Abstract: Freezing injury is one of the serious disasters in winter wheat production in North China. Because of its accumulative and latent characters, the early diagnosis and warning is most important for the prevention of freezing injury. Since the early 1980s, joint monitoring of freezing injury of winter wheat in North China is a creative work of protecting wheat seedlings.The theoretical basis of monitoring was established by research work on ecological types, indices and mechanism of fneezing injury, cold resistance, and its affect factors, anatomical characters and sequential effects of freezing injury. The methodological system was progresivcly formed and completed by combining methods of laboratory experiment, agronomical investigation and agrometeorological observation.The successful work of monitoring freezing injury has partly changed the passive situation in which people can not distinguish injury quickly and correctly, and the remedial chances were often lost. Recent years, the network of monitoring has been able to provide early accurate diagnosis and prediction of freezing injury of different areas, and to make feasible suggestions of remedial measures. Peasants have now got great benifit from this work in winter wheat production.

Key words: Wheat, Monitoring of freezing injury