Evaluation of forty-five cultivars as affected by bulb initiation, bulb and scale characteristics, and bulb minerals and organic compounds of intermediate-day yellow onion (Allium cepa L.) in South Korea

Abstract

We evaluated and classified forty five onion cultivars according to bulb initiation, bulb and scale characteristics, minerals and organic compounds contents, and storage quality in South Korea during 2016/2017 and 2017/2018 growing seasons. Field experiment was conducted in randomized block design with three replications. Bulb initiation ranged from 153 days after transplanting (DAT, April 2) to 177 DAT (April 26). Fresh bulb weight (FBW) and bulb index (BI) were 285.5 ± 18.5 g/ individual, 0.93 ± 0.05, respectively. Number of scales (NS), number of center (NC), and scale thickness (ST) were 7.6 ± 0.2, 2.3 ± 0.2, and 5.5 ± 0.2 mm/scale, respectively. Chroma and Lightness of bulb skin were 27.1 ± 1.9, 61.2 ± 2.3, respectively. Storage loss (SL) on December 12 was 19.4 ± 5.9%. Nitrogen (N), Carbon (C) and sulfur (S) contents were 1.36 ± 0.14, 37.9 ± 3.2 and 0.40 ± 0.06 mg kg −1 on a fresh weight basis. Total soluble solids (TSS) and total phenolics content (TPC) were 8.6 ± 0.6 °Bx, 164.8 ± 15.6 mg GE kg −1 on a fresh weight basis. Days from transplanting to bulb initiation was significantly positively correlated with bulb height, NC, dry matter, N, C, S, TSS, TPC, total flavonoids content (TFC) etc., while it was negatively correlated with rot loss and SL. Dry matter content was significantly positively correlated with N, C, S, TSS, TPC, TFC etc., while it was negatively correlated with SL. Storage loss was negatively correlated with N, S, Potassium and TSS. Dendrogram of agglomerative hierarchical clustering for the forty five cultivars based on bulb initiation, bulb and scale characteristics, and bulb minerals and organic compounds contents classified five cultivar groups. Cluster 1 featured the earliest bulb initiation and the greatest SL. Cluster 2 featured the fewest NS and NR, and the thickest ST. Cluster 3 featured the greatest FBW, and the most NS and NC. Cluster 4 featured the greatest BI and the thinnest ST. Cluster 5 featured the lowest SL, and the highest minerals and antioxidant compounds contents. This information should be helpful for onion growers to decide onion cultivar and for onion breeders to promote new cultivars depending on their purpose.

Planting Date and Different N-Fertilization Rates Differently Modulate Agronomic and Economic Traits of a Sicilian Onion Landrace and of a Commercial Variety

“…Furthermore, the number of fleshy scales was also highly affected by genotypical differences [11,54]. Differences were found between the two accessions, according to the results from Bal et al [55], Petropoulos et al [11], and Lee et al [48]. The results from this study agree with those of Sinkovič et al [56], who found that the average number of fleshy scales was higher for plants not subjected to nitrogen fertilization.…”

“…In contrast, Gererufael et al [36] found an increase in the dry matter content as the N dose increased. Furthermore, Ncayiyana et al [37], Mogren et al [13], and Lee et al [48] found significant differences in the percentage of dry matter in various cultivars of onion.…”

“…The variability in the biometric and production parameters found in various onion cultivars and accessions which have been the subject of research in various parts of the world is linked to differences in the genetic heritage and environmental factors [45,46]. As noted by a number of authors [47][48][49], the adaptability of cultivars and the different pedoclimatic conditions found at the test sites and in the many regions in the world where onion farming is particularly widespread have significantly affected production and quality results.…”

Effects of the Application Times and Strength of Additional Fertilizers on Onion Bulb Quality Parameters at Harvest and during Storage

“…Furthermore, onion cultivars responded differently to the strength of nitrogen fertilization in terms of marketable yield and total yield (Díaz-Pérez et al, 2003). In detail, bulb quality characteristics including fresh bulb weight, bulb height and diameter, dry matter and so on were highly fluctuated by onion cultivars at harvest (Lee et al, 2020). Meanwhile, potassium fertilization linearly affected plant growth characteristics, including plant height, leaf number, leaf length, bulb length, bulb diameter, and mean bulb weight (Bekele, 2018).…”

Estimation of Garlic’s Bulb Weight at Harvest Using a Multi-level Model Based on Growth and Meteorological Data

“…일장을 조절하며 양파 구 비대에 미치는 영향력을 분석한 연구 (An and Suh, 2013)가 있었으며, 양파 주산지의 단수와 기상자료를 활용하여 공간가중패널회귀모형을 통해 단수를 추정 한 연구 (Choi and Baek, 2016b)가 있었다. 또한, 생육기 온도 상승이 극조생 양파의 생육과 구 비대에 미치는 영향 검증 (Song et al, 2017), 고온과 다습조건이 양파 생육 및 수량에 미치는 영향력 규명 (Lee et al, 2019), 양파 구 특성 및 유기물 함량 등에 따른 품종 평가 및 분류 (Lee et al, 2020) 1-수준 모형은(Eq. 1) 생육 자료의 개체 단위 모형으로, 최종 구중과 개체별 생육자료와의 회귀분석 모형이다.…”