Bloei en bloeislaging van de robusta koffie op Sumatra's Westkust

W.J. Deenen

Research output: Thesisinternal PhD, WU


As an insight into flowering and fruit yield the percentage of flowers yielding fruits was estimated. To allow for variation between branches, many flowers must be taken. The extent of flowering of robusta coffee depended on the relation between vegetative and generative growth, both showing a maximum and a minimum, while factors favouring one were often adverse-for the other. The physiological condition of the trees strongly influenced fruit setting. Stephanoderes hampei F. may penetrate berries 3-5 months old. Consequently rotting and damage may lead to a considerable fall. This fall depended much on the condition of the tree and not on the number of S.hampei. Falling was also favoured by sunny and dry periods.
A good regular shading promoted flowering and fruit production, due mainly to a better water supply preventing yellowing and dying of the leaves. Too much shading may be harmful to the generative growth, so pruning must lead to more light during wetter months. For a better water supply the humus content of the soil could be improved. The percentage fruit set of primary, secondary, upper, medium and low branches showed that 'topping', preventing water shortage in dry periods, was not harmful for fruit set. Lower trees also facilitate the control of S.hampei and the harvesting.
Original languageDutch
QualificationDoctor of Philosophy
Awarding Institution
  • Wageningen University
  • van der Stok, J.E., Promotor, External person
Award date30 Jan 1936
Place of PublicationWageningen
Publication statusPublished - 30 Jan 1936
Externally publishedYes


  • coffee
  • flowering
  • sumatra
  • netherlands east indies

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