Concentration-dependent effects of exogenous phytomelatonin on flowering and physiological changes in azaleas (<i>Rhododendron maculiferum</i>)

Figures (6) Tables (1)

Figure 1.
Effect of different concentrations of melatonin on the flowering period of Rhododendron maculiferum 'Pink Round Cluster'. (a) Phenotypic changes after different MT treatments. (b) Flowering last days. (c) Advance flowering time.
Figure 2.
Effect of different concentrations of MT on endogenous nutrients in Rhododendron maculiferum 'Pink Round Cluster'. (a) Soluble sugar content. (b) Soluble protein content.
Figure 3.
Effect of different concentrations of MT on anthocyanin content of Rhododendron maculiferum 'Pink Round Cluster'.
Figure 4.
Effect of different concentrations of MT on endogenous hormone content in Rhododendron maculiferum 'Pink Round Cluster'. (a) IAA content. (b) GA₃ content. (c) ABA content. (d) ZR content.
Figure 5.
Effect of different concentrations of exogenous MT on endogenous MT content in Rhododendron maculiferum 'Pink Round Cluster'.
Figure 6.
Correlation analysis between physiological indicators and endogenous hormone content.

Treatment	MT concentration (μmol·L⁻¹)	Initial flowering date	Full bloom date	Flower diameter (cm)	Flowering duration (d)	Advance flowering duration (d)	Flowering rate (%)
CK	0	20 March	12 April	7.56 ± 0.27 f	17 ± 3.17 e	−	68.89 ± 2.35 f
MT1	100	10 March	31 March	7.89 ± 0.23 d	26 ± 1.99 c	10 ± 0.37	78.22 ± 1.26 d
MT2	300	6 March	28 March	8.23 ± 0.12 b	32 ± 2.13 a	14 ± 0.85	86.69 ± 2.33 b
MT3	500	13 March	31 March	8.66 ± 0.33 a	26 ± 2.88 c	7 ± 1.22	88.78 ± 2.88 a
MT4	1,000	20 March	10 April	7.61 ± 0.13 e	25 ± 1.89 d	0 ± 3.18	82.33 ± 2.56 c
MT5	3,000	28 March	16 April	8.13 ± 0.23 c	28 ± 2.33 b	– 8 ± 0.98	78.56 ± 3.25 d
MT6	5,000	1 April	18 April	7.84 ± 0.09 d	28 ± 1.98 b	−10 ± 1.87	72.68 ± 2.82e

Table 1.

Effect of different concentrations of melatonin (MT) on flowering period and flower quality of Rhododendron maculiferum 'Pink Round Cluster'.