Fig. 4. Observed main stem Haun Stage and values predicted by the Streck model for (a) ‘BR-IRGA 409’ rice grown in pots in five sowing dates [2 Sept. 2004 (DOY = 245), 7 Oct. 2004 (DOY = 280), 4 Nov. 2004 (DOY = 308), 3 Dec. 2004 (DOY = 337) and 2 Mar. 2005 (DOY = 61)] and for (b) ‘IRGA 421’ and (c) ‘EPAGRI 109’ rice grown in the paddy rice field in two sowing dates [13 Dec. 2006 (DOY = 347), and 16 Jan. 2007 (DOY = 16)]. Santa Maria, RS, Brazil, 2004–2007.