2. Materials and methods
Two experiments with six barley genotypes were conducted at Mt Pleasant Laboratories (41°28’S, 147°08’E) in Launceston, Tasmania during 2019. Genotypes included four commercial varieties: Macquarie, Franklin, Planet, Westminster, a backcross line, Macquarie+ (Macquarie/TAM407227//Macquarie), and a double haploid line from the cross of TAM407227/Franklin, TAMF169 (Table 1).
For experiment 1, seeds were sown in six rows in stainless steel tanks (200 cm x·100 cm x 45 cm) filled with sandy loam soil with and bottom of each tank contained 50 mm coarse gravel overlaid with drainage matting. Each row was sown with 30 seeds on 30 May 2019. Each of the three blocks were randomised with one plot of each treatment (three plots per block) three replications. Plants were fertilised with 24 kg/ha of YaraMila Complex (12%N:11%P2O5:18% K2O, Yara Company). During the growth periods, all treatments were topdressed with equal amounts of 50 kg/ha of YaraMila Complex at jointing (GS32) and booting (GS45), respectively. No signs of nutrient deficiencies were observed.
Experiment 2 was conducted in a field screening facility with a waterlogging controlling system. Each genotype was sown in 1.2 m x 2 m plots with a 1.2 m row spacing of 20 cm and 30 seeds per row. The controls were sown in well drained beds. Four replicates were applied for both waterlogging treatment and controls. The trial was sown on 28th April 2019. The waterlogging treatment began at Zadoks stage 12.5 and continued for two months. All treatments were topdressed with equal amounts of 50 kg/ha of YaraMila Complex at jointing (GS32) and booting (GS45), respectively.