The study looked at how different ways of giving nutrients to peach trees affected the fruit quality. They compared using water with nutrients (fertirrigation) to regular fertilization and no fertilization. They found that the amount of nutrients affected the levels of certain acids and sugars in the fruits. In 1999, the fruits had different levels of sugars and acids depending on how they were fertilized. As the fruits ripened, the sugar content increased while some acids decreased. The control group (no fertilization or irrigation) had higher levels of acids and sugars in the fruits.