Fruit Morphology, Citrulline, and Arginine Levels in Diverse Watermelon (Citrullus lanatus) Germplasm Collections

Abstract

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.

Current Evidence of Watermelon (Citrullus lanatus) Ingestion on Vascular Health: A Food Science and Technology Perspective

“…In these studies, watermelon was ingested as juice [ 4 , 26 ], extract [ 1 , 11 ], puree [ 27 ], and microencapsulated [ 28 ], all of which are natural sources of L-citrulline that could improve vascular health. Although in smaller amounts than L-citrulline, watermelon also contains L-arginine, an amino acid that is directly involved in NO synthesis [ 29 ]. As mentioned above, eNOS uses L-arginine as a substrate to produce NO and L-citrulline.…”

Estimation of Cold Stress, Plant Age, and Number of Leaves in Watermelon Plants Using Image Analysis

“…Watermelon (Citrullus lanatus) is a highly nutritious fruit comprised of 93% water with small quantities of protein, fat, minerals, and vitamins. It is widely considered a functional food, thus contributing to its widespread consumption around the world (Assefa et al, 2020). Watermelon is a member of the cucurbit family (Curcurbitaceae), which are chill-sensitive plants that are native to subtropical and tropical regions around the world.…”

Variability of Agro-morphological Character and Genotype Clustering of Watermelon [Citrullus lanatus (Thunberg) Matsum & Nakai] as Basic Selection for New Variety

“…It is possible that there are variations in the diversity of agro-morphological characters between genotypes of watermelons, in which the more variety and genetic distance between genotypes, the more options available to breeders to assemble varieties. Information on the characteristics of plant traits and methods of breeding in an effort to improve plant traits can be seen through genetic parameters, such as variability of character, heritability and genetic progress (Assefa et al, 2020;Mahla & Choundhary, 2013).…”