Table 1. The H-, G-, and S-lignin-derived pyrolysis products in the control and S. hermonthica-infected rice roots of the resistant cultivar ‘Nipponbare’ and the susceptible cultivar ‘Koshihikari’.
Data are means ± se (se) of three biological replications. Each biological replicate contained a pool of two to five plants, from which at least four S. hermonthica-infected roots were obtained. In parentheses is the retention time relative to that of guaiacol. Asterisks indicate statistically significant difference between infected and control plants or between S. hermonthica-infected Nipponbare and Koshihikari. Student’s t test: *P < 0.05, **P < 0.01. Nb, Nipponbare; Ko, Koshihikari.
| Compound Name (Relative Time of Guaiacol) | Nipponbarea | Koshihikaria | Nb FC | Ko FC | Nb/Ko FC | ||
|---|---|---|---|---|---|---|---|
| Control | Infected | Control | Infected | Infected/ Control | Infected/ Control | Nb-infected/ Ko-infected | |
| H-lignin–derived | |||||||
| Phenol (0.81) | 1,270,246 ± 29,372 | 1,845,540 ± 79,604 | 1,453,507 ± 130,454 | 1,633,293 ± 33,784 | 1.5** | 1.1 | 1.1 |
| 4-Methylphenol, p-cresol (0.96), 3-methylphenol, m-cresol (0.97) | 400,879 ± 4,378 | 813,433 ± 57,893 | 560,418 ± 89,345 | 581,797 ± 62,150 | 2.0* | 1.0 | 1.4 |
| 4-Ethylphenol (1.11) | 34,710 ± 705 | 148,776 ± 26,295 | 96,106 ± 40,519 | 77,858 ± 43,980 | 4.3* | 0.8 | 1.9 |
| 4-Vinylphenol (1.18) | 2,494,814 ± 134,938 | 6,509,439 ± 685,101 | 4,654,667 ± 1,024,820 | 4,946,889 ± 366,924 | 2.6* | 1.1 | 1.3 |
| 4-Hydroxybenzoic acid methyl ester (1.50) | 4,044 ± 525 | 10,905 ± 1,411 | 7,578 ± 1,342 | 8,884 ± 1,336 | 2.7* | 1.2 | 1.2 |
| 4-Hydroxybenzoic acid (1.56) | 14,747 ± 1,198 | 19,176 ± 1,512 | 14,892 ± 898 | 15,763 ± 1,643 | 1.3 | 1.1 | 1.2 |
| G-lignin–derived | |||||||
| Guaiacol (1.00) | 592,969 ± 13,684 | 904,034 ± 76,644 | 664,409 ± 83,777 | 723,499 ± 22,869 | 1.5 | 1.1 | 1.2 |
| 4-Ethylguaiacol (1.29) | 101,381 ± 3,815 | 168,154 ± 19,597 | 114,056 ± 20,107 | 102,895 ± 7,800 | 1.7 | 0.9 | 1.6* |
| 4-Vinylguaiacol (1.34) | 7,257,631 ± 120,921 | 9,211,009 ± 833,344 | 8,092,399 ± 1,503,311 | 6,358,186 ± 540,390 | 1.3 | 0.8 | 1.4* |
| Eugenol (1.40) | 32,067 ± 1,133 | 75,785 ± 7,204 | 43,470 ± 5,981 | 61,060 ± 3,910 | 2.4* | 1.4 | 1.2 |
| 4-Propylguaiacol (1.42) | 4,803 ± 204 | 9,768 ± 856 | 5,915 ± 836 | 6,758 ± 655 | 2.0** | 1.1 | 1.4* |
| Vanillin (1.44) | 380,154 ± 25,208 | 993,165 ± 117,407 | 642,882 ± 152,228 | 759,209 ± 40,750 | 2.6** | 1.2 | 1.3 |
| Cis-isoeugenol (1.47) | 14,470 ± 127 | 22,511 ± 2,626 | 16,505 ± 2,887 | 15,245 ± 1,375 | 1.6 | 0.9 | 1.5 |
| Homovanillin (1.52) | 13,794 ± 1,091 | 20,999 ± 2,071 | 15,641 ± 2,279 | 17,369 ± 2,400 | 1.5* | 1.1 | 1.2 |
| Transisoeugenol (1.52) | 115,861 ± 2,535 | 321,691 ± 32,588 | 174,448 ± 24,417 | 254,758 ± 19,272 | 2.8* | 1.5 | 1.3 |
| Acetovanillone (1.56) | 18,189 ± 10,078 | 16,126 ± 610 | 10,787 ± 1,116 | 14,457 ± 1,762 | 0.9 | 1.3 | 1.1 |
| 1-(4-Hydroxy-3-methoxyphenyl)propyne (1.56) | 18,660 ± 1,038 | 48,196 ± 3,634 | 26,111 ± 3,900 | 45,947 ± 2,037 | 2.6** | 1.8* | 1.0 |
| 1-(4-Hydroxy-3-methoxyphenyl)allene (1.57) | 15,933 ± 811 | 43,269 ± 3,111 | 24,907 ± 4,740 | 41,764 ± 3,009 | 2.7** | 1.7* | 1.0 |
| Vanillic acid methyl ester (1.58) | 2,136 ± 137 | 3,558 ± 380 | 1,725 ± 286 | 2,952 ± 424 | 1.7* | 1.7 | 1.2 |
| Guaiacylacetone (1.61) | 9,211 ± 191 | 24,013 ± 2,395 | 11,469 ± 2,382 | 17,706 ± 1,490 | 2.6* | 1.5 | 1.4 |
| Vanillic acid (1.63) | 1,560 ± 126 | 2,449 ± 318 | 2,002 ± 138 | 1,677 ± 75 | 1.6 | 0.8 | 1.5 |
| Propiovanillone (1.66) | 2,197 ± 228 | 7,184 ± 678 | 4,330 ± 1,176 | 5,196 ± 1,063 | 3.3** | 1.2 | 1.4 |
| Guaiacyl vinyl ketone (1.67) | 2,669 ± 207 | 6,734 ± 430 | 4,354 ± 666 | 5,467 ± 427 | 2.5** | 1.3 | 1.2 |
| Cis-coniferyl alcohol (1.76) | 475 ± 77 | 7,225 ± 1,146 | 3,530 ± 890 | 5,594 ± 1,282 | 15.2* | 1.6 | 1.3 |
| Transconiferaldehyde (1.84) | 6,849 ± 914 | 39,102 ± 4,576 | 18,223 ± 3,318 | 35,559 ± 3,212 | 5.7* | 2.0* | 1.1 |
| Transconiferyl alcohol (1.85) | 2,775 ± 231 | 29,533 ± 5,410 | 14,193 ± 3,092 | 27,849 ± 5,680 | 10.6* | 2.0 | 1.1 |
| S-lignin–derived | |||||||
| 2,6-Dimethpxyphenol (1.38) | 247,775 ± 2,869 | 531,627 ± 60,415 | 339,686 ± 78,624 | 379,911 ± 25,686 | 2.1* | 1.1 | 1.4 |
| 2,6-Dimethoxy-4-methylphenol (1.50) | 165,457 ± 5,111 | 368,493 ± 48,984 | 233,368 ± 48,881 | 227,911 ± 216,23 | 2.2 | 1.0 | 1.6 |
| 4-Ethyl-2,6-dimethoxyphenol (1.60) | 14,251 ± 285 | 28,021 ± 3,799 | 18,352 ± 2,380 | 16,972 ± 1,210 | 2.0 | 0.9 | 1.7 |
| 2,6-Dimethoxy-4-vinylphenol (1.65) | 238,975 ± 3,360 | 523,463 ± 64,666 | 320,357 ± 63,586 | 375,457 ± 23,647 | 2.2* | 1.2 | 1.4 |
| 4-Allyl-2,6-dimethoxyphenol (1.69) | 68,774 ± 1,284 | 151,548 ± 18,591 | 97,133 ± 19,695 | 104,069 ± 9,975 | 2.2* | 1.1 | 1.5 |
| 2,6-Dimethoxy-4-propylphenol (1.71) | 4,281 ± 250 | 9,076 ± 1,146 | 5,779 ± 873 | 5,561 ± 253 | 2.1* | 1.0 | 1.6 |
| Syringaldehyde (1.75) | 52,870 ± 2,022 | 161,372 ± 22,785 | 93,299 ± 23,055 | 114,677 ± 10,045 | 3.1* | 1.2 | 1.4 |
| Cis-2,6-dimethoxy-4-propenylphenol (1.75) | 50,618 ± 486 | 127,789 ± 11,974 | 78,130 ± 12,948 | 92,095 ± 8,456 | 2.5* | 1.2 | 1.4 |
| Homosyringaldehyde (1.80) | 741 ± 126 | 111 ± 61 | 559 ± 282 | 457 ± 324 | 0.2* | 0.8 | 0.2 |
| 1-(3,5-Dimethoxy-4-hydroxyphenyl)propyne (1.80) | 29,974 ± 811 | 69,727 ± 7,295 | 48,014 ± 8,540 | 62,367 ± 3,977 | 2.3* | 1.3 | 1.1 |
| Trans-2,6-dimethoxy-4-propenylphenol (1.81) | 290,064 ± 5,771 | 782,051 ± 78,985 | 436,701 ± 85,610 | 546,315 ± 49,671 | 2.7* | 1.3 | 1.4 |
| Acetosyringone (1.83) | 17,093 ± 182 | 48,955 ± 6,247 | 25,882 ± 5,363 | 36,040 ± 2,387 | 2.9* | 1.4 | 1.4 |
| Syringylacetone (1.87) | 1,045 ± 150 | 30,919 ± 3,634 | 16,874 ± 4,034 | 22,125 ± 2,095 | 2.8* | 1.3 | 1.4 |
| Syringic acid methyl ester (1.87) | 1,811 ± 167 | 2,754 ± 303 | 1,976 ± 185 | 2,939 ± 293 | 1.5 | 1.5 | 0.9 |
| Syringic acid (1.87) | 655 ± 265 | 329 ± 165 | 582 ± 301 | 996 ± 751 | 0.5 | 1.7 | 0.3 |
| 3-(3,5-Dimethoxy-4-hydroxyphenyl)-3-oxopropanal (1.93) | 2,690 ± 229 | 6,372 ± 780 | 4,216 ± 1,125 | 3,505 ± 490 | 2.4* | 0.8 | 1.8* |
| Propiosyringone (1.93) | 6,243 ± 367 | 17,788 ± 2,135 | 9,368 ± 865 | 12,439 ± 1,007 | 2.8* | 1.3 | 1.4 |
| Syringyl vinyl ketone (1.93) | 2,245 ± 406 | 4,711 ± 1,398 | 4,260 ± 693 | 3,165 ± 291 | 2.1 | 0.7 | 1.5 |
| Dihydrosinapyl alcohol (2.00) | 1,621 ± 136 | 4,224 ± 1,359 | 3,199 ± 602 | 6,485 ± 442 | 2.6 | 2.0* | 0.7 |
| Cis-sinapyl alcohol (2.02) | 365 ± 123 | 3,128 ± 434 | 1,452 ± 151 | 2,546 ± 254 | 8.6** | 1.8* | 1.2 |
| Transsinapaldehyde (2.09) | 1,277 ± 60 | 2,826 ± 324 | 1,559 ± 488 | 1,662 ± 179 | 2.2* | 1.1 | 1.7* |
| Transsinapyl alcohol (2.09) | 1,384 ± 160 | 9,469 ± 1,511 | 5,365 ± 597 | 8,068 ± 992 | 6.8* | 1.5 | 1.2 |
| Other lignin-derived compounds | |||||||
| 4-Methoxytoluene (0.90)_3-methoxytoluene (0.90) | 13,947 ± 342 | 24,991 ± 1,723 | 15,499 ± 2,265 | 20,736 ± 835 | 1.8* | 1.3 | 1.2 |
| 2-Methylphenol, o-cresol (0.93) | 58,793 ± 1,520 | 108,422 ± 7,842 | 71,604 ± 9,795 | 81,236 ± 5,608 | 1.8* | 1.1 | 1.3 |
| 2,6-Dimethylphenol (1.03) | 3,932 ± 1,004 | 6,258 ± 3,337 | 3,965 ± 1,394 | 6,299 ± 1,497 | 1.6 | 1.6 | 1.0 |
| 2,4-Dimethylphenol (1.08) | 23,350 ± 296 | 56,546 ± 4,615 | 33,325 ± 6,055 | 36,353 ± 4,316 | 2.4* | 1.1 | 1.6 |
| Catechol (1.14) | 2,020 ± 682 | 240,049 ± 48,230 | 169,641 ± 54,198 | 205,743 ± 34,391 | 118.8* | 1.2 | 1.2 |
| 3-Methoxycatechol (1.26) | 36,340 ± 4,058 | 156,635 ± 24,403 | 95,841 ± 25,186 | 120,629 ± 12,172 | 4.3* | 1.3 | 1.3 |
| 4-Methoxycatechol (1.27) | 3,649 ± 1,829 | 65,816 ± 13,206 | 23,198 ± 10,183 | 31,514 ± 7,688 | 18.0* | 1.4 | 2.1 |
a
Peak area values of the GC-MS total ion-current chromatograms of the pyrolysates.