Thus, crop
improvement in the disease resistance of rice requires new biotechnological
tools. Recent advancements in the crop improvement
using classical induction mutagenesis have been well
established with many newly developed promising varieties created
worldwide using both physical and chemical mutagens. Since
the disease stresses have lowered rice productivity in Thailand,
breeding of disease resistant genotypes using mutation induction
assisting improvement in rice has been carried out. Many types
of physical mutagenic sources, for example, X-ray, gamma-ray, ultra-
violet light irradiation, neutron, and ion beam, have been
developed and applied to crop mutation. In application of ion