Search for alternate hosts of the coconut Cape Saint Paul Wilt Disease pathogen

Lethal Yellowing disease locally called Cape Saint Paul wilt disease (CSPWD) is the bane of the coconut industry in Ghana and is caused by a phytoplasma. In Ghana, there are areas where the disease has re-infected re-plantings long after decimating all the palms in the area. This brings to the fore the possibility of alternate hosts in the spread of the disease because the pathogen is an obligate parasite. In this work, a number of plants were screened for their host status to the CSPWD pathogen. The presence of phytoplasmas in these plants was tested by polymerase chain reaction analysis using universal phytoplasma primers P1/P7 and CSPWD-specific primers G813/GAKSR. Although Desmodium adscendens tested positive to the CSPWD-specific primers, cloning and sequencing did not confirm it as an alternate host. The identification of alternate hosts will help us to evolve sound control strategies against the spread of the disease. (Résumé d'auteur

Evaluation of some basic traits of a promising coconut hybrid: Sri Lankan green dwarf crossed to Vanuatu tall (sgd x vtt)

The Lethal Yellowing Disease locally referred to as the “Cape St Paul Wilt Disease” is the single most important disease that has devastated several hectares of coconut plantations in Ghana. Two decades of coconut screening for tolerant planting material has identified the Sri LankanGreen Dwarf crossed Vanuatu Tall (SGD x VTT) coconut hybrid as the most promising planting material in the context of disease. To provide farmers with planting material that has high disease tolerance and also good agronomic characteristics, the study compared some basic traits ofthe coconut hybrid with other important coconut varieties with the objective of determining the suitability of the SGD x VTT as alternative planting material to revamp the coconut industry in Ghana. Mean sample size of 25 palms per coconut variety under the study was analyzed using two sample t-test procedure. The study indicated that the yield performance of the SGD x VTT coconut hybrid was better than the tall coconut types including the local West African Tall (WAT) and compared favourably with the Malayan Yellow Dwarf crossed Vanuatu Tall (MYD x VTT) coconut hybrid. The good agronomic characteristics of the SGD x VTT coupled with itshigh resistance to the CSPWD proved its suitability as alternative planting material to revamp the coconut industry in Ghana

The genetic architecture of the human cerebral cortex

The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder

Identification of receptor like kinase genes in coconut and development of a marker for validation of breeding materials resistant to a phytoplasma disease in Ghana

Cape St. Paul Wilt Disease (CSPWD) is a major factor that impacts on coconut productivity in Ghana. Novel markers that might be specific for a promising variety of coconut or that could validate the efficacy of crosses would be valuable for confidence in the identity of palms. This study couples the discovery of such a marker with a high throughput genotyping system based on high resolution melt curve analysis. Using oligonucleotides designed against kinase subdomains of receptor like kinases (RLKs) of other plant species, eight putative RLK genes were isolated from coconut, and the intron sequence of one of these analysed in more detail. Three single nucleotide polymorphisms (SNPs) were identified within this intron that could be used as a tractable marker to differentiate two distinct genotypes, and which could be differentiated using high resolution melt curve analysis. Analysis of different varieties of coconut used in the breeding programme included promising hybrids such as Sri Lanka Green Dwarf x Vanuatu Tall. F1 crosses between these palms had been self pollinated to generate F2 populations. Genotyping of palms at the RLK marker suggested that some F2 offspring of parent F1 palms may have been sired via cross pollination from neighbouring palms, a possibility that would bear significance for such breeding programmes.Key words: Coconut, genetic markers, receptor-like kinases, high resolution melt curve analysis, single nucleotide polymorphisms (SNPs)

Food security and nutrition in coconut based-households: A case study of Nvuma, Ghana

A food security and nutrition survey was conducted in 2005 on 25 coconut-based households at Nvuma and its environs, a typical coconut growing community in the Nzema East District of the Western Region, Ghana. The objective was to understand the concepts, determinants and consequences of food insecurity and hunger, as core indicators of nutrition, for future programme planning and implementation. Data was collected using a structured questionnaire administered through face-to-face interview. The mother in the household was the main respondent. The survey indicated a mean family size of seven. Majority of the respondents affirmed that there is food insecurity and nutrition is under threat. The children too have no access to a balanced diet. Adults cope with their food insecure conditions by borrowing money to buy or credit food, ateless per meal, skipping meals, substitute commonly eaten food with cheaper ones and ate the same kind of food or even going without food for a day or more. Some of them have taken up backyard gardening by planting cassava, plantain and vegetables to enhance their intake of coconut and oil palm products. Other food products such as milk and milk products, snacks, beef, etc are either eaten monthly or not at all. This reflects the poverty level in the community. Increased food production and availability in the market does not necessarily ensure food securityor improved nutrition to the individuals or at the household level as it may not be accessed by hunger-affected individuals or households