Plasticity of root hair and rhizosheath traits and their relationship to phosphorus uptake in sorghum.

Sorghum is an essential crop for resilient and adaptive responses to climate change. The root systems of crop plants significantly contribute to the tolerance of abiotic stresses. There is little information on sorghum genotypes' root systems and plasticity to external P supply. In this paper, we investigated the variations in root systems, as well as the responses, trait relationships, and plasticity of two sorghum genotypes (Naga Red and Naga White), popularly grown in Ghana, to five external P concentrations ([P]ext): 0, 100, 200, 300, and 400 mg P kg-1 soil. Sorghum plants were grown in greenhouse pots and harvested for root trait measurements at the five-leaf and growing point differentiation (GPD) developmental stages. The plants were responsive to [P]ext and formed rhizosheaths. The two genotypes showed similar characteristics for most of the traits measured but differed significantly in total and lateral root lengths in favor of the red genotype. For example, at the five-leaf growth stage, the lateral root length of the red and white genotypes was 22.8 and 16.2 cm, respectively, but 124 and 88.9 cm, at the GPD stage. The responses and plasticity of the root system traits, including rhizosheath, to [P]ext were more prominent, positive, and linear at the five-leaf stage than at the GPD growth stage. At the five-leaf growth stage, total root length increased by about 2.5-fold with increasing [P]ext compared to the unamended soil. At the GPD stage, however, total root length decreased by about 1.83-fold as [P]ext increased compared to the unamended soil. Specific rhizosheath weight correlated with RHD, albeit weakly, and together explained up to 59% of the variation in tissue P. Root hair density was more responsive to P supply than root hair length and showed a similar total and lateral root length pattern. Most desirable responses to P occurred at a rate of 200-300 mg P kg-1 soil. It is concluded that sorghum would form rhizosheath, and [P]ext could be critical for the early vigorous growth of sorghum's responsive root and shoot traits. Beyond the early days of development, additional P application might be necessary to sustain the responses and plasticity observed during the early growth period, but this requires further investigation, potentially under field conditions.

Clinical characteristics of external bacterial ocular and periocular infections and their antimicrobial treatment patterns among a Ghanaian ophthalmic population.

Empirical antimicrobial therapy is linked to a surge in antimicrobial resistant infections. However, an insight on the bacteria etiology of ocular infections is essential in the appropriation of choice of antimicrobial among clinicians, yet there remains a dearth of data from Ghana. We investigated the bacteria etiology of external ocular and periocular infections and antimicrobial treatment patterns among a Ghanaian ophthalmic population. A multicenter study design with purposive sampling approach was employed. Patients demographics and clinical data were collated using a pretested structure questionnaire. Cornea specimens and conjunctival swabs were obtained for bacterial isolation following standard protocols. About 95% (98/103) of ocular samples were positive for bacteria culture. The proportion of Gram-negative bacteria was 58.2%, and the predominant bacteria species were Pseudomonas aeruginosa 38.8% and Staphylococcus aureus 27.6%. Conjunctivitis 40.0% and keratitis 75.0% were mostly caused by Pseudomonas aeruginosa. The routinely administered antimicrobial therapy were polymyxin B 41.2%, neomycin 35.1% and ciprofloxacin 31.6%. Participants demographic and clinical characteristics were unrelated with positive bacteria culture (p > 0.05). Our results showed a markedly high burden of ocular bacterial infections and variations in etiology. Bacterial infection-control and antimicrobial agent management programs should be urgently institutionalized to prevent the emergence of resistant infections.

Root System Traits Contribute to Variability and Plasticity in Response to Phosphorus Fertilization in 2 Field-Grown Sorghum [Sorghum bicolor (L.) Moench] Cultivars.

Due to roots' physical and physiological roles in crop productivity, interest in root system architecture (RSA) and plasticity in responses to abiotic stresses is growing. Sorghum is significant for the food security of millions of people. Phosphorus deficiency is an important limitation of sorghum productivity. There is little information on the RSA-based responses of sorghum to variations in external P supply ([P]ext). This study evaluated the phenotypic plasticity and RSA responses to a range of [P]ext in 2 sorghum genotypes. The results showed that both genotypes responded to [P]ext but with significant variations in about 80% of the RSA traits analyzed. Aboveground biomass and most RSA traits increased with increasing [P]ext. Plasticity was both genotype- and trait-dependent. For most RSA traits, the white sorghum genotype showed significantly higher plasticity than the red genotype, with the former having about 28.4% higher total plasticity than the former. RSA traits, such as convex area, surface area, total root length, and length diameter ranges, showed sizeable genetic variability. Root biomass had a high degree of plasticity, but root number and angle traits were the leading contributors to variation. The results suggested 2 root trait spectra: root exploration and developmental spectrum, and there was an indication of potential trade-offs among groups of root traits. It is concluded that RSA traits in sorghum contribute to variability and plasticity in response to [P]ext. Given that there might be trade-offs among sorghum root traits, it would be instructive to determine the fundamental constraints underlying these trade-offs.

Orbital Apex Syndrome: a rare complication of herpes zoster ophthalmicus in a Ghanaian woman living with HIV.

Herpes Zoster Ophthalmicus (HZO) usually affects the immunocompromised and aged. It results from the reactivation of latent varicella zoster infection in the trigeminal ganglia. Orbital apex syndrome (OAS) is a rare sequela of the disease and tends to be disfiguring and vision-threatening if not addressed. We report on a 43-year-old Ghanaian female living with Human Immunodeficiency Virus infection and on highly active antiretroviral therapy who presented with a 2-month history of a healed vesicular rash left side of the forehead and a droopy left upper eyelid. On examination, she had complete ptosis, visual acuity in the left eye was 6/36, and restricted mobility in all directions of gaze. On anterior segment examination using a slit lamp biomicroscope, the left eye had mild cornea oedema with keratic precipitates and relative afferent pupillary defect (RAPD). Intraocular pressure and posterior segment of the right eye were normal. Computed tomography (CT) Scan of the head was taken to rule out other causes of OAS. Patient was treated with oral acyclovir 400mg five times daily for 30 days, topical steroids and oral prednisolone 60mg daily for 30 days which was tapered. Ptosis improved significantly with mild supraduction and infraduction deficit. Visual acuity improved to 6/12 and all keratic precipitates cleared. The patient, however, developed a corneal scar from a possible neurotrophic ulcer after defaulting treatment for 11 months. OAS , as a rare sequalae of HZO, responds well to oral acyclovir and steroids. Prompt diagnosis and appropriate treatment, even at late presentation, yield positive outcomes. Funding: None declared.

Assessment of corneal astigmatism following frown and straight incision forms in sutureless manual small incision cataract surgery.

To investigate which of two tunnel incision forms (frown versus straight) in sutureless manual small incision cataract surgery creates more corneal astigmatism. Sixty eyes of 60 patients who had consented to undergo cataract surgery and to partake in this study were followed from baseline through >12-week postoperative period. Values of preoperative and postoperative corneal astigmatism for the 60 eyes, measured with a Bausch and Lomb keratometer, were extracted from the patients' cataract surgery records. Residual astigmatism was computed as the difference between preoperative and postoperative keratometry readings. Visual acuity was assessed during the preoperative period and at each postoperative visit with a Snellen chart at 6 m. Fifty eyes of 50 patients were successfully followed-up on. Overall, the mean residual astigmatism was 0.75±0.12 diopters. The differences in mean residual astigmatism between the two different incision groups were statistically significant (t [48]=6.33, P<0.05); frown incision group recorded 1.00±0.12 diopters, whereas the straight incision group recorded 0.50±0.12 diopters. No significant difference was observed between male and female groups (t [48]=0.24, P>0.05). Residual corneal astigmatism in the frown incision group was significantly higher than in the straight incision group. Fisher's exact test did not reveal a significant association between incision forms and visual acuity during the entire postoperative period (P>0.05).