The influence of nitrogen application on the growth and mineral content of two African nightshade species (Solanum spp.) cultivated in Kenya

Plant growth, leaf nitrogen and nitrate-N, and chemical content of two African nightshades, Solanum villosum and S. sarrachoides under different nitrogen levels was investigated in field experiments in 2001 and 2004. Plants were supplied with 0, 1.3, 2.6 and 5.2 g N/plant. Both African nightshade species responded similarly to nitrogen supply. Leaf area and dry matter production of plants supplied with nitrogen was 4-8 times that of plants not supplied with nitrogen. Plants supplied with nitrogen had significantly higher specific leaf area but had a lower leaf to stem ratio (p≤0.05). Leaf nitrogen concentration was significantly higher (p≤0.05) in plants supplied with nitrogen. However, when expressed on a leaf area basis, the differences in the leaf nitrogen content between nitrogen treatments were minimal. Leaf blade nitrate-N tended to be high in young plants especially those that were supplied with nitrogen. The species showed significant differences (p≤0.05) in the mineral content. It was concluded that African nightshade responded to limited nitrogen by drastic reduction in leaf area to maintain the leaf nitrogen content.Key words: Leaf nitrogen, leaf to stem ratio, mineral content, nitrates, Solanum sarrachoides, Solanum villosu

The effect of biochar from rice husks on evapotranspiration, vegetative growth and fruit yield of greenhouse tomato cultivar Anna F1 grown in two soil types

Biochar made from crop residues has been shown to improve soil texture, soil porosity and soil structure. It can enhance fertilizer utilization, reduce leaching loses and hence improve nitrogen supply for plant growth. Utilization of biochar in preparation of potting substrates can enhance growth and yields of greenhouse tomato. A study was carried out to test the influence of rice husks biochar on substrate properties, growth and yield of greenhouse tomato. The experiment was carried as a factorial in completely randomized design with two factors: four biochar levels and two soil types, replicated three times. The biochar levels were volume ratios of 0 biochar: 1 soil (0Biochar), 0.25 biochar: 0.75 soil (0.25Biochar), 0.5 biochar: 0.5 soil (0.5Biochar) and 0.75 biochar: 0.25 soil (0.75Biochar). The two soil types used were the well drained deep red friable soil and imperfectly drained dark brown clay soil obtained from the University farm. Tomato Anna F1 was grown in four-liter plastic pots containing about 3 kg of soil-biochar mixture. Data were collected on the plant growth parameters of plant height, number of leaves per plant and plant dry weight upto the 8th - 9th week after transplanting, when fruit ripening began. The chlorophyll index of the leaves were measured using the SPAD meter. At harvesting, fresh weight and number of the fruits were determined. Incorporating biochar into potting substrate at 0.25-0.75 levels significantly increased evapotranspiration during early vegetative growth. This was indicative of biochar changing substrate properties mainly through significant reduction of bulk density and possibly increasing porosity. Biochar levels of 0.25-0.75 resulted in significant increases in vegetative growth and fruit yield of tomato. Adding biochar to the pot substrate increased tomato plant height, plant dry weight and fruit fresh weight by 21- 34%, 50-64% and 49%-56%, respectively. The increase in vegetative growth and fruit yield at 0.25-0.75 biochar levels was attributed to the positive effect of biochar on substrate physical properties. Plant height and number of leaves per plant had a significant linear relationship whose slope, the rate of increase in plant height with increase in number of leaves was not influenced by biochar levels. Biochar enhanced growth without changing the ratio of plant height to number of leaves of tomato. It is concluded that incorporation of biochar made from rice husks at 0.25 level can enhance greenhouse production in both red and clay soils. &nbsp

Bronchoscopy for Removal of Aspirated Tracheobronchial Foreign Bodies at Kenyatta National Hospital, in Kenya

Background: This study was aimed at defining the presentation, morbidity and mortality following inhalation and subsequent removal of  tracheobronchial foreign body using a rigid bronchoscope.Methods: This was a retrospective, cross-sectional study undertaken in the Ear Nose and Throat-Head and Neck Surgery Unit of Kenyatta National Hospital. The study population consisted of patients with brochoscopically proven tracheobronchial foreign body. Case notes of 107 consecutive admissions with brochoscopically verified tracheobronchial foreign bodieswere analyzed for age, sex, time interval between inhalation and removal, duration of stay in hospital, complications and mortality.Results: The vast majority of patients were below 3 years of age and 63% of them presented within 3 days after onset of symptoms. The right bronchus was the most frequent destination of inhaled foreign bodies (50.5%) followed by the left bronchus (17.8%) and carina (14.2%) inthat order. The turnover of patients with inhaled foreign bodies was high with 86.9% being discharged within 6 days after surgery. The bronchoscopic procedure was uneventful in 76.6% of patients. Repeat bronchoscopy was performed in three patients with one undergoing eventual thoracotomy.Intraoperative cardiac arrest occurred in 5 cases (4.6%) with successful resuscitation in 2 and mortality in three (2.7%) % cases.Conclusion: Bronchoscopic removal of inhaled foreign bodies remains one of the riskiest otolaryngologic emergencies in Kenyatta National Hospital partly because of involvement of the life sustaining airway and partly because of lack of ideal equipment and adequate expertise. The need for hands on experience and close cooperation and familiarity between theanaesthesiologist and the bonchoscopist is emphasized

Microbiology of chronic suppurative otitis media at Queen Elizabeth Central Hospital, Blantyre, Malawi: A cross-sectional descriptive study

Background Chronic suppurative otitis media (CSOM) is still a significant health problem in developing countries. Therefore, it was pertinent to determine the local Malawian microbiology in order to guide adequate treatment, avoid complications, and provide records for future reference.Aim The study sought to determine the CSOM-causing microorganisms at Queen Elizabeth Central Hospital in Blantyre, Malawi, and establish their relationship signs and symptoms, and with the demographic pattern of the study.Methods This was a hospital-based cross-sectional descriptive study carried out at the ENT outpatient clinic and the Microbiology Department of Queen Elizabeth Central Hospital.The sample comprised 104 patients with unilateral or bilateral active CSOM, who met the inclusion criteria. All patients were evaluated through a detailed history and clinical examination. Pus samples from draining ears were collected by aspiration with a sterile pipette. The specimens were immediately sent for microbiological analysis. Data were analyzed using SPSS.version 20.Results The study found that Proteus mirabilis, Pseudomonas aeruginosa, and Staphylococcus aureus were the most prevalent aerobic bacteria, while Bacteroides spp. and Peptostreptococcus spp. were the commonest anaerobic bacteria causing CSOM. These CSOM-causing microorganisms were predominant among males aged 18 years and below. Some CSOMcausing microorganisms were—significantly more so than the others—characteristically associated with each of the following clinical features: quantity of pus drainage, mode of onset, otalgia, hearing loss, location of tympanic membrane perforation, and mucosal appearance