The genus Ditylenchus has been divided into 2 groups: the Ditylenchus triformis-group, and the Ditylenchus dipsaci-group based on morphological and biological characters. A total of 18 populations belong to 5 species of Ditylenchus was studied: Ditylenchus africanus, Ditylenchus destructor, Ditylenchus myceliophagus and dipsaci, Ditylenchus weischeri, the first 3 belong to the Ditylenchus trifo...

The alfalfa race of Ditylenchus dipsaci parasitized and caused characteristic symptoms on nonhost seedlings of sweet clover, onion, tomato, sugarbeet, and wheat in controlled growth-chamber studies. Although the nematode was unable to reproduce on any of the cultivars, it caused plant mortality ranging from 20% on sugarbeet and tomato to 100% on onion.

The holotype of Chitinotylenchus paragracilis (Micoletzky, 1922) is redescribed and illustrated. Chitinotylenchus is proposed as a synonym of Ditylenchus Filipjev, 1936 and C. paragracilis as Ditylenchus paragracilis (Micoletzky, 1922) new comb. The four other species in the genus Chitinotylenchus are considered species inquirendae.

Saiphos equalis, a semi-fossorial scincid lizard from south-eastern Australia, is one of only three reptile species world-wide that are known to display geographic variation in reproductive mode. Uniquely, Saiphos equalis includes populations with three reproductive modes: oviparous with long (15-day) incubation periods; oviparous with short (5-day) incubation periods; and viviparous (0-day inc...

Ditylenchus dipsaci (Kühn) Filipjev is a serious pest of commercial daffodil (Narcissus sp.) in northern California. The control measures practiced by growers in recent years are postharvest treatment of planting bulbs for 3 hours in a 1% solution of formalin at 44 C combined with preplant soil fumigation with 1,3-dicbloropropene and (or) at-planting applications of phorate. In field trials, se...

Ditylenchus dipsaci larvae survived in soil without a host plant for at least 242 days when held at 15 C and 21 C. Larvae held at 15 C remained infective for 212 days. Moisture levels within both clayey and sandy soils did not appreciably affect recovery of larvae. Active nematodes recovered from soil are not necessarily infective. Temperatures of -12, 0 and 4 C had little adverse effect on lar...

ABSTRACT The stem nematode Ditylenchus dipsaci is of great economic importance worldwide as a parasite of agricultural crops and horticultural plants. The internal transcribed spacer (ITS) of rDNA from 23 populations of the D. dipsaci complex from various host plants were amplified and sequenced. Seven previously studied populations were also included in the study. The phylogenetic analysis of ...