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

Screening for tolerance for iron toxicity

This study identified the appropriate time to visually score rice germplasm in order to select materials having the lowest yield reduction under iron toxicity. The experiment took place at Korhogo, 90 22' N 50 31' W, in northern C te d'Ivoire, during the wet season (May-Aug 1995) using a randomized complete block design with three replications on an irrigated Ultisol lowland that contained 343 ppm Fe in soil solution at the beginning of the season

Risk Prediction for Acute Kidney Injury in Acute Medical Admissions in the UK

Background Acute Kidney Injury (AKI) is associated with adverse outcomes; identifying patients who are at risk of developing AKI in hospital may lead to targeted prevention. This approach is advocated in national guidelines but is not well studied in acutely unwell medical patients. We therefore aimed to undertake a UK-wide study in acute medical units (AMUs) with the following aims: to define the proportion of acutely unwell medical patients who develop hospital-acquired AKI (hAKI); to determine risk factors associated with the development of hAKI; and to assess the feasibility of using these risk factors to develop an AKI risk prediction score. Methods In September 2016, a prospective multicentre cohort study across 72 UK AMUs was undertaken. Data were collected from all patients who presented over a 24-hour period. Chronic dialysis, community-acquired AKI (cAKI) and those with fewer than two creatinine measurements were subsequently excluded. The primary outcome was the development of h-AKI. Results 2,446 individuals were admitted to the AMUs of the 72 participating centres. 384 patients (16%) sustained AKI of whom 287 (75%) were cAKI and 97 (25%) were hAKI. After exclusions, 1,235 participants remained in whom chronic kidney disease (OR 3.08, 95% CI 1.96-4.83), diuretic prescription (OR 2.33, 95% CI 1.5-3.65), a lower haemoglobin concentration and an elevated serum bilirubin were independently associated with development of hAKI. Multivariable model discrimination was moderate (c-statistic 0.75), and this did not support the development of a robust clinical risk prediction score. Mortality was higher in those with hAKI (adjusted OR 5.22; 95% CI 2.23-12.20). Conclusion AKI in AMUs is common and associated with worse outcomes, with the majority of cases community acquired. The smaller proportion of hAKI cases, only moderate discrimination of prognostic risk factor modelling and the resource implications of widespread application of an AKI clinical risk score across all AMU admissions suggests that this approach is not currently justified. More targeted risk assessment or automated methods of calculating individual risk may be more appropriate alternatives

Some characteristics of the Sri Lanka Green Dwarf (SGD): a variety resistant to the Cape Saint Paul Wilt Disease of coconut

The Cape Saint Paul Wilt Disease (CSPWD), a lethal yellowing-type disease, has decimated thousands of hectares of coconut plantations in Ghana. Eighteen years of field screening showed varying levels of tolerance/resistance to the disease. Out of 27 different types screened only the Sri Lanka Green Dwarf (SGD) has so far shown complete resistance. This has been considered a very major step in finding a solution to the disease. Following this, studies were conducted on selected palms of SGD to have basic knowledge about some agronomic parameters and to assess the possibility of using the acquired knowledge to plan for future SGD improvement programmes. Characters studied included rate of germination, flower, stem, crown and leaf morphologies. The local West African Tall (WAT) variety was used as a check. The monoecious inflorescence was observed to be completely autogamous, as contrasted with the WAT, which exhibited partial to complete allogamy. Though the inflorescence of SGD had fewer number of female flowers (mean = 24.5) as compared to that of WAT (means = 32.15) a higher proportion of the flowers (34.4%) were set as nuts, resulting in higher number of matured nuts/palm in SGD. Other important observations made on SGD included fragile leaf and bunch attachments, and more susceptibility to insect attack. The implications of these observations make SGD unsuitable for release as a straight variety. Rather, it is being exploited in hybrid seed production with other tolerant types. JOURNAL OF THE GHANA SCIENCE ASSOCIATION Volume 2 No. 2 (2000) pp. 88-9

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)

Detection of lethal yellowing phytoplasma in embryos from coconut palms infected with Cape St Paul wilt disease in Ghana

This study investigated the potential of seed transmission of Cape St. Paul wilt disease (CSPWD) in coconuts. PCR amplification was used to assess the distribution of phytoplasmas in parts of West African Tall (WAT) palms infected with CSPWD. Employing phytoplasma universal primer pair P1/P7 in standard PCR, or followed with a nested PCR using CSPWD-specific primer pair G813f/AwkaSR, phytoplasma infection was detected in the trunks, peduncles, spikelets, male and female flowers of four infected WAT coconut palms. Through nested PCR, phytoplasma was also detected in four of 19 embryo DNA samples extracted individually from fruits harvested from three of the four infected palms and was confirmed as CSPWD by cloning and sequencing. Subsequently, CSPWD phytoplasma was again detected in five of 33 embryos from nine infected palms, and in one of eight fruits from two symptomless palms. Fruits from infected palms recorded higher percentage germinations in two field nurseries (average of 71.0%) compared to fruits from healthy palms (average of 57.6%), and matured fruits that had dropped from infected palms showed the same levels of germination as those harvested directly from the palms. This indicates that infected fruits retain the ability to germinate whether harvested or dropped. No phytoplasmas were detected in any of the resulting seedlings and plantlets obtained through embryo in-vitro culture. Therefore, although phytoplasma DNA can be detected in embryos, there is as yet no evidence that the pathogen is seed transmitted through to the seedling to cause disease in progeny palms