FIGURE 4.

The JA receptor COI1 is not required for nectar secretion, but is required for the nectary auxin response. The ‘young’ flowers of opr3-1 (A) and coi1-1 (B) do not produce nectar, whereas the corresponding ‘old’ flowers secrete nectar. ‘Old’ opr3-1 flowers (with nectar) display a strong auxin response in nectaries (A, lower right), but the corresponding ‘old’ coi1-1 flowers with nectar do not (B, lower right). The expression of key genes involved in nectar secretion was examined in whole flowers by qRT-PCR in both ‘young’ (no nectar) and ‘old’ (with nectar) of opr3-1 (C) and coi1-1 (D). qRT data was normalized to Col-0 (dashed line).