Mechanical damage to pinto beans as affected by moisture content and impact energy

Abstract

 Mechanical damage to seeds due to harvest, handling and other process is an important factor that affects the quality of seeds.  Seed damage results in lower grain value, storability problem, and reducing of seed germination and seedling vigor and subsequent yield of crops.  Tests were conducted to determine the extent of percentage of physical damage (PPD) and percentage of loss in germination (PLG) (physiological damage) of pinto beans due to impact.  The effects of beans moisture content (9.25%, 12.51%, 15.02% and 17.50%, wet basis) and impact energy (0.09 J, 0.19 J and 0.29 J) were determined.  The tests were conducted under laboratory conditions, using an impact test apparatus.  Results showed that effects of moisture content and impact energy on seed damages were significant.  PPD of beans was higher than PLG.  It found that the total damage of beans increased from 54.45% (48.14% PPD and 6.31% PLG) to 73.20% (63.40% PPD and 9.80% PLG) as the impact energy increased from 0.9 to 0.29 J, for all the moisture contents used.  With increasing the moisture content from 9.25% to 17.50%, the mean values of the percentage of loss in germination of beans increased from 0.53 to 15.30%.  However, by increasing in the moisture from 9.25% to 17.50%, the mean values of percentage of physical damage to beans decreased from 92.67% to 21.53%.

Keywords: physical damage, reduce in germination, moisture content, impact energy, pinto bean