PREFACE

Ongoing research in this field continues to produce surprises. For example, many natural products are proving to have bioregulating activity. Some, such as jasmonic acid, salicylic acid, Ca⁺⁺ ion, brassinosteroids, triacontanol and other alcohols, oligosaccharide, etc. are likely to prove useful in the production of horticultural crops. They may act as second messengers in regulating gene expression and/or plant responses to environmental stimuli. Some new discoveries relating to well known bioregulators are equally astounding. The concept of a growth-inhibiting gibberellin is indeed revolutionary and teaches us that there is still much to be learned about even the most researched families of plant bioregulators.

Based on this background, the symposium organizers arranged the topics to achieve both immediate impact and lasting influence by providing a glimpse of the future. Rather than providing an overview of plant growth regulator usage, the topics are focused on theoretical and philosophical aspects of some growth substances and their potential in horticultural production systems. The term ‘plant bioregulators’, therefore, is more appropriate than ‘plant growth regulators’ to reflect the nature of the symposium.

The invited papers were presented by prominent scientists engaged in fundamental, pioneering work with plant bioregulators who conveyed the relevance of their research to important horticultural problems or issues. The other papers, presented as contributed papers at Kyoto, were selected and edited by the symposium organizers for inclusion in this volume. An attempt was made to give equal representation to papers dealing with fruit, vegetable and ornamental crops.

The original symposium organizing committee was chaired by Dr. S. Kuraishi (Hiroshima University). Due to his sudden death in February, 1993, Dr. N. Nito was appointed to the committee and Dr. Looney assumed major responsibility for choosing speakers and editing the proceedings. Drs. Looney, Nevins and Nito served as moderators for the symposium, attended by about 120 scientists.

Sincere appreciation and cordial thanks are extended to all those who participated in this symposium and all those who helped with the preparations. We thank Dr. Anna M. Koltunow, Division of Horticulture, CSIRO, Australia, for reviewing some papers during her stay in Saga University after the Congress. We wish to thank, too, Mr. Y. Katayama, Saga University, for assistance in editing.

Norman E. Looney
Donald J. Nevins
Nobumasa Nito