2012 Dryland Field Day Abstracts - Dept. of Crop and Soil Sciences ...

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2012 Field Day Abstracts: Highlights of Research Progress
cultivars and a mapping population has been developed. The mechanism of resistance to P. thornei and P. neglectus is poorly
understood; understanding how resistance works can increase the efficiency of resistance breeding. Early observational studies
show that, Louise a susceptible PNW-adapted spring wheat cultivar is readily penetrated by RLN but that AUS28451 has little to no
root penetration (Fig. 1). AUS28451 has increased amounts of lignin, a cell wall fortifying compound, and this trait is being
examined as a potential cause for the nematodes inability to penetrate the roots. Lignin stained root cross sections of Louise and
AUS28451 show more intense staining (red) in AUS28451 than Louise, particularly in the epidermal cell layers (Fig. 2). Lignin
extractions using a thioglycolic acid (TGA) precipitation method have also shown that AUS28451 has more root lignin than Louise
(Fig. 3). This data indicates that lignin amounts might be associated with for P. thornei and P. neglectus resistance. We are
continuing to investigate this association in a recombinant inbred mapping population derived from Louise and AUS28451.
Louise x x
Fig. 1.
Fig. 3.
Louise x
Managing Risks of Virus Infections in Pulse Crops in the Palouse Region
Sanford D. Eigenbrode 1 , Diana Roberts 2 , Ed Bechinski 1 , Damon Husebye 1 , Alexander Karasev 1 , Kevin McPhee 3 , and Bradley
Stokes 1 ; 1 Division of Entomology, U of I, Moscow; 2 WSU Extension, Spokane; 3 North Dakota State University
Fig. 2.
The Palouse region of eastern Washington and north Idaho is prime country for dry pea and lentil production. Annual infestations
of pea aphid (Acyrthosiphon pisum) and some of the viruses they carry, Pea enation mosaic virus (PEMV) and Bean leaf roll virus
(BLRV) vary from year to year. Heavy aphid infestations may cause heavy crop loss, especially when one or both viruses reach
epidemic proportions.
Some farmers apply insecticides routinely to avoid crop damage, while others defer treatment until aphid numbers warrant the
cost of treatment. Both approaches require an uncertain decision, and may result in unnecessary treatment costs or economic
yield loss. This project provides several tools that improve the management options available to producers.
1) Early Warning System: Since 2007 a geo-referenced network of 30 pan trap locations has been used to monitor aphid arrival.
PCR (polymerase chain reaction) is used to test the aphids from these sites to determine if they carry PEMV/BLRVF. These sites are
also surveyed twice per season for the presence of PEMV/BLRV in the pulse crop itself. The data are integrated into Geographic
Information System (GIS) data layers and made available online. Also, virologists at the University of Idaho are identifying
x