This manuscript reports on the application of microsatellite markers to assess the effectiveness of controlled crosses and assess the genetic identity of seed samples from a same common bean cultivar (BRS Estilo

The main goal of this work was to select resistance sources to common bean anthracnose by field phenotyping and DNA marker-assisted screening. Fifty-five common bean genotypes, including differential varieties, characterized resistance sources, elite lines, cultivars and controls, were evaluated in a field inoculation trial and screened with SCAR markers linked to resistance genes that are important in Brazil. The field trial was carried out in Santo Antônio de Goiás, GO, Brazil, during the fall/winter growing season of 2014, using artificial inoculation with a mixture of six races of Colletotrichum lindemuthianum, selected based on their high virulence and prevalence in Brazil. Amplification reactions with the SCAR markers previously identified as linked to important anthracnose resistance genes on Brazil followed standard procedures. Twenty-eight of the 58 genotypes were resistant to anthracnose (mean severity score ≤ 3.5). Ten of these 28 resistant genotypes stood out because they presented a mean anthracnose severity score of 1.0. Four of the six SCAR markers tested shown to be useful for the assisted selection of their respective target genes (SH18 and SAS13 for Co-4 2 , SAB03 for Co-5, and SAZ20 for Co-6). Two carioca seeded elite lines were highlighted by the phenotypic and molecular ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 17 (3): gmr18066 A.F. Vieira et al 2 screening: K10 (Co-3 4 , Co-4 2 , Co-5 and Co-6) and K13 (Co-4²). The phenotypic and molecular characterization of candidate resistance sources to common bean anthracnose based on their disease reaction in field inoculation trials and on the analysis with molecular markers linked to resistance genes has shown to be a useful strategy. These results aid in the selection of donor parents and resistant lines to be preferably explored by common bean breeding programs in Brazil.

This work aimed to evaluate the drought tolerance of transformed plants of the cultivar BRSMG Curinga that overexpress the rice phospholipase D α1 (OsPLDα1) gene. The productivity of independent transformation event plants of the OsPLDα1 gene was evaluated in an experiment where 19 days of water deficit were applied at the reproductive stage, a very strict growing condition for upland rice. The non-genetically modified cultivar (NGM) under drought treatment reduced productivity by 89% compared with that under irrigated treatment, whereas transformed plants (PLDα1_E2) reduced productivity by only 41%. After the drought treatment, the PLDα1_E2 plants productivity was five times greater than that of the NGM plant. Moreover, no adverse effects on growth and development of the transgenic plants were observed. Seven days after the resumption of irrigation, PLDα1_E2 plants had higher stomatal conductance, greater photosynthetic rate, and transpiration rate than did NGM plants, as well as a higher expression level of the OsPLDα1 gene. A delay in the senescence process was observed in these PLDα1_E2 plants, and this was determined for the recovery of photosynthesis, with greater expression of the Rubisco and lower expression of the SOD. This finding was suggestive of decreased oxidative stress, probably due to gas exchange by the partial closure of the stomata of these transformed plants, which prevented the formation of reactive oxygen species. OsPLDα1 gene overexpression resulted in a reduction in production loss under severe water deficit and revealed a possibility for the development of upland rice cultivars that are more tolerant to extreme drought conditions.

The objective of this work was to identify and validate single-nucleotide polymorphism (SNP) markers related to grain yield in rice (Oryza sativa) core collection. The genome-wide association studies (GWAS) methodology was applied for genotyping of 541 rice accessions by 167,470 SNPs. The grain yield of these accessions was estimated through the joint analysis of nine field experiments carried out in six Brazilian states. Fifteen SNPs were significantly associated with grain yield, and out of the ten SNPs converted to TaqMan assays, four discriminated the most productive accessions. These markers were used for the screening of rice accessions with favorable alleles. The selected accessions were, then, evaluated in field experiments in target environments, in order to select the most productive ones. This screening reduces the number of accessions evaluated experimentally, making it possible to prioritize those with higher productive potential, which allows of the increase of the number of replicates and, consequently, of the experimental accuracy.

Breeding for water-deficit tolerance is fundamental to guarantee the sustainability of upland rice production, mainly due to the possibility of an increased frequency of drought episodes due to climate change. This work aimed to identify single nucleotide polymorphism (SNP) markers, derived from RNA sequencing (RNA-Seq), genome-wide association study (GWAS) and candidate genes from Arabidopsis, with potential for use in marker-assisted selection (MAS) for drought tolerance. RNA-Seq and GWAS were efficient in identifying useful SNP markers from the data obtained from three years of field experiments for 175 upland rice accessions, which were sequenced using 32 genes by Capture-Seq. Three genes were equally able to generate SNP markers that discriminated 95% of the 20 most drought susceptible accessions in the joint analysis of the experiments. The elimination of the genotypes with the unfavourable SNP allele reduced the initial number of accessions to one third, and transferring this result in a breeding routine, would enable to conduct smaller experiments per target location, increasing the precision and reducing the cost of the drought phenotyping.

Breeding for water-deficit tolerance is fundamental to guarantee the sustainability of upland rice production, mainly due to the possibility of an increased frequency of drought episodes due to climate change. This work aimed to identify single nucleotide polymorphism (SNP) markers, derived from RNA sequencing (RNA-Seq), genome-wide association study (GWAS) and candidate genes from Arabidopsis, with potential for use in marker-assisted selection (MAS) for drought tolerance. RNA-Seq and GWAS were efficient in identifying useful SNP markers from the data obtained from three years of field experiments for 175 upland rice accessions, which were sequenced using 32 genes by Capture-Seq. Three genes were equally able to generate SNP markers that discriminated 95% of the 20 most drought susceptible accessions in the joint analysis of the experiments. The elimination of the genotypes with the unfavourable SNP allele reduced the initial number of accessions to one third, and transferring this result in a breeding routine, would enable to conduct smaller experiments per target location, increasing the precision and reducing the cost of the drought phenotyping.

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