X-disease

In making a diagnosis of X-disease, one must consider the insidious onset, slow course, and number of animals affected.

At the time of its first occurrence, nothing was known about the cause of X-disease or whether it could be treated and cured.

Crankcase oils may contain chlorinated naphthalenes, which have been reported to contribute to "X-disease" (hyperkeratosis) in cattle.

For example, a 1940s claim attributed to DDT, without a shred of evidence, a mysterious cattle disease known as X-disease (discussed further in appendix 4).

Transmission of X-disease was more erratic with peach than with chokecherry buds, possibly because only low titers of the X-disease mycoplasma-like organisms (MLO) are present in infected peach trees during most of the year.

Studies of the phytoplasma associated with choke cherry X-disease in North Dakota.

A number of other yellows diseases of trees are of major importance throughout the world either because of local impact or widespread distribution. Among these are Prunus X-disease, pear decline, elm phloem necrosis, apple proliferation, the witches'—broom diseases of paulownia and jujube, and the greening and stubborn diseases of citrus.