Table 2.

Genes of interest with direct roles in nectar production with relative expression values from our transcriptomic dataset, putative roles, and relevant citations.

Gene	SDE	Putative Role	Citation
CWINV4	≈	Hydrolyzes sucrose into fructose and glucose; knockouts do not produce nectar	Ruhlmann et al., 2010
SBE2.2	≈	Involved in starch synthesis; upregulated early in development in ornamental tobacco	Ren et al., 2007
BAM1	↑S1 vs S2/S3	Starch breakdown; upregulated during secretory stage in Cucurbita pepo	Solhaug et al., 2019
PIN6	↓S3 vs S1/S2	Expression level is positively correlated with nectar production in Arabidopsis	Bender et al., 2013
MYB21	↑S2 vs S1/S3	Induces negative feedback loop on jasmonate biosynthesis	Reeves et al., 2012
SWEET9	↓S3 vs S1/S2	Required for nectar secretion in Arabidopsis	Lin et al., 2014
JAZ	↓S3 vs S1/S2	Represses jasmonic acid (JA) signalling in a negative feedback loop	Chico et al., 2008
GA2ox6	↑S2 vs S1/S3	Inactivates gibberellic acid (GA), which increases expression of genes involved in nectar production	Wiesen et al., 2016
JMT	↑S2 vs S1/S3	Forms Methyl Jasmonate from JA; JA conjugates are linked to increased nectar production.	Radhika et al., 2010

SDE, Significant Differential Expression with arrows representing either up or down regulation of expression between developmental stages (≈ indicates no SDE). S1, pre-anthetic nectary; S2, anthetic nectary; S3, post-anthetic nectary.