. 2021 Apr 12;11:7992. doi: 10.1038/s41598-021-86401-0

Table 2.

Effect of PEG and its combination with NO and ABA (nitrate agonists) on total free amino acid, proline content, and activity of ∆¹-pyrroline-5-carboxylate synthetase (P5CS) and proline dehydrogenase (ProDH) of 7-days-old B. juncea L. roots after 96 h exposure to the treatments.

Treatments	Total free amino acids (mg g⁻¹ FW)	Proline content (µmol g^--1 FW)	P5CS activity (nmol NADPH oxidised min⁻¹ mg⁻¹ protein)	ProDH activity (nmol NADH formed min^-1 mg⁻¹ protein)
Control	6.9 ± 0.301^d	0.329 ± 0.045^e	30.4 ± 1.37^d	170.0 ± 8.92^a
NO	7.4 ± 0.333^cd	0.317 ± 0.033^e	29.5 ± 1.84^d	173.6 ± 7.33^a
ABA	7.0 ± 0.300^d	0.321 ± 0.042^e	29.1 ± 1.67^d	170.7 ± 7.77^a
PEG	12.7 ± 0.533^a	0.452 ± 0.040^a	48.8 ± 1.61^a	121.3 ± 6.45^e
PEG + NO	8.2 ± 0.411^c	0.401 ± 0.029^c	35.2 ± 1.46^c	158.3 ± 7.25^b
PEG + NO + ABA	8.8 ± 0.412^c	0.361 ± 0.035^d	39.6 ± 1.33^b	150.2 ± 7.17^c
PEG + ABA	9.6 ± 0.431^b	0.433 ± 0.042^b	41.1 ± 1.35^b	139.4 ± 5.83^d

Values are mean ± S.E. of three independent experiments, each including four biological replicates. Different letters represent significant difference between treatments, where “a” corresponds to the highest value and “d” or “e” to the lowest value.