We are currently working to improve this portal.
Over the next few months, we will be fixing errors, improving readability of
articles and updating information. We are always glad to receive your
suggestions for improvements or comments on the portal:
Sections > Latest issue > No.150
Germplasm collections, eco-geography and climate match modelling to southern Australia for Dorycnium species (Canary clovers)
This study aimed to assess the current genetic resources of Dorycnium and, using an ecogeographical analysis, to determine the key ecological factors that might influence their potential adaptation to agricultural regions of southern Australia. Current Dorycnium genetic resources in Australia and New Zealand were surveyed and locations of herbarium and germplasm collections collated. The number of accessions of Dorycnium is very limited, reflecting lack of systematic collection of diversity for plant breeding. Currently, only 58 non-duplicated accessions of 4 species of Dorycnium are held in genetic resource centres in Australia. Passport data for Dorycnium entries in genebanks is scarce, and limited site description information is available from herbarium collections, providing little ecological information related to climate and soil requirements. Climate comparisons between the native distribution of Dorycnium species and Australia were made using spatial aridity data and CLIMEX climate match modelling. This revealed that Dorycniumrectum and D. hirsutum originate from regions with climatic conditions most similar to the temperate pasture zone in southern Australia. Some D. pentaphyllum germplasm was equally correlated, but D. graecum was poorly matched. The wide distribution of D. rectum, D. hirsutum and D. pentaphyllum across the Mediterranean basin suggests that significant genetic diversity might be available in these species that may not be represented in current collections. Targeted collections in Spain, Italy, Greece and Sardinia (Italy) at sites analogous to intended production environments in southern Australia are likely to introduce germplasm better adapt
Genetic variations of gliadin and high-molecular-weight glutenin subunits in diploid wheats
The genetic variations of gliadin and high molecular weight glutenin subunits (HMW-GS) in 113 accessions of diploid wheats, including 30 Triticum monococcum subsp. boeoticum, 41 T.monococcum subsp. monococcum and 42 T.urartu accessions, were identified by A-PAGE and SDS-PAGE. A high level of gliadin variation was found in diploid wheats. The genetic similarity based on gliadin in diploid wheats ranged from 0.100 to 0.960, with a mean of 0.442. Clustering analysis indicated that diploid wheats could be clustered into two major groups. In HMW-GS analysis, 7 1Ax and 5 1Ay subunits were found in 113 accessions of diploid wheat accessions, resulting in 20 HMW-GS combinations. The results indicated that it was reasonable to classify diploid wheat into two species (i.e. T.monococcum and T.urartu) rather than three species (i.e. T. boeoticum, T. monococcumand T.urartu). This is the first report of the HMW-GS variation types in the whole series of diploid wheats, and it is also the first investigation of thespecies relationships based on gliadin and glutenin subunit genetic variation in diploid wheats.
Canavaliacathartica of the south-west coast of India—A neglected wild legume
Canavalia cathartica is widely distributed in marginal and neglected biomes, including coastal sand dunes and mangroves of the south-west coast of India. Seeds of germplasm from various sources were screened for physicochemical features, essential amino acids and fatty acid profiles. Seeds of the sand dune and mangrove germplasm are a rich source of protein and essential amino acids, and comparable to rice, soybean and whole-egg protein. Mangrove germplasm is rich in polyunsaturated fatty acids and an essential fatty acid, linoleic acid. Antinutritional components and traditional knowledge of the gene pool of C. cathartica are discussed. The potential of wild ecotypesof C. cathartica is undoubted, warranting conservation and exploitation for nutritional, agricultural and ecosystem restoration purposes.
Morphological characterization of some Calamus species of north-east India
Rattans, often described as ‘green gold’, supply the basic raw material for furniture and cottage industries. North-eastern India harbours four genera of rattan: Calamus, Daemonorops, Plectocomia and Zalacca. This preliminary investigation characterized 15 rattan accessions of three commercially important genera (Calamus, Plectocomia and Daemonorops), based on 50 morphological characteristics, to provide a better basis for management. UPGMA cluster analysis and principal component analysis (PCA) revealed interspecific variation in the Calamus species and separate identities for Plectocomia assamica and Daemonorops jenkinsianus. In the PCA, 30.63% of the total variability in the first PC was contributed by leaf, plant and fruit characteristics, and 18.05% of the total variability in the second PC was contributed by spine, leaf and some plant characteristics. Based on PCA, 24 morphological traits were identified as minimum descriptors for rapid characterization of rattan germplasm.
Comparative study of indigenous Vigna vexillata (L.) A. Rich. accessions from different latitudes in Indonesia and Australia
A comparative study was conducted of the growth and development of 12 wild accessions of Vigna vexillata from a range of locations from eastern Indonesia to south-eastern Australia. In anticipation that accessions from different latitudes may exhibit differential adaptive photoperiodic response, the plants were exposed to a range of extended photoperiods during their growth. There was significant variation among the accessions for a wide range of traits, although differences in phenology were relatively smaller than those in vegetative biomass and seed and tuber yield. Accessions that produced more vegetative biomass tended to produce more tuber biomass but smaller seed yields. While average biomass production was similar between the Indonesian and Australian accessions, the former tended to produce less seed and smaller tuber biomass. There were no consistent relations between phenology and latitude of provenance. Nor were there any apparent relations between latitude and biomass or latitude and seed yield. However, both the tuber dry weight and the tuber harvest index were progressively greater in accessions from higher latitudes. There were no apparent effects of extended day length on phenology. However, longer days tended to promote vegetative development and reduce partitioning to seeds and tubers, consistent with short-day photoperiodic response. It is suggested that flowering was unaffected by photoperiod treatments because the plants were induced to flower by the short late-winter day-lengths before the treatments were applied. Consistent with this explanation, all plants in all treatments flowered and set pods quickly in all treatments.
ISSR analysis of genetic diversity and relationships among sweet potato (Ipomoea batatas) landraces in China
To analyse the genetic diversity and relationships among Chinese sweet potato landraces and cultivars in China, one hundred landraces from six geographical regions of China and eight cultivars were assessed using inter-simple sequence repeat (ISSR) markers. Fourteen ISSR primers generated 239 polymorphic bands with an average of 17 polymorphic bands per primer. A high average genetic distance and wide variation range were found among Chinese landraces, which were also distantly related to the cultivars with an average genetic distance of 0.6428 (range 0.2591 to 1.6428). The UPGMA dendrogram showed the same genetic relationship among the cultivars in agreement with their known origin and the very wide genetic diversity of the Chinese landraces. The cluster analysis classified the materials into two groups: a major and a minor group. The minor group comprised 14 landraces collected mainly in Guangdong and Fujian, and two cultivars (cv. Nancy Hall and cv. Xu78-1) that are distantly related to each other. The major group consisted of the other 92 accessions. These results indicate that the Chinese sweet potato landraces not only exhibit a high level of genetic diversity but also have a different genetic background from cultivars in China.
Descriptors for Date palm (Phoenix dactylifera L.) characterization and evaluation in genebanks
Until recently, there has been no set of model descriptors for date palm (Phoenixdactylifera L.). We propose here a system of descriptors for date palm to meet the needs of genebanks, insitu and ex situ conservation activities, and as an aid in diversity studies. Multi-score and bi-state systems are used to express the date palm traits. We have compiled standard passport data (17 parameters); details of eco-geography (13 parameters); ethno-botany (15 parameters); management (18 parameters); characterization (58 vegetation parameters, 27 fruit parameters, 22 seed parameters, 41 inflorescence parameters, 4 molecular marker parameters, 5 cytological parameters and 24 biochemical parameters); and evaluation activities (66 biotic stress parameters and 13 abiotic stress parameters). These attributes were derived from 1275 samples representing 55 varieties cultivated in Egypt. Trait data were collected both from trees growing in their natural habitats as well as from trees growing ex situ on the farm of the Central Laboratory of Date Palm Research and Development (CLDPRD) genebank. The proposed date palm descriptors provide a standardized information set for all characterization and evaluation activities for date palm genebanks.
Infraspecific diversity in Cuban agroecosystems in support of sustainability
The small amount or lack of genetic variation between and within cultivars (genetic uniformity), gives rise to high risk in agricultural systems (genetic vulnerability). Therefore every effort is made to minimize the magnitude of their effect. One way to avoid genetic uniformity in production systems, and therefore the increase in vulnerabiltiy, is to use a mixture of cultivars within each crop, which provides stability in production. Another aspect to the problem is the need to include in the different production systems traditional cultivars with a high degree of genetic heterogeneity; such cultivars are typical of small, scale peasant systems, and form the basis of their production. In conventional production systems the presence of high infraspecific variability is not very common, although it gives rise to better results in traditional systems and in other non-conventional initiatives that favour diversification and diversity within crops. Based on information from the database of the Cuban National Information Sharing Mechanism on plant genetic resources for food and agriculture (PGRFA) for the period 1995–2003, and also from the data on several cultivated species in small-holdings in Cuba derived from the activities of the IPGRI-GTZ multinational project, we discuss the projects developed in the country, the limitations in material for diversification and the increase in crop diversity, the politics and market incentives for diversification, staff training and the priorities and requirements needed to bring about these strategies, as well as related national, regional and international opportunities.
Survey of cultivated and wild edible plant species used in the Department of Chocó, Colombia
The Department of Chocó (Colombia) is an area with a great diversity of plants, many of which are used for food purposes. A survey (1999–2002) made for cultivated and wild edible plants in some river basins and markets of the Department found 75 species (33 cultivated, 35 wild or naturalized, and 7 both cultivated and naturalized or adventitious) from 25 botanical families. Results are presented on the features specific to the Chocó, and on the importance and value of each species. Most species, either cultivated or wild, are destined for local markets, although some cash crops exist (mainly banana and cocoa). Several species, like borojó (Borojoa patinoi), are endemic to the Chocó. Also, some types of rice and maize able to resist seawater intrusions are of particular interest. It is remarkable that a significant number of the plants used are wild or naturalized, with many plants from other regions seemingly adapted well to the natural environment of the Chocó. In general, a great diversity of types exists within each species, and, in the case of cultivated plants, there are few improved varieties. In conclusion, in the Chocó there is a great diversity of plants used for food purposes and a considerable associated ethnobotanical knowledge, which has mostly remained neglected and unknown to the rest of the world.
The European Poa Database (EPDB) of the European Cooperative Programme for Crop Genetic Resources Networks (ECP/GR) is maintained by IPK Genebank, External Branch “North” at Malchow/Poel, Germany. Passport data, based on the FAO/IPGRI EURISCO descriptor list, document about 5 000 accessions. 36 species originating from 53 countries are represented by advanced and primitive cultivars (728), breeding material (122), landraces (1 310), ecotypes (112), weedy types (42) and wild material (1 010). The accessions are conserved in genebanks in 16 countries throughout Europe, and both seed and information can be requested direct from the holding institutes. EPDB uses the relational database management system (DBMS) Oracle and is searchable on-line at http://poa.ipk-gatersleben.de. Additionally, the dataset can be downloaded as a Microsoft Excel file.
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.