Partial least squares (PLS) biplot of the number of locations and treatments with environmental and soil covariables on the performance of grain Zn concentration in HUW 234 wheat at four locations in the Eastern Gangetic Plains of South Asia (extracted from Crossa et al., 2010). Treatment explanations are available online. Sites: Pidk, Pidkhir; Ghur, Ghurahoopur; Bhad, Bhadawal; BHU, Banaras Hindu University. The 12 treatments are: (1) control; (2) soil- 25 kg ha–1; (3) soil- 50 kg ha–1; (4) foliar- 1.0 kg ha–1 at two stages (flag leaf emergence and anthesis); (5) foliar- 2.0 kg ha–1 at two stages; (6) foliar- 4.0 kg ha–1 at two stages; (7) soil (25 kg ha–1) + 2 foliar (2.0 kg ha–1); (8) soil (50 kg ha–1 ZnSO4) + 2 foliar (2.0 kg ha–1); (9) soil (0 kg) + 2 foliar (2.0 kg ha–1); (10) soil (25 kg) + 2 foliar (2.0 kg ha–1); (11) soil (50 kg) + 2 foliar (2.0 kg ha–1); (12) local farmers’ practice for Zn (5 kg ZnSO4 ha–1). Environmental and soil variables are: TMXBF: temperature maximum before flowering; TMXAF: temperature maximum after flowering; TMNBF: temperature minimum before flowering; TMNAF: temperature minimum after flowering; RHBF: relative humidity before flowering; RHAF: relative humidity after flowering; RBF: rainfall before flowering; RAF: rainfall after flowering; Zn_30: Zn concentration at 0–30-cm soil depth; Zn_60: Zn concentration at 30–60-cm soil depth; Fe_30: iron concentration at 0–30-cm soil depth; Fe_60: iron concentration at 30–60-cm soil depth.