. 2021 Sep 16;6(38):25076–25088. doi: 10.1021/acsomega.1c04396

Table 3. Effect of Different Concentrations of Heavy Metals on Plant Growth Regulating Substances Synthesized by E. cloacae Strain MC9^a.

		plant growth regulating substances
		siderophore production
treatment	concentrations (μg mL^–1)	FeCl₃ test	siderophore (% unit)	zone size on CAS agar (mm)	NH₃ production	HCN production
Cd	25	++	76	16	++	+
	50	+	69	14	+	+
	100	+	54	12	–	–
	150	–	39	10	–	–
	200	–	22		–	–
Cr	25	++	81	16	++	+
	50	+	65	15	+	+
	100	+	52	13	+	+
	150	+	36	12	–	+
	200	–	28	10	–	–
Pb	25	++	80	15	++	+
	50	+	73	12	+	+
	100	+	54	13	+	+
	150	+	43	10	–	+
	200	–	18		–	–
Ni	25	++	91	17	++	++
	50	+	82	16	+	+
	100	+	76	15	+	+
	150	+	56	13	+	–
	200	–	43	12	+	–
control		++	95	18	++	++

Each value is a mean (mean ± SD) of three independent replicates. Symbols + and – represent the positive and negative reactions, respectively.

Table 3. Effect of Different Concentrations of Heavy Metals on Plant Growth Regulating Substances Synthesized by E. cloacae Strain MC9a.