Abstract:Cold sources of wheat are a kind of cold temperature-contributing wheat materials that has a strong temperature-decreasing effect, and when recipient materials receive gametes from the sources, their offspring will generally appear to have a decreased canopy temperature and some of them will change their temperature type from the types other than cold type to the cold type in offspring; moreover, cold type wheat has such characters as superior metabolic functions. Hence, cold sources of wheat not only play an important inducing role in the birth of cold type wheat but also much better help wheat achieve high and stable yield. Cold sources of wheat were planted under different meteorological conditions to study the variations of their kernel qualities. The study showed that the average weighted variation grade of 17 seed quality characters was 1.9877 for the cold sources and 2.8171 for other wheat types not belonging to cold sources and then the kernel qualities of the cold sources obviously slightly varied and remained rather stable compared with those of the other wheat types not belonging to cold sources. These smaller seed quality variations of the cold sources were closely correlated with small variations of the contents of protein and starch as well as their components and proportions between these contents during the seed formation process. Because cold sources of wheat are characterized by small seed quality variations, this character is easy to express in the cold type offspring in their hybridization, and accordingly favorable quality characters of cold type wheat can be repeatedly reproduced in production, which further endows cold type wheat making for high and stable yield with high-quality and stable-quality characters and finally greatly boosts wheat production, which is of great importance.