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Agrobacterium -mediated transformation provides a powerful tool for plant biotechnology. Great efforts have been made to unravel the underlying mechanisms of T-DNA integration. Creeping bentgrass ( Agrostis palustris Huds.), an economically important turfgrass species, has been widely studied for genetic transformation. In order to characterize T-DNA integration in this species, we analyzed T-DNA junction sequences in transgenic bentgrass obtained by transformation with A. tumefaciens strain EHA101 carrying a pPZP201-derived plasmid. Using T-DNA specific primers, inverse polymerase chain reaction (IPCR) and standard PCR were performed to identify T-DNA/plant junctions and T-DNA/T-DNA junctions, respectively. Sequence comparisons revealed that T-DNA right border (RB) termini were more intact, represented by a smaller range of border deletions and no backbone integration, compared to T-DNA left border (LB) termini. Multiple T-DNA arrays inserted at a single chromosome locus were detected in various configurations. It was shown that the formation of the multiple T-DNA arrays was governed by illegitimate recombination (IR), with sequence microsimilarities over and/or close to the T-DNA breaking points. It was also demonstrated that the fusion of two T-DNA copies was frequently associated with the formation of filler DNA and significant T-DNA truncation. Compositional analysis over the bentgrass sequences revealed a similar A / T ( A + T ) content but a polarized distribution of A and T associated with LB flanking sequence tags (FSTs) and RB FSTs, which was further documented in Arabidopsis T-DNA FSTs. DNA folding analysis on T-DNA FSTs suggested that the T-DNA target region had a potential of forming secondary structures, which may designate an active region for T-DNA integration. The results presented in this study shed new light on microsimilarity-based illegitimate recombination and advance our understanding of T-DNA integration.

Resistance to imidazolinone (IMI) herbicides has been incorporated recently into domesticated sunflower through conventional breeding methods. However, there are concerns regarding gene flow of the IMI-resistance trait to wild species and possible accompanying ecological consequences. Hybrids of domesticated sunflower with both common sunflower and prairie sunflower were created, with and without the imazamox-resistance trait. The relative fitness of imazamox-resistant (IMI-R) hybrids was compared with their imazamox-susceptible (IMI-S) counterparts. Greenhouse experiments were conducted to study the growth of IMI-R and IMI-S common and prairie sunflower hybrids under noncompetitive conditions. The photosynthesis rate of IMI-S prairie sunflower was slightly higher than that of IMI-R plants. However, relative growth rate, net assimilation rate, leaf area, and total dry weight were similar in IMI-R and IMI-S common and prairie sunflower, whereas plant height of IMI-S hybrid was greater than that of...

Gene flow from imidazolinone (IMI)-resistant domestic sunflower to IMI-susceptible common sunflower and prairie sunflower was studied. Under greenhouse conditions, pollen from IMI-resistant domesticated sunflower was applied to flower heads of IMI-susceptible common and prairie sunflower. In addition, field studies were conducted in 2000 and 2001 near Manhattan, KS, to evaluate IMI-resistant gene flow from IMI-resistant domesticated sunflower to common and prairie sunflower under natural conditions. Common and prairie sunflower were planted in concentric circles at distances of 2.5, 5, 15, and 30 m around a densely planted IMI-resistant domesticated sunflower species. For both greenhouse and field studies, IMI-resistant gene flow was determined by treating the progeny of both wild species with 40 g ai ha−1of imazamox. Greenhouse crosses made by hand showed that 94% of common sunflower and 79% of prairie sunflower were resistant or moderately resistant. The resistant plants were allowed to grow in the greenhouse and were backcrossed with the corresponding susceptible wild parents. Progeny of the backcross showed a 1:1 ratio of resistant to susceptible plants. In the field, gene flow was detected up to 30 m from the pollen source for both species, and it decreased as distance from the pollen source increased. In 2000, 11 to 22% of the progeny were resistant at 2.5 m from the pollen source and 0.3 to 5% were resistant at 30 m. In 2001, the number of resistant progeny did not exceed 7 and 2% at 2.5 and 30 m from the pollen source, respectively. The results of this study showed that IMI-resistant domesticated sunflower outcrosses with common and prairie sunflower over distances typically encountered near production fields. Also, backcrosses of resistant hybrids with wild parents are successful, further increasing the potential for the spread of IMI-resistant feral sunflowers.

Leaf and stem resistance to gummy stem blight ( Didymella bryoniae (Auersw.) Rehm.) in five resistant by susceptible crosses of cucumber (Cucumis sativus L.) was investigated using generation means analysis. No single gene of major effect controls either leaf or stem resistance to gummy stem blight in these five crosses. The mean number of effective factors controlling leaf resistance in the cross 'Slice' x 'Wis. SMR 18' was estimated to be at least five. Estimates of broad- and narrow-sense heritabilities indicated that environmental effects were larger than genetic effects. In general, additive variance was the larger component of genetic variance. Epistasis was significant in most crosses, and dominance was present in several crosses. Additive gene effects contributed more to resistance than to susceptibility in contrast with dominance gene effects. Reciprocal differences for leaf rating were detected in the crosses M 17 x 'Wis. SMR 18' and 'Slice' x 'Wis. SMR 18'. Phenotypic correlations between leaf and stem ratings were moderate ( r = 0.52 to 0.72). Estimates of genetic gain for resistance to gummy stem blight ranged from low to moderate. Breeding methods that make best use of additive variance should be used because much of the variance for resistance is additive, and dominance effects, at least in these crosses, tended to contribute to susceptibility. 2 Professor; to whom reprint requests should be addressed. Gummy stem blight causes severe defoliation and stem necrosis in the late stages of cucumber production. It is the second most important cucumber (Cucumis sativus) disease in North Carolina (St. Amand and Wehner, 1991), and is a serious disease of greenhouse cucumbers in The Netherlands, where it causes fruit rot (Van Steekelenburg, 1982). Gummy stem blight of cucumber is caused by Didymella bryoniae (Auersw.) Rehm (synonyms: Mycosphae- rella citrullina (C. O. Sm.) Gross., and Mycosphaerella melonis (Pass.) Chiu and Walker) and its anamorph Phoma cucurbitacearum (Fr.:Fr.) Sacc. (Farr et al., 1989) (synonyms: Ascochyta cucumis Fautr. and Roum., and Phyllosticta cucurbitacearum Sacc.). Several cultigens (breeding lines, cultivars, and plant introduc- tions) resistant to gummy stem blight have been reported. Using field screening methods in Wisconsin, 'Homegreen #2' and PI 200818 were reported to be resistant (Wyszogrodzka et al., 1986). In The Netherlands, greenhouse screening methods were used to identify several plant introduction accessions as resistant, including PI 200818 (Van Der Meer et al., 1978). In North Carolina, PI 164433, 'Slice', PI 390264, M 17 and M 12 were reported resis- tant using field screening methods (Wehner and St. Amand, 1993). Wyszogrodzka et al. (1986) reported that the realized heritability for foliar resistance in one cycle of mass selection within 'Homegreen #2' was 0.14 to 0.35. However, a comprehensive assessment of the inheritance of resistance in cucumber has not been reported. Knowledge of the genetic basis and heritability of resis- tance to Didymella bryoniae is essential for efficient development of resistant cultivars. Thus, a study was designed to determine the types of gene action controlling foliar and stem resistance, estimate the genetic and environmental components of variance, estimate heritability and gain from selection, estimate the minimum number

We describe fibromyalgia and our treatment using the weakly uricosuric agent guaifenesin, and we critique the recent Oregon study of guaifenesin treatment for fibromyalgia. Guaifenesin has proven to be our most effective medication to date for the treatment of fibromyalgia. Salicylates from any source will block the benefit of guaifenesin at a renal tubular level as they do in gout. Salicylates, which all plants make, are readily absorbed through skin. Even small amounts in cosmetics and other topicals will negate or slow the effects of all uricosuric agents we have used. Many maps made during treatment of patients' palpable lesions illustrate their becoming static or worsening in previously improving patients who unwittingly began using such preparations. More than half of the usual skin preparations could block patient improvement. Many patients are carbohydrate intolerant and must also be treated through diet. Dietary corrections for hypoglycemia and avoidance of salicylates must be maintained...

The effects of leaf age, guttation, stomata and hydathode characteristics, and wounding on the symptom development of gummy stem blight [Didymella bryoniae (Auersw.) Rehm] of cucumber (Cucumis sativus L.) were studied to develop a useful germplasm screening method. Older cucumber leaves were more susceptible than younger leaves in field, greenhouse, and detached-leaf tests. Compared to seedlings with true leaves, seedlings at the cotyledon stage were less susceptible, had a smaller variance for ratings, and were more likely to escape infection. Stomata density and hydathode counts were not correlated with field ratings; but, stomata length on older leaves was highly correlated with susceptibility y. In greenhouse and field tests, susceptibility y increased as guttation increased and actively guttating plants were more susceptible than nonguttating plants. Phylloplane moisture and/or nutrition were more important in the infection process than was stomata] opening. Although important, guttation was not necessary for infection. Dawn inoculation of field or greenhouse tests increased leaf symptoms compared with dusk inoculation. The increase was likely due to the free water and nutrients provided by guttation. Genotype ranks and ratings for detached-leaf tests were not correlated with field results. A useful method, highly correlated (r = 0.82 to 0.96) with field ratings. for screening germplasm in the greenhouse was developed. Methods of artificial inoculation or greenhouse screening of cucumbers (Cucumis sativus) for resistance to gummy stem blight Didymella bryoniae have been reported in at least 15 articles since 1949. Only Wyszogrodzka et al. (1986) indicated that their test was correlated with field resistance. Their report did not specifically measure the correlation between field and greenhouse tests, but found that cultigens (breeding lines, cultivars, and plant introduction accessions) resistant in greenhouse tests were usually resistant in field tests. They stated that the variability in greenhouse tests was problematic, and that greenhouse tests failed to detect the intermediate levels of resistance they found in field tests. The greenhouse screening method reported by Wyszogrodzka et al. (1986) did not account for the effects of phylloplane nutrition on the infectivity of Didymella bryoniae. Hordijk and Goosen (1962), Svedelius and Unestam (1978), and Svedelius (1990) have demonstrated the importance of nutrition external to the leaf in causing infection by D. bryoniae on cucumber. Nutrition external to the leaf stimulates infection by facultative necrotrophs and in some cases is required for infection to occur (Blakeman, 1971). Svedelius (1990) referred to D. bryoniaeas a facultative necrotroph. Curren ( 1969) reported that, like most facultative necrotrophs, D. bryortiae produces host cell-degrading enzymes. Svedelius and Unestam (1978) and Svedelius (1990) showed that cucumber leaves were most susceptible to infection near hydathodes, which r publication 19 Sept. 1994. Accepted for publication 14 Feb. 1995. The ported herein was funded in part by the North Carolina Agricultural ervice and by a grant from the North Carolina Pickle Producers . Use of trade names in this publication does not imply endorsement by or the products named, nor criticism of similar ones not mentioned. We cknowledge the advice of E. Echandi and the technical assistance of n, Jr. The cost of publishing this paper was defrayed in part by the page charges. Under postal regulations, this paper therefore must be ked advertisement solely to indicate this fact. raduate research assistant. Present address: US DA–ARS, 2004 on Hall, Kansas State Univ., Manhattan KS 66506-5501, to whom reprint requests should be addressed. SOC. HORT. SCI. 120(4):673-680. 1995. exude carbohydrates, salts, and minerals (Ivanoff, 1963). Svedelius and Unestam (1978) speculated that guttation may provide D. bryoniae with increased infectivity. Yarwood (1952) found that infection of broad bean (Vicia faba L.) inoculated with Botrytis cinerea was positively correlated with the amount of guttation. The effects of leaf exudates on the field resistance of cucumbers to D. bryoniae has not been investigated. There are conflicting reports on the infectability of cucumber cotyledons and on the relative susceptibility of differently aged leaves. Chiu and Walker (1949), Van Der Meer et al. (1978), and Wyszogrodzka et al. (1986) found that cotyledons of cucumber at the seedling stage were resistant to D. bryoniae and that inoculation of cotyledons was unreliable. Lee et al. (1984), however, stated that cucumber cotyledons were regularly infected in their tests, but it is unclear whether the plants tested were at the cotyledon stage or were 1 month old. Van Steekelenburg (1985) concluded that wounding was essential for infection of older leaves but not for young leaves. However, that conclusion was based on tests in which old leaves were not inoculated in the same manner as young leaves. Also, in an earlier paper, Van Steekelenburg (198 1) showed that the relative susceptibility of old vs. young leaves depended on the cultigen used. Contrary to Van Steekelenburg’s work, Hordijk and Goosen (1962) found that old leaves were more susceptible to D. bryoniae, and Van Der Meer et al. (1978) showed that the meristem and primordial true leaves were less susceptible than the first true leaf. Also, Prasad and Norton (1967) stated that cucumber leaves become more susceptible to D. bryoniae with age. Detached-leaf tests that detect field resistance to plant pathogens in a number of crops have been developed (Deadman and Cooke, 1986; Randhawa and Civerolo, 1985; Tedford et al., 1990; Yarwood, 1946;). Detached-leaf tests have a number of advantages over other methods such as multi-race or multi-pathogen testing without complications from systemic acquired resistance, the ability to test and maintain susceptible plants (which is impor

The resistance of the entire cucumber (Cucumis sativus L.) germplasm collection within the U.S. National Plant Germplasm System and of many available cultigens (improved cultivars, breeding lines, land races, feral cucumbers, and plant introductions) to anthracnose [Colletotrichum orbiculare (Berk. and Mont.) Arx] was tested under field conditions in North Carolina and compared with known resistant cultigens. Mean anthracnose leaf ratings for environments ranged from 5.5 to 7.7. Data within an environment were standardized to a mean of 4.5 and a standard deviation of 1 to improve comparisons among cultigens by removing the main effect of environments. The most resistant 27 cultigens are all of U.S. origin and are improved cultivars or breeding lines. The most resistant cultigens, for which multiple environment data are available, were 'Dual', 'Regal', 'Slice', and Gy 3. The most susceptible cultigens, for which multiple environment data are available, were PI 390248, PI 251028, and PI 277741. Thirty-one cultigens were classified resistant, 100 moderately resistant, and 773 susceptible. No plant introductions were found to be more resistant than the most resistant named cultivars or breeding lines tested. Cultigens found to be resistant in other studies were generally moderately resistant or resistant in this study, except for PI 179676 and PI 183445, which were susceptible in this test

Wheat (Triticum aestivum L.) breeding programs are currently developing varieties that are free of amylose (waxy wheat), as well as genetically intermediate (partial waxy) types. Successful introduction of waxy wheat varieties into commerce is predicated on a rapid methodology at the commodity point of sale that can test for the waxy condition. Near-infrared (NIR) reflectance spectroscopy, one such technology, was applied to a diverse set of hard winter (hexaploid) wheat breeders' lines representing all eight genotypic combinations of alleles at the wx-A1, wx-B1, and wx-D1 loci. These loci encode granule-bound starch synthase, the enzyme responsible for amylose synthesis. Linear discriminant analysis of principal components scores 1-4 was successful in identifying the fully waxy samples at typically greater than 90% accuracy; however, accuracy was reduced for partial and wild-type genotypes. It is suggested that the spectral sensitivity to waxiness is due to (1) the lipid-amylose complex which diminishes with waxiness, (2) physical differences in endosperm that affect light scatter, or (3) changes in starch crystallinity.

In this study, we used a comparative genome scan to examine patterns of population differentiation with respect to host plant use in Hesperotettix viridis, a Nearctic oligophagous grasshopper locally specialized on various Asteraceae including Solidago, Gutierrezia, and Ericameria. We identified amplified fragment length polymorphism (AFLP) loci with significantly elevated F(ST) (outlier loci) in multiple different-host and same-host comparisons of populations while controlling for geographic distance. By comparing the number and identities of outlier loci in different-host vs. same-host comparisons, we found evidence of host plant-related divergent selection for some population comparisons (Solidago- vs. Gutierrezia-feeders), while other comparisons (Ericameria- vs. Gutierrezia-feeders) failed to demonstrate a strong role for host association in population differentiation. In comparisons of Solidago- vs. Gutierrezia-feeding populations, a relatively high number of outlier loci observed repeatedly in different-host comparisons (35% of all outliers and 2.7% of all 625 AFLP loci) indicated a significant role for host-related selection in contributing to overall genomic differentiation in this grasshopper. Mitochondrial DNA sequence data revealed a star-shaped phylogeny with no host- or geography-related structure, low nucleotide diversity, and high haplotype diversity, suggesting a recent population expansion. mtDNA data do not suggest a long period of isolation in separate glacial refugia but are instead more compatible with a single glacial refugium and more recent divergence in host use. Our study adds to research documenting heterogeneity in differentiation across the genome as a consequence of divergent natural selection, a phenomenon that may occur as part of the process of ecological speciation.

BACKGROUND:Fibromyalgia syndrome (FMS), a common, chronic, widespread musculoskeletal pain disorder found in 2% of the general population and with a preponderance of 85% in females, has both genetic and environmental contributions. Patients and their parents have high plasma levels of the chemokines MCP-1 and eotaxin, providing evidence for both a genetic and an immunological/inflammatory origin for the syndrome (Zhang et al., 2008, Exp. Biol. Med. 233: 1171-1180). METHODS AND FINDINGS:In a search for a candidate gene affecting inflammatory pathways, among five screened in our patient samples (100 probands with FMS and their parents), we found 10 rare and one common alleles for MEFV, a gene in which various compound heterozygous mutations lead to Familial Mediterranean Fever (FMF). A total of 2.63 megabases of genomic sequence of the MEFV gene were scanned by direct sequencing. The collection of rare missense mutations (all heterozygotes and tested in the aggregate) had a significant elevated frequency of transmission to affecteds (p = 0.0085, one-sided, exact binomial test). Our data provide evidence that rare missense variants of the MEFV gene are, collectively, associated with risk of FMS and are present in a subset of 15% of FMS patients. This subset had, on average, high levels of plasma IL-1beta (p = 0.019) compared to FMS patients without rare variants, unaffected family members with or without rare variants, and unrelated controls of unknown genotype. IL-1beta is a cytokine associated with the function of the MEFV gene and thought to be responsible for its symptoms of fever and muscle aches. CONCLUSIONS:Since misregulation of IL-1beta expression has been predicted for patients with mutations in the MEFV gene, we conclude that patients heterozygous for rare missense variants of this gene may be predisposed to FMS, possibly triggered by environmental factors.

With the advent of next generation sequencing (NGS) technologies, single nucleotide polymorphisms (SNPs) have become the major type of marker for genotyping in many crops. However, the availability of SNP markers for important traits of bread wheat ( Triticum aestivum L.) that can be effectively used in marker-assisted selection (MAS) is still limited and SNP assays for MAS are usually uniplex. A shift from uniplex to multiplex assays will allow the simultaneous analysis of multiple markers and increase MAS efficiency. We designed 33 locus-specific markers from SNP or indel-based marker sequences that linked to 20 different quantitative trait loci (QTL) or genes of agronomic importance in wheat and analyzed the amplicon sequences using an Ion Torrent Proton Sequencer and a custom allele detection pipeline to determine the genotypes of 24 selected germplasm accessions. Among the 33 markers, 27 were successfully multiplexed and 23 had 100% SNP call rates. Results from analysis of "kompetitive allele-specific PCR" (KASP) and sequence tagged site (STS) markers developed from the same loci fully verified the genotype calls of 23 markers. The NGS-based multiplexed assay developed in this study is suitable for rapid and high-throughput screening of SNPs and some indel-based markers in wheat.

Genetic linkage maps are fundamental for the localization of genes conferring tolerance to greenbug, Schizaphis graminum (Rondani), feeding damage in sorghum, Sorghum bicolor (L.) Moench. Thirteen linkage groups (LGs) containing 60 simple sequence repeat (SSR) loci were mapped by using a set of sorghum recombinant inbred lines (RILs) obtained from the cross ‘96-4121’ (greenbug-tolerant parent) × Redlan (greenbug-susceptible parent). The LG spanned a distance of 603.5 cM, with the number of loci per LG varying from 2 to 14. Seventeen additional SSR loci were unlinked at a log of odds value of 3.0. Based on chlorophyll loss occurring after greenbug feeding, visual damage ratings, and soil plant analysis development (SPAD), chlorophyll–loss indices were recorded for each RIL and for the parents used in the cross. Composite-interval mapping identified three quantitative trait loci (QTLs) associated with biotype I and five QTLs associated with biotype K. The amount of phenotypic variation explained by these QTLs ranged from 9 to 19.6%. The identification of QTLs that influence greenbug tolerance will not only facilitate the use of marker-assisted selection in sorghum breeding programs but also will provide a solid foundation for detailed characterization of individual loci implicated in greenbug tolerance in sorghum.

Gummy stem blight [Didymella bryoniae (Auersw.) Rehm] is the second most important pathogen of field-grown cucumbers (Cucumis sativus L.) in North Carolina and a severe problem for greenhouse-grown cucumbers worldwide. To determine whether resistance exists under North Carolina field conditions, 83 cultigens [cultivars, breeding lines, and plant introduction (PI) accessions] were evaluated in the field for 4 years for their resistance to a mixture of D. bryoniae isolates. Plants were inoculated at the vine tip-over stage and rated for foliar lesion size and number. Cultigens identified as resistant in Wisconsin and The Netherlands were not resistant in North Carolina. When averaged over years and locations, the most resistant C. sativus cultigens were PI 164433, `Slice', PI 390264, M 17, and M 12. Several accessions of related Cucumis species were highly resistant: PI 299568 (C. myriocarpus Naud.), PI 282450 (C. zeyheri Sond.), PI 299572 (C. myriocarpus), and PI 233646 (C. anguria L.). The most susceptible cultivars were `Colet', `Meresto', `Supergreen', `Dura', `Pioneer', `Marketmore 76', `Pickmore', and `Addis'. `Calypso' and `Dasher II', popular cultivars in North Carolina, were moderately susceptible.

The rapid development of next-generation sequencing platforms has enabled the use of sequencing for routine genotyping across a range of genetics studies and breeding applications. Genotyping-by-sequencing (GBS), a low-cost, reduced representation sequencing method, is becoming a common approach for whole-genome marker profiling in many species. With quickly developing sequencing technologies, adapting current GBS methodologies to new platforms will leverage these advancements for future studies. To test new semiconductor sequencing platforms for GBS, we genotyped a barley recombinant inbred line (RIL) population. Based on a previous GBS approach, we designed bar code and adapter sets for the Ion Torrent platforms. Four sets of 24-plex libraries were constructed consisting of 94 RILs and the two parents and sequenced on two Ion platforms. In parallel, a 96-plex library of the same RILs was sequenced on the Illumina HiSeq 2000. We applied two different computational pipelines to analyze sequencing data; the reference-independent TASSEL pipeline and a reference-based pipeline using SAMtools. Sequence contigs positioned on the integrated physical and genetic map were used for read mapping and variant calling. We found high agreement in genotype calls between the different platforms and high concordance between genetic and reference-based marker order. There was, however, paucity in the number of SNP that were jointly discovered by the different pipelines indicating a strong effect of alignment and filtering parameters on SNP discovery. We show the utility of the current barley genome assembly as a framework for developing very low-cost genetic maps, facilitating high resolution genetic mapping and negating the need for developing de novo genetic maps for future studies in barley. Through demonstration of GBS on semiconductor sequencing platforms, we conclude that the GBS approach is amenable to a range of platforms and can easily be modified as new sequencing technologies, analysis tools and genomic resources develop.

Fibromyalgia syndrome (FMS) is a chronic musculoskeletal pain disorder affecting 2% to 5% of the general population. Both genetic and environmental factors may be involved. To ascertain in an unbiased manner which genes play a role in the disorder, we performed complete exome sequencing on a subset of FMS patients. Out of 150 nuclear families (trios) DNA from 19 probands was subjected to complete exome sequencing. Since >80,000 SNPs were found per proband, the data were further filtered, including analysis of those with stop codons, a rare frequency (

Table 1. Horticultural performance of ‘M 17’ and five standard pickling cucumber cultivars in two seasons and 3 years of performance trials at Clinton, N.C. Fig. 1. Pedigree of NCSU ‘M 17’ as a selection from a family (CH18) in the NCSU germplasm collection. ‘M 17’ is a monoecious, pickling cucumber (Cucumis sativus L.) inbred with moderate resistance to gummy stem blight [Didymella bryoniae (Auersw.) Rehm] under North Carolina field conditions. In our research, ‘M 17’ was the most resistant cucumber having American pickling-type fruit (St. Amand and Wehner, 1995; Wehner and St. Amand, 1993). Its resistance was not as high as the slicing cucumbers ‘Slice’ or ‘Homegreen #2’, but was similar to that of ‘Poinsett 76’.

Gummy stem blight (Didymella bryoniae (Auersw.) Rehm) is one of the major cucumber diseases, causing the second highest loss of any disease in North Carolina. Published methods of screening for resistance to this fungus are poorly correlated with field resistance. The objective of this study was to develop seedling or detached-leaf screening methods that are correlated with field resistance. Seedling tests examined the effects of: seedling age (1, 2 or 3 true leaves), days in humidity chamber, inoculum concentration (1×105, 1×106 or 1×107 spores per ml), time of inoculation (am vs. pm), fungal isolates, and cultigens. Detached leaf tests examined the effects of leaf age (1st, 2nd or 3rd true leaf), inoculum concentration (1×104, 1×105 or 1×106 spores per ml), and light levels during incubation (dark vs. 12h light/12h dark). Correlations between seedling tests and field data were moderate to high (r = 0.5 to 0.7). However, the coefficients of variation were also high. Correlations between detached leaf tests and field data were very low or negative.