From the Super Mario Wiki
Berries (also referred to as Apples and Yoshi Fruit) are fruit found in Dinosaur Land, but have also made appearances elsewhere. Yoshis can eat them and, depending on the color of the berry, get some kind of item.
Super Mario series
Super Mario World
In Super Mario World, Yoshis can eat berries for a value of one coin. Three kinds of berries can be found in this game. Red-colored berries give Yoshis a Super Mushroom if he ate ten in the same stage (in the Super Mario Advance 2 version, a Red Yoshi will get a Fire Flower, Blue will get a Cape Feather, and Yellow will get a Starman). Pink berries give a coin throwing cloud if he ate two in the same stage. The cloud would give a 1-Up Mushroom if he collected all the coins. The rare green berries, found only in Funky (and the intro level at the start of the game), add 20 seconds to the timer.
New Super Mario Bros. Wii
Red Berries also appear in New Super Mario Bros. Wii, where they serve the same role. Every five Berries Yoshi eats makes him produce an item. The item that Yoshi yields depends on the power-up that Mario is using when Yoshi eats five berries.
Super Mario Galaxy 2
The red Berries reappear in Super Mario Galaxy 2. This game's manual simply refers to them as Fruits. Yoshi can eat these to earn Star Bits. If ten berries are eaten, one life will be given. Super Mario Galaxy 2 also features large golden berries that Yoshi has to hold on to it with his tongue for a few seconds before he can eat it. It gives a Launch Star and five Star Bits when Yoshi eats it. This game also has a power-up called a Bulb Berry. When Yoshi eats a Bulb Berry he glows and can illuminate otherwise invisible ground.
New Super Mario Bros. U
Paper Mario series
In Paper Mario, there are several types of Berries in Flower Fields. Red Berries, Blue Berries, Yellow Berries, Bubble Berries, and Crystal Berries all appear in the game. The Crystal Berry is a key item, and the other four are regular items.
Strawberries also appear in the Peach segment between chapters 4 and 5 (when Peach has to bake a cake for Gourmet Guy).