Pepper (Capsicum spp.) is one of the most important crops worldwide. The fruits of Capsicum species are known to contain high amounts of vitamins and carotenoids, and they have health-promoting properties. In this study, a total of 513 pepper accessions belonging to two Capsicum species, C. annuum and C. frutescens, were investigated for their morphological characteristics and contents of phytochemicals including carotenoids, β-carotene, vitamin C, capsaicinoids, and total soluble solids. The results revealed wide variations in morphological traits and phytochemical contents between the accessions and across species. In addition, the association of fruit color and orientation with phytochemical contents was evaluated; the results indicated that germplasm with yellow-colored and pendant-oriented fruits could be important due to their high vitamin C levels. Multivariate analysis of the agro-morphological and phytochemical parameters revealed that Capsicum germplasm were clearly distinguished according to species. Furthermore, cluster analysis showed that germplasms belonged to three groups, and six genotypes were determined as being good genetic resources with high health-promoting phytochemical contents. Especially, vitamin C content was positively correlated with fruit diameter, weight, and wall thickness. Our findings revealed morphological and phytochemical characteristics potentially useful for breeding programs.

The phenolic compounds in eggplant offer potential natural antioxidants for improved health. A large number of samples were examined in order to find eggplant germplasm with a high potential for health promotion. A genome-wide association study (GWAS) was conducted to identify single nucleotide polymorphisms (SNPs) associated with variations in total phenolic content (TPC) and antioxidant activity in eggplants, including ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) scavenging activity and ferric reducing antioxidant power (FRAP). TPC values varied from 14.19 to 842.90 mg gallic acid equivalent (GAE)/100 g of dry weight of eggplant fruit powder. TPC showed a strong positive correlation with both FRAP and ABTS (r = 0.89 *** and 0.77 ***, respectively). The GWAS identified 20 SNPs that were significantly associated out of 29,183 SNPs. Out of the 20 significant SNPs, 11 showed associations with TPC, 4 with ABTS activity, and 5 with FRAP. Among the SNPs associated with TPC, one SNP was found on each of Chromosomes 3, 4, 7, and 12. In contrast, Chromosome 5 comprised two SNPs associated to TPC. Furthermore, the gene encoding IRX12 laccase-4 on Chromosome 10 was found to contain five SNPs associated with TPC. Four significantly linked SNPs on Chromosomes 1 (1 SNP), 4 (2 SNPs), and 10 (1 SNP) were found to be related to ABTS activity. The identified SNPs will be further examined as markers for selecting desirable eggplant varieties and exploring the links between candidate genes, phenolic content, and antioxidant activity. The findings of this study could assist in further study and the development of eggplants with improved health advantages through targeted breeding.

Eggplant is one of the most economically and nutritionally important vegetables worldwide. The study of the association of phenotypic traits with genetic factors is vital for the rapid and efficient identification and selection of eggplant genetic resources for breeding purposes with desired traits. The eggplant resources (587) collected from different countries, including Korea, were used for establishing the core collection. A total of 288 accessions were selected from 587 Solanum accessions based on 52 single nucleotide polymorphisms (SNPs) markers together with 17 morphological traits. This core collection was further used to analyze the genetic associations of eggplant morphological variations. A large variation was found among the evaluated eggplant accessions for some agro-morphological traits. Stem prickles and leaf prickles showed a significant positive correlation (r = 0.83***), followed by days to flowering and days to maturity (r = 0.64***). A total of 114,981 SNPs were filtered and used for phylogenetic tree analysis, population structure analysis, and genome-wide association study (GWAS). Among the agro-morphological traits, significantly associated SNPs were found for six traits. A total of 377 significantly associated SNPs with six agro-morphological traits were identified. These six traits and the number of SNPs were: days to maturity (51), flower size (121), fruit width (20), harvest fruit color (42), leaf prickles (38), and stem prickles (105). The largest fraction of significant SNPs (11.94%) was obtained on chromosome Ch01, followed by Ch07 and Ch06 with 11.67% and 10.08%, respectively. This study will help to develop markers linked to the most important agro-morphological traits of eggplant genetic resources and support the selection of desirable traits for eggplant breeding programs.

On-Sook Hur, Hae-Ryun Kwak, Na-Young Ro, Yumi Choi, Sukyeong Lee, Aejin Hwang, Bichsaem Kim, Seong-Hoon Kim, and Bum-Soo Hahn. Korean J. Breed. Sci. 2022;54:1-7. https://doi.org/10.9787/KJBS.2022.54.1.1

Radish Cultivars Tania Afroz, Onsook Hur, Nayoung Ro, Jae-eun Lee, Aejin Hwang, Bichsaem Kim, Awraris Derbie Assefa, Ju Hee Rhee, Jung Sook Sung, Ho-sun Lee* and Bum-Soo Hahn* National Agrobiodiversity Center, National Institute of Agricultural Sciences, Rural Development Administration, Jeonju 54874, Korea National Institute of Crop Science, Rural Development Administration, Miryang 50424, Korea 3 International Technology Cooperation Center, Rural Development Administration, Jeonju 54875, Korea

Fusarium wilt is a serious disease that causes damping-off, serious wilt symptoms, or death in melon. The aim of this study was to evaluate the resistance of melon germplasm to Fusarium wilt and select promising disease-resistant accessions for further applications. Resistance to Fusarium wilt was examined in 216 melon germplasms by the root-dipping inoculation method with Fusarium oxysporum f. sp. melonis fungal isolate KACC43206 (race 2). Inoculated seedlings were incubated for four weeks and assessed for disease symptoms using indices ranging from index 1 (no symptoms) to 5 (plant wither). A total of 34 accessions showed a disease index < 2.0. Disease indices of 10 accessions were 1.0 four weeks after inoculation. The resistant accessions of melon are expected to help in breeding commercial varieties with Fusarium wilt resistance.

Background: Safflower is an important crop that does not require rich soils. It grows well in dry soils or arid areas with seasonal rain. Exploring the fatty acid profiles and agro-morphological characteristics of diversified collections of safflower provides baseline data for developing improved varieties. In this study, we investigated the variation in agro-morphological characteristics, fatty acid composition and total phenolic content of the seeds, and the relationship between the agro-morphological and biochemical characteristics. Methods and Results: Agro-morphological characteristics were recorded in the field and laboratory. Total phenolic content was estimated using Folin-Ciocalteu’s method and fatty acids were determined using gas chromatography-mass spectrometry. Orange, red, and white petal colors were observed; orange was the dominant pigment. Wide ranges of other agro-morphological characteristics were also recorded. More than 87% of the accessions contained > 50% linoleic acid while approximately 12% of the accessions contained > 50% oleic acid. A strong correlation was observed between palmitic and linoleic acid, and crude fat and oleic acid. A strong negative correlation was observed between crude fat and linoleic acid, palmitic and oleic acid, and oleic and linoleic acid. Conclusions: Safflower accessions were found to be a poor indicator of essential linolenic acid. The wide variation in agro-morphological and biochemical traits of safflower accessions could potentially help to develop an improved, nutrient-dense safflower cultivar.

Lettuce is an important dietary source of bioactive phytochemicals. Screening and identification of the health beneficial metabolites and evaluating the relationships with phenotypic characters can help consumers adjust their preferences for lettuce plant types. Thus, we explored the major health-beneficial individual metabolites and antioxidant potential of 113 red pigmented lettuce leaf samples. A UV–Vis spectrophotometer and UPLC-DAD-QTOF/MS (TQ/MS) instruments were used for the identification and quantification of metabolites and antioxidant activity accordingly. The metabolites were quantified against their corresponding external standards. The contents of metabolites varied significantly among lettuce samples. Cyanidin 3-O-(6″-O-malonyl)glucoside (4.7~5013.6 μg/g DW), 2,3-di-O-caffeoyltartaric acid (337.1~19,957.2 μg/g DW), and quercetin 3-O-(6″-O-malonyl)glucoside (45.4~31,121.0 μg/g DW) were the most dominant in red pigmented lettuce samples among anthocyanins, hydroxycinnamoyl derivatives, and flavonols, respectively. Lettuces with dark and very dark red pigmented leaves, circular leaf shape, a strong degree of leaf undulation, and highly dense leaf incisions were found to have high levels of flavonoids and hydroxycinnamoyl derivatives. Principal component analysis was used to investigate similarities and/or differences between samples, and the partial least square discriminant analysis classified them into known groups. The key variables that contributed highly were determined. Our report provides critical data on the bioactive constituents of red pigmented lettuce to breeders developing varieties with enhanced bioactive compounds and to nutraceutical companies developing nutrient dense foods and pharmaceutical formulations.

Watermelon (Citrullus lanatus) is a non-seasonal, economically important, cucurbit cultivated throughout the world, with Asia as a continent contributing the most. As part of the effort to diversify watermelon genetic resources in the already cultivated group, this study was devoted to providing baseline data on morphological quality traits and health-beneficial phytonutrients of watermelon germplasm collections, thereby promoting watermelon research and cultivation programs. To this end, we reported morphological traits, citrulline, and arginine levels of watermelon genetic resources obtained from the gene bank of Agrobiodiversity Center, Republic of Korea, and discussed the relationships between each. Diverse characteristics were observed among many of the traits, but most of the genetic resources (>90%) were either red or pink-fleshed. Korean originated fruits contained intermediate levels of soluble solid content (SSC) while the USA, Russian, Tajikistan, Turkmenistan, Taiwan, and Uruguay originated fruits had generally the highest levels of soluble solids. The citrulline and arginine contents determined using the High Performance Liquid Chromatography (HPLC) method ranged from 6.9 to 52.1 mg/g (average, 27.3 mg/g) and 1.8 to 21.3 mg/g (average, 9.8 mg/g), respectively. The citrulline content determined using the Citrulline Assay Kit ranged from 6.5 to 42.8 mg/g (average, 27.0 mg/g). Resources with high citrulline and arginine levels contained low SSC, whereas red- and pink-colored flesh samples had less citrulline compared to yellow and orange.