Abstract: RNA-sequence and real-time quantitative polymerase chain reaction（PCR）technique （qRT-PCR）were used to identify the expression of key polygalacturonase（PG）genes involved in pectin degradation in kiwifruit，stored at room temperature at different time periods during storage. The expression pattern of 37 PG genes could be divided into 4 groups according to the RNA-sequence results of different samples stored at room temperature. For example，Achn325011，Achn240441，Achn071601 and Achn100411 genes present a peak expression at 2，4，6 and 8 days after harvest. Fourteen PG genes belonging to groups 1 and 4 were verified using the qRT-PCR as a decrease in fruit firmness on the 6 d after storage was observed. Among these PG genes，the expression of 4 genes was related to the fruit firmness change. Moreover，the expression of these 4 genes was also evaluated in kiwifruits treated with exogenous ethylene. The results of ethylene treatment showed that the expression of a single gene called Achn071601 was consistent with the fruit firmness change during the storage period. Therefore，Achn071601 should be considered as a key PG gene in kiwifruit.

Key words: kiwifruit, storage, RNA-seq, PG gene