Pistachios are a nut that grows on trees. At maturity, the nut's shell is partially cracked, and the consumer cracks it the rest of the way before eating. Some problems can arise with pistachios in the growing and processing procedures.

 Pistachio Disorders

• Pistachios have physiological disorders that affect the way that they look. They may grow too small or may be shrunken. Rancidification is a problem that involves the shells becoming stained. The nuts are not picked until the shell splits, so if this takes too long, the fruit can go bad. Sometimes the shells develop without any nuts, due to unsuccessful fertilization.

Insect Diseases

• Insects cause diseases on both the exterior and interior of the nut. The exterior can experience discolorations, but the nut will be safe. However, if insects are able to get through the shell, the nut will become diseased. The insect that causes the biggest problem to pistachios is the navel orange worm. They cause a problem when the nuts are on the tree, not when they are being stored. Some of these diseases can be transferred to other nuts and parts of the tree, which is of great concern to nut producers.

Fungal Diseases

• Fungal diseases are spread by insect infestation and infection, but they may also be exacerbated by storage issues. When insects feed on young nuts, which are particularly susceptible, the infestation may not be caught until the nut is mature. Storing pistachios in a clean, dry area will ensure that they do not develop a fungal disease as a result of storage.

List of pistachios diseases(Pistacia vera).

Fungal diseases

Diseases of uncertain cause

Miscellaneous diseases and disorders