Soybean cyst nematode (Heterodera glycines, SCN) is the most harmful pathogen of soybean (Glycine max (L.) Merr.) worldwide. In 2016, a new soybean-parasitic nematode, Heterodera sojae (the white nematode) was found parasitizing roots plants in Korea. To investigate distribution and population density H. sojae, 943 soil samples were collected from fields all nine provinces Korea 2017 to 2018. C...

High-performance liquid chromatography and Sinorhizobium fredii USDA191 nodC-lacZ gene fusion were used to monitor changes in the isoflavonoid content of soybean roots infected with Heterodera glycines isolate TN1. Isoflavonoid concentrations in infected roots of both H. glycines-resistant Hartwig and susceptible Essex soybean were two to four-fold higher than those of uninfected roots 2 and 3 ...

Fructose-bisphosphate aldolase (EC 4.1.2.13) is a key enzyme in glycolysis. We have characterized full-length coding sequences for aldolase genes from the cyst nematodes Heterodera glycines and Globodera rostochiensis, the first for any plant-parasitic nematode. Nucleotide homology is high (83% identity), and the respective sequences encode 40 kDa proteins with 89% amino acid identity. Genomic ...

Thirty-five populations of Heterodera glycines and populations of 15 other Heterodera, Globodera, and Punctodera species were studied morphometrically and some were compared serologically. There was a wide range of each measurement within each nematode population. Except for one soybean cyst nematode population from Indiana, which was a tetraploid and considerably larger than the others, morpho...

Eighteen soybean fields, six each with race 3, race 4, or Bedford population of Heterodera glycines, were selected for testing of host variability. Each field was divided into three sections, and a bulk soil sample was taken from each section. The 54 bulk soil populations (BSP) and 270 single cyst populations (SCP) were subjected to race determination tests. Tests of the 18 BSP and 90 SCP from ...

Half-root tests were established to examine the association between Heterodera glycines and the blue strain of Fusarium solani, the causal agent of sudden death syndrome (SDS) of soybean. Two independent root systems were established for soybean 'Coker 156' and inoculated (half root/half root) with F. solani, H. glycines, both organisms on opposite root halves, both organisms on one root half, ...

One hundred thirty-eight isolates of Heterodera glycines from nine states in the United States, People's Republic of China, and Indonesia were tested on the four standard soybean race differentials. A total of 12 variants were found, including the five races described previously. The seven variants that did not correspond to one of the described races and reports from other areas of populations...

The pathogenicity of Heterodera glycines, Meloidogyne incognita, and Pratylenchus penetrans on H. glycines-resistant 'Bryan,' tolerant-susceptible 'G88-20092,' and intolerant-susceptible 'Tracy M' soybean cultivars was tested using plants grown in 800 cm(3) of soil in 15-cm-diam. clay pots in three greenhouse experiments. Plants were inoculated with 0, 1,000, 3,000, or 9,000 H. glycines race 3 ...

A 4-year systematic survey for the presence of soybean cyst nematode Heterodera glycines in Ohio soybean fields was initiated in 1992. A total of 667 soybean fields in 63 counties was sampled. Heterodera glycines was present in 91 fields in 40 counties based on soil samples collected, and in one field in each of three additional counties based on soil samples submitted to the Plant and Pest Dia...

Several abiotic and biotic stresses can affect soybean in a growing season. Heterodera glycines, soybean cyst nematode, reduces yield of soybean more than any other pathogen in the United States. Field and greenhouse studies were conducted to determine whether preemergence and postemergence herbicides modified the reproduction of H. glycines, and to determine the effects of possible interactive...