الفهرس 
introductionOnly 14 pages are availabe for public view
 |  | from | 80 |  |  |
| | | from | 80 | | |
Abstract
Guava Psidium guajava, Lin&’ is probably the most important fruit of the family ‘ Myrtaceae ‘.In Egypt, the total area under guava plantation reached about 29775 feddaiis with total fruit production of 23330 metric tons, according to the latest statistics of the Ministry of Agriculture (1992).
The great importance of guava lies in its fruit which is considered as the cheapest and richest source of vitamin c, since it contains four to ten times that of orange fruits (Coit, 1945 and Godston and Chanin, 1946). Besides, the fruits contain small amounts of vitamins A, B and B2 with 11.6% carbohydrates, 0.6 oils and 1% protein (Godston and Chanin, 1946). Moreover, fruits are consumed either fresh or in jelly, jam and juice products Popenoe, 1932). On the other hand, guava fruits ripen inbetween seasons, where other fruits are scarce.
As for horticulturists, guava is admired as being o low cultural requirements Popenoe, 1932). For instance, the trees are successfully grown in various kinds of soil; sand, or very light sandy; rich or poor; dçj or moist (Bally, 1960). Meanwhile, trees yield at a time when markets are nearly lacking from other fruits.
No doubt that, the commercial value of guava is determined by the quantity and quality of produced fruits. In this concern, the yield of guava trees is greatly affected by two waves of fruit dropping namely June DROP and pre-harvest drop. On the other hand, number of seeds per fruit adversely affect the quality of guava fruits. Therefore, this investigation was initiated as a trial to improve yield and quality of guava fruits through decreasing fruit dropping and reducing the number of seeds per fruit via spraying guava trees with some growth regulators i.e gibberellin and Naphthalene acetic acid as well as some organic acids i.e Folic acid and Argenine.