The Role Of Biological Nitrogen Fixation In The Cacao Agroforestry System In Central Sulawesi Indonesia

This international symposium featured three interconnected thematic foci of interdisciplinary research. They focussed on the changes in the extent and intensity of agricultural and forest land use in tropical forest margins and their implications for rural development and for conservation of natural resources such as biodiversity, soils and water. The symposium took place in Goettingen. Almost 130 international authors have contributed a short abstract and their adress.

Coffea arabica, one of the economically most important crops worldwide, occurs naturally in the undergrowth of montane rainforests of Ethiopia. The study provides the first detailed ecophysiological investigations of wild coffee populations. It demonstrates the inter- and intra-regional variability in phenotypic and hydrological characteristics of wild coffee. The results reveal very different strategies of wild coffee seedlings for coping with drought stress. The ecophysiological diversity shows the importance of Ethiopian wild coffee populations as gene pools for future breeding programs, and underlines the need for an in-situ conservation strategy. The study includes recommendations for coffee forest management and the use of wild arabica coffee in Ethiopia.

Solanum quitoense (Lulo) from the northern Andes is a fruit with an attractive taste. It has a high export potential but its production is hampered by insufficient pollination. Studies on the reproductive system of Lulo revealed that, due to their poricidal anthers, the flowers need pollinators for self- and cross-pollination. Pollination by native bumblebees significantly increases fruit set and quality. Experiments show that colonies of Bombus atratus can be reared in captivity and used in Lulo fields for providing increased pollination services. Modeling based on data on colony development reveal larva/workers ratio and the supply of pollen as main parameters for improving the rearing method.