Abstract: Anti-MAI1 gene was translated into melon fruits by ovary injection. PCR amp lification and
Southern Blot analysis showed that two transgenic plantswere obtained from 330 melon p lants, transformation
frequency was about 0.6% , and each transgenic plant had double copies of anti-MAI1 gene. The T0 genera
tion transgenic melon plants had lower growth ability, and the fruitswere 30% smaller than control fruits, but
had 52% more soluble sugar than control fruits. There was no gene lost in T0
-1 progeny with the analysis of
PCR and PCR - Southern blot. Also, transgenic p lants of T1 generation had weaker growth ability than control
plants. Each T1 generation transgenic fruit had higher soluble sugar and sucrose concentrations but had lower
levels of acid invertase in ripe fruit than control fruits. These results suggest that acid invertase control sugar
composition in melon fruit and this change in composition contributes to alterations in fruit size and p lants
growth ability.

Key words: Melon, Transgenic, PCR, Acid invertase