Table 1.
Response of five sweetpotato (Ipomaea batatas) cultivars to inoculation with Meloidogyne enterolobii in this study.
| Factor | Fibrous fresh root weightu (g) | Gall indexv | Egg mass indexv | Eggs per egg mass | Eggs per fibrous fresh root weight | Eggs per gram fresh rootx | RFw |
|---|---|---|---|---|---|---|---|
| Sweetpotato cultivar t | |||||||
| Beauregard | 15.21 bc | 4.65 a | 3.65 b | 475 a | 30,975 c | 2,668 c | 6.20 c |
| Covington | 14.99 bc | 4.25 a | 4.45 ab | 490 a | 84,585 b | 5,683 ab | 16.92 b |
| Evangeline | 22.70 a | 4.65 a | 4.80 a | 503 a | 150,070 a | 7,161 a | 30.01 a |
| Hernandez | 16.35 b | 4.70 a | 4.90 a | 462 a | 113,235 b | 6,979 a | 22.65 b |
| Orleans | 11.65 c | 1.95 b | 2.30 c | 475 a | 42,022 c | 3,678 bc | 8.41 c |
| Test | |||||||
| Test 1 | 15.42 | 4.24 | 4.22 | 504 | 81,325 | 5,444 | 16.27 |
| Test 2 | 16.94 | 3.84 | 3.82 | 459 | 87,030 | 5,024 | 17.41 |
| F probability cv | < 0.001 | < 0.001 | < 0.001 | > 0.50 | < 0.001 | < 0.001 | < 0.001 |
| F probability test | 0.12 | 0.06 | 0.10 | > 0.50 | 0.46 | 0.50 | 0.46 |
| Tomato | 37.7 | 5 | 5 | n/ax | 176,340 | 4,801 | 35.27 |
1 Notes: tInoculum level: 5,000 eggs/plant; uMeans are average of duplicate tests, each with 10 and 5 replicates for all sweetpotato cultivars and tomato, respectively. Means followed by a common letter are not different according to Duncan’s multiple-range test (p ≤ 0.001); vGall and egg mass index: 0 = 0 galls or egg masses, 1 = 1 to 2 galls or egg masses, 2 = 3 to 10 galls or egg masses, 3 = 11 to 30 galls or egg masses, 4 = 31 to 100 galls or egg masses, and 5 = ≥ 100 galls or egg masses per root system (Taylor and Sasser, 1978); wRF = reproduction factor (Sasser et al., 1984); xn/a = Not applicable.
Figure 1:
Sweetpotato cv. Hernandez infected with Meloidogyne enterolobii. (A) Symptoms induced in the storage roots 90 days after nematode inoculation; (B) Necrosis and cracks of storage roots, induced by M. enterolobii; also, noticeable galls and egg masses on fibrous roots; (C) A close up of the galls and large egg masses on both fibrous and storage roots; and (D) Close up of necrosis and cracks in storage roots.