Foliar spray of selected plant growth regulators affected the biochemical and antioxidant attributes of spinach in a field experiment

Authors : MARYAM ASLAM, BUSHRA SULTANA, FAROOQ ANWAR, HASSAN MUNIR

Pages : 136-145

View : 14 | Download : 9

Publication Date : 2016-04-01

Article Type : Research Paper

Abstract :This study explored the effects of foliar spray of selected plant growth regulators insert ignore into journalissuearticles values(PGRs); on the biochemical and phenolic antioxidant attributes of spinach insert ignore into journalissuearticles values(Spinacia oleracea); leaves. Following foliar spray at three growth stages insert ignore into journalissuearticles values(40, 50, and 60 days); with selected PGRs, namely humic acid insert ignore into journalissuearticles values(HA);, Moringa oleifera leaf extract insert ignore into journalissuearticles values(MOLE);, and 6-benzylamino purine insert ignore into journalissuearticles values(6-BAP);, and their mixed form, the samples of spinach leaves were harvested. The analysis of foliar-treated leaves revealed the content of proline, malondialdehyde insert ignore into journalissuearticles values(MDA);, total soluble proteins insert ignore into journalissuearticles values(TSPs);, total chlorophyll, and total carotenoids to be 22.45-72.32 μg/g FW, 2.41-29.13 ng/g FW, 3.21-22.45 μg/g FW, 4.173-19.700 mg/g FW, and 0.500-1.260 mg/g FW, respectively. The total phenolic content insert ignore into journalissuearticles values(TPC);, reducing power, and DPPH° scavenging activity insert ignore into journalissuearticles values(IC50 values); varied from 6.59 to 14.49 mg GAE/g DM, from 0.426 to 1.944 insert ignore into journalissuearticles values(10.0 mg/mL extract concentration);, and from 0.506 to 1.073 μg/mL, respectively. HPLC analysis showed that foliar application of PGRs also improved the content of individual phenolic acids in the leaves as compared with the controls. Overall, it was concluded that, although the use of the PGRs acted as an elicitor with respect to each growth phase and exhibited significant differences insert ignore into journalissuearticles values(P < 0.05); among treatments, the leading effect was exhibited by the MOLE treatment, proving it to be a better enhancer of phenolic antioxidants and other biochemicals.
Keywords : Spinach, humic acid, Moringa leaf extract, chlorophyll, antioxidant activity, HPLC, phenolic acids