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NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.



In a further study to assist in estimating the profitability of insect control measures [cf. F.A. 30 No. 6021], 2-year-old Pinus patula plants were artificially defoliated in the rainy and the dry seasons at localities in Kenya, Uganda and Tanzania. Complete defoliation caused a reduction in height and diameter growth of ca. 50% for the year in question. With a few exceptions, ca. 50% defoliation, removing either (a) the youngest, or (b) the oldest foliage, did not significantly reduce growth, nor were there significant differences between (a) and (b). Trees defoliated at the start of the dry season recovered more slowly and showed a greater loss of growth than those defoliated at the end of the dry, or during the rainy season. Growth reduction by short-term 50% defoliation would seem to be economically tolerable, in that measures to prevent it would be uneconomic.