Tomato has been extensively bred due to its short duration, easy cultivation, and large number of seeds per fruit. Breeding objectives include earliness, increased yield, fruit quality traits like size, color, and disease/stress resistance. Common breeding methods are introduction, pure line selection, pedigree, backcrossing, and heterosis breeding. Interspecific hybridization utilizes wild relatives for traits like disease resistance. New varieties have been developed with resistance to important diseases like bacterial wilt, nematodes, and viruses. Processing varieties have traits like uniform color, shape, acidity, and crack resistance.