Ground and whole Ditylenchus dipsaci maintained on onion callus contain no culturable micro-organisms when tested with five check media. Healthy onion callus does not produce pectolytic enzymes. Pectolytic enzymes are present in infected callus. These enzymes are, however, associated with resident nematodes and not host tissues. These results suggest that D. dipsaci is the actual source of the ...

Ditylenchus dipsaci and Fusarium oxysporum f. sp. medicaginis synergistically affected the mortality and plant growth of Ranger alfalfa, a cultivar susceptible to stem nematode and Fusarium wilt. The nematode-fungus relationship had an additive effect on mortality and plant growth of Lahontan (nematode resistant and Fusarium wilt susceptible) and of Moapa 69 (nematode susceptible and Fusarium w...

Plant-parasitic nematodes were found in 4 of the 12 clades of phylum Nematoda. These nematodes in different clades may have originated independently from their free-living fungivorous ancestors. However, the exact evolutionary process of these parasites is unclear. Here, we sequenced the genome sequence of a migratory plant nematode, Ditylenchus destructor We performed comparative genomics amon...

Since sa infoin may be in t roduced into areas infested with the alfalfa s tem nema tode , we ini t ia ted a s tudy to de te rmine if Ditylenchus dipsaci (K~ihn) Fi l ipjev is pa thogen ic to sa infoin , and what effect t empe ra tu r e has on n e m a t o d e pa thogen ic i ty and rep roduc t ion . G e r m i n a t i n g seeds of sa infoin ( O n o b r y c h i s viciaeJolia Scop. 'Esk i ' and 'Vi...

Ditylenchus dipsaci-infected and noninfected alfalfa plants in a naturally infested field were studied from July 1980 to September 1982. Forty-one percent of the plants died during the study. Ninety-seven percent of the plants that died were infected with D. dipsaci. Sixty-nine percent of the observed mortality occurred during winter. Forage yield of infected plants was significantly lower than...

1 Situation hyperbolique en dimension finie Considérons un champ de vecteurs dans R n de classe C k au voisinage de 0, k ≥ 2 , tel que 0 soit point stationnaire dZ dt = F (Z), F (0) = 0 (1) et notons L = DF (0). On dit qu'on a une situation hyperbolique si l'axe des imaginaires està une distance positive du spectre de L. Plus précisément, soit σ le spectre de L, i.e. l'ensemble de ses valeurs p...

Hot-water dips with and without the additives abamectin and sodium hypochlorite were evaluated for control of Ditylenchus dipsaci infection of garlic seed cloves. All treatments were compared to hot water-formalin clove dip disinfection and to nontreated infected controls for garlic emergence, midseason infection, bulb damage, and yield at harvest in field plots in 12 experiments. Hot-water tre...