Global warming is reducing the tillering capacity and grain yield of wheat in Yaqui Valley, Mexico

Abstract

The effect of temperature variations recorded in eight meteorological stations in Yaqui Valley, Sonora, Mexico, on the tillering capacity and grain yield of wheat variety CIRNO C2008 in the growing cycles December 2016-May 2017 and December 2017-May 2018 was studied. In one of the sites, the crop canopy temperature was increased by +2°C with a T-FACE system (warming) based on the temperature recorded in the nearest meteorological station. With the two experimental variants, the abscisic (ABA) and gibberellic (GA) acid hormones were determined during tillering (initial tillering: 30 d after emergence and final tillering: 45 d after emergence) to explain their contribution to the tillering capacity response. A temperature variability of 1°C was observed in the cycle December 2017- May 2018, as compared to the previous cycle and between the evaluated sites. As a result of the temperature increase effect, the tiller number was significantly reduced. The experimental warming caused a highly significant decrease in the ABA content and an increase in the GA. The temperature variation found in Yaqui Valley had a negative and significant correlation with the grain yield in both experiment crop cycles, which demonstrated that global warming is reducing the tillering capacity and grain yield of wheat in Yaqui Valley.