In both years, grain protein concentration was significantly increased
at TOS2 (17%, 16%) than at TOS1 (12%, 13%). On an average,
protein concentration increased by 40% and 17% at TOS2 in 2008
and 2009, respectively (Fig. 1). Such increases in protein concentration
in TOS2 could be partly due to a lower grain yield which was
mainly due to higher temperatures and water stress experienced
in the later stages of plant development (Table 1). Increased grain
protein synthesis at high temperature (30–35 C) has been documented
elsewhere (Balla, Karsai, & Veisz, 2009; Panozzo & Eagles,
2000).