Figure 1.

Impacts of low-temperature stress on two winter wheat cultivars, XM and YN (XM: XinMai–Cold Sensitive and YN: YanNong–Cold Tolerant), is shown with the damage induced by cold stress, as compared with control (CK). Wheat cultivars with treatments (A) XMT2D4 [T2 = 4°C, D4 = 12 h/3 d], (B) YNT2D4 [T2 = 4°C, D4 = 12 h/3 d], (C) XMT6D4 [T6 = −4°C, D4 =12 h/3 d], and (D) YNT6D4 [T6 =-4°C, D4 = 12 h/3 d) has clearly exhibited the damage induced by cold stress, as compared with control (CK) treatments of XM and YN. Growth Conditions: Experiment grown under field conditions, before the heading stage shifted to the controlled chamber (Humidity: 70%, *Light intensity: 0 μmol·m⁻²·s⁻¹) for 3 days (4 h/day, Midnight: 12:00 a.m.−4:00 a.m.) for low-temperature treatments, then shifted back to field conditions. Photos were taken before the flowering stage; extracted leaves are flag/2nd leaf. *In this experiment, in night-time, wheat plants subjected to cold stress, and light intensity set at 0 μmol·m⁻²·s⁻¹ because, in field conditions of Huanghuai (China), plants experience late spring cold stress after midnight. (Unpublished: Own Experiment).