Table 1
Number of Meloidogyne incognita race 3, M. arenaria race 1, M. javanica, and M. haplanaria in roots of susceptible and resistant pepper lines at 1, 3, and 5 days after inoculation.
| Days after nematode inoculation | |||
|---|---|---|---|
| Cultivar/line (resistant gene) | 1 | 3 | 5 |
| M. incognita race 3 | |||
| Mellow StarX | 11.0±1.24 a | 21.8±2.47 a | 39.0±4.50 a |
| Yolo Wonder B (Me5)Y | 8.1±1.16 a | 15.0±1.74 b | 38.1±3.9 a |
| Charleston Belle (N)Y | 0.6±0.30 b | 3.8±0.72 c | 7.5±0.90 bc |
| HDA-149 (Me3) | 0.3±0.30 b | 3.0±0.60 c | 5.1±0.74 c |
| HDA-330 (Me1) | 0.8±0.45 b | 7.3±0.83 c | 12.0±1.16 b |
| PM-217 (Me1,Me2) | 0.5±0.30 b | 6.3±1.32 c | 10.6±2.60 b |
| PM-687 (Me3,Me4) | 0.5±0.30 b | 3.8±1.20 c | 6.8±1.30 bc |
| M. arenaria race 1 | |||
| Mellow Star | 10.1±1.45 a | 17.1±2.93 a | 35.2±6.0 a |
| Yolo Wonder B | 7.8±1.85 a | 12.6±1.74 a | 37.0±5.8 a |
| Charleston Belle | 0.1±0.16 b | 2.3±0.77 b | 5.1±1.4 b |
| HDA-149 | 0.1±0.16 b | 3.0±0.77 b | 10.6±1.1 b |
| HDA-330 | 0.6±0.30 b | 5.0±0.78 b | 10.3±0.8 b |
| PM-217 | 0.3±0.30 b | 5.5±0.86 b | 9.5±1.1 b |
| PM-687 | 0.3±0.30 b | 4.6±1.67 b | 6.6±1.2 b |
| M. javanica | |||
| Mellow Star | 9.6±0.9 a | 18.7±2.3 a | 30.7±4.5 a |
| Yolo Wonder B | 0.5±0.06 b | 3.8±1.0 b | 9.8±1.2 b |
| Charleston Belle | 0.1±0.02 b | 2.1±0.7 b | 4.6±1.3 c |
| HDA-149 | 0.5±0.03 b | 4.8±1.0 b | 9.0±2.6 bc |
| HDA-330 | 0.6±0.1 b | 3.6±1.3 b | 5.8±1.1 bc |
| PM-217 | 0.3±0.02 b | 4.8±1.4 b | 9.3±2.3 b |
| PM-687 | 0.3±0.02 b | 1.8±0.72 b | 6.3±0.94 bc |
| M. haplanaria | |||
| Mellow Star | 7.2±1.04 a | 16.6±2.03 a | 21.1±2.1 a |
| Yolo Wonder B | 0.6±0.18 b | 4.5±0.8 b | 10.1±1.1 bc |
| Charleston Belle | 0.2±0.04 b | 2.5±0.8 b | 4.5±1.0 d |
| HDA-149 | 0.3±0.16 b | 3.9±0.7 b | 8.3±1.2 bc |
| HDA-330 | 0.3±0.06 b | 5.6±1.6 b | 9.6±2.1 bc |
| PM-217 | 0.3±0.06 b | 3.6±0.9 b | 10.8±1.1 b |
| PM-687 | 0.6±0.03 b | 4.3±1.3 b | 7.1±1.7 cd |
1 Notes: Xsusceptible control; Yresistant control. Each plant was inoculated with 300 second-stage juveniles of each nematode species at transplanting. For each nematode species, each value represents the mean ± standard error (n = 6) of each treatment. Means followed by the same letter within columns are not significantly different (p = 0.05) based on Tukey’s test.
Table 2
Root fresh weight, gall index, numbers of eggs per gram fresh root mass, and reproduction factor of Meloidogyne incognita race 3, M. arenaria race 1, M. javanica, and M. haplanaria on pepper cultivar/lines in two greenhouse trials.
| Cultivar/line | Root weight | Gall indexY | Eggs/g root | Reproduction factorZ |
|---|---|---|---|---|
| M. incognita race 3 | ||||
| Mellow StarX | 11.6±1.2 a | 3.7±0.6 a | 2,966.5±769.1 b | 33.9±7.37 b |
| Yolo Wonder BW | 11.2±1.4 a | 4.0±0.5 a | 4,387.4±1,037.6 a | 48.1±9.87 a |
| Charleston BelleW | 10.1±1.7 a | 0.5±0.3 b | 73.2±12.3 c | 0.6±0.09 c |
| HDA-149 | 10.3±1.5 a | 0.3±0.3 b | 6.5±2.0 c | 0.1±0.01 c |
| HDA-330 | 11.4±0.9 a | 0.7 ±0.2 b | 88.4±24.0 c | 0.9±0.27 c |
| PM-217 | 11.3±1.5 a | 0.2±0.3 c | 6.7±1.7 c | 0.1±0.02 c |
| PM-687 | 11.7±0.7 a | 0.3±0.3 b | 24.4±5.1 c | 0.3±0.06 c |
| M. arenaria race 1 | ||||
| Mellow Star | 11.1±1.4 a | 3.6±0.7 a | 3,205.3±718.1 a | 34.7±6.07 a |
| Yolo Wonder B | 10.0±1.5 a | 3.1±0.5 a | 3,163.4±904.2 a | 30.2±9.88 a |
| Charleston Belle | 11.1±1.2 a | 0.4±0.4 b | 10.6±0.8 b | 0.05±0.01 b |
| HDA-149 | 10.8±1.7 a | 0.4±0.3 b | 6.5±1.6 b | 0.07±0.02 b |
| HDA-330 | 10.1±1.3 a | 0.7±0.3 b | 32.8±9.3 b | 0.31±0.07 b |
| PM-217 | 10.7±1.6 a | 0.4±0.4 b | 8.4±1.7 b | 0.08±0.02 b |
| PM-687 | 11.5±1.1 a | 0.5±0.3 b | 3.5±0.9 b | 0.04±0.01 b |
| M. javanica | ||||
| Mellow Star | 11.7±1.3 a | 3.7±0.8 a | 2,059.5±454.0 a | 23.5±4.46 a |
| Yolo Wonder B | 9.4±1.6 a | 0.9±0.4 b | 5.0± 1.4 b | 0.04±0.01 b |
| Charleston Belle | 10.4±1.7 a | 0.4±0.4 b | 1.9±1.1 b | 0.01±0.01 b |
| HDA-149 | 9.5±1.5 a | 0.4±0.3 b | 10.1±3.6 b | 0.09±0.02 b |
| HDA-330 | 10.3±1.8 a | 0.5±0.4 b | 8.7±5.6 b | 0.06±0.03 b |
| PM-217 | 10.1±1.5 a | 0.4±0.3 b | 24.6±8.9 b | 0.24±0.01 b |
| PM-687 | 10.1±1.7 a | 0.7±0.3 b | 1.7±0.7 b | 0.01±0.00 b |
| M. haplanaria | ||||
| Mellow Star | 12.4±1.4 a | 2.7±1.25 a | 655.0±57.0 a | 8.1±1.25 a |
| Yolo Wonder B | 10.3±1.1 a | 0.3±0.02 b | 5.4±2.4 b | 0.06±0.02 b |
| Charleston Belle | 9.3±1.3 a | 0.4±0.06 b | 20.2±8.9 b | 0.17±0.06 b |
| HDA-149 | 10.7±1.1 a | 0.4±0.04 b | 12.7±4.9 b | 0.13±0.04 b |
| HDA-330 | 10.5±1.1 a | 0.7±0.07 b | 25.9±7.3 b | 0.27±0.07 b |
| PM-217 | 10.5±1.1 a | 0.4±0.01 b | 3.5±1.5 b | 0.03±0.01 b |
| PM-687 | 12.0±1.2 a | 0.6±0.04 b | 13.3±2.9 b | 0.15±0.03 b |
1 Notes: Xsusceptible control; Wresistant control; Each plant was inoculated with 1,000 second-stage juveniles of each nematode species at transplanting; Y rated on a scale of 0 to 5: 0 = no gall; 1 = 1 to 2 galls on root system, 2 = 3 to 10 galls, 3 = 11 to 30 galls, 4 = 31 to 100 galls, and 5 ⩾100 galls; Z Reproduction factor = final number of nematodes/initial number inoculated; Each value represents the mean ± standard error (n = 10) of each treatment. Means followed by the same letter within columns are not significantly different (p = 0.05) based on Tukey’s test.
Table 3
Resistance and susceptibility ratings of pepper plants to species of root-knot nematode (Meloidogyne spp.) based on greenhouse experiments.
| Cultivar/Line | Nematode resistance genes | M. incognita race 3 | M. arenaria race 1 | M. javanica | M. haplanaria |
|---|---|---|---|---|---|
| Mellow Star | None | HS | HS | HS | S |
| Yolo Wonder B | Me5 | HS | HS | HR | HR |
| Charleston Belle | N | HR | HR | HR | HR |
| HDA-149 | Me3 (=Me7) | HR | HR | HR | HR |
| HDA-330 | Me1 | R | HR | HR | HR |
| PM-217 | Me1, Me2 | HR | HR | HR | HR |
| PM-687 | Me3 (=Me7), Me4 | HR | HR | HR | HR |
1 Notes: Root gall index (GI) and reproduction factor (RF: final number of nematodes/initial number inoculated) were used to assess resistance/susceptibly ratings as follows: HR: highly resistant (GI < 1 and RF < 0.1), R: resistant (GI < 1 and RF ⩽1), S: susceptible (GI ≥ 2 and RF = 1 to 10), and HR: highly susceptible (GI ⩾ 3 and RF ⩾ 10).