Environment also plays a role in the expression of quantitative traits. The primary effect is to modify the genotypic potential. The table below gives the yields for three durum wheat cultivars grown at one location of 10 years. The genotype is fixed for each of the cultivars. Therefore, the only effect that is causing the differences in yield levels is the environments.
| Genotype | |||
|---|---|---|---|
| Year | Roughrider | Seward | Agassiz |
|
1986 |
47.9 |
55.9 |
47.5 |
| 1987 |
63.8 |
72.5 |
59.5 |
| 1988 |
23.1 |
25.7 |
28.4 |
| 1989 |
61.6 |
66.5 |
60.5 |
| 1990 |
0.0 |
0.0 |
0.0 |
| 1991 |
60.3 |
71.0 |
55.4 |
| 1992 |
46.6 |
49.0 |
41.5 |
| 1993 |
58.2 |
62.9 |
48.8 |
| 1994 |
41.7 |
53.2 |
39.8 |
| 1995 |
53.1 |
65.1 |
53.5 |
