OPENING ADDRESS

I have the great honour to inaugurate the international scientific Symposium on Authomatic Control of Plant Growth and Yield Formation Processes and Computer-Aided Soil and Crop Management in Vegetable Production, which is being held jointl by the Institute of Vegetable Production Grossberen of the Academy of Agricultural Sciences of the German Democratic Republic and by the Internatioanl Societ for Horticultural Science.

I should like to welcom all of you most cordiall on behalf of the Presidium of the Academy of Agricultural Sciences of the GDR. We are pleased to see that guests from many countries have accepted our invitation to attend this scientific event. We esteem it an honour to have a number of prominet figures among us on this first day the Symposium. I welcome Mr. Klaus Haubold, member of the Central Committee of the Socialist Unity Party of Germany, Dr. Karl-Friedrich Gebhardt, Deputy minister for Agriculture, Forestry and Food of the GDR, Mr. Günter Zillmann, Deputy Minister for Science and Technology of thr GDR,and Dr. Thomas Naumann, member of the municipal Council of Berlin, in charge of agriculture, forestry anf food. We thank you for ypur participation which consider an expression of your high esteem for this international Symposium.

It gives great pleasure to welcome so many representativies and members of the International Society for Horticultural Science. I welcome most cordially Mr. van der Borg, General Secretary of the International Society for Horticultural Science and at the same time I should like to express my heartfelt thanks for his support during the preparations for this Symposium.

I also warmly welcome Prof. Dr. Skierkowski from Poland, Vice President of the ISHS Section of Vegetable Growing, Prof. Dr. Ottosson from Sweden, formerly Vice President of the same Section for many years, and the executive members of the International Society for Horticultural Science Prof. Dr. van Assche from Belgium and Prof. Dr. Crüuger from the Federal Republic of Germany.

I most cordially welcome to the German Democratic Republic the scientists from Belgium, Bulgaria, China, Czechoslovakia, the Federal Republic of Germany, Finland, Japan, Canada, the Netherlands, Poland, Sweden, Hungary and the Soviet Union. I wish all of you a pleasant stay in the German Democratic Republic.

I should like to extend a warm welcome to the scientists from the Academy of Agricultural Sciences and from universities, all those engaged in horticultural practice, and all other guests from this country.

Ladies and gentlemen,

The participation of scientists from so many countries is indicative of the fact that the automatic control of plant growth and yield formation processes in vegetable production is a highly topical scientific subject of global interest.

We are currently witnessing intensified efforts made by scientists to find ways and means for using computer-aided growth and yield control as a tool for increasing the efficiency of crop production.

The growing of horticultural crops of high value, particularly of vegetables and ornamental plants in greenhouses, calls for innovations. In the 1990s and beyond, the development of vegetable production will be decisively influenced and, to an increasing extent, dominated by such fields as

• Computer-aided control of plant growth and yield formation processes in greenhouses and soil and crop management in outdoor vegetable production;
• Computer-aided hydroponic techniques in greenhouses;
• Automated production systems using robots in greenhouses and, gradually, also outdoors.

The subject area of this international conference takes this trend into account. The before mentioned promising fields will increasingly have to rely on the precise measurement of the relevant quantities using sophisticated sensor systems. The great number of scientific meetings and symposiums held recently on the issue and the rapid growth of the number of scientific publications in the world are a reflection of this development.

It is not without reason that in the field of vegetable growing researchers are intensely working on the computer-aided control of the plant growth and yield formation processes in greenhouses and outdoors on the basis of mathematical models. Greenhouse plant production and outdoor vegetable production are known to show the highest level of intensity. The great expenditure on investments in greenhouse and outdoor production of vegetables, which is many times larger than in general plant production, as well as the labour- and energy-intensive nature of this industry really call for giving top priority to computer-aided growth and yield control. And this all the more as research and development in the fields covered by the Symposium are capable of producing significant effects in terms of better utilization of the yielding potential, increasing labour productivity and lower energy inputs. What is more, the production of vegetables outdoors and, particularly, in greenhouses offers the opportunity of controlling a great number of climatic and growth factors with microcomputers and automatic control systems. The specific features of outdoor vegetable production such as staggered and timed cropping, use of vegetable planting stock, temporal covering of the soil and the vegetables plants by plastic films or textile fleece, cold and controlled-atmosphere storage of vegetables, full irrigability of the vegetable fields, and others, give much more scope for control than is the case with, for example, the production of cereals, sugar beet or potatoes.

This makes clear how demanding the challenge to research workers is to do the scientific groundwork for the highly important field of growth and yield control.

In this spirit we hope and wish that the papers to be presented during our Symposium will make an important contribution to this end, stimulating new ideas and giving an impetus to further scientific work. I wish the international scientific Symposium, which is attended by 200 scientists from 15 countries, every success.

Prof. Dr. Drs. h.c.D. Spaar
President of the Academy
of Agricultural Sciences of the
German Democratic Republic