First report of stem and bulb nematode Ditylenchus dipsaci on garlic in New Mexico.
In May 2005, garlic plants from a home garden in Dona Ana Co. were submitted to the Plant Diagnostic Clinic in New Mexico State University, Las Cruces, New Mexico, USA. The grower reported poor growth in ∼30% of 1 200 plant originating from seeds purchased in sourthern New Mexico. Early symptoms included chlorosis, wilting, and poor root and bulb development. As the disease progressed, root turned brown, were easily separated from the bulb, and older foliage had collapsed and turned straw coloured. Microscopic examination showed large number of nematodes present in symptomatic garlic plants. Based on symptoms, morphological characteristics and ITS-1 sequence data, the nematodes were identified as Ditylenchus dipsaci. This is thought to be the first report of D. dipsaci in New Mexico.