The role of enzyme amylase in two germinating seed morphs of Halopyrum mucronatum (L.) Stapf. in saline and non-saline environment

Acta Physiologiae Plantarum (Impact Factor: 1.31). 01/2011; 33(4):1185-1197. DOI:10.1007/s11738-010-0646-z

ABSTRACT The role of enzyme amylase in two germinating seed morphs, i.e. black and brown, of Halopyrum mucronatum in saline and non-saline environment was examined. Both seed morphs of this halophytic grass have variations in their moisture
content, total lipid, protein, sugar, phenol and tannin contents. Black seed exhibited higher activity compared to brown in
saline medium. Sugar mobilization in both seed morphs was also affected due to the difference in amylase activity. However,
exogenous application of GA3 in saline medium enhanced the amylase activity and sugar mobilization. Phenolic contents were similar except for vanillic
acid which was found only in brown seeds while catechol was present only in black seeds. Phenols extracted from both seed
morphs were applied to determine their effects on amylase activity. Phenolic extracts obtained from brown seeds showed higher
degree of inhibition of amylase activity. Results are discussed in relation to seed coat phenols, leaching, amylase activity
and sugar mobilization.

KeywordsAmylase–Phenols–Seed types–Leaching–Germination–Response

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