Alleviation of Lead Toxicity by 5-Aminolevulinic Acid Is Related to Elevated Growth, Photosynthesis, and Suppressed Ultrastructural Damages in Oilseed Rape

Table 1

Effects of treatments of 5-aminolevulinic acid (ALA) (mg L⁻¹) and lead (Pb) (μM) on plant height (cm), stem length (cm), root length (cm), and leaf area (cm² plant⁻¹) of Brassica napus L.

ALA conc.	Pb conc.	Mean values and their relative increase/decrease over respective controls
		Plant height	Stem length	Root length	Leaf area
0	0	44.73±2.83^a (0)	14.46±0.94^a (0)	18.22±1.17^b (0)	325.66±14.62^a (0)
	100	37.47±2.53^b (−16.22)	9.58±0.71^c (−33.74)	17.54±1.27^bc (−3.73)	223.09±14.59^c (−31.49)
	400	26.73±2.11^c (−40.24)	6.35±0.58^d (−56.08)	11.55±0.94^d (−36.61)	174.25±11.53^d (−46.49)
25	0	45.35±2.69^a (+1.38)	13.50±0.81^ab (−6.06)	18.65±1.31^b (+2.36)	333.14±12.98^a (+2.31)
	100	42.50±2.06^a (+13.42)	12.26±0.79^b (+27.97)	21.49±1.73^a (+22.51)	312.90±13.65^a (+40.25)
	400	37.51±1.00^b (+40.32)	10.42±0.73^c (+64.09)	15.39±1.03^c (+33.24)	265.66±13.27^b (+52.45)

Values are the means of four replications ± SD. Variants are significant at 𝑃≤0.05.