'Griffin' (Reg. No. CV-25, PI 672148), is a canola-quality, winter oilseed rape (Brassica napus L.) and is a dual-purpose forage and grain canola cultivar developed for Kansas, with potential to be grown across the southern Great Plains. It was tested as the experimental cultivar KS4022 and was released by K-State Research and Extension. The ability of Griffin to withstand the effects of simulated grazing and its excellent forage quality compared with 'Wichita' make it a good candidate for dualpurpose use. In simulated grazing studies, Griffin had winter survival superior to Wichita across all treatments; Griffin averaged 80.4% survival across grazing treatments, whereas Wichita averaged 69.4%. At the optimum timing for forage harvest, Griffin's final grain yield was reduced by 36.6%, while Wichita's final grain yield was reduced by 61.1% compared with the no-forage harvest treatment. Griffin yields a high-protein, highly digestible, nutritious forage for livestock producers. Griffin also possesses beneficial morphological features that could be used in breeding of new cultivars. A prostrate growth habit and the ability to avoid fall stem elongation are important characteristics to consider when selecting a canola cultivar with optimum winter survival.

Cercospora sojina Hara, the causal agent of frogeye leaf spot of soybean (Glycine max (L.) Merr.), causes yield reductions worldwide. Although the phenotypic diversity (physiological races) of this pathogen has been assessed through its ability to affect soybean lines with different resistant genes (Rcs genes), little is known about the pathogen's genetic diversity. In order to better understand the genetic diversity that exists with C. sojina, a historical collection of 62 C. sojina isolates from Brazil (10 isolates), China (7 isolates), Nigeria (1 isolate), and United States (44 isolates) was used for genetic diversity analysis with amplified fragment length polymorphism (AFLP) markers. The average genetic similarity of the isolates was 0.56 on a scale between 0 and 1, indicating a high degree of genetic diversity within the species. Cluster analysis resulted in two major clusters and seven sub-clusters. Two isolates collected from Georgia were clustered together, and two isolates from China were clustered together. Besides these four isolates, no clear separation of isolates based on origin was found. Our results provide evidence that substantial genetic diversity exists within the species of C. sojina and that selection for broad-spectrum host-resistance should be targeted in soybean breeding programmes.

‘Riley’ (Reg. No. CV‐24, PI 663949), a canola‐quality winter oilseed rape (Brassica napus L.), was developed and released by the Kansas Agricultural Experiment Station. Riley is a selection from the cross with pedigree KS3580/‘Jetton.’ Riley was tested in regional yield trials as the experimental variety KS4158 and was an entry in the National Winter Canola Variety Trial from 2008 through 2010. Riley was released because of its disease tolerance, improved oil content, and superior yield compared with ‘Wichita’ and other check varieties. The fatty acid profile and glucosinolate content of the meal of Riley are excellent quality. Riley had significantly greater yield than all check cultivars (P < 0.05), yielding 113% of Wichita and 116% of ‘DKW46‐15’. Through 27 site‐years on the southern Great Plains and High Plains, Riley averaged 400 g kg−1 total oil compared with Wichita's average of 388 g kg−1 (P < 0.05). The performance record of Riley suggests an increase in yield and consistency among commercial cultivars. As winter canola is planted on more hectares, demand is growing for improved genotypes.

ABSTRACTSoybean [Glycine max (L.) Merr.] resistance to soybean rust (SBR) caused by Phakopsora pachyrhizi could reduce reliance on fungicides to manage this disease. The objective of this study was to identify soybean germplasm with resistance to field populations of P. pachyrhizi in the United States. Field evaluations of 576 accessions from the USDA Soybean Germplasm Collection for resistance to SBR were conducted at seven locations in the southern United States between 2006 and 2008. Accessions from maturity groups (MG) 000 to X and North American susceptible check cultivars from each MG except X were rated for disease severity in all year–location environments, and for disease incidence, fungal sporulation, lesion type, and/or uredinia density in certain environments. While none of the accessions was immune in all environments, 64 were resistant in two or more locations each year that they were tested. Some accessions appeared to be more resistant in certain environments than in others. Of the original four Rpp genes described in the literature, Rpp1 provided the highest level of resistance, and among the accessions with uncharacterized Rpp genes, PI 567104B had the highest overall resistance across environments. The plant introductions confirmed to be resistant in these evaluations should be useful sources of genes for resistance to North American populations of P. pachyrhizi

Frogeye leaf spot (FLS), caused by Cercospora sojina K. Hara, is a common disease of soybean [Glycine max (L.) Merr.] in most soybean-growing countries of the world. Significant yield losses of soybean (10-60%) have-been attributed to FLS under hot and humid growing conditions. The FLS in the southern United States has been kept under control by planting resistant cultivars. Cercospora sojina is a dynamic pathogen with extensive virulence or race diversity. The current number of C. sojina isolates at the University of Georgia collection is 93. Assigning race designations to this large number of isolates has been difficult because of the lack of a well-defined set of differentials. To facilitate future studies of the genetics of soybean resistance to FLS and the identification and comparison of existing and future races of C. sojina, we have reassessed both the soybean differentials and the C. sojina races. Based on the reactions of 93 isolates of C. sojina on 38 putative soybean differentials, we propose a core set of 12 differentials and 11 races that represent the major diversity among the 93 C. sojina isolates. The definition of these 12 differentials and 11 races should provide the foundation for the identification and comparison of additional soybean resistance genes and new races of C. sojina.

Frogeye leaf spot (FLS), caused by Cercospora sojina Hara, is a serious disease of soybean (Glycine max (L.) Merr.). Complete resistance to all isolates of FLS was reported in the cul- tivar Davis, and the Rcs3 gene was mapped on Linkage Group J (LGJ), near the simple sequence repeat (SSR) markers Satt244 (64.9 cM) and Satt547 (67.7 cM). The objectives of this study were to track the transmission of Rcs3 from Davis to its descendants and deter- mine the cosegregation of Rcs3 and Davis SSR marker bands. Reaction of 64 lines inoculated with 15 virulent isolates of C. sojina was used in conjunction with molecular data from four SSR markers spanning 6.2 cM surrounding the Satt244-Satt547 interval. In addition, 38 puta- tive soybean differentials were characterized for these markers and their reaction to 93 isolates of C. sojina to evaluate the uniqueness of the Rcs3 alleles. The results showed an association (Yules Y = 0.87, p < 0.001) between resistance to FLS and Satt244 and Satt547. However, unlike previously reported, the locus Satt244 is duplicated. Cosegregation of the 156/182-bp bands at Satt244 and 242-bp band at Satt547 in known Rcs3 lines suggests that the two mark- ers can be used in the selection for resistance to FLS if the pedigree traces to Davis or one of its Rcs3 descendants. It also suggests the pos- sibility of linkage disequilibrium in this segment of LGJ. Therefore, analyzing resistance to FLS with either one of the two SSR markers would be cost-effective in marker-assisted selection.

Introduction Canola is an agronomic crop grown in many countries for production of vegetable oil and meal. Demand for canola oil continues to increase worldwide. People consume canola oil and consider it to be a healthy oil with low levels of saturated fats. More recently, there also is intense interest in using canola oil to produce biodiesel to replace diesel fuel. Canola meal is normally fed to poultry and livestock as a source of protein.

Frogeye leaf spot (FLS), caused by Cercospora sojina Hara, has become a more frequent disease in soybean, Glycine max (L.) Merr., across the USA. The Rcs3 gene provides resistance to all known races of C. sojina To provide resources for efficient marker‐assisted selection (MAS) of Rcs3, we developed and evaluated several single nucleotide polymorphisms (SNP) and insertions or deletions (InDels) markers linked to Rcs3 We surveyed 13 bacterial artificial chromosome (BAC) end sequences that were anchored with simple sequence repeat (SSR) markers Satt244 and Satt547 along with the two SSRs containing clones in six soybean cultivars (Davis, Cook, and Young that have the Rcs3 allele and Blackhawk, Bragg, and Lee that have the rcs3 allele) for SNPs. A total of 19 SNPs/InDels were identified and validated, but only 11 mapped near Rcs3 in a F2 population of Davis × Blackhawk. The Rcs3 gene was positioned near Satt244 and 0.50 cM from SNPs AZ573TA150 and AZ573CA393. None of the SNPs or InDels identified appeared to contribute directly to the Rcs3 phenotype, but 11 mapped within a 3‐cM interval surrounding Rcs3 These 11 markers were further validated for association with Rcs3 and for their potential in MAS in 64 lines and cultivars. Our results suggest that the two markers AZ573TA150 and AZ573CA393 could be used in MAS for Rcs3. Allele specific oligonucleotide probes specific for MAS were developed for a direct hybridization assay on a Luminex 100 flow cytometry platform.

The crop-sequence and rotational effect of incorporating alternative crops of canola ( Brassica napus ) as a winter crop and pearl millet ( Pennisetum glaucum ) as a summer crop into a double-crop system of winter wheat ( Triticum aestivum ) and soybean ( Glycine max ) on crop pest incidence, stand, and grain yield was studied at Plains, GA. Twelve double-cropping sequences that substituted winter canola and pearl millet at various intervals in a wheat/soybean double-crop system were studied for five seasons. Previous crop sequence had little effect on stand and grain yield of winter canola but the incidence of Sclerotinia stem rot was greater when canola was grown continuously. Winter infestations of the Hessian fly, Mayetiola destructor (Say), in wheat were reduced following canola than wheat but tended to be greater following pearl millet than soybean. Stand of both pearl millet and soybean were reduced following canola as compared to wheat. Infestations of false chinch bugs ( Nysius raphanus Howard) were greater on seedling stands of both summer crops following canola. Stand losses in pearl millet were associated with false chinch bug infestations but stand losses in soybean most likely were due to several factors. Both crops compensated for stand differences so that grain yield was not affected by previous winter crop. Infection rate of soybean by soybean stem canker was not affected by previous crop sequence. In general pearl millet had little effect on pest incidence and agronomic performance of other crops studied. Stand reductions of summer crops probably can be mitigated so that the beneficial effects of canola in reducing insect and diseases in winter wheat can be realized in a wheat/soybean double-crop system.

Phakopsora pachyrhizi, the causal agent of Asian Soybean Rust (SBR) (Fig. 1), has been documented on many legume hosts (3,20,23,25,30). However, it is best known for its devastating effect on soybean yields in Asia and South America (2,6,13), and has received much media attention in the United States. In November 2004, the disease was first detected in the continental United States in a production soybean field on a research farm near Baton Rouge, Louisiana (6,26). In the following weeks, the disease was found in Alabama, Arkansas, Georgia, Florida, Mississippi, Missouri, South Carolina and Tennessee (6,22). At that time, many researchers felt that the disease could become widespread in the Southeast and Midwestern states in 2005. However, by year’s end, SBR was only observed in the Southeast. The disease did not spread to the Midwestern soybean producing states, perhaps due to low inoculum levels, low spore viability, and/or poor environmental conditions for SBR development. Dr. Layla E. Sconyers (Corresponding author: lsconyrs@uga.edu) Department of Plant Pathology University of Georgia Coastal Plain Experiment Station Tifton, GA 31793

Bud blight, caused by Tobacco ringspot virus (TRSV; Genus: Nepovirus; Family: Comoviridae), can significantly reduce the seed yield and seed quality of soybean [Glycine max (L.) Merr.]. The identification of resistance genes and the development of resistant cultivars constitute an effective strategy for preventing yield loss. The objectives of this study were to identify and map quantitative trait loci (QTLs) conditioning resistance to bud blight and validate their genomic location with two populations derived from the cross of ‘Young’ (resistant) × PI 416937 (susceptible). One population consisted of 116 F4:7 lines and was used to map restriction fragment length polymorphism (RFLP) markers associated with resistance to bud blight. The lines were grown in one‐row plots in a randomized complete block design with two replications. The plots were naturally infected with TRSV. At maturity, soybean plots were visually scored according to the number of plants that exhibited terminal bud death. A major QTL was identified and mapped on linkage group (LG) F by the RFLP marker K644_1. It accounted for 82% of the variation in bud blight score. To verify the genomic location of the major bud blight QTL, a second population of Young × PI 416937 that consisted of 180 F2:3 lines was evaluated. In this population, simple sequence repeat (SSR) markers on LG F near the putative genomic location of the bud blight QTL were utilized. The major QTL conditioning bud blight resistance was confirmed and found to be closely linked to the Satt510 marker.