Nematode parasitism genes encode secreted effector proteins that play a role in host infection. A homologue of the expressed Hg4F01 gene of the root-parasitic soybean cyst nematode, Heterodera glycines, encoding an annexin-like effector, was isolated in the related Heterodera schachtii to facilitate use of Arabidopsis thaliana as a model host. Hs4F01 and its protein product were exclusively exp...

Twelve bisexual species of Heterodera reproduced by amphimixis and had the same number of n=9 (2n=18) chromosomes in maturing oocytes. H. schachtii had slightly larger chromosomes than all other species. Only sperm nuclei with n=9 chromosomes were observed inside maturing oocytes and no specialized sex chromosomes were detected in any case. A "supernumerary" chromosome was observed occasionally...

Soybean-cyst nematode (Heterodera glycines) was first reported from Japan in 1915. It has since been reported from Korea (1936), Manchuria (1938), the United States (USA) (1954), and Egypt (1968). It is of major concern to soybean producers only in Japan and the USA. Soybean was a major crop in the Orient by 1915 but it was grown very little elsewhere. Since that time its cultivation has spread...

Calonectria crotalariae enhanced root penetration of Lee 74 (susceptible) and Centennial (resistant) soybeans by juveniles of race 3 of Heterodera glycines. Numbers of cysts in and on the roots of Lee 74 increased during the first 30 days in the presence of the fungus. Percentage of root infection by the fungus increased at 40 days in Lee 74 in the presence of the nematode. Numbers of cysts in ...

A dynamic model of nematode populations under a crop rotation that includes both host and nonhost crops is developed and used to conceptualize the problem of economic control. The steady state of the dynamic system is used to devise an approximately optimal decision policy, which is then applied to cyst nematode (Heterodera schachtii) control in a rotation of sugarbeet with nonhost crops. Long-...

A commercial seed treatment containing Pseudomonas cepacia was applied to Glycine max cv. Williams 82 (susceptible to Heterodera glycines) and was compared to Fayette soybean (resistant to H. glycines) for control of H. glycines at two locations in Illinois. The soil at the first location was sandy in texture and the field was irrigated, whereas the soil at the second location was a silty clay ...

We developed a quick and reliable technique to distinguish live and immobile (presumed dead) Heterodera glycines second-stage juveniles (J2) following their treatment with microbial culture filtrates. About 50 J2 in 1 ml of culture filtrate or water were placed in wells of a 24-well tissue-culture plate. After incubation, the nematodes in the wells were observed with the aid of an inverted micr...

AAC Richard is a food grade soybean [Glycine max (L.) Merr] cultivar with yellow hilum, high protein concentration, and good processing quality for foreign domestic soymilk, tofu, miso markets. It has resistance to SCN (soybean cyst nematode) (Heterodera Glycines Ichinohe). was developed at the Agriculture Agri-Food Canada (AAFC) Harrow Research Development Centre (Harrow-RDC), Harrow, Ontario ...

A new record species Heterodera ripae was found in the rhizosphere soil of nettle (Urtica sp.) on the bank of the Mangniu River in Shenyang City, Liaoning Province, China. The new record species can be characterized by vulval cone bifenestrate with circular or subcircular semifenestrae, vulval slit length averaging 34.2 μm, vulval bridge mostly broad, underbridge weak, bullae absent; the second...