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Title: A multifunctional role for riboflavin in the yellow nectar of Capsicum baccatum and Capsicum pubescens
Summary A fewCapsicum(pepper) species produce yellow‐colored floral nectar, but the chemical identity and biological function of the yellow pigment are unknown.A combination of analytical biochemistry techniques was used to identify the pigment that givesCapsicum baccatumandCapsicum pubescensnectars their yellow color. Microbial growth assays, visual modeling, and honey bee preference tests for artificial nectars containing riboflavin were used to assess potential biological roles for the nectar pigment.High concentrations of riboflavin (vitamin B2) give the nectars their intense yellow color. Nectars containing riboflavin generate reactive oxygen species when exposed to light and reduce microbial growth. Visual modeling also indicates that the yellow color is highly conspicuous to bees within the context of the flower. Lastly, field experiments demonstrate that honey bees prefer artificial nectars containing riboflavin.SomeCapsicumnectars contain a yellow‐colored vitamin that appears to play roles in (1) limiting microbial growth, (2) the visual attraction of bees, and (3) as a reward to nectar‐feeding flower visitors (potential pollinators), which is especially interesting since riboflavin is an essential nutrient for brood rearing in insects. These results cumulatively suggest that the riboflavin found in someCapsicumnectars has several functions.  more » « less
Award ID(s):
2025297
PAR ID:
10514800
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
New Phytologist
Volume:
243
Issue:
5
ISSN:
0028-646X
Format(s):
Medium: X Size: p. 1991-2007
Size(s):
p. 1991-2007
Sponsoring Org:
National Science Foundation
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