บทคัดย่องานวิจัย

หมวดหมู่ : ฐานข้อมูลงานวิจัย

Effect of ethylene treatment on fruit firmness and polygalacturonase activity in stony hard peach.

Hayama H., Ito A., Kashimura Y.

5th International Postharvest Symposium . Volume of Abstract . Verona, Italy 6-11 June 2004. page 9

2004

บทคัดย่อ

Effect of ethylene treatment on fruit firmness and polygalacturonase activity in stony hard peach. The texture of peach fruit is the basis for the melting-flesh (MF) and no melting-flesh (NMF) classifications.MF fruit is the common table peach that loses firmness rapidly during ripening, while NMF lacks the rapid loss of firmness during the late ripening stages and is commonly used for processing.The rapid loss of firmness in MF fruit has been shown to be related to the activity of endopolygalacturonase (endoPG).Levels of endoPG activity are greatly reduced in NMF peaches compared to MF fruit, while the levels of exopolygalacturonase (exoPG) activity were similar for the two fruit type.Stony hard-flesh is another important flesh texture trait that is characterized by low ethylene production in the fruit without the loss of firmness during ripening.However, ethylene treatment causes stony hard-fruit to lose firmness and soften to a melting-like texture.

In this study, we analyzed the enzymatic activity of endePG and exoPG in stony hard peach cv. ‘Manami’ with and without ethylene treatment to confirm the role of PGs in peach fruit softening.The ‘Manami’ fruit without ethylene treatment remained firm during a 5-day treatment period, while the treated ‘Manami’ fruit began to lose firmness after 24 h of ethylene treatment and then rapidly softened in 2 or 3 days.The endoPG and exoPG activity began to increase in ethylene treated ‘Manami’ fruit after 24 h of treatment and the increase was closely related with the rapid loss of fruit firmness.In ‘Manami’ fruit without ethylene treatment, the activity levels of both endoPG and exoPG were low and remained unchange during ripening.These results indicated that both endo-and exo-PGs were induced by ethylene treatment in ‘Manami’ fruit.This increase in the activity of PGs may be related to peach fruit softening.