Study of soft wheat by the canopy temperature depression under Altai territory conditions

Abstract

Results of research in the field of wheat drought tolerance breeding by infrared thermometry method are presented. It is noted that in Russia this method is still not widespread. The parameter Canopy temperature depression (CTD) among collection samples of spring wheat was studied. The experiment was conducted in the Altai Territory in 2019-2021. Yield, elements of its structure and the duration of seedling – heading period were studied in 55 varieties of spring soft wheat. The canopy temperature was measured with a portable infrared thermometer. CTD was defined as the difference between the air temperature and the canopy temperature. The average CTD across the varieties was 6.1, -0.8, and 2.6 °C in 2019, 2020, and 2021, respectively. Significant influence on the variability of this trait had both the factor of year and genotype. During the three years of the study CTD had a stable reliable relationship with the duration of the seedling - heading period (r = 0.27- 0.37), and in two of the three years - with the yield (r = 0.32 and 0.60). In the driest year (2020), CTD was positively correlated not only with the yield structure elements (r = 0.17-0.48), but also with the plant height (r = 0.55). The highest average CTD value for three years was recorded for Altayskaya zhnica (3.5 °C), Stepnaya niva (3.6 °C), Burlak (3.8 °C), Obskaya 2 (3.9 °C), Lutescens 360/96, Merzana, Alexander (4.0 °C) and Lutescens 208/08-4 (4.4 °C) cultivars.