Effect of hot water on mortality percentage of three nematode species (Aphelenchoides besseyi, Pratylenchus penetrans, and Meloidogyne hapla; n = 20) 24 hr post heat treatment at 40, 44, 48, and 52°C for 1, 5, 10, 30, 60, 120, and 240 min.
| Factor | Treatment level | 40°C | 44°C | 48°C | 52°C |
|---|---|---|---|---|---|
| Nematode (N) | A. besseyi | 45.4a | 68.9b | 99.5ab | 100.0a |
| P. penetrans | 23.5c | 62.4c | 98.8b | 99.9a | |
| M. hapla | 31.1b | 86.9a | 100.0a | 100.0a | |
| Exposure time (T) | 1 min | 1.7e | 4.7d | 96.7b | 99.7a |
| 5 min | 4.2e | 40.6c | 99.4a | 100.0a | |
| 10 min | 6.1de | 75.3b | 100.0a | 100.0a | |
| 30 min | 17.8cd | 89.7a | 100.0a | 100.0a | |
| 60 min | 28.9c | 98.9a | 100.0a | 100.0a | |
| 120 min | 79.4b | 100.0a | 100.0a | 100.0a | |
| 240 min | 95.0a | 100.0a | 100.0a | 100.0a | |
| P value | N | < 0.0001 | < 0.0001 | 0.0007 | 0.3714 |
| T | < 0.0001 | < 0.0001 | < 0.0001 | 0.4294 | |
| N × T | < 0.0001 | < 0.0001 | < 0.0001 | 0.4543 |
Figure 2:
Mortality percentage of three nematode species (Aphelenchoides besseyi, Pratylenchus penetrans and Meloidogyne hapla; n = 20) 24 hr after heat treatment at temperatures 40, 44, and 48°C for various exposure times. Data were combined over two experiments and are means of six replications.
Table 3.
Effect of aerated steam at 44°C on reproduction of three nematode species (Aphelenchoides besseyi, Pratylenchus penetrans and Meloidogyne hapla) and plant dry weight (g) of strawberry under various exposure timesa.
| A. besseyi | P. penetrans | M. hapla | |||||
|---|---|---|---|---|---|---|---|
| Treatment | Nematodes per pot | Foliage dry wt. | Nematodes per pot | Plant dry wt. | Nematodes per pot | Eggs per root system | Plant dry wt. |
| 60 min exposure | 953a | 2.2a | 225b | 3.7ab | 3b | 480b | 5.1a |
| 120 min exposure | 78b | 1.8a | 145bc | 3.8ab | 0.1b | 552b | 4.8a |
| 240 min exposure | 0b | 2.4a | 69bc | 3.1b | 0b | 0b | 5.5a |
| Inoculated untreated control | 1267a | 1.8a | 462a | 4.5a | 67a | 19042a | 6.1a |
| Uninoculated untreated control | 0b | 2.9a | 0c | 4.9a | 0b | 0b | 5.0a |
| P value | < 0.0001 | 0.1163 | < 0.0001 | 0.0032 | < 0.0001 | < 0.0001 | 0.7167 |