Tyrosine-priming modulates phenylpropanoid pathway in maize grown under different pH regimes

Abstract

Alkaline and acidic pH of soil limit crop yield. Products of phenylpropanoid pathway play a key part in plant abiotic stress tolerance. It was aimed to assess efficacy of tyrosinepriming for activation of enzyme involved in phenolic accumulation induction of pH tolerance in maize seedlings. Seeds of two maize cultivars, namely Sadaf (pH tolerant) and S-2002 (pH sensitive), were grown under three pH levels (3, 7 and 11). Eight and twelve days old seedlings were harvested and parted into roots and shoots for the assessment of growth, enzymatic and non-enzymatic antioxidants. PAL activity was directly correlated with total soluble phenolics, flavonoids, growth and seedling vigour. Lower accumulation of phenolics and PAL activity in the pH sensitive (S-2002) cultivar indicated greater oxidative damage caused by pH extremes. Priming improved antioxidative potential by enhancing PAL activity and phenolics accumulation and hence increased growth in maize seedlings.

Acid Rain Increases Impact of Rice Blast on Crop Health via Inhibition of Resistance Enzymes

“…Acid rain pollution could have effects on plant diseases by altering physiological metabolism and/or disease resistance systems of the host [ 17 , 18 ]. The antioxidant system appears especially sensitive to acid rain [ 10 , 19 , 20 ]. Previous studies have shown that P. oryzae combined with acid rain can induce rice plants to activate the defense system, improve the activity of plant peroxidases (POD) and phenylalanine ammonia-lyase (PAL), and stimulate the production of polyphenolic compounds, thus improving the plant resistance to stress [ 21 , 22 ].…”