LADIES AND GENTLEMEN

Most of you know about the activities of the International Society for Horticultural Science. We work with objective of the scientific and technological development of horticulture by increasing the international cooperation. Science is universal and therefore scientists and horticulturists can not stay isolated from the world around. All of you that work in horticulture are welcome as members of the ISHS.

The ISHS activities are expanding outside Europe to South America, Africa, and Far East. Being an international society we must be where horticulture industry is and not only in those countries with an older tradition of research. That is why many symposia, as this one, are held outside Europe.

The ISHS is organized in sections, commissions and working groups according to the major branches and the most important disciplines of horticultural science. The Commission Protected Cultivation deals with all aspects of protected cultivation of vegetables, flowers, and fruits. The Working Group for Protected Cultivation in Mild-winter Climates has been created within the Commission Protected Cultivation owing to the specificity of protected cultivation in the mild-winter conditions, using simple plastic structures adapted to the favourable climate. The technology used in the heated glasshouses is unsuitable for our conditions. The philosophy of mild-winter is to get advantage of the climate in order to lower the investments and the production cost.

However, the greenhouse production system is changing very rapidly in the more advanced countries: the international market is imposing higher standards for quality; the trading agents and the governments are each time more concerned with consumers health and with the control of chemical residues; the citizens are very conscious of the environmental impact of agriculture, and we know that some types of protected cultivation are not very environmental friendly; higher productivity is required through a more efficient use of production factors to stay competitive in the international market.

In conclusion I would say that the mild-winter production system must be improved to keep in pace with the market evolution. That is why the Working Group Protected Cultivation in Mild-Winter Climates is encouraging the evolution of the system. If no strong technological development is introduced in the existing greenhouse cropping system it risks to become obsolete in the near future.

Up till now the Working Group has focused in symposia with broad subjects. The idea was to put together different systems. But once the knowledge of the system is progressing more specialized symposia are needed.

The I.S.H.S. Symposium on Soil and Soilless Media under Protected Cultivation in Mild-Winter Climates is the first specific symposium we are organizing.

Scientists and horticulturists working in protected cultivation tend to focus their attention mainly on greenhouse climate. It is logical since the major change in comparison with the open-field is the modified climate. However, it is often forgotten that in our conditions most of the cropping problems arise form the soil. Salinity, soil diseases, poor drainage, and nutritional disorders, for instance, can affect crop productivity and quality. It is useless to improve greenhouse climate if the soil is the limiting factor. That is why soil has been chosen as main subject for this meeting.

The present production system can not make progress towards higher crop quality and productivity without improving the greenhouse soil cultivation methods or introducing soilless cultivation. We will have time during the symposium to discuss these possibilities.

There is no better place for discussing soil related aspects than Egypt, a country with 5000 years of experience on irrigated horticulture. We are in the right place to deal with the right subject. I anticipate that many interesting ideas will come during the next few days. We will have time both for indoor sessions and for technical visits to growers and to the Protected Cultivation Project.

Before finishing my talk I must thank the organizing committee, specially Dr. Ayman Abu-Hadid and his co-workers for all the work they have done during the last several months for organizing this symposium. It was an idea that we both discussed 2 years ago and I am very happy that it has come true.

On behalf of the International Society for Horticultural Science and personally as well I welcome all of you to this symposium. I am sure that it was worth coming to Cairo under the professional and under the personal points of view. Horticulture is our work, but it is also the place where we have many friends of us. I wish that this symposium be also and occasion to make new friends and to improve the cooperation for a better protected cultivation.

Thank you

António A. Monteiro
Chairman W.G. Protected Cultivation in Mild-Winter Climates


CONCLUDING REMARKS

The ISHS Symposium on soil and soilless media under protected cultivation in Mild winter climates have taken place in Cairo, from 1–6 March 1992 and hosted by Ministry of Agriculture and Land Reclamation.

In attendance of 67 participants from 21 countries, and papers dealt with 10 different subjects related to soil and soilless media in protected cultivation.

This distinguished gathering of scientists from the international comity have discussed the oral presentations given by the invited speakers and the contributed papers.

The following remarks can be drown from the sessions:

1. Nutrient film technique is a power full tool for crop cultivation as well as research work to estimate water and nutrition consumption. Attention should be directed in the future to measure water consumption for different crops as a tool to estimate crops water requirement under plastic houses. Also, attention to the problems facing root development should be emphasized. It is important to stress upon the flexibility of NFT system and the possibility for its utilization in different conditions.
2. Soil pests and diseases were illustrated and the different techniques to combat and overcome their harmful effects were discussed. It is quite important to stress upon the use of safe methods in pest management and to minimized chemical usage. Integrated pest management schemes need to be developed to reduce the impact that pesticide misuse has on the environment and human health.
3. Soil and nutrition aspects were discussed as were the evaluation of crop nutrition requirement related to different crops and growth stages. The need to introduce computerized system or automated systems for nutrition is obvious and efforts towards the establishment of a nutrient requirement curve is needed. Studying the possibilities of using bio-fertilizers under protected cultivation was mentioned.
4. Soil-based substrates: Sand can be a good alternative as a media for hydroponics. The experience of Spain and Egypt in this respect can be a good base to use this soil based substrate.
5. Soil salinity has its impact on plant growth and development. Although it is in a way reducing the yield potentials, but moderate salinity can be useful for improving plant hardness and fruit quality. Studies on ethylene in relation to salinity may pave the road towards the use of saline soil by avoiding stressful conditions.
6. Water management for greenhouse crops is a crucial element in order to improve plant productivity and quality it was recognized that without proper water management, it is not possible to advice for nutrition, salinity control, or even plant diseases control. The use of weighing lysimeter to estimate crop water requirement was described and may be advised as a research and control unit.
7. Substrates:

   The substrates for soilless culture are essential elements for the development of greenhouse industry in mild winter climates. Some substrates are quite useful in this respect and the possibilities of new substrates were discussed.

8. Modifying plant to suit the environment is as important as modifying the climate itself. For this, breeding programs for salt tolerance, disease resistance, heat stress or chilling stress is required to improve plant materials for greenhouses under winter climate. Equally, modifying the climate to reduce the evapotranspiration is advisable in order to increase the water use efficiency and maximize the yield per cubic meter of water as well as per square meter of land. It is, also, mentioned that some chemicals may prove useful to improve plant performance under low and high temperatures. Such materials may be of great help for future cultivations after being tested in the climate of mild winters.
9. Temperature differences can affect seedling growth, especially cucumber. Moreover, climate modification can improve productivity through enhancing the mechanisms which affect fruit growth and development.

As an activity of the working group protected cultivation in mild winter climate and the commission protected cultivation, the Ministry of Agriculture and Land Reclamation in Egypt have hosted the ISHS Symposium on Soil and Soilless Media Under Protected Cultivation in Mild Winter Climates. The symposium have been held in Cairo, Egypt during 1–6 March 1992. Over 60 participants from Italy, Spain, Portugal, Greece, Turkey, U.K., Lebanan, Saudi Arabia, Tunisia, Chili, Cyprus, France, Finland, Netherland, USA, Japan and Egypt have participated in the symposium,

Over 40 paper and poster have been presented in the symposium sessions. Ten top-notch scientist from different countries have been invited to participate in the symposium, sessions which covered the following topics:

• General Aspects of Soil and Soilless Cultivation.
• Artificial Media for Soilless Culture.
• Nutrient Film Technique Application and Problems.
• Soil based Substrates.
• Soil Salinity and Water Management.
• Soil Pests and Diseases.
• Soil Kinetics Related to Protected Cultivation.
• Industries Related to Protected Cultivation.

Symposium sessions lasted for four days including 21 scientific sessions followed by a couple of field trips to private sector farm, Governmental farm and an integrated farm.

The following remarks have been drown from the sessions:

1. Nutrient film technique is a powerful tool for crop cultivation as well as research work to estimate water and nutrition consumption. Attention should be directed in the future to measure water consumption for different crops as a tool to estimate crops water requirement under plastic houses. Also, attention to the problems facing root development should be emphasized. It is important to stress upon the flexibility of NFT system and the possibility for its utilization in different conditions.
2. Soil pests and diseases were illustrated and the different techniques to combat and overcome their harmful effects were discussed. It is quite important to stress upon the use of safe methods in pest management and to minimize chemical usage. Integrated pest management schemes need to be developed to reduce the impact that pesticide misuse has on the environment and human health.
3. Soil and nutrition aspects were discussed as were the evaluation of crop nutrition requirement related to different crops and growth stages. The need to introduce computerized system or automated systems for nutrition is obvious and efforts towards the establishment of nutrient requirement curves are needed. Studying the possibilities of using biofertilizers under protected cultivation was mentioned.
4. Sand can be a good alternative as a media for hydroponics. The experience of spain and Egypt in this respect can be a good base to use this soil based substrate.
5. Soil salinity has its impact on plant growth and development. Although it is in a way reducing the yield potentials, but moderate salinity can be useful for improving plant hardness and fruit quality. Studies on ethylene in relation to salinity may pave the road towards the use of saline soil by avoiding stressful conditions.
6. Water management for greenhouse crops is a crucial element in order to improve plant productivity and quality, it was recognized that without proper water management, it is not possible to advice for nutrition, salinity control, or even plant diseases control. The use of weighing lysimeter to estimate crop water requirement was described and may be advised as a research and control unit.
7. The substrates for soilless culture are essential elements for the development of greenhouse industry in mild winter climates. Some substrates are quite useful in this respect and the possibilities of new substrates were discussed.
8. Modifying plant to suit the environment is as important as modifying the climate itself. For this, breeding programs for salt tolerance, disease resistance, heat stress or chilling stress is required to improve plant materials for greenhouses under winter climate. Equally, modifying the climate to reduce the evapotranspiration is advisable in order to increase the water use efficiency and maximize the yield per cubic meter of water as well as per square meter of land. It is, also, mentioned that some chemicals may prove useful to improve plant performance under low and high temperatures. Such materials may be of great help for future cultivations after being tested in the climate of mild winters.
9. Temperature differences can affect seedling growth, especially cucumber. Moreover, climate modification can improve productivity through enhancing the mechanisms which affect fruit growth and development.

The proceeding of the symposium is now in preparation to be published in the Acta Horticulturae.