Abstract: 【Objective】The purpose of the study was to analyze the chilling requirement and related gene expression during dormancy release of Queen Nina grape,so as to provide a theoretical reference for the introduction and promotion of Queen Nina grape in Guangxi grape producing areas and the study of its dormancy release mechanism.【Method】Three-year-old Queen Nina grapes were used as experimental materials,and the 0-7.2℃ estimation model was used. The post-harvest pruning branches were treated at(4±1)℃ for four different chilling treatment times of 0,312,408 and 504 h. The germination rate of branches treated with different chilling treatment times was calculated by hydroponic investigation,and the range of chilling requirement was determined by comparing the germination rate of branches treated with 3% hydrogen cyanamide dormancy breaker. The contents of total soluble sugar and starch in branches of each treatment were determined. The relative expression of five key genes for dormancy release was determined by real-time fluorescence quantitative PCR.【Result】After 312 h of chilling treatment,the germination rate of Nina Queen grape was higher than 50% after 4 weeks of hydroponic culture,and there was no significant difference in the germination rate between all of them and that of the same chilling treatment sampled and then treated with hydrogen cyanamide(P>0.05). In addition, the chilling accumulation hours of 0~7.2℃ under natural conditions before sampling were 37 h. Therefore,by adding the chilling treatment time to the natural accumulation of chilling hours,the chilling requirement could be estimated to be<349 h. During the dormancy release process of Queen Nina grape buds,the starch content in the branches significantly decreased(P<0.05,the same below),and starch was converted into soluble sugars,with a significant increase in soluble sugar content. Compared with those without chilling treatment(0 h),the relative expression of the four key genes,including abscisic acid(ABA)synthase gene VvNCED1,ABA degrading enzyme gene VvA8H4,ABA regulated callose synthase gene VvCALS1 and callose hydrolase gene VvGLU1,significantly increased in Queen Nina buds after chilling treatment,while the relative expression of ABA synthase gene VvXERICO significantly decreased.【Conclusion】Chilling treatment can release bud dormancy by reducing starch content,increasing the total soluble sugar content in the branches of Queen Nina grape,and further up-regulating the expression of ABA degrading enzyme genes and callose hydrolase genes in the buds of the grape. Queen Nina grape is a low chilling requirement variety,which is suitable for planting in Guangxi grape producing area.