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Anthocyanins have significant functions in stress tolerance in pepper (Capsicum annuum L.) and also benefit human health. Nevertheless, the key structural genes and regulatory genes involved in anthocyanin accumulation in pepper fruits are still not well understood and fine mapped. For the present study, 383 F2 plants from a cross between the green-fruited C. annuum line Z5 and the purple-fruited line Z6 was developed. Two separate bulked DNA pools were constructed with DNAs extracted from either 37 plants with high anthocyanin content or from 18 plants with no anthocyanin. A combination of specific-locus amplified fragment sequencing (SLAF-seq) and bulked segregant analysis (BSA) was used to identify candidates for regions associated with anthocyanin accumulation. We identified a total of 127,004 high-quality single nucleotide polymorphism (SNP) markers, and detected 1674 high-quality SNP markers associated with anthocyanin accumulation. Three candidate anthocyanin-associated regions including the intervals from 12.48 to 20.00 Mb, from 54.67 to 56.59 Mb, and from 192.17 to 196.82 Mb were identified within a 14.10-Mb interval on chromosome 10 containing 126 candidate genes. Based on their annotations, we identified 12 candidate genes that are predicted to be associated with anthocyanin expression. The present results provide an efficient strategy for genetic mapping of and valuable insights into the genetic mechanisms of anthocyanin accumulation in pepper fruit, and allow us to clone and functionally analyze the genes that influence anthocyanin accumulation in this species. [ABSTRACT FROM AUTHOR]

First flower node (FFN) is an important trait for evaluating fruit earliness in pepper (Capsicum annuum L.), but the genetic mechanisms that control FFN are still poorly understood. In the present study, we developed 249 F2 plants derived from an intraspecific cross between the inbred pepper lines Z4 and Z5. Thirty plants with the highest FFN and 30 plants with the lowest FFN were chosen and their DNAs were pooled according to phenotype to construct two bulked DNA pools. Specific-locus amplified fragment sequencing (SLAF-seq) was combined with bulked segregant analysis (BSA) to identify candidate regions related to FFN. According to our genetic analysis, the FFN trait is quantitatively inherited. A total of 106,848 high-quality single nucleotide polymorphism (SNP) markers were obtained, and 393 high-quality SNP markers associated with FFN were detected. Ten candidate regions within an interval of 3.98 Mb on chromosome 12 harboring 23 candidate genes were identified as closely correlated with FFN. Five genes (CA12g15130, CA12g15160, CA12g15370, CA12g15360, and CA12g15390) are predicted based on their annotations to be associated with expression of the FFN trait. The present study demonstrates an efficient genetic mapping strategy and lays a good foundation for molecular marker-assisted breeding using SNP markers linked to FFN and for cloning and functional analysis of the key genes controlling FFN. [ABSTRACT FROM AUTHOR]