PREFACE FROM THE EDITORS/ORGANIZERS

About a half year after the Sixth International Symposium on Pollination held in August 1990 in Tilburg, we are happy now to present the Proceedings. We feel that the Proceedings of the Symposium give an interesting reflection of the scientific meetings and discussions on the use of insects for pollination purposes. As Dr. Sv. Norgaard Holm indicated in his welcome address, several new scientific and practical developments in the field of insects pollination take place and with this book containing all the presented lectures and posters a valuable contribution to future research is to be expected.

It was the useful contribution of Dr. K. Brantjes who summerised the lectures presented during the symposium and his conclusions gave a clear reflection of the achievements of the symposium.

Regarding the lay-out of the submitted papers, we had to follow the guidelines of the publisher ISHS, which explains the slight changes we had to make in some of the manuscripts. Only a few manuscripts had to be retyped. We were very pleased with the technical help and advices from the International Society for Horticultural Science (ISHS) to put the Proceedings together. With the support of Mr van de Borg and his Secretariat an interesting addition to the series of Acta Horticulturae is realised.

Finally we would like to thank again all members of the organization teams who made it possible to have had this fruitful event.


Dr. Kees van Heemert

Drs Aad de Ruijter

Ambrosiushoeve
Ambrosiusweg 1
5081 NV Hilvarenbeek
The Netherlands


WELCOME ADDRESS

On behalf of the International Commission of Plant-Bee relationships it is a pleasure for me to welcome you to attend the Sixth International Symposium on Pollination.

The first symposium was held in Copenhagen, Denmark, in 1960 under the chairmanship of Professor Erik Akerberg, Sweden. Since then four well-attended international meetings have been held, and many research workers concerned with plant-bee relationships have been provided with the opportunity to meet and discuss with other specialists from all over the world.

It is my hope that these international meetings will continue in the future and contribute -as they have done in the past- to ensure that pollination continues to be regarded as an important field of research in connection with plantbreeding and cropproduction.

New perceptions produced by imagination and knowledge will be forthcoming and with the necessary investigative effort many of the ideas will ultimately lead to new pollination techniques and practices. In this context our meetings provide an excellent forum for the mutual exchange of ideas and methods.

New species of bees have been developed as pollinators of crop plants. This has only been possible with fundamental biological studies. At the present time yet other species of bees are being studied, and management programmes are being devised to maximize and assure adequate pollination of specific crops.

As an example, the bumble bee has been intensively studied for many years in an attempt to discover means of controlling and managing bumble bee colonies as we do with honeybees. These fundamental biological studies have now led to the practical use of bumble bee colonies for the pollination of tomato plants in glasshouses. Further investigations on bumble bees will undoubtedly lead to more adequate pollination of other crop plants in glasshouses as well as in fields.

I would like to take this opportunity to thank Dr. Kees van Heemert and his group of co-workers for organising this Sixth International Symposium in Tilburg. They have provided a framework of well-organised scientific and social programmes and congenial surroundings of our meeting. It is now up to the participants to fill out this framework. I thank you all for your interest in the symposium and wish you a successful and prosperous meeting.