G. Karimzadeh et al., Low temperature-induced accumulation of protein is sustained both in root meristems and in callus in winter wheat but not in spring wheat, ANN BOTANY, 85(6), 2000, pp. 769-777
Plant growth was assessed and cellular protein per nuclear DNA amount measu
red in root meristems and in callus derived from embryos of a spring ('Kate
pwa') and a winter variety ('Beaver') of allohexaploid wheat exposed to low
temperature treatment. The data obtained were used to test whether these g
enetically distinct varieties of wheat responded differentially to cold tre
atment. Seedlings were grown for 14 d at 20 degrees C and then transferred
to 4 degrees C for 14 d before returning them to 20 degrees C, or else were
maintained continuously at 20 degrees C. In winter wheat, root growth at 4
degrees C was significantly greater over the first 7 d following transfer
to 4 degrees C compared with plants retained at 20 degrees C, whereas in sp
ring wheat it was reduced at 4 degrees C. The pattern of accumulation of ce
llular protein for both root meristem cells and in callus cells was also ge
nerally enhanced at 4 degrees C compared with 20 degrees C in winter wheat
but not in spring wheat. Thus, clear inter-varietal differences were establ
ished both for dry weight accumulation and cellular protein, and the callus
data clearly show that the low-temperature-induced accumulation of protein
is a cellular phenomenon nor necessarily linked to development. The extent
to which cold-shock proteins are a component of this low temperature-induc
ed increase in cellular protein is discussed. (C) 2000 Annals of Botany Com
pany.