h.gonzalez@cgiar.org, m.ibba@cgiar.org, l.crespo@cgiar.org, c.velazquez@cgiar.org, n.h.espinosa@cgiar.org, diaz.huizar@inifap.gob.mx

Wheat cultivation and trade form a significant part of the global economy. As one of the most widely cultivated cereal grains worldwide, its production and trade contribute to the livelihoods of millions of people involved in farming, processing, and distribution. Wheat plays a crucial role in ensuring food security for many nations. Therefore, ensuring adequate wheat grain and processing quality under the current climate change scenario is of utmost importance and a key target for wheat improvement.

In the present study, the end-use quality of a set of 271 spring bread wheat elite lines grown under optimal conditions, reduced irrigation, and late heat stress during the 2021-2022 cycle was analyzed.

The parameters most influenced by the abiotic stresses were thousand kernel weight (TKW) (r²=0.703), followed by test weight (TESWT) (r²=0.61), grain protein content (GRNPRO) (r²=0.54), and bread loaf volume (LOFVOL) (r²=0.50). In the detailed analysis by environment, it was found that for the full irrigation environment, both test weight (81.5 kg/hl) and thousand kernel weight (53.0 g) yielded the highest values, while the lines grown under reduced irrigation exhibited the lowest grain quality, with average TESTWT values of 77.6 kg/hl and TKW values of 42.1 g.

Regarding grain and flour protein content (FLRPRO), the lines grown under late heat stress presented the highest values (GRNPRO = 14.4%; FLRPRO = 12.0%), followed by those harvested under reduced irrigation (GRNPRO = 14.0%; FLRPRO = 11.1%).

Similarly to protein content, the overall gluten strength and elasticity of the analyzed lines increased under reduced irrigation (Alveograph W = 443 x 10⁻⁴ J; Alveograph Ie = 62.1%) and late heat stress (Alveograph W = 394 x 10⁻⁴ J; Alveograph Ie = 62.5%) compared to the values obtained under optimal conditions (Alveograph W = 253 x 10⁻⁴ J; Alveograph Ie = 45.8%).

An average increase of 80 cm³ was also observed in the loaf volumes of the lines grown under abiotic stress compared to those grown under optimal conditions.

Based on these results, it is clear that the grain physical quality of wheat grown under stress is reduced. However, it is evident that these conditions are generally associated with an increase in bread-making quality. Further studies across different years and using different germplasm will be required to confirm this trend and to support the development of high-quality and climate-resilient wheat.