AUTHOR=Shukla Pushp Sheel , Prithiviraj Balakrishnan 

TITLE=Ascophyllum nodosum Biostimulant Improves the Growth of Zea mays Grown Under Phosphorus Impoverished Conditions

JOURNAL=Frontiers in Plant Science

VOLUME=11

YEAR=2021

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2020.601843

DOI=10.3389/fpls.2020.601843

ISSN=1664-462X

ABSTRACT=<p>Phosphorous is one of the major limiting factors determining plant growth. Current agricultural practices mainly rely on the use of chemical fertilizers posing threat to the ecosystem. In this study, the application of an <italic>Ascophyllum nodosum</italic> extract (ANE) in phosphorous (P)-limited conditions improved the fresh and dry weight of shoots and roots of <italic>Zea mays</italic>. ANE-treated <italic>Z. mays</italic> grown under P-limited conditions showed a higher P content than the control. ANE activated simultaneous responses, at multiple levels, in <italic>Z. mays</italic> grown under P-limited conditions as seen from the regulation of gene expression at the whole-plant level to specific biochemical responses on a subcellular level. ANE-supplemented <italic>Z. mays</italic> grown under P-limited conditions also showed reduced electrolyte leakage and lipid peroxidation by an improved membrane stability. ANE treatment reduced P-limitation-induced oxidative damage in <italic>Z. mays</italic> by reducing H<sub>2</sub>O<sub>2</sub> and <inline-formula><mml:math id="M1" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msubsup><mml:mrow><mml:mtext>O</mml:mtext></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow><mml:mrow><mml:mo>-</mml:mo></mml:mrow></mml:msubsup></mml:math></inline-formula> accumulation. Furthermore, ANE also induced the accumulation of the total contents of soluble sugars, amino acids, phenolics, and flavonoids. Gene expression analysis suggested that ANE differentially modulated the expression of P-starvation responsive genes involved in metabolic, signal transduction, and developmental pathways in <italic>Z. mays</italic>. ANE also modulated the expression of genes involved in sugar, lipid, and secondary metabolism. Thus, this study illustrated the role of ANE in improving the productivity of <italic>Z. mays</italic>, an important crop, in P-limited conditions. Furthermore, it sets the framework to increase agricultural productivity in nutrient deficient soils using a sustainable, eco-friendly strategy.</p>