Thursday, June 16, 2016

Tomato Psyllids

picture of tomato psyllid adults and nymphs
Tomato psyllid adults and nymphs (Photo: NMSU-PDC)
Featured Diagnosis: Tomato (Potato) Psyllids - Hemiptera, Psyllidae, Bactericera cockerelli.

These tiny insects will attack a wide range of hosts but prefer solanaceous plants like tomato, potato, peppers, and eggplant. Published reports indicate that yellow pear tomato is especially susceptible to tomato (potato) psyllids. The infestation pictured here began on a yellow pear tomato and quickly spread to several other tomato varieties. Psyllid eggs are laid on stalks on the under side of the leaves. Nymphs hatch from the eggs and are flattened, oval and yellowish green to orange with red eyes and three pairs of legs. They develop through five instars before becoming adults. Adult psyllids are ~3mm long have white to yellowish markings and clear wings. Psyllids feed most often on the underside of the leaves. While feeding, the insect injects a toxin into the plant. The toxin causes a variety of symptoms which collectively are commonly referred to as “psyllid yellows.” These symptoms include stunting, yellowing, and curling of the leaves. Plants damaged by psyllids may produce little or no fruit. Fruit that is produced is often small, even in large-fruited varieties, and of poor quality. Small seedlings or transplants may be killed by the insect. 

A composite photo of tomato plants infested with small insects called psyllids
Tomato psyllids on leaves and stems of tomato plants (Photos: NMSU-PDC)

tomato plant in a pot with psyllid insects feeding on it
Tomato psyllid infested tomato plant (Photo: NMSU-PDC)

Wednesday, June 15, 2016

Tomato Spotted Wilt Virus on Dahlia

Dahlia plant with yellow flecking on the leaves caused by a virus
Tomato Spotted Wilt Virus on dahlia - note
the yellow flecking near the tip of the leaf
(Photo: NMSU-PDC)
Featured Diagnosis: Tomato Spotted Wilt Virus is a common virus with the ability to cause disease on a wide range of hosts. In New Mexico, it is often found on peppers and tomatoes. Recently, the virus was identified on dahlia. Dahlia is a known host for this pathogen, but this is the first report of the disease on dahlia in New Mexico. The symptoms on the dahlia samples submitted to the NMSU Plant Diagnostic Clinic were subtle; a yellow flecking on some of the leaves.