Heritability and Genetic Variance Components Associated with Citrulline, Arginine, and Lycopene Content in Diverse Watermelon Cultigens

Abstract

<jats:p>Citrulline, arginine, and lycopene are naturally occurring compounds found in watermelon, <jats:italic>Citrullus lanatus</jats:italic> (Thumb) Matsum &amp; Nakai, with beneficial effects on plant growth and human health. This study evaluated seven commercial cultivars and one breeding line for citrulline, arginine, and lycopene content in mature fruit grown at two locations in North Carolina. Correlations among these compounds and fruit quality traits (percent soluble solids and flesh pH) were evaluated. Watermelon cultigens evaluated were chosen for their fruit trait diversity. ‘Yellow Doll’ and NC-517 possessed the highest citrulline and combined concentration of citrulline and arginine of all cultigens evaluated. Lycopene content was highest in ‘Dixielee’, followed by ‘Sugar Baby’, and ‘Allsweet’, each of which have different shades of red flesh color. Location and its interaction with genotype had no significant effect on arginine or lycopene concentration. Broad-sense heritability was estimated for each trait. Arginine content (89%) and lycopene content (99%) had very high heritability. Citrulline content (41%), percent soluble solids (46%), and flesh pH (61%) had moderate heritability. Lycopene was positively correlated with flesh pH (<jats:italic>r</jats:italic> = 0.517) and negatively correlated with percent soluble solids (<jats:italic>r</jats:italic> = −0.344). Arginine content had a weak negative correlation with flesh pH (<jats:italic>r</jats:italic> = −0.343) and was not correlated with percent soluble solids.</jats:p>

Citrulline and Arginine Content of Taxa of Cucurbitaceae

“…The negative correlations of SSC to citrulline and cit+arg across cucurbits contradicts the moderate positive correlations reported previously in a watermelon heritability study [37]. Given the wide array of cultigens, correlations here may be affected by our choice of cucurbit species to test.…”

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

“…The WF, SSC, length, and width of the fruit had also shown quite a wide diversity, but the medium character was common in most of the accessions. The average values of SSC, thickness of the outer layer of the pericarp, and length and width of fruits are comparable with previous reports; however, the fruit weight and size of the pistil scar were higher in the resources investigated in our study [ 8 , 20 , 21 , 22 , 26 ].…”

Citrulline and Arginine Are Moderately Heritable in Two Red-fleshed Watermelon Populations

“…Genetic variance was present for all six quality traits in both the parents and the offspring of the two populations studied (Table 1). For citrulline, there are several studies that report variation among and within cultigen in different environments, including that of Davis et al (2011) andWehner et al (2017), which prompted this study.…”

“…Zhang et al (2010) reported the general combining ability and heritability of lycopene, which were relatively high, suggesting a potential additive effect due to dominant genes. A study considering broad-sense heritability of fruit quality traits in a variety of red, orange, and yellow flesh found that arginine and lycopene were highly heritable (89% and 99%, respectively) (Wehner et al, 2017). Broadsense heritability for citrulline, pH, and SSC was low to moderate (41%, 61%, and 46%, respectively) (Wehner et al, 2017).…”

“…A study considering broad-sense heritability of fruit quality traits in a variety of red, orange, and yellow flesh found that arginine and lycopene were highly heritable (89% and 99%, respectively) (Wehner et al, 2017). Broadsense heritability for citrulline, pH, and SSC was low to moderate (41%, 61%, and 46%, respectively) (Wehner et al, 2017). However, there have been no studies reporting narrow-sense heritability of lycopene, citrulline, or arginine in watermelon.…”