STUDY OF THE ANATOMICAL STRUCTURE ALONG THE OIL PALM FRUIT BUNCH STALK AND ITS IMPACT ON CUTTING PRESSURE

The variation in anatomical characteristics of 16-year-old African oil palm fruit bunch stalk and its effect on mechanical cutting were investigated.Variations in vascular bundle (VB) density, VB size, parenchyma tissue area ratio, and total cross-sectional area along the length of the fruit bunch stalk were analysed.The correlation between cutting pressure and the corresponding anatomical structures was then established.Results show that vascular bundle density decreases from the proximal to distal positions of the fruit bunch stalk, whereas total cross-sectional area and vascular bundle size increase from the proximal to distal positions.The variation of the parenchyma tissue area ratio does not vary significantly.Multivariate regression analysis shows a positive correlation between VB density and VB size with cutting pressure (R 2 = 0.741), with the influence of VB density on cutting pressure being much larger than the effect of VB size.From the results of complete fruit bunch stalk cutting, it is found that the required cutting pressure is lowest when cutting at the middle section of the stalk, halfway between the stalk ring and the fruit bunch rachis.