title: A cell wall extract from Piriformospora indica promotes tuberization in potato (Solanum tuberosum L.) via enhanced expression of Ca(+2) signaling pathway and lipoxygenase gene.
abstract: Piriformospora indica is an axenically cultivable phytopromotional endosymbiont that mimics capabilities of arbuscular mycorrhizal fungi. This is a basidiomycete of the Sebacinaceae family, which promotes growth, development, and seed production in a variety of plant species. We report that the cell wall extract (CWE) from P. indica induces tuberization in vitro and promotes tuber growth and yield in potato. The CWE altered the calcium signaling pathway that regulates tuberization process. An increase in tuber number and size was correlated with increased transcript expression of the two Ca(2+)-dependant proteins (CaM1 and St-CDPK1) and the lipoxygenase (LOX) mRNA, which are known to play distinct roles in potato tuberization. External supplementation of Ca(2+) ions induced a similar set of tuberization pathway genes, indicating presence of an active Ca(2+) in the CWE of P. indica. Since potato tuberization is directly influenced by the presence of microflora in nature, the present study provides an insight into the novel mechanism of potato tuberization in relation to plant-microbe association. Ours is the first report on an in vitro tuber-inducing beneficial fungus.
authors.affiliation: Department of Botany, Guru Ghasidas Central University, Bilaspur 495009, India. cpupadhyay@gmail.com
authors.forename: Chandrama Prakash
authors.initials: CP
authors.lastname: Upadhyaya
authors.forename: Mayank Anand
authors.initials: MA
authors.lastname: Gururani
authors.forename: Ram
authors.initials: R
authors.lastname: Prasad
authors.forename: Ajit
authors.initials: A
authors.lastname: Verma
mesh_terms: D001487:Basidiomycota / Q000737:chemistry*; D001685:Biological Factors / Q000494:pharmacology; D002118:Calcium / Q000494:pharmacology; D020013:Calcium Signaling; D002473:Cell Wall / Q000737:chemistry*; D003470:Culture Media / Q000737:chemistry; D004789:Enzyme Activation; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D054884:Host-Pathogen Interactions; D008084:Lipoxygenase / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics; D035281:Plant Tubers / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011198:Solanum tuberosum / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000254:growth & development
chemical_list: D001685:Biological Factors; D003470:Culture Media; D010940:Plant Proteins; D012333:RNA, Messenger; D008084:Lipoxygenase; D002118:Calcium