Tuberization and effect of age of seedlings at transplant on yield of seed-propagated cassava

Two experiments were carried out firstly to study the processes of development and tuber initiation in cassava seedlings, and secondly, to determine the appropriate age at which cassava seedlings should be transplanted to ensure optimum field establishment and higher yield. In the first experiment, nursed seedlings were uprooted at weekly intervals from time of emergence for 9 weeks, and observed for root and shoot development. Transverse sections of roots were examined for the presence of starch grains. In the second experiment, seedlings at 27, 34, 41 and 48 days old were transplanted (naked root) to the field and observed for survival and tuber yield after 10 months of growth. Most seeds germinated within 7-16 days after sowing but a few germinated after 70 days. During the first 9 weeks of seedling growth, an average of three leaves unfolded every week on the main stem. Stem elongation occurred at a fairly constant rate of 5.1 mm /day while tap root elongation was 8.6 mm/day for the first week, and 2.4 mm/day over the next 6 weeks. Lateral root elongation was high, averaging about 9.3 mm/day over the first 6 weeks of growth. Starch grains were first observed in the tap root at 4 weeks and in the lateral root tissues at 5 weeks. Proliferation of starch-filled cortical cells began in the tap and lateral roots at 5 and 9 weeks respectively. Percentage survival were 28, 63, 80, and 67 for seedlings transplanted at 27, 34, 41 and 48 days old respectively. Tuber yield ranged from 6525 kg/ha for the 27 days old seedlings to 17 764 kg/ha for the 41 days old seedlings. It was concluded that the most appropriate age at which to transplant cassava seedlings to ensure optimum survival and yield was 41 days after sowing. (Ghana Journal of Agricultural Science, 1997, 30(1): 9-14

Collection and Conservation of Root and Tuber Crops in Ghana

Collection and conservation of root and tuber crop genetic resource are important exercises that safeguard their genetic diversity for future and crop improvement purposes. The Plant Genetic Resources Research Institute (PGRRI) has long been involved in the conservation of root and tuber crops in Ghana. This paper aims at highlighting strides made by the PGRRI in the collection and conservation of root and tuber crops in Ghana. Root and tuber crops genetic resource collection in PGRRI dates back to 1965. Between 1965 and 2015, 2497 accessions of root and tuber crops were collected throughout Ghana and documented. Most of the root and tuber crops assembled were collected within Ashanti, Brong Ahafo and the Eastern regions of Ghana. Germplasm of yam, cassava, taro, cocoyam, sweetpotato and Frafra potato were collected. Cultivatable samples were collected from farms, markets, barns and the wild. Samples were multiplied on-station to acquire adequate quantities for conservation. Yam was the most collected root and tuber crop in Ghana. Seven (7) yam species were collected and constituted 52% of the total germplasm collected within the period. Root and tuber crops are conserved as life plants ex-situ in the field genebank and duplicates are also conserved in vitro at PGRRI. Research studies carried out on the root and tuber genetic resources included; agro-morphological characterization and evaluation against biotic and abiotic agents.Key words: Collecting, Conservation, Root and Tuber Crops, Genetic Resources, AccessionCollecte et Conservation Des Racines et Tubercules au Ghana Les cultures de racines et tubercules sont les cultures vivrières les plus importantes pour la consommation humaine en Afrique. L'adaptabilité à diverses agro-écologies, le rendement élevé par unité de surface de terre et la qualité nutritionnelle en font des cultures de choix pour les programmes de sécurité alimentaire en Afrique. La collecte et la conservation des ressources génétiques des racines et tubercules sont des exercices importants qui préservent leur diversité génétique pour l'avenir et l'amélioration des cultures. L'Institut de recherche sur les ressources phytogénétiques (PGRRI) a engage à la conservation des racines et tubercules au Ghana. Cet article vise à souligner les progrès réalisés par le PGRRI dans la collecte et la conservation des cultures de racines et tubercules au Ghana. La collecte des ressources génétiques des racines et des tubercules dans le PGRRI remonte à 1965. Entre 1965 et 2015, 2497 des variétés de cultures de racines et de tubercules ont été collectées dans tout le Ghana et documentées. La plupart des plantes de racines et tubercules assemblées ont été récoltées à Ashanti, Brong Ahafo et dans les régions orientales du Ghana. Le matériel génétique d'igname, du manioc, du taro, de la patate douce et de la pomme de terre Frafra, a été recueilli. Des échantillons cultivables ont été recueillis dans les fermes, les marchés, les étables et la nature. Les échantillons ont été multipliés en station pour acquérir des quantités suffisantes pour la conservation. L'igname était la culture de racines et tubercules la plus collectée au Ghana. Sept (7) espèces d'igname ont été collectées et constituaient 52% du germoplasme total collecté durant cette période. Les cultures de racines et de tubercules sont conservées en tant que plantes vivantes ex-situ dans la banque de gènes sur le terrain et les doubles sont conservés sous conservation in vitro à PGRRI. Les activités de recherche menées sur les ressources génétiques des racines et tubercules comprennent; caractérisation agro-morphologique et évaluation contre les agents biotiques et abiotiques.Mots clés: Collecte, Conservation, Cultures de Racines et Tubercules, Ressources Génétiques, variété

Career intentions of medical students in the UK: a national, cross-sectional study (AIMS study)

Objective To determine current UK medical students’ career intentions after graduation and on completing the Foundation Programme (FP), and to ascertain the motivations behind these intentions.Design Cross-sectional, mixed-methods survey of UK medical students, using a non-random sampling method.Setting All 44 UK medical schools recognised by the General Medical Council.Participants All UK medical students were eligible to participate. The study sample consisted of 10 486 participants, approximately 25.50% of the medical student population.Outcome measures Career intentions of medical students postgraduation and post-FP, motivations behind these career intentions, characterising the medical student population and correlating demographic factors and propensity to leave the National Health Service (NHS).Results The majority of participating students (8806/10 486, 83.98%) planned to complete both years of the FP after graduation, with under half of these students (4294/8806, 48.76%) intending to pursue specialty training thereafter. A subanalysis of career intentions after the FP by year of study revealed a significant decrease in students’ intentions to enter specialty training as they advanced through medical school. Approximately a third of surveyed students (3392/10 486, 32.35%) intended to emigrate to practise medicine, with 42.57% (n=1444) of those students not planning to return. In total, 2.89% of students intended to leave medicine altogether (n=303). Remuneration, work-life balance and working conditions were identified as important factors in decision-making regarding emigration and leaving the profession. Subgroup analyses based on gender, type of schooling, fee type and educational background were performed. Only 17.26% of surveyed students were satisfied or very satisfied with the overall prospect of working in the NHS.Conclusions The Ascertaining the career Intentions of UK Medical Students study highlights UK students’ views and career intentions, revealing a concerning proportion of those surveyed considering alternative careers or emigration. Addressing factors such as remuneration, work-life balance and working conditions may increase retention of doctors and improve workforce planning efforts

The role of medical schools in UK students’ career intentions: findings from the AIMS study

Abstract Objectives To investigate differences in students’ career intentions between UK medical schools. Design Cross-sectional, mixed-methods online survey. Setting The primary study included all 44 UK medical schools, with this analysis comprising 42 medical schools. Participants Ten thousand four hundred eighty-six UK medical students. Main outcome measures Career intentions of medical students, focusing on differences between medical schools. Secondary outcomes included variation in medical students’ satisfaction with a prospective career in the NHS, by medical school. Results 2.89% of students intended to leave medicine altogether, with Cambridge Medical School having the highest proportion of such respondents. 32.35% of respondents planned to emigrate for practice, with Ulster medical students being the most likely. Of those intending to emigrate, the University of Central Lancashire saw the highest proportion stating no intentions to return. Cardiff Medical School had the greatest percentage of students intending to assume non-training clinical posts after completing FY2. 35.23% of participating medical students intended to leave the NHS within 2 years of graduating, with Brighton and Sussex holding the highest proportion of these respondents. Only 17.26% were satisfied with the prospect of working in the NHS, with considerable variation nationally; Barts and the London medical students had the highest rates of dissatisfaction. Conclusions This study reveals variability in students’ career sentiment across UK medical schools, emphasising the need for attention to factors influencing these trends. A concerning proportion of students intend to exit the NHS within 2 years of graduating, with substantial variation between institutions. Students’ intentions may be shaped by various factors, including curriculum focus and recruitment practices. It is imperative to re-evaluate these aspects within medical schools, whilst considering the wider national context, to improve student perceptions towards an NHS career. Future research should target underlying causes for these disparities to facilitate improvements to career satisfaction and retention. </jats:sec