Table 5. Estimates of the specific and general combining ability (SCA and CGA, respectively) for root and shoot morphological attributes, used in the analysis of contrasting cacao genotypes for drought, submitted for 60 days to two water conditions (SI): control (ΨWL between -0.1 and -0.5 MPa) and stressed (ΨWLbetween -2.0 and -2.5 MPa).
Ilhéus, Bahia, Brazil.
| Source of Variation | DF | Mean Squares | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| H | CD | TLA | LN | ILA | LDB | SDB | TDB | LAR | SLA | LMR | RDB | R/S | RL | RA | RD | RV | RD < 1 | 1< RD < 2 | RD > 2 | ||
| (m) | (cm) | (m2) | (unit.) | m2.plant-1 | g.plant-1 | g.plant-1 | g.plant-1 | (m2. g-1) | (m2. g-1) | (g/g) | g.plant-1 | cm | cm2 | mm | cm3 | mm | mm | mm | |||
| PROG | 20 | 0.3*** | 36.4*** | 25922308.5*** | 1241.2*** | 7094.0*** | 1124.2*** | 2033.8*** | 7787.9*** | 609.7*** | 2438.6*** | 0.1*** | 311.1*** | 0.1*** | 2740921.0*** | 662209.0*** | 0.8*** | 41602.0*** | 316373.0** | 229150.0*** | 505578.0*** |
| CGA | 6 | 8.2*** | 54.3*** | 50184884.7** | 3153.9*** | 12650.9** | 2051.8*** | 3832.6*** | 12940.5*** | 373.6ns | 4500.3*** | 0.1* | 326.2*** | 0.2*** | 4656275.0*** | 999515.0*** | 0.9** | 67516.0*** | 360036.0** | 245226.0* | 523232.0** |
| SCA | 14 | 0.9** | 2878.0** | 15524061.1ns | 421.4** | 4711.8** | 726.7*** | 1262.9** | 5581.1** | 711.0 *** | 1555.1** | 0.1*** | 304.7*** | 0.0ns | 1920055.0* | 517649.0** | 0.7** | 30497.0** | 297660.0* | 222260.0** | 498013.0** |
| SI | 1 | 0.5** | 134.6*** | 73566219.1*** | 1472.5*** | 145.37ns | 10764.0** | 23.4ns | 13792.4** | 1517*** | 13793.3*** | 0.2*** | 75.2ns | 0.1*** | 1296967.0ns | 5775153.0*** | 37.2*** | 1050501.0*** | 4960373.0*** | 108150.0ns | 12021085.0*** |
| PROG x SI | 20 | 0.1** | 19.3* | 25771937.7** | 152.0ns | 3476.0** | 417.1** | 821.6** | 2550.4* | 434.9** | 1552.6*** | 0.1ns | 163.2** | 0.1** | 2026416.0** | 234308.0** | 0.6** | 25034.0** | 325898.0** | 310693.0*** | 315837.0* |
| CGA x SI | 6 | 0.1ns | 10.5ns | 23284304.3* | 110.6ns | 5006.3** | 370.7ns | 933.5** | 1913.5ns | 233.8ns | 1792.7** | 0.1ns | 126.2ns | 0.0ns | 2492091.0* | 312912.0* | 0.7* | 44276.0*** | 199644.0ns | 120041.0ns | 280235.0ns |
| SCA x SI | 14 | 0.1** | 23.0* | 26838066.3 ** | 170.5ns | 2820.6* | 436.9 ** | 774.9*** | 2823.3 * | 521.1** | 1449.8** | 0.1ns | 179.1** | 0.0*** | 1826840.0* | 200620.0* | 0.5* | 16787.0ns | 380006.0** | 392401.0*** | 331094.0* |
| Residual | 248 | 0.0 | 10.9 | 10427373.0 | 115.0 | 1621.5 | 181.1 | 353.1 | 1522.0 | 219.5 | 569.4 | 0.1 | 72.4 | 0.0 | 884697.0 | 116302.5 | 0.2 | 10905.1 | 142165.0 | 95446.1 | 180697.0 |
H, high; CD stem diameter; TLA, total leaf area; NL, leaves number; ILA, individual leaf area; LDB, leaf dry biomass; SDB, stem dry biomass; TDB, total dry biomass; LAR, leaf area ratio; SLA, specific leaf area; LMR, leaf mass ratio; RDB, root dry weight; R/S, root/shoot ratio; RL, root length; RA, root area; RD, average root diameter; RV, root volume; RD, fine root diameter (RD < 1 mm), medium (1 < RD < 2 mm) and coarse (< 2 mm).
*** significance by F test at p < 0.001
** p < 0.01
* p < 0.05.