A number of studies have reported the presence of dopamine in free-living and animal-parasitic nematodes (6), but, to our knowledge, Aphelenchus avenae is the only plant-parasitic nematode in which this neurotransmitter has been shown by direct assay of tissue homogenates (7). This paper presents experimental evidence of the existence of biochemical pathways leading to the production of dopamin...

cots in the family Commeliaceae. The basic morphology of these plants appears to favor root-knot nematode development in aboveground plant parts. Leaves of both plants develop in the crown near the soil; they are large, 20-30 cm long, and densely arranged so that nematodes on younger leaves are protected from direct solar irradiation. The dense pubescent foliage, especially the convoluted young...

Calorie values for a wide biological selection of nematodes, determined with a microbomb calorimeter, ranged from 3.86 to 6.85 Kcal/g. The mean of 5.095 Kcal from 16 species was lower than means recorded in three previous studies of other invertebrate groups. The nematode values were skewed to the lowest limit. Larvae of Ditylenchus dipsaci showed lower calorie values after storage, and the cal...