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Soybean cyst nematode (SCN, Heterodera glycines) has become the major yield-limiting biological factor in soybean production. Common bean is also a good host of SCN, and its production is challenged by this emerging pest in many regions such as the upper Midwest USA. The use of host genetic resistance has been the most effective and environmentally friendly method to manage SCN. The objectives of this study were to evaluate the SCN resistance in the USDA common bean core collection and conduct a genome-wide association study (GWAS) of single nucleotide polymorphism (SNP) markers with SCN resistance. A total of 315 accessions of the USDA common bean core collection were evaluated for resistance to SCN HG Type 0 (race 6). The common bean core set was genotyped with the BARCBean6K_3 Infinium BeadChips, consisting of 4,654 SNPs. Results showed that 15 accessions were resistant to SCN with a Female Index (FI) at 4.8 to 9.4, and 62 accessions were moderately resistant (10 < FI < 30) to HG Type 0. The association study showed that 11 SNP markers, located on chromosomes Pv04, 07, 09, and 11, were strongly associated with resistance to HG Type 0. GWAS was also conducted for resistance to HG Type 2.5.7 and HG Type 1.2.3.5.6.7 based on the public dataset (N = 276), consisting of a diverse set of common bean accessions genotyped with the BARCBean6K_3 chip. Six SNPs associated with HG Type 2.5.7 resistance on Pv 01, 02, 03, and 07, and 12 SNPs with HG Type 1.2.3.5.6.7 resistance on Pv 01, 03, 06, 07, 09, 10, and 11 were detected. The accuracy of genomic prediction (GP) was 0.36 to 0.49 for resistance to the three SCN HG types, indicating that genomic selection (GS) of SCN resistance is feasible. This study provides basic information for developing SCN-resistant common bean cultivars, using the USDA core germ plasm accessions. The SNP markers can be used in molecular breeding in common beans through marker-assisted selection (MAS) and GS.

The local temporal coherence is considered as another means of comparing two waveforms in order to provide a quantitative measure of the change in shape of a signal compared to a reference as a function of time from transit. It is shown that the local temporal coherence is effective in discriminating structural damage from both temperature changes and modest changes in surface conditions and these results are compared to those obtained from time domain and spectrogram differencing.

SBreeding effort to improve yield and other quantitative traits in common bean (Phaseolus vulgaris L.) has proven to be difficult. The use of molecular markers will improve our understanding of the genetic factors conditioning these traits and is expected to assist in the selection of superior genotypes. This study was conducted to identify genetic loci associated with 14 quantitative traits responsible for seed yield, yield components, and plant architecture traits in common bean. A population of 142 [F.sub.2:4] lines that was developed from a cross between OAC Seaforth and OAC 95-4, was evaluated at two locations in Canada in 1998. The lines were assayed for random amplified polymorphic DNA (RAPD), restriction fragment length polymorphism (RFLP), simple sequence repeat (SSR), and amplified fragment length polymorphism (AFLP) markers. One hundred fourteen markers were assigned to 12 linkage groups. Growth habit and resistance to common bacterial blight [CBB, caused by Xanthomonas axonopodis pv. phaseoli (Smith) Vauterin, Hoste, Kosters & Swings = syn. X. campestris pv. phaseoli (Smith) Dyel were each mapped as single major genes on linkage groups G11 and G5, respectively. An alignment of the current map with the previous linkage map developed at the University of Florida and the core linkage map of bean was produced from 30 RFLP loci. Twenty quantitative trait loci (QTL) were identified for the 14 traits that were analyzed. The number of QTL identified per trait ranged from one to three. A multiple QTL model for each trait showed that these genomic regions accounted for 11.3 to 43.1% of the total phenotypic variation for the traits. Five of the twenty QTL were detected at both locations. The strengths of QTL effects for a given trait appeared to be slightly different among locations, but the positions of QTL on the map were stable across locations., SELECTION FOR YIELD and other inagronomic traits, including resistance to biotic and abiotic stresses, upright plant architecture, growth habit, lodging resistance, and maturity has been extensively utilized by bean breeders [...]