บทคัดย่องานวิจัย

หมวดหมู่ : ฐานข้อมูลงานวิจัย

Fruit abcission as related to fruit quality.

Ramina A.

5th International Postharvest Symposium . Volume of Abstract . Verona, Italy 6-11 June 2004. page 34

2004

บทคัดย่อ

Fruit abcission as related to fruit quality.  Many fruit species bear an abundance of flowers which produce a surplus of fruit that the tree is unable to support.In anticipation of this, the major fruit species developed an immature fruit physiological drop as self regulatory mechanism.From a horticultural point of view, this self regulation mechanism may be too strong or entirely insufficient.To overcome these shortcomings bioregulators are currently used.Knowing more precisely about molecular mechanism underlying natural fruitlet abscission would help in setting up more efficient control strategies.

In this context peach and apple fruitlets were assumed assumed as study models.Fruitlet abscission is a highly coordinated event.It involves multiple changes ion cell structure, metabolism and gene expression, leading to cell separation occurring in specific tissues designated as abscission zone (AZ).Anatomical, biochemical and molecular events associated with cell separation at fruit AZ level have been described.Increases of expression and activity of specific cell wall hydrolases, as well as other proteins as expansins, a metallothionein-like protein, and pathogenesis related (PR) proteins have been reported.

Ethylene and IAA regulate abscission.The general interaction between the two hormones is manifested in their antagonistic relationship, when the IAA status of the tissues controls its sensitivity to ethylene.On the other hand ethylene isa potent inhibitor of IAA, interfering with its polar transport.It has been demonstrated that the activation of fruit abscissionis preceded by the stimulation of ethylene biosynthesis and the up regulation of an ethylene specific receptor.At the moment efforts are made to sorted out additional abscission related genes that might be used for constructing molecular tools useful in screening new chemical thinners or in selecting self-thinning varieties.