FRO - Forest Range Organization
NDP - National Project Director
SPII - Seed and Plant Improvement Institute
The Eurasian species of the walnut tree (Juglans regia) grows naturally in Iran, especially in the north and west of the country. Domestication of this species, which has been cultivated for centuries, is mainly for nut production, but the timber of mature trees is highly valued and provides an important additional source of income for private growers.
Walnut plantations in 1987 covered 13 000 ha and produced 33 000 t of nuts. In 1995, 30 000 ha were covered and nut production was up to 100 000 t.
There is considerable genetic variability in seedling populations in terms of fruit-bearing capacity, vigour, tree shape and fruit shape and size. This has caused great variation in nut quality and has led to lower market prices than those commanded by walnut producers in the United States or France.
In order to identify superior walnut genotypes and ensure that superior cultivars get into general production, a walnut research programme was set up by FAO, UNDP, and the Ministry of Agriculture. This was implemented by the Ministry of Agriculture's research body, the Seed and Plant Improvement Institute (SPII), together with the Forest Range Organization (FRO), utilizing walnut genotypes selected by the SPII in 1986.
The Project Document for project IRA/89/029, "Walnut Improvement Research and Plantation Programme Development", was signed on 9 October 1990. It was due to start in January 1991 and scheduled to take three years. Owing to delays in the purchase of equipment and arrival of the experts, the project became operational in 1992 and was completed in December 1996. The budget, which was originally estimated to be $US 362 136, was shared by UNDP and the Government, which contributed $US 107 136 (in cash) and Rls 160 million (in kind). The UNDP input was revised from $US 255 000 to $US 264 735.
The development objectives of the project were to generate superior walnut cultivars in Iran by strengthening the applied research capacity of the SPII; to test grafting techniques to determine the best walnut seedlings for the Iranian climate; and to produce the selected genotypes for general distribution to growers. This information would then be used to prepare a large-scale plan for development of walnut plantations in Iran.
The project's immediate objectives were to support research activities in order to make sound recommendations leading to the improvement of walnut production in Iran; and prepare a walnut sector development programme.
Before embarking on the programme, the National Project Director (NPD) and three Iranian walnut experts took part in a three-week training tour to three European research institutions. The delegation visited the Mas Bove de Reus in Spain, the Esta�ao Nacional de Fruticultura de Alcoba�a in Portugal and the Station de recherches fruiti�res de Bordeaux in France in 1993. The study tour covered topics such as methods of walnut selection, walnut propagation, orchard mechanization, post-harvest operations, pest, disease and weed control, and watering methods.
Four sites with temperate climates (between 1 000 and 1 500 m above sea level), were selected by the SPII and the FRO to carry out experiments in propagation techniques and trials for the genetic evaluation of selected walnut genotypes. The Horticultural Department of Karaj was chosen for propagation experiment and germplasm collection. The Khorasan Agricultural Research Centre in Mashad featured a research farm and a tissue culture laboratory. The Agricultural Research Centre in Shahroud offered a 400 ha research farm and laboratory facilities for nut analysis. The West Azerbajan Agricultural Centre in Oromieh, with 5 ha of research farm, was chosen for the agronomic evaluation of trees.
The aims of the research were to prospect local seedling populations, variety and rootstock selections, to evaluate the selected genotypes and introduce foreign varieties, to experiment in grafting techniques and scion-producing mother plants and, finally, to distribute the selected genotypes to growers.
The following local genotypes were selected as a result of intense research activity: K21-3/2 (earliest fruit bearing); G3, Z63, K21/3, K37/1 (highest productivity); K143/2, K144/3, K143/1, K114/3, K135/3 (latest leafing out); G10, G3, K21/3 (highest lateral fruit bearing). Starting from 250 preselected genotypes, additional research was undertaken. Four promising clones, B21-1/3, G3, Z60 and Z63, were identified.
The following experimental trials were planned and executed to identify the best grafting technique suitable for walnut producing areas in Iran.
The hypocotyl grafting technique, performed in a greenhouse on potted seedlings had a success rate of 70 to 75% but the grafted plants were slow to grow. When directly applied in the field (under tunnels), there was a severe decrease in graft-take.
The patch-budding, T-budding and chip-budding techniques were investigated by reproducing favourable micro-climatic conditions or by applying hormone treatment during grafting. The graft-take rate observed at Karaj was no higher than 50% and the grafted seedlings were slow to grow.
The hot callusing system was performed in different ways. A 50% graft-take rate resulted from callusing the graft-union of the bench grafted plants in a therm-hygrometric controlled room. The rate increased to 75% when the plants were grafted and callused in the hot callusing pipe. With both techniques, however, seedlings grew extremely slowly in the first two years and there was a low survival rate, in particular for plants callused in the climatic room.
It was found that grafting and callusing the seedlings directly in the field by applying a heating cable around the graft-point, increased the graft-take rate to 75% and the plants were marketable 9 months later.
In 1995 and 1996 the SPII's nursery in Karaj produced and distributed 20 000 ungrafted superior seedlings and 3 000 grafted plants of the promising clones B21, G3, Z60 and Z63.
In order to collect additional observations the selected genotypes were distributed over different testing areas through the extension service offices and walnut cooperatives. Several stocks of grafted plants were also distributed directly to growers.
Several seminars were organized to train technicians and growers and to discuss the aims and results of the walnut project.
Seminars and workshops were held by the NPD and international consultants to discuss the project, to demonstrate the techniques used in experimental fields and to disseminate the results to Iranian walnut experts and growers.
The NPD and the head of the Karaj Horticultural Department attended the XXIV International Horticultural Congress held in Kyoto, Japan, in August 1994 to discuss the project's preliminary results. In June 1995, the NPD took part in the International Walnut Congress held in Lisbon, Portugal, in order to discuss the main results of the project on propagation techniques and genotype selections. In September 1996, the NPD presented the final results of the project to the First Horticultural Science Congress of Iran, held in Tehran.
The walnut project introduced important theoretical and practical methodologies. Newly developed theories were used to select new walnut genotypes, and to evaluate the genetic parameters of selected clones. The promising clones, selected for lateral fruitfulness, were an important contribution to walnut production because they induced early fruit and high yields.
The experimental grafting techniques performed at the Horticultural Department of Karaj could be introduced in Iranian nurseries. The hot callusing grafting method applied in the field, performed for the first time in the world, demonstrated the significant potential of this technique for the Iranian climate.
Dissemination of information, through workshops and seminars and through visits to the four pilot centres, was key to eliminating residual prejudice in walnut growers regarding plant propagation and planting techniques.
The SPII has provided strong leadership in implementing the project. There is a serious risk, however, that acquired know-how could be lost in the future owing to the fact that most of the trained walnut staff have come to the end of their term.
In order to ensure continuity, the Government should strive to keep trained personnel in office for several years and train new generations of technicians and researchers. Pilot cooperatives, farmers and modern nurseries should be involved. The training should take place under the supervision of the four research centres selected by SPII.
Training courses should deal with modern grafting techniques and orchard management. In addition, the germplasm collections made by the four research centres should be further investigated to study genotypes more thoroughly and to identify other promising clones.
The correct propagation of selected clones and newly-introduced foreign varieties is essential. Nurseries unable to reproduce perfectly the selected material should not be included in future projects envisaged by the national walnut programme.
Considering that the programme is developing nut production which is suitable for international competition, long-term action should include the training of Iranian experts in nut packing and marketing procedures to prepare the nuts for the foreign market. In the view of European and US markets, quality does not mean only nut size but also low levels of fungicides or insecticides. Iranian growers should receive strict recommendations on the correct use of pesticides.
Name Function Dates of Service
International
E. Germain Expert in walnut
genotype selection 1992 (2 weeks)
1996 (2 weeks)
D. Avanzato Expert in hot callusing
and patch budding 1994 (7 weeks)
1995 (2 weeks)
1996 (3 weeks)
D. Frutos Expert in hypocotyl grafting 1995 (2 weeks)
National
Atefi National Project Director 1992 - 1996
Escandali Assistant to NPD 1992 - 1993
Shafi Assistant to NPD 1994 - 1995
Hassan Assistant to NPD 1995 - 1996
Djavaherdeh Head of walnut programme, Sharout 1992 - 1996
Alizadeh Head of walnut programme, W.Azerbajan 1992 - 1996
Attard Head of walnut programme, Mashad 1992 - 1996
Mozzafari Head of walnut programme, Kerman 1992 - 1996
Mostafavi Horticultural consultant 1992 - 1995
Puran Irrigation consultant 1992 - 1996
Nematzadeh Technician at Karaj 1992 - 1996
Table ronde avec les representants de la cooperative des producteurs de noix de Shahmirzad. E. Germain (Semnan, 1992).
Expos� sur les recherches men�e sur le noyer et la culture de cette specie en France.
E. Germain (Sharout, 1992).
Workshop on walnut production in Iran and presentation of the project IRA/89/029. J. Atefi (Karaj, 1994).
Problems in walnut propagation and hot callusing techniques. D. Avanzato (Karaj, 1994).
Seminar on walnut project IRA/89/029 for the cooperative of Tuysarkan. J. Atefi (Hamedan, 1994).
Main propagation techniques applied to walnuts. D. Avanzato (Hamedan, 1994).
Hypocotyl propagation technique applied to walnuts. D. Frutos (Karaj, 1995).
Grafting and vegetative propagation for fruits. D. Avanzato (Karaj, 1995).
Theory and practice of walnut genetic improvement. E. Germain (Sharout, 1996).
What strategy to develop walnut cultivation in Kerman? E. Germain (Kerman, 1996).
Quantity Item Cost
$US
1 000 Mist nozzles 1 800
150 Field tools 2 400
3 pH meters 1 100
3 Hygrometers 1 130
6 Hot callus units 12 183
110 Rootstock and grafted plants 2 000
1 Computer data logger 1 800
1 Video camera 1 559
1 Nut drying machine 6 172
1 Generator 987
1 Hull nut remover 1 779
1 Personal computer 1 753
1 Printer 1 630
A4.1 CONSULTANCY REPORTS
Compte-rendu de la mission en Iran. E. Germain, 1992.
Report on hot callusing grafting. D. Avanzato, 1994.
Report on patch budding technique. D. Avanzato, 1994.
Report on hypocotyl grafting technique. D. Frutos, 1995.
Report on hot callusing grafting and patch budding techniques. D. Avanzato, 1995.
Walnut genotype consultancy. E. Germain, 1996.
Walnut plantation programme. D. Avanzato, 1996.
A4.2 CONFERENCE PAPERS
Evaluation of walnut promising clones. Proceedings of XXIV International Congress. Kyoto (Japan). J. Atefi, 1994.
Comparison of hypocotyl and hot callus cable graft with traditional grafting methods. Proceedings of XXIV International Congress. Kyoto (Japan). J. Atefi, M. Mostafavi, 1994.
Study on phenological and pomological characters in walnut promising clones in Iran. III International Walnut Congress, Alcoba�a (Portugal). Acta Horticulturae. J. Atefi, 1995.
Comparison of hypocotyl and hot callusing grafting systems to traditional grafting methods. III International Walnut Congress, Alcoba�a (Portugal). Acta Horticulturae. J. Atefi, 1995.
The hot callusing system directly applied in the field. III International Walnut Congress, Alcoba�a (Portugal). Acta Horticulturae. D. Avanzato, J. Atefi, 1996.
The promising genotype of walnut. Proceedings of First Horticultural Science Congress of Iran. J. Atefi, 1996.
Comparison of different grafting methods in walnuts. Proceedings of the First Horticultural Science Congress in Iran. J. Atefi, 1996.
