Effects of grafting on free fatty acid contents and related synthetic enzyme activities in peel and flesh tissues of oriental sweet melon during the different development period

In this experiment, white seed pumpkin 'Shengzhen No. 1' was used as rootstock for the oriental sweet melon (Cucumis melo L.) 'Yumeiren'. The fruits of own-rooted melons were used as control. The objective of this experiment was to study the effects of grafting on the following parameters: content of free fatty acids and activities of synthetic enzymes (LOX, ADH, and AAT). These parameters were measured in the peel and flesh tissues of oriental sweet melon at different time-points. Due to grafting, the content of oleic acid and linolenic acid decreased in peel tissues of melons at early stages of maturity. Therefore, total contents of free fatty acids were lower than those of control. However, there was no significant difference in the content of three free fatty acids in flesh tissue; this content was lower than that in peel tissue. Due to grafting, enzymatic activities of ADH and AAT decreased in peel tissue of melons; however, these enzymes showed different activities in flesh tissues of melons subjected to grafting. Nevertheless, there was no significant difference in enzymatic activities of flesh tissues; however, these activities were lower than that of peel tissue. These results indicate that free fatty acid content and related synthetic enzyme activities decreased when grafting was included in the cultivation of oriental sweet melons. Consequently, the aroma of these melons decreased due to grafting.