Early growth of a germinated wheat seed was characterized with changes in vermiculite water potentials (W -0.03 to -1.10
MPa) and pots depth (10 to 30 cm). Deionized water was added in vermiculite for a desired W treatment. Germinated seeds
of 5-mm radicles were planted in pots and glass boxes. Experiments were conducted in controlled condition in a growth
chamber. Periodic samples were taken on each sampling day to measure roots and shoot of young wheat plant. Leaf area was
markedly sensitive to decrease in W from -0.03 to -0.60 MPa with no leaf visibility at W -1.10 MPa in 25 days old seedlings.
Dry matter (DM) decreased by reducing W, but this reduction in DM was associated to both shoot and roots losses. DM of seedhull
increased by decrease in W. No changes in DM were observed in early 7 days growth at W -0.03 and -0.15 MPa. Seminal
roots number did not differ at higher W but markedly decreased at low W. The root length showed a linear reduction by
decrease in W from -0.03 to -1.10 MPa. Root branch length also shrank markedly at high (W -0.03 to -0.06) to moderate
(W -0.60 to -1.10) decrease in W. Root length to weight ratio was linear but negatively related to decrease in W with a
linear positive change with time after the seed transplanting. Osmotic potential and tissue moisture content declined in a
linear fashion by the decrease in W for different parts. DM of shoot and roots was observed in exponential fashion to DM of
seed-hull and time to the transplanting. A linear but negative relationship was noted for shoot and roots to seed-hull
fractional contribution in DM (FCDM). The study suggests marked sensitivity of root and shoot to reduction in W in the
early development stages of wheat plant. Reduction in W markedly decreased roots and branch number and their length,
which inhibited leaf initiation.
Mohammad Akmal, Muhammad Afzal, Tadashi Hirasawa. (2015) Evaluation Of Stand Establishment And Growth Performance Of Wheat In Response To Different Water Potential Levels, , Volume-52, Issue-3.
