Table 7.
Glycine max cv. Williams 82 and G. soja CH4 responses to inoculation with S. fredii pSym-cured derivatives carrying different S. fredii pSym plasmids.
| Legume | S. fredii | Symbiotic plasmid | Number of nodules | Shoot dry- |
|---|---|---|---|---|
| inoculant | present | per plantA,B,C | weight (mg) | |
| G. max cv. Williams | HH103-M | pSfHH103d::Tn5-Mob | 79.5 ± 6.9A a | 2612 ± 424 a |
| NGR234 | pSfNGR234a | Nod-B | 645 ± 271 b | |
| NGR234-M | pSfNGR234a::Tn5-Mob | Nod-B | 700 ± 205 b | |
| NGR234C | None | Nod-C | 545 ± 220 b | |
| NGR234C pSymHH103M | pSfHH103d::Tn5-Mob | 49.0 ± 16.3D b | 480 ± 244 b | |
| USDA193C | None | Nod-C | 647 ± 122 b | |
| USDA193C pSymNGR234M | pSfNGR234a::Tn5-Mob | Nod-B | 508 ± 77 b | |
| Uninoculated | – | – | 507 ± 190 b | |
| G. soja CH4 | HH103-M | pSfHH103d::Tn5-Mob | 5.8 ± 2.4A b | 239 ± 110 a |
| NGR234 | pSfNGR234a | 3.8 ± 1.1 bc | 216 ± 83 ab | |
| NGR234-M | pSfNGR234a::Tn5-Mob | 3.2 ± 1.2A c | 161 ± 47 c | |
| NGR234C | None | Nod-C | 55 ± 18 d | |
| NGR234C pSymHH103M | pSfHH103d::Tn5-Mob | 19.9 ± 5.6D a | 66 ± 20 d | |
| USDA193C | None | Nod-C | 57 ± 13 d | |
| USDA193C pSymNGR234M | pSfNGR234a::Tn5-Mob | 3.7 ± 1.0A bc | 181 ± 86 bc | |
| Uninoculated | – | – | 64 ± 13 d | |
Three Leonard jars containing two (G. max) or four (G. soja) seedlings were inoculated with each bacterial strain. Numbers are mean values ± standard errors. Statistical comparisons among inoculants are shown using ANOVA. For each parameter, data followed by the same small letter are not significantly different at α = 5%.
Plants were analyzed 42 days after inoculation.
AGreen plants with pink nodules of normal external morphology were formed.
BYellow plants with macroscopic root outgrowths (MRO) were present.
CYellow plants and absence of MRO.
DYellow plants and small white ineffective nodules.
Uninoculated controls remained non-nodulated.