Pakistan Journal of Biological Sciences1028-88801812-5735Asian Network for Scientific Information10.3923/pjbs.2003.640.643kunM. Bulent Co7200367This study was made in order to determine how much the type of cotton affects the design parameters such as vacuum pressure, suction speed and break-off force in a simple cotton picking machinery. The vacuum pressure, suction speed and curl break-off forces belonging to the cotton types of DPXxC//BixLa hybrid and Nazilli 84 which is still being developed in accordance with the mechanical harvesting were measured. The statistical relationships between measured design parameters and cotton variety were searched. It was observed that there is no statistical difference between types in aspect of suction speed and values of vacuum pressure where as the types differ in aspect of lock break-off force. The lock break-off force of the type of Nazilli 84 was been found lower than the kind which is still being developed. Although the break-off forces of cotton variety are different it is observed that suction speed of 2 m s-1 in average and a vacuum pressure of -5 kPa is sufficient for the locks to be broken off from the bolls.]]>Dilbaeck, R.E. and J.E. Quisenberry,197919567567Evcim, H.U.,19961996Evcim, H.U. and E. Oz,19971997Kaynak, M.A., 2001Gossypium hirsutum L.).]]>2001Onal, I.,19951995Sabanci, A. and A. Isik,19891989Tuncer, K. and A. Isik,19991999Yelin, D.,1985Gossypium hirsitum L.]]>1985