Chili and Whangkeumbae pear were used to examine the fruit firmness, ethylene production rate, soluble pectin content and the expression patterns of seven PcEXPA genes in this paper.During the postharvest storage, the fruit firmness of both Chili and Whangkeumbae pear were decreased, while Chili fruit maintained higher fruit firmness than Whangkeumbae fruit.The soluble pectin content of Whangkeumbae pear was higher than that of Chili pear.The expression of seven PcEXPA genes showed that the expression of PcEXPA2 was consistent with the changes of fruit firmness and the ethylene production rate, and were down-regulated by 1-MCP treatment in the two varieties of pear. PcEXPA2 was closely related to the fruit softening of Chili and Whangkeumbae pear.
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