The effect of different sources of rice (Oryza sativa cv. Ember)
residues; straw, dry root, burned straw, and burned root on wheat
(Triticum aestivum cv. IPA) and barley (Hordeum vulgare cv. Local)
germination and seedling growth was investigated. Extracts of residues
were used at concentrations of 1%, 2%, and 4% (w:v). Whole residues
were used at rates of 10, 20, and 40 g/kg soil. Seed germination, shoot and
root length, reduction in dry weight , chlorophyll content, and electrolyte
leakage from leaf cells expressed as injury were measured.
The results showed as the concentration of the extracts or rate of whole
residues increased, all the growth parameters studied decreased also in
both crops except injury to seedling which increased in proportional to
increasing concentrations. Ground root extracts and whole residues were
the most effective in reducing germination, root length , shoot length,
chlorophyll content and dry weight. For whole residues, burned root was
superior in increasing injury to wheat leaves while ground root was more effective in increasing injury to barley leaves. For the interaction, ground
root extract at 4% or ground root of whole residues at 40g/kg soil had the
most inhibitory effect in most cases. |