Changes in proteins and starch granule size distribution during grain filling of triticale

PÉREZ, G. T.; RIBOTTA, P. D.; AGUIRRE, A. V.; RUBIOLO, O. J.; LEÓN, A. E.

AGRISCIENTIA

Facultad de Ciencias Agropecuarias, Universidad Nacional de Córdoba

Lugar: Córdoba; Año: 2004 vol. 21 p. 13 - 21

0327-6244

Changes in protein fractions and starch granule size distribution were evaluated throughout grain filling, from 14 to 47 days after anthesis (DAA) for two lines (T and B) of triticale (X Triticosecale Wittmack). Synthesis of the albumin-globulin fraction decreased during grain filling while prolamin and glutelin synthesis increased. Significant differences were found in protein content at different stages of synthesis between the two lines, T and B, the B line showing a faster rate of synthesis. As developmental grain approached physiological maturity, there was an increasing proportion of the large polymers separated under unreducing multistacking gel electrophoresis. The small polymer and protein subunit separated in 12% resolving gel decreased in T but did not change in B line from 14 DAA until physiological maturity. The size distribution of starch granules of both triticale lines was characterized during grain filling, by using a light-scattering particle size analyzer. A bimodal size distribution was found. The percentage volume of the large granule decreased and the small granule increased during ripening. In B line, starch granules were smaller and showed a higher percentage volume than those of the T line. The result observed in protein synthesis and granule size suggests that the differences between the two lines could be related with the high shriveling level of B line grains.Triticosecale Wittmack). Synthesis of the albumin-globulin fraction decreased during grain filling while prolamin and glutelin synthesis increased. Significant differences were found in protein content at different stages of synthesis between the two lines, T and B, the B line showing a faster rate of synthesis. As developmental grain approached physiological maturity, there was an increasing proportion of the large polymers separated under unreducing multistacking gel electrophoresis. The small polymer and protein subunit separated in 12% resolving gel decreased in T but did not change in B line from 14 DAA until physiological maturity. The size distribution of starch granules of both triticale lines was characterized during grain filling, by using a light-scattering particle size analyzer. A bimodal size distribution was found. The percentage volume of the large granule decreased and the small granule increased during ripening. In B line, starch granules were smaller and showed a higher percentage volume than those of the T line. The result observed in protein synthesis and granule size suggests that the differences between the two lines could be related with the high shriveling level of B line grains.