Glycosidases and acid-invertase activities are not correlated with Phaseolus hypocotyl growth

Abstract

Changes in c~-galactosidase, (~-galactosidase, g-glucosidase and acid invertase activities were examined in Phaseolus vulgaris hypocotyls treated with gibberellic acid (GA), naphthyl acetic acid (NAA) and distilled water (DW) (control) in light condition. The activities were estimated both in cytoplasmic and ionically wall-bound fraction. The upper segment showed considerable elongation growth while there was hardly any growth in lower segment. GA and NAA showed distinct promotion and inhibition respectively in hypocotyl growth in upper segment. The glycosidase activities were detected in both the fractions but the activity was more pronounced in cytoplasmic than in wall fraction. Acid invertase activity was present only in cytoplasmic fraction. In lower segment, in both cytoplasmic and wall fraction, the glycosidase activity, in general, showed a decreasing trend and no effect of treatment could be envisaged. In upper segment, though the trend was similar to the lower one, in (z-and g-galactosidase NAA treated segment had more activity. Invertase activity also did not show a clear trend to implicate its function in hypocotyl elongation growth. The results are discussed in relation to establishing a correlation between an activity (glycosidase and invertase) and a physiological process (hypocotyl elongation). It is concluded that these wall-loosening enzymes have no role in elongation growth of Phaseolus vulgaris hypocotyls.

The Effect of Soybean Mosaic Virus on the Activity of Carbohydrases in Leaves of Sensitive and Resistant Soybean Plants

“…5). In contrast to 1,3-β- The data of our investigations do not correspond to the results obtained with the bean hypocotiles (Bagatharia and Chanda, 1998). These authors deny the role of hydrolases as wall loosening enzymes.…”

“…These hydrolases may modify carbohydrates providing solidity and elasticity to the cell-wall. They can also participate in regulation of biological functions of such carbohydrates of cell wall as gemicellulose, callose, pectin polysaccharides, glycoproteins, glycosidese of flavonoids and other glycoconjugates (Srisomspar et al, 1996;Bagatharia and Chanda, 1998). There is no effect of virus infection on activities of these enzymes in soybean plants.…”