In a petri-dish study, development of the nematode Pratylenchus neglectus was observed every 4 days, and stage-specific development times were estimated, using a parameter estimation algorithm for a distributed-delay population model. The lower threshold temperature for development of a population of P. neglectus was 7.75 C. Temperatures above 25 C were unfavorable for this population on barley...

The reproduction and pathology of Pratylenchus penetrans has been observed on five cultivars of lettuce (Lactuca sativa var. scarola) : Parella, Lattughino biondo Lollo, S. Anna, Regina dei Ghiacci and Aurelia a t different soil temperatures and light exposure periods in climate-controlled units. The maximum population increase occurred a t 21-220 and a t 14 hourlday in Parella and S. Anna vari...

Greenhouse and growth chamber studies were made to investigate the downward systemic nematicidal activity of carbofuran and its analog 2,3-dihydro-2,2-dimethyl-7-benzofuranyl [(di-n-butyl)-4-aminosulfenyl] carbamate against Meloidogyne incognita, Tylenchorhynchus claytoni, and Pratylenchus penetrans. Oxamyl was used as standard in tests with T. claytoni. Both carbofuran and its analog reduced a...

Studies were conducted to investigate the basipetal translocation of nematicidal activity from foliar treatments of carbofuran and its analog, 2,3-dihydro-2,2-dimethyl-7-benzofuranyl ([dibutylamino]thio)methyl carbamate, on corn in microplot studies and on tobacco and potato in field trials. Two and three foliar applications of either product at 2,400 mug/ml (9-20 Kg ai/Ha) significantly reduce...

The feeding behaviour of Pratylenchus penetrans on root hairs was observed using video-enhanced contrast microscopy. The behayiouk could be separated into phases of probing, ce11 penetration by the stylet, salivation and food ingestion for brief and extended ,periods. &ter cell penetration, a small “ salivation zone ” was formed around the stylet tip. No feeding tubes were observed. The root ha...

In 1984-85 metham-sodium and the combination of 1,3-dichloropropene plus aldicarb decreased (P = 0.05) soil population densities of Pratylenchus penetrans at planting, midseason, and at harvest relative to the untreated control. These treatments increased (P = 0.05) marketable potato tuber yield from 27% to 46% in 1984 and from 23% to 37% in 1985, as compared with the control. In 1984 oxamyl (1...

Reproduction of Pratylenchus thornei on carrot disk cultures at different time periods after inoculation, temperature, and initial inoculum density was studied. At 25 C and with an initial inoculum of 25 females per disk, the final nematode population increased with increasing time after inoculation, although the populations after 25 and 50 days were not different. Nematode numbers increased by...