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Working Groups
1. Purity
Working Group Revision of purity definitions, particularly concerning wings on seeds of Abies, and Pinus species /1: Leader: D.G.W. Edwards; Members: G. Johnson Z. Prochazkova
2. Germination
Working Group Tropical tree seed germination /2: Leader: H. Pritchard; Members: K. Thomsen
Working Group Stratification of pine seeds /3: Leader: G. Johnson;
Working Group Comparative tests of Abies germination/5: Leader: G. Johnson; Members: D.G.W. Edwards, Z. Prochazkova
3. Tetrazolium
Working Group Harmonisation Table 6. Tetrazolium tests with Table 2 Sampling/5: Leader: Z. Prochazkova;
Working Group Comparative tests/6: Leader: Z. Prochazkova; Members: E. Foffova
4. Workshops
Working Group Tree seed testing workshop /8: Leader: Z. Prochazkova; Members: E. Foffova
Publications
Working Group Revision of the publication 'Microorganisms associated with tree seeds: World Checklist 1990 /9: Leader: R. Mittal;
Working Group Revision of the ISTA Tree and Shrub Seed Handbook /9: Leader: Zdenka Prochazkova; Members: Daniel Baskaran, Fabio Gorian, Elena Foffova, Peter Gosling, Dave Kolotelo. Beti Piotto, Hugh Pritchard, Dale Simpson, Heidi Rosok Bye
Working Group Multi-lingual glossary of common plant names for forest tree and shrub species /11: Leader: Zdenka Prochazkova; Members: Daniel Baskaran, Fabio Gorian, Elena Foffova, Beti Piotto, Hugh Pritchard
Activity Report
WG 1: Revision of purity definitions, particularly concerning wings on seeds of Abies, and Pinus species
A proposal to revise the ISTA Rules is in progress.
WG 2: Tropical tree seed germination, especially palms - to develop appropriate germination tests on ca 25 species
Palms
Seed lots of 16 palm species from 13 genera have been investigated for their germination competence at 30°C (12 h photoperiod) on agar-water substrate. Seed lots were sown soon after receipt. Germination levels for 14 species varied from 35 %, in Trachycarpus latisectus, to 100 %, in Adonidia merrillii. Mean times for germination (MTG) were relatively short for these species, as follows: Adonidia merrillii (22 d), Caryota mitis (25 d), Ceroxylon alpinum (39 d), Ceroxylon quindiuense (43 d), Chuniophoenix hainanensis (27 d), Chuniophoenix nana (35 d), Dypsis onilahensis (43 d), Hyphaene coriacea (17 d), Licuala ramsayi (37 d), Livistona muelleri (18 d), Ravenea glauca (20 d), Ravenea rivularis (12 d), Sabal maritima (20 d) and Trachycarpus latisectus (30 d). MTGs were much longer for the other two species: Copernica glabrescens (81 d) and Cyrtostachys renda (120 d). However, it was noticeable that these seed lots had low seed germination (22 and 18 % respectively).
Reference: PRITCHARD HW, WOOD CB, HODGES S, VAUTIER HJ (2004). 100-seed test for desiccation tolerance and germination: a case study on eight tropical palm species. Seed Science and Technology (in press)
Other species
Prunus africana, from the moist highlands of sub-Saharan Africa, is subject to great exploitation because its bark is used in the treatment of prostate-related diseases. A better understanding of the biology of its seed could help the sustainable use of this tree. Fifty percent of fresh seeds (47 % moisture content) from mature purple fruits harvested in Kenya germinated after 10 days incubation at 25 °C. The germination rate was linearly related to constant temperature, giving a prediction for the minimum temperature for germination at c. 0.6 °C. All seeds germinated at 5 °C during 4 months fully hydrated storage. P. africana seed is, thus, neither dormant nor chilling sensitive. Such a low temperature germination response seems consistent with the species distribution at altitude.
Reference: SACANDÉ M, PRITCHARD HW, DUDLEY AE (2004). Germination and storage characteristics of Prunus africana seeds. New Forests (in press).
This work was supported by Kew colleagues Chris Wood, Simon Hodges, Moctar Sacandé, Anna Dudley, Helen Vautier and Frances Briscoe, with Wen Bin (Xishuangbanna, P.R. China), Laurent Guy Rakotondranony (SNGF, Madagascar) and William Omondi (KEFRI, Kenya).
WG 3: Stratification of pine seeds (Pinus elliottii, P. palustris and P. taeda)
Double germination tests (with and without prechilling) for Pinus elliottii, P. palustris, and P. taeda have been introduced to the ISTA Rules.
On the request (Minutes of the ISTA EOM 2003) clarification of the expression "double tests" has been proposed.
Wg 4: Comparative tests of Abies germination
Preparation of the test is in progress, and a proposed working plan has been circulated to members of the FTS Committee. Depending on availability of seed lots, the test is planned to start in early 2004.
WG 5: Harmonisation Table 6 Tetrazolium test with Table 2 Sampling
No progress to date. The draft proposals will be prepared before May 2004.
WG 6: Comparative tests
No progress to date. The activity will be postpone to the 2004-2007 period.
WG 7: Tree seed testing workshop
The FTS Committee Workshop took place in Prague, Czech Republic (October 20-23) followed by two alternative post-meeting tours (1-day trip to Tree Seed Plant and 3-days trip to CZDL02, SKDL02 and Slovak Tree Seed Plant).
WG 8: Revision of the publication 'Microorganisms associated with tree seeds: World Checklist 1990
No reply from the activity leader yet.
WG 9: Revision of the ISTA Tree and Shrub Seed Handbook
No progress since last year. This activity has been postponed to the 2004-2007 period.
WG 10: Multi-lingual glossary of common plant names for forest tree and shrub species
No progress since last year, and the activity has been postponed for the 2004-2007 period.
Future Aims
1. Revision of purity definitions, particularly concerning wings on seeds of Abies, Pseudotsuga, and Pinus species
A proposal will be made to separate these genera in distinctive pure seed definitions. Other proposals will be made concerning Sequoiadendron, Taxodium, and Taxus.
2. Comparative tests of Abies germination
The test will start early in 2004.
3. Comparative tests
A questionnaire will be sent to all ISTA laboratories testing forest tree seeds in March 2004.
4. Proficiency testing
Based on a discussion on Proficiency tests of forest tree and shrub seeds at the FTS Committee members meeting during the FTS Workshop in Prague, a proposal of the ISTA "Referee Samples Preparation Instructions For Referee Test Leaders" for forest tree seeds will be made before May 2004.
5. Tree seed testing workshops
Based on the discussion in the FTS Committee meeting in Prague, the tetrazolium workshop of forest tree and shrub seeds will be organised for the 2004-2007 period.
6. Revision of the ISTA Tree and Shrub Seed Handbook
A questionnaire will be sent to laboratories in March 2004.
7. Multi-lingual glossary of common plant names for forest tree and shrub species
Revival of this activity is planned prior to May 2004.
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Seed Science and Technology
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