Final diagnosis


Large non-parasitic pivot and Sphingomonas suberifaciens

Many plants distributed in 1 to 2 rows show lower growth compared to surrounding plants; it is an attack of <i> Sphingomonas suberifaciens </i>. <b> Distribution in rows </b>
Some salads show a reduced size. <i> <b> Sphingomonas suberifaciens </i> </b> ("corky root")
The root system of torn lettuce has numerous lesions more or less corky. <i> <b> Sphingomonas suberifaciens </i> </b> ("corky root")
In addition, many roots have turned yellow and brown; corky streaks and sleeves are visible in places. <i> <b> Sphingomonas suberifaciens </i> </b> ("corky root")
The taproot may be enlarged, strongly suberized and sometimes streaked with large corky streaks. <i> <b> Sphingomonas suberifaciens </i> </b> ("corky root")
In some affected areas, the roots, brown and superficially corky, show varying degrees of longitudinal bursting. <i> <b> Sphingomonas suberifaciens </i> </b> ("corky root")
We find the same type of symptoms on the pivot where a superficial suberization and cracks can be observed. <i> <b> Sphingomonas suberifaciens </i> </b> ("corky root")
In some cases, the taproot may swell and be virtually rootless. <i> <b> Sphingomonas suberifaciens </i> </b> ("corky root")
This root shows yellowish lesions gradually turning brown. <b> <i> Sphingomonas suberifaciens </i> </b> ("corky root")
The root system of this lettuce has numerous brown lesions which sometimes encircle certain roots over a considerable length. <i> <b> Sphingomonas suberifaciens </i> </b> ("corky root")