Red peppers are a remarkable source of nutrients in the human diet. However, comprehensive studies have not reported on the effects of genotype, cultivation region, and year on pepper fruit characteristics. To address this, 12 commercial pepper varieties were grown at two locations in South Korea, during 2016 and 2017, representing four environments, and concentrations of proximate, minerals, amino acids, fatty acids, capsaicinoids, and free sugars in pepper pericarps were determined. Variation in most nutrients was observed among the 12 varieties grown within each location in each year, indicating a significant genotype effect. Statistical analysis of combined data showed significant differences among varieties, locations, and years for the measured components. The % variability analysis demonstrated that environment (location and year) and genotype-environment interaction contributed more to the nutritional contents than genotype alone. Particularly, variation in many amino acids, capsaicinoids, free sugars, and myristic acid was attributed to location. Year effect was significant for palmitoleic acid, ash, tryptophan, copper, linolenic acid, crude fiber, and tyrosine. Insoluble dietary fiber, soluble dietary fiber, sodium, sulfate, linoleic acid, and alanine were primarily varied by genotype–environment interaction. Palmitic acid was the trait the most highly affected by genotype. Cultivation and the genotype–environment interaction have a major role in determining the composition of 12 pepper varieties across four environments. The data from this study could explain the natural variation in the compositional data of peppers by genotypes and environments.

Red pepper is enriched in antioxidant components, such as carotenoids, phenolic compounds, and vitamins. In this study, we investigated the natural variability in the content of carotenoids and phenolic acids in 11 red pepper cultivars grown in two locations in South Korea during 2016, 2017, and 2018. Seven carotenoids and six phenolic acids, including soluble and insoluble forms, were detected in the red fruit pericarps. The major carotenoids were β-carotene (40%) and capsanthin (20%). The content of insoluble phenolic acids was higher than that of soluble phenolic acids because of the large amount of insoluble p-coumaric acid. The statistical analysis of combined data showed significant differences among varieties, locations, and years for most of the measured components. The results from variance component analysis indicated that the effects of location, year and the interaction of location and year mainly accounted for the variation in carotenoids, whereas variations in phenolic acid content were attributed to year and variety. In addition, the results of principal component analysis and orthogonal partial least-squares discriminant showed that carotenoids were well discriminated by location and year, whereas phenolic acids were distinctively separated only by year. The data from this study could explain the natural variation in the content of carotenoids and phenolic acids in red pepper fruits by genotype and environment.

To determine the effect of winter green manure crops for tillage and no-tillage organic pepper cultivation in plastic film house, five different green manure crops were cultivated during winter season. In nutrition composition of green manure crops, total nitrogen contents were higher in Vicia hirsuta and Vicia angustifolia than any other crops. The average dry weights of green manure crops were 8.3 ton per ha in tillage and 7.0 ton per ha in no-tillage, among green manure crops that of Secale cereale was the highest. Fertilizer supply was depended on the biomass of the cultivated green manure crops and nutrition contents, total nitrogen supply of V. angustifolia was 226 kg and that of S. cereale was 251 kg per ha in tillage field. In no-tillage field, N-supply of V. angustifolia was 197 kg and that of S. cereale was 222 kg per ha. In yield components of red pepper, fruit numbers per plant were 55.5 in green manure crop tillage and 37.0 in no-tillage cultivation. Among green manure crops, the yield of dried red pepper was the highest for V. angustifolia in both green manure crop tillage and no-tillage cultivation.

Tomato spotted wilt virus (TSWV) is a destructive viral pathogen in various crops, including pepper. While the single dominant gene Tsw has been utilized in pepper breeding to confer resistance to TSWV, the occurrence of TSWV variants that overcome Tsw-mediated resistance has been reported in various countries after several years of growing resistant cultivars. In this study, we determined the complete genome sequence of a resistance-breaking TSWV variant (TSWV-YI) that recently emerged in pepper in South Korea. TSWV-YI infected all the resistant pepper cultivars tested. The phylogenetic and recombination analyses of the complete TSWV-YI genome sequence showed that it is a reassortant that acquired its L and M RNA segments from the existing South Korean TSWV population and its S RNA in an isolate from another country. Given that TSWV-YI is a resistance-breaking variant, it appears that reassortment of the S RNA led to the emergence of this variant that breaks the Tsw gene in pepper grown in South Korea. Our results suggest that resistance-breaking TSWV variants are a potential threat to pepper production in South Korea and that strategies to manage these variants should be developed to ensure sustainable pepper production.

ABSTRACT. This study was conducted to predict the yield response of red pepper and to determine the economic weed threshold levels for red pepper cultivation field from competition with the most serious weeds, Amaranthus patulus and Digitaria ciliaris in Youngyang of Korea. Crop yield as a function of weed density was predicted by using a rectangular hyperbola, and their economic threshold levels were determined by using the equation developed by Cousens (1987). The red pepper yield loss models of weeds were predicted as y=304.7/(1+0.063x), R 이러한 잡초 발생으로 인한 작물 수량 감소 정도는 수 학적인 모델식을 이용하여 예측 하려는 노력이 다양하게 시도되었으며 (Cousens, 1985;Kropff and Spitters, 1991;Kropff et al., 1995;Berti and Sattin, 1996), 이러한 모델 들 가운데서 Cousens (