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A large set of potential microsatellites markers covering the entire genome are required for genetic diversity, mapping and functional genomics studies. In this study, a total of 37,572 microsatellites with frequency of 83.25 microsatellites per Mb were mined in the recently sequenced Fagopyrum tataricum. Among these 37,572 microsatellites, most of the microsatellites were di-nucleotide (26,196, 69.72%) and AT/TA repeat motifs were the most abundant (24,742, 65.85%). A total of 26,549 microsatellite markers were designed from the flanking sequences of 37,572 microsatellites and 2643 (9.96%) were genic microsatellite markers. All of these newly-developed microsatellite markers were physically anchored to the eight chromosomes of F. tataricum and the first and high-density physical map was constructed with an average marker density of 58.82 markers per Mb. Amplification efficiency and experimental evaluation of the newly-developed microsatellite markers assessed with 440 markers randomly selected in F. tataricum, showed that these microsatellite markers are highly effective and valuable. The large number of new microsatellite markers and their location on the physical map provided a valuable resource for studying diversity, constructing genetic maps, functional gene mapping, QTL exploration and molecular breeding in Fagopyrum species. [ABSTRACT FROM AUTHOR]

Nitrogen fertilizer and planting density are two crucial factors that affect the yield of common buckwheat ( Fagopyrum esculentum M.). Youqiao2, a common buckwheat cultivar with high photosynthetic capacity and planted widely in local production was used to investigate the effects of nitrogen fertilizer and planting density on the leaf photosynthetic characteristics, agronomic traits, and grain yield in common buckwheat by a split plot design. The main plots were assigned to three nitrogen fertilizer rates: 0, 45, and 90 kg ha −1 , and the subplots were assigned to three planting densities: 60, 90, and 120 plants m −2 . Results showed that the grain yield was significantly and positively correlated with net photosynthesis rate (P n ), stomatal conductance (G s ), transpiration rate (T r ), stomatal limitation value (L s ), chlorophyll content (SPAD value), leaf area index (LAI), plant height, stem diameter, branch number, internode number, grain number per plant, and 1000-grain weight, while significantly and negatively correlated with intercellular CO 2 concentration (C i ) and water-use efficiency (WUE). The P n , G s , T r , L s , SPAD, LAI, grain yield, stem diameter, branch number, internode number, grain number per plant, and 1000-grain weight increased and then decreased with the increase of nitrogen fertilizer and planting density, and their maximum values appeared in the nitrogen fertilization of 45 kg ha −1 and planting density of 90 plants m −2 treatment. The C i and WUE decreased and then increased with the increase of nitrogen fertilizer and planting density, and their minimum values appeared in the nitrogen fertilization of 45 kg ha −1 and planting density of 90 plants m −2 treatment. The plant height increased with the increase of nitrogen fertilizer, while decreased with the increase of planting density. These results suggested that nitrogen fertilizer and planting density had significant effects on the leaf photosynthetic capacity, agronomic traits, and grain yield of common buckwheat, and the combination of nitrogen fertilization of 45 kg ha −1 and planting density of 90 plants m −2 is recommended for common buckwheat planting. [ABSTRACT FROM AUTHOR]