Marker-assisted backcrossing is a powerful method for developing new cultivars. To develop genomic-wide markers, genotyping-by-sequencing (GBS) can be an efficient method. However, unrefined low-quality markers and missing data between markers can contribute to hampering the marker selection process, particularly in multi-way crosses. In this study, we aimed to calculate the recovery rate of offspring individuals and minimize errors that occur among a large number of markers. Initially, missing data were imputed by comparing samples using the k-nearest neighbor (k-NN) algorithm. Thereafter, low-quality single-nucleotide polymorphisms (SNPs) were corrected by applying the graphical representation method based on the k-NN algorithm in order of the SNPs in a chromosome designed for a multi-parental population. Four-way cross and double-backcrossed tomato BC₁F₁ (230 lines) and BC₂F₁ (96 lines) populations were genotyped by GBS. The genotype of samples of the BC₁F₁ and BC₂F₁ populations was determined based on the parental haplotype. Thus, the method of visualizing the genotype of offspring individuals, generated via crosses of multiple parents, not only improves estimation of the recovery rate but also facilitates easier selection in breeding programs.

‘Anmi’ is a new BPH (Brown planthopper) resistant japonica rice cultivar possessing the Bph18 gene derived from wild rice, Oryza australiensis and high yield potential with good grain quality. ‘Anmi’ was derived from a cross ‘Junam’ and ‘IR65482-7-216-1-2’ by a molecular marker assisted backcross breeding. The introgression line ‘IR65482-7-216-1-2’, the source of the Bph18 gene, was used as the donor parent for BPH resistance and ‘Junam’, a BPH-susceptible elite japonica cultivar with good grain quality, was used as the recurrent parent. ‘Anmi’ was developed by three times backcross the F1 plants with ‘Junam’. The heading date of ‘Anmi’ is August 15 in central plain area, which is 5 days later than that of ‘Hwaseong’. It has 77 cm in culm length, 21 cm in panicle length. The number of spikelets per panicle is more than that of ‘Hwaseong’ and 1,000 grain-weight of brown rice is 22.1 g which is less than 22.7 g of ‘Hwaseong’. Milled rice kernel of ‘Anmi’ is clear in appearance, low in amylase content and excellent in palatability of cooked rice. ‘Anmi’ shows resistance to BPH, leaf blast disease, bacterial blight, rice stripe disease but susceptible to other virus disease and insect pest. The milled rice yield performance of ‘Anmi’ is about 5.76 MT/ha in local adaptability test for three years. This cultivar is adaptable to central plain area of Korea.