Determination of Shear Strength, Tensile Strength, Shear and Picking Energy of the Petals and Sepals for Damask Rose

Knowing physical and mechanical properties of the flowers is one of the important factors in designing، harvesting and post harvesting machines. A completely randomized design with factorial test was used in this research. Effect of shear speed، flower diameter، blade mode and shear angle on shear strength and shear energy per stem area unit and effect of picking speed and petal diameter on petal and sepal on the tensile strength and energy consumed per unit of area were determined for Rosa damascena Mill. Shear strength was decreased by increasing shear angle from zero to 25 and 45 degree but it was not significant. Energy per unit of stem area and elastic modulus were decreased by increasing shear angle and it was significant at 5% probability level. Increasing shear speed from 150 to 250 mm/min was not significant on decreasing shear strength and elastic modulus but was significant at 5% probability level for 350 mm/min. Energy per unit of stem area was decreased by increasing shear speed. Shear strength، elastic modulus and shear energy per stem area unit were decreased by increasing flower diameter. Two treatments (Picking speed and flower diameter) were not significant on the tensile strength and picking energy per unit for both picking petal and sepal.