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 ...

Yield of the soybean (Glycine max) cultivar Hartwig with resistance to all races of Heterodera glycines was compared to that of the susceptible cultivar, Deltapine 105, in a field infested with race 2 of this pathogen. The field had previously been in a cropping sequence experiment that provided a range of H. glycines population densities affording the opportunity to evaluate yield potential of...

A simple, rapid, and inexpensive method for evaluation of host-parasite interactions, based on monoxenic cultures, is described. Axenic root explants of Glycine max (L.) Merr., cultured on a holidic agar medium, were inoculated with axenic second-stage larvae of Heterodera glycines Ichinohe, Race 3. A clear separation of susceptible and resistant cultivars, based on numbers of mature female nem...

Heterodera glycines, the soybean cyst nematode, is a major yield-limiting pathogen in most soybean production areas worldwide. Field populations of H. glycines exhibit diversity in their ability to develop on resistant soybean cultivars. Since 1970, this diversity has been characterized by a bioassay used to assign a race classification to a population. The value of the race scheme is reflected...

A method is presented for in-situ hybridization to mRNA in second-stage juveniles (J2) of the soybean cyst nematode Heterodera glycines. The protocol was developed using a digoxigenin-labeled RNA probe transcribed from cDNA of a cellulase gene that was known to be expressed in the subventral esophageal glands of H. glycines. Formaldehyde-fixed J2 were cut into sections with a vibrating razor bl...

The corn cyst nematode Heterodera zeae [1], was first detected on the roots of maize collected from Rajasthan, India [1-3]. The pest has subsequently been reported to be present in Pakistan [35], Thailand [2,6], Egypt [7], Greece [8]. Portugal [9] and Virginia and Maryland in the USA [2,10,11] Heterodera zeae is restricted to warmer tropical and sub-tropical areas. And its distribution can be s...

Soybean cyst nematode (SCN) is the most destructive soybean pest worldwide. Host plant resistance is the most environmentally friendly and cost-effective way of mitigating SCN damage to soybeans. However, overuse of the resistant soybean [Glycine max (L.) Merr.] cultivars from limited genetic resources has resulted in SCN race shifts in many soybean-growing areas. Thus, exploration of novel sou...

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Several weeds serve as alternative soybean cyst nematode (SCN) hosts. Still, the relative reproductive capacity of SCN HG types (Heterodera glycines type) on weed hosts to is not well understood. This study examined reproduction three South Dakota endemic populations—PSCN-1 (HG 0), PSCN-2 2.5.7), and PSCN-3 7)—on purple deadnettle, field pennycress, henbit. The Relative Female Index (RFI) was c...