Table 1.

Details of the phenological, agronomic, and climatological data of the experiment, together with a summary of linear regression of selected variables over time (regression on year)

	1958–2012								1972–2012
	Mean	SD	Min	Max	b	SE	R 2	P	b	SE	R 2a	P a
Sowing	−97 (Sep. 25)	4	−105	−87	0.087	0.030	13.6	0.006	0.225	0.085	20.8	0.012
Emergence	−85 (Oct. 7)	5	−93	−72	0.021	0.044	0.4	0.639	0.358	0.114	20.7	0.003
Shooting	76 (Mar. 16)	9	59	100	−0.167	0.079	7.8	0.039	0.215	0.174	5.3	0.224
Heading	108 (Apr. 18)	8	93	123	−0.127	0.069	6.0	0.071	−0.104	0.176	17.8	0.556
First flower	133 (May 13)	5	118	149	−0.064	0.046	3.5	0.169	−0.152	0.103	33.2	0.267
Full flower	149 (May 29)	10	127	167	−0.363	0.065	37.1	<0.001	−0.398	0.131	57.4	0.004
Harvest	208 (Jul. 27)	6	195	221	0.138	0.050	12.4	0.008	0.251	0.140	10.0	0.081
Yield (t/ha)	4.20	1.36	1.55	6.57	0.064	0.008	56.9	<0.001	0.007	0.019	62.5	0.720
Density (plants/m2)	383	85	242	551	4.39	0.89	38.3	<0.001	−1.27	1.12	69.0	0.264
Grains/ear	34	6	17	52	0.163	0.080	9.6	0.049	0.260	0.142	11.2	0.074
Annual mean temperature (°C)	8.3	1.0	6.6	10.3	0.041	0.007	40.0	<0.001
Annual total precipitation mm	605	131	313	841	3.58	1.11	17.1	0.002

b represents the per year trend which is presented together with its standard error, % variance accounted for (R ²), and an indication of statistical significance (P). Phenological and yield data for 1958–2012, other agronomic data for 1972–2012, and climatological data for 1961–2012

The regression models for 1972–2012 involve just a single variety in use and include a dummy variable (see text for details)

^a R ² indicates the overall model, but P just the significance of the trend through time