Oranges Essays - Orange, Tropical Agriculture, Citrus,

Oranges All citrus trees belong to the single genus Citrus and remain almost entirely interfertile. This means that there is only one superspecies that includes grapefruits, lemons, limes, oranges, and various other types and hybrids.[9] As the interfertility of oranges and other citrus has produced numerous hybrids, bud unions, and cultivars, their taxonomy is fairly controversial, confusing or inconsistent.[3][6] The fruit of any citrus tree is considered a hesperidium (a kind of modified berry) because it has numerous seeds, is fleshy and soft, derives from a single ovary and is covered by a rind originated by a rugged thickening of the ovary wall.[10][11] Different names have been given to the many varieties of the genus. Orange applies primarily to the sweet orange Citrus sinensis (L.) Osbeck. The orange tree is an evergreen, flowering tree, with an average height of 9 to 10 m (30 to 33 ft), although some very old specimens can reach 15 m (49 ft).[12] Its oval leaves, alternately arranged, are 4 to 10 cm (1.6 to 3.9 in) long and have crenulate margins.[13] Although the sweet orange presents different sizes and shapes varying from spherical to oblong, it generally has ten segments (carpels) inside, and contains up to six seeds (or pips)[14] and a porous white tissue called pith or, more properly, mesocarp or albedolines its rind.[15] When unripe, the fruit is green. The grainy irregular rind of the ripe fruit can range from bright orange to yellow-orange, but frequently retains green patches or, under warm climate conditions, remains entirely green. Like all other citrus fruits, the sweet orange is non-climacteric. The Citrus sinensis is subdivided into four classes with distinct characteristics: common oranges, blood or pigmented oranges, navel oranges, and acidless oranges.[