O estresse salino retarda o desenvolvimento morfofisiológico e a ativação de galactosidases de parede celular em caules de Vigna unguiculata

Abstract

ABSTRACT(Salt stress delays morphophysiological development and activation of cell wall galactosidases in Vigna unguiculata stems). In order to examine the participation of α-and β-galactosidases in the cell expansion of stems from cowpea seedlings submitted to salt stress during plant establishment as well as to analyze the eff ect of salt stress on the development of seedlings and enzymatic activities, Pitiúba cowpea seeds were sown in distilled water and in 100 mM NaCl. Th roughout seed germination and seedling development, stems were harvested from seedlings at diff erent stages of development and at diff erent times aft er planting. Growth was evaluated by measuring stem length and fresh and dry mass of stems. Salinity both inhibited and delayed the growth of seedling stems. Th e eff ects of NaCl on galactosidase activities of the cell wall were studied, both in vivo and in vitro. Galactosidase activities in vivo were related to eff ects of NaCl inhibition and delay of stem development. Th e increase in salt concentration inhibited isolated galactosidase activity of cell wall from stems of seedlings. Starting at 250 mM NaCl, β-galactosidases were more sensitive to salt than α-galactosidases.

Effect of salt stress on the growth of Lippia gracilis Schauer and on the quality of its essential oil

“…In that same species, Taarit et al (2010) observed a more dramatic (61%) decrease in plants exposed to 100 mM of NaCl. According to Sudério et al (2011), salinity affects plant growth by impeding cell elongation, a process mediated by alpha-and beta-galactosidases. Those authors demonstrated that high salinity levels reduce the activity of these enzymes, resulting in delayed stem growth in Vigna unguiculata seedlings.…”

Antioxidant activity and physiological performance of popcorn seed after saline stress and analysis of seedling images

“…Salinity is important abiotic stress that affects production in several regions. It is aggravated by inadequate agricultural practices, especially those associated with irrigated agriculture (Sudério et al, 2011). Popcorn is grown in the second harvest and often with the use of irrigation.…”