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English
Characterization of germplasm according to environmental conditions at the collecting site using GIS—two case studies from Brazil
The limited use of large germplasm collections has been attributed to limited information regarding the germplasm conserved. Information about environmental conditions of germplasm collecting sites may be important additional data, because those conditions are normally associated with the patterns of genetic variability. Through the use of geographic information systems (GIS), overlaying environmental maps with geographic data of the accession collection points, it is possible to estimate these environmental conditions. This constitutes an uncommon type of characterization: ecological descriptors. In this paper we present two examples of the use of this methodology: (1) the definition of an ecogeographic stratification for the landraces of the Brazilian Cassava Collection for the development of the Brazilian Core Collection of Cassava; (2) the identification of rice landraces collected in areas with specific environmental conditions or stresses, to be used as sources for breeding. To develop the Core Collection of Cassava, landraces were stratified into ecogeographic regions of origin. These regions were obtained through the combination of different maps of vegetation and climate of Brazil (scales from 1:5 to 1:2 million). For the rice study, maps of vegetation, climate, and zoning of Brazil were used (scales from 1:5 to 1:2 million). Rice accessions collected in regions with cooler thermic regimes, soil salinity, very low fertility in the Cerrados, and semi-arid regions, were identified. The characterization of germplasm according to origin through GIS is a tool that may help in understanding and accessing the genetic variability of large germplasm collections.

By M. Lobo Burle  C. M. Torres Cordeiro  L. A. Martins Palhares de Melo  R. de Belem das Neves Alves  Tabaré Abadie  J.R. Fonseca  

published on No.135, in English
Page 1 to 11

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English
Collecting and morphological evaluation of 'njavara', a traditional medicinal rice (Oryza sativa L.), in Kerala , India
Oryza sativa cv ‘njavara’ is a medicinal rice traditionally used in ayurveda, the most ancient health care system in India . Its cultivation is confined to Kerala state, India and its germplasm is largely undocumented. Twenty samples of ‘njavara’ seeds were obtained from 15 sites belonging to eight districts in Kerala from May 2000 to March 2001. The collections were subjected to a preliminary evaluation using six quantitative and 15 qualitative characters. Two glume colours, black and golden yellow, were evident among the collections. The accession means for the quantitative traits examined varied significantly (p<0.05) among the collections, and nine out of 15 qualitative traits also showed variations. To some extent, it was possible to group the germplasm into three morphotypes: (i) tall (culm length=102.9 ± 13.09 cm) with golden yellow glume (tall yellow); dwarf (culm length=76.9 ± 9.29 cm) with golden yellow glume (dwarf yellow) and dwarf (culm length=76.18 ± 10.48 cm) with black glume (dwarf black). Results of this preliminary exploratory analysis demonstrate that ‘njavara’ is genetically highly diverse and is a composite of distinct morphotypes, thus pointing to the need for biochemical evaluation.

By Sreejayan  V. Raghava Kumar  G. Thomas  

published on No.135, in English
Page 12 to 17

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English
The world banana heritage conserved in Belgium for the benefit of small-scale farmers in the Tropics
The banana (Musa spp.) world collection at the INIBAP Transit Centre consists of 1144 accessions, representing a wide range of natural and improved banana varieties, and wild forms. Accessions are stored in tissue culture form under slow growth conditions. Recently, cryopreservation techniques have been developed and efforts are underway to preserve the entire collection in liquid nitrogen. Germplasm held by INIBAP is freely available for use and the distribution of healthy samples, especially of improved varieties for evaluation, is an important and increasing activity of the genebank. In conjunction with NARS, breeding programmes and researchers, INIBAP coordinates the International Musa Testing Programme (IMTP). This programme allows natural and improved germplasm, deposited in the world collection, to be tested under varying environmental conditions and different pathogen pressures in a large number of countries worldwide. This activity has resulted in the identification of several more productive and disease resistant varieties suitable for direct use by farmers and small-scale producers. These superior varieties are starting to be incorporated into the existing agricultural systems in a number of countries. In Cuba , Nicaragua and Tanzania , for example, these varieties are having a positive impact on food security, as well as contributing to improved food quality and a better income for small-scale farmers.

By E.A. Frison  S. Sharrock  I. Van den houwe  P. Lepoivre  R. Swennen  

published on No.135, in English
Page 18 to 23

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English
Ethnotaxonomy of Dioscorea among the Kattunaikka people of Wayanad District, Kerala, India
Dioscorea is a tuberous plant genus that provides nutritious food for farming families in several tropical and subtropical regions of the world. Wild Dioscorea species are still a major source of food for forest communities in many tribal and rural areas in India . Taxonomic distinctions in this genus are often difficult to make because of their high morphological variation. Here we report how the indigenous Kattunaikka people of Wayanad district in Kerala classify and name plants in the genus Dioscorea. This may help authorities to assess the contributions and needs of indigenous people who manage and use wild relatives and traditional cultivated varieties of Dioscorea, and to develop methods for rewarding them under the Plant Varieties and Farmer’s Rights Act 2000 of India . Researchers have reported 11 species and four varieties in Dioscorea so far from Wayanad. The present study shows that the Kattunaikka tribe can distinguish 21 taxa of which they consume 19. The local classification is based on morphology and function or appearance when processed for consumption, while the botanical classification is based entirely on morphological characters. The key characters adopted by the indigenous community for classifying members of Dioscorea are usually the eating quality and morphology of the underground tuber.

By V. Balakrishnan  M.K. Ratheesh Narayanan  N. Anil Kumar  

published on No.135, in English
Page 24 to 32

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English
Genetic diversity, population structure and mating system in endemic Hedysarum carnosum Desf. (Fabaceae)
Hedysarum carnosum Desf. has become increasingly rare across parts of its range in south-eastern Algeria and southern Tunisia . We used enzyme electrophoresis to characterize genetic diversity and population structure in 10 populations of this species. On average 82% of the loci were polymorphic, the number of alleles per locus was 2.3 and the observed and expected heterozygosities were 0.239 and 0.302, respectively. There was evidence for genetic differentiation between populations ( q = 0.23) caused by habitat fragmentation from human land use, which reduced population size and restricted gene flow. Estimates of outcrossing rate and multiple paternity at different hierarchical levels in a population of H. carnosum were made using four allozyme loci. The multilocus (t m) and average single locus (t s) outcrossing rates were 0.962 and 0.930, respectively, indicating a predominantly outbreeding mating system. The correlation of outcrossed paternity (r p) was significant within pods (0.325) and within inflorescence (0.192). The understanding of the organisation of genetic diversity and mating system of H. carnosum provided by our results will help in the conservation of its genetic resources.

By M. Louati  A. Chriki  I. Louati-Namouchi  

published on No.135, in English
Page 33 to 39

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English
Diversity of Saccharum germplasm in Kerala, India
Some of the major river basins in the state of Kerala , India were surveyed forthe collection of Saccharum germplasmduring December 1999. Saccharum spontaneum was found to be extensively distributed throughout the course of the Bharathapuzha river, which is the second longest river in the state. The species has established itself as a major plant element with a massive presence along the riverbanks and riverbeds, facilitated by profuse flowering, seed set and optimal conditions for the dispersal and germination of the seeds. Other river basins in the state showed relatively less presence of S. spontaneum. The variability for plant characters across the different river zones was found to be essentially the same. Erianthus arundinaceus was present along most of the rivers, though variability and distribution was found to be limited. A total of 54 S. spontaneum and 17 E. arundinaceus clones were collected from the different river zones of the state.

By N.V. Nair  K. G. Somarajan  

published on No.135, in English
Page 40 to 43

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English
Fungi associated with seeds of Coffea arabica
Thirty-four samples of dried coffee seeds collected from farmers in the western highlands of Cameroon were tested for the presence of fungi, following the blotter method commonly used for seed health testing. The samples were infected with two pathogens of coffee (Fusarium moniliforme and F. solani). Many other fungi were also recorded (Aspergillus flavus, A. niger , A. fumigatus, A. ochraceus, A. versicolor, Beauveria bassiana, Cladosporium cladosporioides, Curvularia lunata, F. pallidoroseum,
Macrophomina phaseolina, Penicillium atramentosum, P. aurantiogriseum and P. chrysogenum). The pathogen of coffee berry disease, Colletotrichum kahawae, was not found and it is concluded that this fungus earlier reported in freshly harvested coffee seeds does not survive after drying. Movement of dried coffee seeds is probably very safe in respect to this pathogen.

By A. Tagne  S.B. Mathur  

published on No.135, in English
Page 44 to 46

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English
Description of variation in the Indian accessions of the medicinal plant Centella asiatica (L.) Urban
A germplasm collection, comprising 16 accessions of Centella asiaticafrom different locations in India was characterized using multivariate approaches. The 16 accessions were found to harbour considerable variation and dispersed into 9 clusters/classes on the basis of principal component and canonical variate analyses of 18 quantitative traits. The number of accessions in the classes varied from 1 to 4 with 5 classes having single accession each. A similar distinction could be seen in the dendrogram constructed from D 2 values which demarcated clusters IX and VII from the rest of the accessions and from each other. Perceptible differences could also be discerned in the colour, shape and size of vegetative and floral parts that have been depicted using metroglyph representation. The present study showed the existence of two distinct morphotypes in C. asiatica. It was hypothesized that the plant’s ability to adapt successfully to a wide range of ecological conditions is the main factor underlying the extent of its genetic variability.

By S. Kumar  S. Mathur  Srikant Sharma  

published on No.135, in English
Page 47 to 52

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English
Romanian wheat (Triticum aestivum L.) landraces characterized by seed storage-protein electrophoresis
Forty Romanian wheat landraces, stored in the active collection of the Suceava Genebank, were characterized by means of glutenin analyses. Their HMW-GS patterns, homogeneity and heterogeneity, and Glu-score were determined and characterized by SDS-PAGE. Seed storage protein patterns analysed in this study indicate a relatively high level of protein heterogeneity. Only five of the accessions analysed were found to be homogeneous: 87.5% were heterogeneous, with from 2 to 14 different protein patterns. In total 202 different protein phenotypes (lines, biotypes) were detected. Together 13 HMW-GS alleles were detected at all three Glu-1 loci. The most frequent, at relevant loci, were alleles null, 7+9 and 5+10. More than 10% of protein phenotypes reached a maximal value Glu-score.

By M. Popa  E. Gregova  J. Kraic  

published on No.135, in English
Page 53 to 58

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English
Propagation of a threatened medicinal herb Aconitum atrox (Bruhl) Muk. through tuber segments
A vegetative propagation study of Aconitum atrox (Bruhl) Muk. using tuber segments was carried out at lower elevation (1900 m asl) than its natural habitat (2800–4500 m in the Garhwal Himalaya, India). Apical tuber segments containing well-defined winter dormant buds produced a single shoot, whereas sub-apical, middle and basal segments lacking shoot buds exhibited the tendency to produce more than one shoot, however, all tuber segments could produce more than one tuber and several roots. Pre-soaking of the tuber segments for 48 h in 10 mg l –1 aqueous solutions of gibberrellic acid (GA 3), indole butyric acid (IBA) and kinetin was observed to promote tuber development. 4.0±2.0 young tubers were produced from apical segments pre-treated in a combination of 10 mg l –1 aqueous solutions of three growth regulators. In the same treatment 10±3.0 young tubers were produced from sub-apical segments. Also, in the combination of three growth regulators the length of young tubers from apical segments was 12.9±3.0 cm. Combining 10 mg l –1 concentrations of GA 3 and kinetin enhanced tuber development from basal segments. Apical tuber segments produced healthy sprouts and tubers compared with other segments. The regeneration potential of tuber segments was recorded to decrease gradually from apical to sub-apical, middle and basal segments. Tuber segments of ~2.5 cm length were found suitable for propagation, whereas smaller ones produced fewer and weaker sprouts.

By P. Prasad  C. P. Kuniyal  C. Rajsekaran  S.K. Bhadula  

published on No.135, in English
Page 59 to 62

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Musa spp. germplasm maintained at the INIBAP Transit Centre is conserved in vitro in the form of proliferating shoot tips (C. Boursnell/IPGRI). Van den houwe et al. discuss the importance of this world collection of banana, pp. 18 –23. 


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This newsletter, published under the joint auspices of the Bioversity International (Bioversity) and the Food and Agriculture Organization (FAO), features articles and reviews of developments in plant genetic resources, book reviews, news and notes on Bioversity activities.

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