Preliminary results on the production of heart of coconut in Vanuatu. Effect of the planting density on the yield

This article presents the results of a field experiment on the production of heart of coconut (HOC) in Santo Island, Vanuatu. It demonstrated that the production of HOC is possible under the conditions of northern Vanuatu without irrigation and with low inputs. Only sodium chloride was applied as a fertiliser and the use of scrap copra sacks as a mulch was proved particularly efficient to reduce the weeds invasion and to preserve moisture. In this experiments, 3 densities of planting in an equilateral pattern with a spacing of 0.8 m, 1A m and 2.0 m were tested, and the growth parameters of the seedlings and the yield of the final product over a period of 2 years were recorded. It appeared that the higher the density of planting, the lower the weight of each HOC and the higher the yield by area unit. Two years after planting, the yield of HOC was 11.8 MT/hectare (0.8 m spacing), 7.7 MT/hectare (1.4 m) and 6.4 MT/hectare (2.0 m) with an average weight of HOC of 688 g, 1372 g and 2330 g respectively. The market requirement for HOC individual weight must be taken into account to choose the appropriate spacing and duration of cultivation. A strong relation between the stem girth and the HOC weight that can be described in the form of an allometric equation makes easy to estimate at any time the potential yield of HOC by measuring the stem girth of the whole palm. (Résumé d'auteur

New observations on the resistance of coconut cultivars to tropical cyclones in Vanuatu

The resistance of coconut palms to violent winds was observed at the Saraoutou research station as cyclone Dani passed over tile island of Santo in Vanuatu in January 1999. Mortality caused by felling or uprooting was recorded on 13 Dwarf varieties, 10 Tall varieties and 28 Dwarf x Tall hybrids. The Dwarf palms were generally more susceptible than the 'fall palms and hybrids, but substantial differences were also found between varieties in the same group. At 15 years old, the Tacunan Green Dwarf originating from the Philippines proved to be the most resistant Dwarf with 0% of felled palms compared to 100% of felled palms for the most susceptible, the Malayan Yellow Dwarf. Of the Tall palms, the Vanuatu Tall proved to be the most resistant with 2% of felled palms. The varieties originating from the South Pacific or the Philippines also displayed good resistance compared to varieties from Papua New Guinea. Of the hybrids, the Malayan Red Dwarf x Rennell Tall displayed the least resistance. The effect of different factors (morphological characteristics, age) on susceptibility to violent winds is discussed

TropGeneDB, the multi-tropical crop information system updated and extended

TropGeneDB (http://tropgenedb.cirad.fr) was created to store genetic, molecular and phenotypic data on tropical crop species. The most common data stored in TropGeneDB are molecular markers, quantitative trait loci, genetic and physical maps, genetic diversity, phenotypic diversity studies and information on genetic resources (geographic origin, parentage, collection). TropGeneDB is organized on a crop basis with currently nine public modules (banana, cocoa, coconut, coffee, cotton, oil palm, rice, rubber tree, sugarcane). Crop-specific Web consultation interfaces have been designed to allow quick consultations and personalized complex queries. TropGeneDB is a component of the South Green Bioinformatics Platform (http://southgreen.cirad.fr/). (Résumé d'auteur

Towards a bioinformatics platform for the Musa research community : [Abstract W076]

Current experiments in genomics produce a large amount of data that needs to be organized into databases and broadly accessible. Like other species, the Musa genomics community would benefit from centralized and innovative ways to study its genome. Over the past years, genetic and genomic data (e.g. BAC, EST, Markers) have been generated and stored in databases. Several pipelines of analyses were implemented for gene, transposable element, and expression data analyses, and for comparative genomics such as ortholog predictions via a phylogenomic approach (GreenPhyl). Web tools have been developed or implemented to facilitate access to data, such as genetic makers (TropGeneDB), genetic maps (CMap), a physical Map (GBrowse), and Expressed sequence Tags (ESTtik) gene/TE predictions, and to allow online manual genome annotation (GnpAnnot). The number of tools may continue to grow, in particular with the near release of the Musa genome sequence, and the increase of Next-Generation Sequencing (NGS) facilities. The GMGC website (http://www.musagenomics.org) is a place where data can be shared, and where databases and tools can be listed in an homogeneous way to serve the Musa genomics community. It is intended to provide the researchers interested in Musa with a common set of resources in order to work more efficiently and effectively. (Texte intégral

Collection and ex situ conservation of coffee landraces in Ethiopia. The example of Harerge

The south-western highlands of Ethiopia are recognized as the primary centre of diversity of Coffea arabica L. However, relatively little is known about the situation of coffee genetic resources collected and conserved ex situ within Ethiopia. In 2005, we started compiling an electronic database of coffee genetic resources conserved at the Jimma Agricultural Research Centre (JARC). Since 1967, 48 campaigns of collections have been undertaken by the Ethiopian research organization, with the main objectives to capture the genetic diversity and search for genotypes tolerant to coffee berry disease. To date (July 2006), 4731 distinct accessions are presently conserved and evaluated by JARC in field gene-banks at Jimma-Melko centre and at 9 sub-centres located in the main coffee growing areas. In Harerge, a coffee zone in the East of the country, coffee is produced in highly diversified farming systems adapted to different ecological niches. Harerge fetches premium prices in the world market but this resource is under threat of erosion. Out of 30 Harerge woredas (districts) with significant coffee production, JARC has collected coffee landraces in 20 woredas. In all, a total number of 1952 Harerge accessions are conserved in JARC field gene-banks at the Jimma-Melko centre and Mechara sub-centre. They are assessed regularly for yield, disease tolerance, and quality. (Résumé d'auteur