บทคัดย่องานวิจัย

หมวดหมู่ : ฐานข้อมูลงานวิจัย

Quality growth conditions and post-harvest quality of tomato: the role of the xylem.

Van leperen W., Van Meeteren U.

5th International Postharvest Symposium . Volume of Abstract . Verona, Italy 6-11 June 2004, p.87

2004

บทคัดย่อ

Quality growth conditions and post-harvest quality of tomato: the role of the xylem. Quality of fresh tomato fruits is basically determined during growth of the fruits o­n the plant.It is commonly known that factors such as greenhouse climate, irrigation strategy and water quality can largely influence fruit production and quality.

Import of water, nutrients and assimilates from other parts of the plant largely determine fruit growth.Previous research has shown that during fruit development 90% of all water entering the fruit is transported via the phloem.Water import via the xylem seems to cease after maximal growth rate of the fruit has be reached: 25 days after anthesis (DAA).This is remarkable because the hydraulic resistance of the xylem usually is much smaller than that of the phloem.It seems therefore logical to assume that somewhere along the xylem transport path between shoot and fruits a large hydraulic resistance exists.However, restricting water import via the xylem also limits the import of calcium which can cause local calcium deficiency in fruits and concomitantly blossom-end rot, a major quality problem.

In present research we investigated the xylem connection between plant and fruit during fruit development and its possible role o­n fruit water relationships.Special attention has been paid to the knuckle, a structure which is usually found midway along the pedicel connecting an individual fruit to the truss.These knuckles contain a future abscission zone which might cause a major hydraulic resistance for xylem water transport.Knuckle containing and knuckle-less cultivars are compared and impact of measured hydraulic resistances o­n xylem water transport between plant and fruit are discussed.