Abstract: 12 progenies and 138 varieties of 4 species of pears were used for discussing the inheritance tendency of main characters of pears. The results were as following : The sugar content of the fruits of cultivated varieties was between 6% and 9 % , the average was 7. 39 % , and it was on the moderate low side . The sugar content of the fruits of the progenies was quantitative character and presented normal distribution. The total sugar content of the samples were between 6% and 8 % , The average was 7. 848 % , and the average inheritance of transfer ability was 90. 8%. The acid contents of cultivated varieties were from 0. 08 % to 0. 74% , the average was 0. 238%. The acid content of the fruits of pear hybrid progenies was the quantitative character , and its average inheritance of transfer ability was 69. 2%. There were 16 kinds of compounds including 5 kinds of ester , 8 kinds of alcohols , ethylene , aldehyde , and acetone as the volatile substance of the fruits of the pear progenies. Amyl alcohol was found in the fruits of pear hybrid progenies , which had not been in the parents. The flesh quality of pear was qualitative character. Comparing to soft-flesh , crisp-flesh was dominant . The fruit spot of pear hybrid progenies tended to get larger and thinner ; the fruit stalk tended to get longer ; and the fruit juice tended to get less ; and the thickness of the fruit coat was equal to the mid-parent value.

Key words: Pear, Fruit characters, Inheritance tendency