Table 4.
Deconstruction of genotype-by-tillage interactions including effects of experimental terms on root angle (RA) in year 1, crown root number (CRN) in both years and nodal root number (NRN) in year 2 among 20 wheat varieties at the Sonning site analysed separately for two tillage levels. CT = conventional tillage and SNI = shallow non-inversion tillage. Effect values for size of each term include F-statistic for RA and Wald statistic/d.f. for CRN and NRN. Asterisks indicate significance level: *** = p < 0.001, ** = p < 0.01, * = p < 0.05. d.f. = degrees of freedom.
| Trait | Term | d.f. | CT | SNI |
|---|---|---|---|---|
| RA in Year 1 | ||||
| Genotype | 19 | 3.65*** | 1.85* | |
| CRN in both years | ||||
| Genotype | 19 | 1.93** | 3.23*** | |
| NRN in Year 2 | ||||
| Genotype | 19 | 4.48*** | 5.24*** | |