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 Main subject - july/aug 2007
continuation: Join event by ABRATES and ISTA successful as expected
An overview of the seed symposium
Julio Marcos Filho
jmarcos@esalq.usp.br
Brazil is a tropical country whose different regions do not exhibit extreme climatic variations and allow excellent environmental conditions for the production of grain, vegetable, fruits, forage, and woody crops of tropical to temperate origin.
The strategic importance of the Brazilian agricultural sector has been documented over time. The contribution of the whole chain of agribusiness to the Brazilian gross domestic product (GDP) has been about 26% to 32% in the last years, but it can be higher.
Dr. Silmar Peske, president of the event
The country is one of the largest producers of the most important crops in the world and contributes to a significant percentage of the world's total agricultural production. The average productivity of major crops is similar to or greater than the world average and continues to increase in the last decade.
The Brazilian seed industry is well developed and until the middle 1990s, both national and international companies were active and competitive. Recently, there has been a significant increase in mergers of some national companies by international seed companies. Even so, in 2006, the Association of Brazilian Seed Producers had 554 registered members, each representing a seed company. The Brazilian seed market is substantial and consists primarily of grain, vegetable and tropical forage grass crops. It represents 7.5% of the total world seed market in 2005/2006.
Participants of the Symposium
Although this brief presentation of Brazilian Agriculture and its seed industry permits a general view of the strength of these activities, it is also not surprising that Diversity in Seed Technology has been chosen as the central theme of the 2007 ISTA Symposium.
First, the relationships between the word diversity and many Seed Science and technology activities are large and dynamic. They suggest opportunities for differing research approaches such as , seed morphological and genetic variability among different plant genera and species; a broad manifestation of vital processes directly affected by genotype; alternatives for seed-borne disease and insect control; the adoption of different procedures during pre- and post-harvest seed production; factors associated with the production of high quality seeds; the variation of the technology levels in different regions of the world, and many others that clearly illustrate this relationship.
In addition, one of the most important human priorities emphasized around the world is the preservation of biodiversity that is constantly being threatened by our disorganized exploration of natural resources. Biodiversity is not uniformly distributed in different parts of the world regions, being more ample in the tropics. Brazilian natural resources are vast and illustrated by this country's prominent position as a holder of 25% of the world biodiversity. As a consequence, the selection of the theme "diversity in seed technology" could not be more appropriate for this international seed meeting hosted by Brazil.
The Seed Symposium of the 28th ISTA Congress held in Fóz do Iguaçu, in the Paraná State, from May 7 to 9, 2007 with 1092 registered participants representing more than 40 countries was simultaneous to the15th Brazilian Seed Congress.
The theme of the Symposium was developed in six sessions, each with a keynote address presented by the respective Chair and six oral presentations and by 358 submitted papers distributed in two poster sessions following the same topics selected in the oral sessions. Considering the country of origin of the main author of each paper at these meetings, the same trend as displayed in the Symposium held in Budapest/2004, continues to illustrate the significant contributions of Brazilian papers (42.8% of the total), followed by India (15.8%), Argentina (6.6%), Iran (6.4%) and France (2.8%)and others (7.4%). This clearly documents where the volume of active seed research is occuring considering the countries that attended the symposium.
Dr. Julio Marcos Filho, at the moment of his speech
The percentage of papers according to main topics covered at the three preceding symposia held in Pretoria, Angers and Budapest respectively is presented in Table 1. These data permit comparisons and the identification of important shifts in seed research since 1998.
The number of papers has steadily increased, but seed physiology papers continue to be prominent over time. Research in seed testing remains popular with a major emphasis on seed vigor assessment and studies of alternatives to the standard germination test which are closely tied to a seed physiology approach. These trends have not changed since the 23rd ISTA Congress in Buenos Aires, Argentina in 1992. This table also shows variation in the intensity of research in seed production, pathology and drying/storage.
In today's Symposium, the following sessions are supported by oral presentations and poster papers:
1. Diversity within and among seed lots and species - This session included 53 papers, representing 13.5% of the total papers submitted. The majority of the studies focused on procedures for seed identification using morphological characteristics, molecular markers and computer imaging analysis. Of particular note is the increase in number of papers involving seed quality assessment of native plants.
2. Problems associated with the domestication of non-crop species - This area comprised 26 papers (6.7% of total) that primarily examined the requirements for germination of different species, procedures for overcoming seed dormancy and mechanisms of desiccation tolerance. These topics are fundamental to the domestication of native species. The session also included a significant number of papers concerning medicinal and native forests seeds and maintenance of genetic diversity.
3. Diversity in contaminating organisms - Among the 41 (10.5% of total) submitted papers, this session focused almost exclusively on seed-borne diseases. It also considered papers that were quite diverse with respect to species studied. Interestingly, there was a relative decline of papers describing chemical seed treatments and increases in biological control and the use of alternative procedures such as physical (thermotherapy), areas that were relatively well emphasized at the Budapest symposium.
Several papers dealt with methods for detection of microorganisms associated with seeds of different species, including the use of molecular markers and studies of seed health in organic production systems.
4. Seed development, dormancy and germination: physiology and methods - This session included 104 communications (26.6% of total) dealing primarily with studies of maturation, germination, relationship between proteins and seed vigor, procedures to overcome dormancy as well as molecular markers to obtain basic information. Some papers focused on the effects of growth regulators on physiological processes in seeds.
The increase in the number of papers on medicinal plants and forestry seeds was also found in this session and concentrated on desiccation tolerance.
5. Vigor and invigoration - The greatest number of papers (106, 27.1% of total) was submitted to this session. Approximately 50% were directed at different aspects of seed vigor (assessment, relationship with seed performance in the field and during storage, association with deterioration, etc). This concentration of papers confirms the need for a continuing search for assessment procedures to provide standardized information on seed performance ability and emphasizes that stand establishment remains a crucial component of crop production. The same is true for studies on seed storability.
Papers on seed vigor focused on refinements of validated and recognized tests to assess the physiological potential of less studied seeds instead of the development of new proposed vigor tests. In addition, there was an increased use of computer imaging analysis as a resource for studying seed vigor.
In general, papers on seed priming emphasized methodology, the identification of causes and effects of treatment, and the use of efficient procedures to avoid possible reversal effects following drying and storage of conditioned seeds.
6. Seed storage and conservation - This area comprised 61 papers (15.6% of total) that addressed drying methods, factors affecting storability of orthodox and recalcitrant seeds, procedures for the assessment of seed moisture content, seed desiccation tolerance and conservation of genetic resources. There was a significant decrease in the number of papers on fruit and forestry tree seed storage in comparison to previous symposia.
The word diversity can be used again to emphasize the wide range of seed topics covered in this 28th ISTA Congress presented as oral and poster papers that provided an interesting combination of basic and technological approaches in cultivated and native plant seed production. The authors broached differing aspects of seed behavior and provided an overview of issues and problems associated with seed quality components thus offering informative and thought provoking ideas and concepts, new approaches and possibilities to solve important problems found in different regions and countries of the world.
Jitka Koctianek, presenting one of the works that was awarded with the title, "The impact of provenance, season and season differences on the seed longevity of nine Australian native species"
Our deeper knowledge of the germination process and mechanisms of metabolic block that characterize seed dormancy represent critical information guiding the rational use and preservation of natural resources. This fundamental understanding has paved the way for improved uses of native and medicinal plants as a world priority as discussed in the different sessions of this Symposium.
Graduated students and staff of the Federal University of Pelotas at the congress
The significant interest in areas such as cultivar identification and preservation of genetic purity reflect dynamics in plant breeding programs. At the same time, it was possible to determine current and future priorities in seed science and technology research such as:
Post-harvest seed technology;
Seed pathogen biological control;
Use of molecular markers in differing aspects of seed technology;
Problems associated with organic seed production;
Studies on the mechanisms of gene expression in relation to seed germination and vigor;
Relationship of proteins and physiological processes in seeds;
Computer imaging seed analysis as a tool for studies of different aspects of seed technology.
The improvement of testing procedures to assess the physiological component of seed quality and the estimation of seed performance potential in the field and storage are continuing priorities. Other papers focusing on a wide range of less studied species in different regions of the world provide guidance in rational decisions to preserve our natural resources.
The analysis of the papers in this Symposium reveal a broad and consistent information. This evaluation has shown that the papers presented from different regions in the world are conducted by highly qualified scientists capable of maintaining undeniable energy and the desire to present high quality seed research.
The fundamental importance of maintaining active seed research programs persists as a result of continuing developments in plant breeding programs and the unquestionable evolution of crop production technology as a guarantee of providing interesting and useful genes to mankind in a competitive environment.
Therefore, under the biological approach, seeds represent the continuation of life. Under the technological approach, seed is the most efficient way to transfer advances in plant genetics and breeding to farmers. From the perspective of these two view points, the dynamics of seed research is irreversible and will continue to represent significant short and medium term progress as outstanding symbols of diversity.
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