Regarding to the fact that ADP project, launched in September 1998, has to build the ways for a fixed and profitable agriculture, preservative of the environment in central region of Vietnam to increase rural development, the objectives of research component are to create technological offers - in terms of rubber based farm systems - adapted to a great variety of social and ecological situations and to assure the efficiency of the diversification's ways through an implication of beneficiaries. The main strategies previously defined were: i) Research in controlled environment on rubber tree, associated crops and crops systems. ii) Adaptive research designed to check the agricultural techniques in different farms conditions. iii) Participatory research designed to fit the technical innovations to the farmers needs and to promote its appropriation. The activities of the research component were carried out along 3 axes as presented in the scientific programs for the previous years 1999, 2000 and 2001: (i) the approaches about the understanding of the environment and the socio-economic conditions, (ii) the demonstration of innovating agronomic techniques based on no tillage and direct seeding techniques while (iii) experimentation on rubber agricultural techniques was still continued. Unfortunately the project conditions did not allow us to carry out participatory research, mainly because the farming systems study, first step of an agro-economical diagnosis is still not started and moreover farmers have a little margin of decision in the use of production factors provided by project (credit access and land). This report presents the activities on agro-technical references, focused on soil fertility management and rubber based cropping systems mainly carried out in Chu Prong station (Pleiku) and began in T.T. Hue province as OFT.