Soybean cyst nematode (Heterodera glycines, SCN) is the most destructive pathogen of soybean around the world. Crop rotation and resistant cultivars are used to mitigate the damage of SCN, but these approaches are not completely successful because of the varied SCN populations. Thus, the limitations of these practices with soybean dictate investigation of other avenues of protection of soybean ...

Computational methods offer great hope but limited accuracy in the prediction of functional cis-regulatory elements; improvements are needed to enable synthetic promoter design. We applied an ensemble strategy for de novo soybean cyst nematode (SCN)-inducible motif discovery among promoters of 18 co-expressed soybean genes that were selected from six reported microarray studies involving a comp...

Mercedes Diaz Arias, graduate student, Seed Science Center and Plant Pathology, Iowa State University; Gregory L. Tylka, professor, Plant Pathology, Iowa State University; Alison Robertson, assistant professor, Plant Pathology, Iowa State University; Leonor Leandro, assistant professor, Plant Pathology, Iowa State University; Gary Munkvold, professor, Seed Science Center and Plant Pathology, Io...

The impact of naturally occurring arbuscular mycorrhizal fungi on soybean growth and their interaction with Heterodera glycines were evaluated in nematode-infested and uninfested fields in Kansas. Ten soybean cultivars from Maturity Groups III-V with differential susceptibility to H. glycines were treated with the fungicide benomyl to suppress colonization by naturally occurring mycorrhizal fun...

Soybean plant responses to Heterodera glycines (H. glycines) race 3 infection were compared between resistant (Peking, LiaoK89102 and Franklin) and susceptible cultivars (Liao dou 10 and Kaiyu 10) at 10, 17, 20, and 23 days after inoculation (DAI). After inoculation with H. glycines race 3, the isozymes of peroxidase, polyphenol oxidase, superoxide dismutase, and catalase from the soybean roots...

Heterodera glycines is a cyst nematode that causes significant lost soybean yield in the U.S. Recent studies observed the aphid Aphis glycines and H. glycines interacting via their shared host, soybean, Glycine max. A greenhouse experiment was conducted to discern the effect of A. glycines feeding on H. glycines reproduction. An H. glycines-susceptible cultivar, Kenwood 94, and a resistant cult...

Growing soybean cyst nematode (SCN, Heterodera glycines Ichinohe) resistant varieties in fields infested with SCN can improve yield, but the impact of SCN on seed quality of lines with modified seed composition is unknown. The objective of this study was to determine if SCN resistant or susceptible rootstock influenced the composition of seed of soybean lines developed for desirable elevated le...

The soybean cyst nematode (SCN; Heterodera glycines) induces the formation of a multinucleated feeding site, or syncytium, whose etiology includes massive gene expression changes. Nevertheless, the genetic networks underlying gene expression control in the syncytium are poorly understood. DNA methylation is a critical epigenetic mark that plays a key role in regulating gene expression. To deter...

A summer-planted crop of alyceelover significantly (P < 0.05) increased the soil abundance of Meloidogyne arenaria race 2 juveniles by 3.7-fold when measured in the following spring. Maize, sorghum, and soybean had no significant effects on residual nematode numbers over the same period. Summer plantings of aeschynomene, cotton, hairy indigo, tespedeza, millet, peanut, and sorghum-sudangrass we...

A genetic analysis of parasitic ability in the soybean cyst nematode Heterodera glycines was performed. To identify and characterize genes involved in parasitism, we developed three highly inbred H. glycines lines, OP20, OP25 and OP50, for use as parents for controlled crosses. Through these crosses, we have identified genes in the inbred parents that control reproduction of the nematode on hos...