Table 9.
Standard coefficient estimates (Beta values) from regression results of explanatory agro-morphological parameters on grain yield for sorghum lines with variable early season cold tolerance and susceptibility evaluated at three planting dates in West Texas.
| Categories | Assessed parameters | Early planting | Mid planting | Standard Planting |
|---|---|---|---|---|
| Plant morphology | Number of leaves | 0.040 | − 0.029 | 0.005 |
| Days to flowering | − 0.021 | − 0.010 | 0.003 | |
| Plant height | 0.009 | − 0.021 | − 0.010 | |
| Basal tillers | 0.022 | − 0.017 | − 0.005 | |
| Nodal tillers | − 0.037 | − 0.035* | 0.013 | |
| Stem diameter | 0.029 | − 0.011 | − 0.015 | |
| Peduncle length | 0.035 | − 0.001 | − 0.006 | |
| Panicle size | Panicle length | 0.400* | 0.497* | 0.046 |
| Panicle width | 0.430* | 0.552* | 0.048 | |
| Panicle area | − 0.697* | − 0.830* | − 0.085 | |
| Yield related | Panicle weight | 0.850 | 1.078* | − 0.252 |
| Vegetative biomass | 0.453 | 0.010 | 0.622 | |
| Total biomass | − 0.371 | − 0.103 | 0.502 | |
| Panicle harvest index | 0.313* | − 0.097 | 0.122* | |
| Seedling | Final germ. percent | 0.907* | 0.560* | 0.441* |
| Vigor rating | 0.025 | − 0.080 | 0.001 | |
| Seedling chlorophyll content | 0.005 | 0.030 | − 0.007 | |
| Seedling biomass | 0.027 | − 0.038 | 0.011 | |
| Anthesis chlorophyll content | 0.010 | − 0.016 | 0.000 | |
| R-squared | 0.941 | 0.972 | 0.977 |
*Indicates parameter’s significant (p ≤ 0.05) unique contribution to prediction of grain yield.