Abstract
Moisture Effect on Physical Properties of Knotweed (Polygonum cognatum Meissn.) seeds
In this study, the effects of moisture content on some of physical properties of madimak (Polygonum cognatum Meissn.) seeds were investigated. Moisture contents of seeds were 7.95, 13.68 and 19.14% d.b. (dry basis), respectively. The average geometric mean diameter, unit mass, sphericity, thousand-seed mass and angle of repose ranged from 1.85 to 1.94 mm, 0.0040 to 0.0046 g, 66.21 to 67.37%, 3.32 to 3.74 g and 18.36 to 25.00° as the moisture content increased from 7.95 to 19.14% d.b., respectively. Bulk density and porosity were decreased from 696.11 to 707.73 kg m-3, 57.93 to 40.16%, whereas the seed volume, true density and surface area were increased from 3.357 to 3.894 mm3, 1654.69 to 1182.64 kg m-3, and 10.786 to 11.867 mm2 as the moisture content increased, respectively. The static coefficient of friction on various surfaces linearly increased with an increase in moisture content. Since madimak seeds are in small sizes, they can easily be separated at higher moisture contents which will also help planting of small seeds and enhance germination rate.
Keywords
Madimak (Polygonum cognatum Meissn.), seeds, moisture content, physical properties
