Effects of disinfection, packaging and evaporatively cooled storage on sugar content of mango

The present investigation was undertaken to evaluate the effect of post-harvest disinfection, packaging, evaporative cooling storage and their combined effect on the changes in sugar content ofmango (Mangifera indica L.). The experiment was laid out in a factorial combination of disinfection, packaging and storage in a randomized complete block design with three replications. The mangoeswere periodically analyzed for reducing sugar and total sugar. Non-reducing sugar was computed from the difference between experimental reducing and total sugars. Storage conditions significantly (P 0.01) affected sugar content in mangoes. Storage at ambient conditions with higher temperature and lower relative humidity as compared to the evaporatively cooled storage resulted in rapid deterioration in sugar content of the mangoes. During the storage period, packaging generally maintained higher (P 0.01) levels of reducing sugar, non-reducing sugar and total sugar. Similarly, disinfection treatment significantly (P 0.01) affected the changes in reducing, non-reducing and total sugars of mangoes during storage. Two-way interactions were significant (P 0.01) in terms of the changes in sugar content of mangoes. The benefits of the combined effect of post-harvest treatments on mangoes included maintenance of high reducing sugar, non-reducing sugar and total sugar

Managing acid soils for reclaiming livelihoods in Ethiopia

Soil acidification is the result of a complex set of processes caused both naturally and by human activity. It limits plant growth because of conditions that increase base element deficiencies, Phosphorus-fixation and toxicities of Aluminum, Manganese and Hydrogen ions

Health Extension Workers' diagnostic accuracy for common childhood illnesses in four regions of Ethiopia: a cross-sectional study.

AIM: The Ethiopian primary care of sick children is provided within the integrated Community Case Management of childhood illnesses by Health Extension Workers (HEW). There is limited knowledge whether this cadre correctly assess and classify common diseases. The aim was to study their ability to correctly classify common childhood illnesses. METHODS: A survey was conducted from December 2016 to February 2017 in four regions of Ethiopia. Observations of the HEWs' assessment and classification of sick children were followed by child re-examination by a trained health officer. RESULTS: The classification by the HEWs of 620 sick children as compared to the re-examiner had a sensitivity of 89% and specificity of 94% for diarrhoea, sensitivity 52% and specificity 91% for febrile disorders, and a sensitivity of 59% and specificity of 94% for acute respiratory tract infection. Malnutrition and ear infection had a sensitivity of 39 and 61%, and a specificity of 99 and 99%, respectively. CONCLUSION: Most cases of diarrhoea were correctly classified, while other illnesses were not frequently identified. The identification of malnutrition was especially at fault. These findings suggest that a significant number of sick children were undiagnosed that could lead to absent or incorrect management and treatment

Grain yield, stem borer and disease resistance of new maize hybrids in Kenya

Evaluation of 30 maize hybrids for yield and resistance to stem borers and foliar diseases in four agroecologies in Kenya was conducted in 2009. There were significant differences among the hybrids in leaf damage, number of exit holes, tunnel length and grain yield in Kiboko. The maize hybrids CKPH08014, CKPH08025, and CKPH08026 showed the least leaf damage, exit holes and tunnel length, similar to the resistant check. Although ten hybrids yielded over 8 t/ha, two hybrids, CKPH09001 and CKPH08033, gave the highest yield of 8.99 and 8.86 t/ha, respectively, in Kiboko. There were significant differences among the hybrids in resistance to leaf rust and maize streak virus in Kakamega. The intensity of foliar diseases was high in Kakamega compared to the other sites. All hybrids appeared resistant to the foliar diseases at Kakamega. On the average, the highest yield of the hybrids was recorded in Kiboko (7.5 t/ha) followed by Kakamega (6.1 t/ha), and the least at Embu (3.5 t/ha), and Mtwapa (3.14 t/ha). The performance of the hybrids varied from site to site, with CKPH09002 and CKPH09003 performing well at Mtwapa, CKPH09001 at Kiboko, CKPH08039 at Embu, CKPH 08002 and CKPH08010 at Kakamega.Key words: Host plant resistance, maize, pest management, stem borer, foliar disease

Resistance of maize varieties to the maize weevil Sitophilus zeamais (Motsch.) (Coleoptera: Curculionidae)

This study aimed at evaluating commonly used maize varieties, collected from Melkasa and Bako Agricultural Research Centers and Haramaya University, Ethiopia, against the maize weevil Sitophilus zeamais Motsch., one of the most important cosmopolitan stored product pests in maize. A total of 13 improved maize varieties were screened for their relative susceptibility to S. zeamais. The Dobie index of susceptibility was used to group the varieties. The variety, ‘BHQP-542’, had the least index ofsusceptibility and was regarded as resistant. The varieties, ‘Katumani’, ‘Melkasa-I’, ‘Melkasa-II’, ‘Melkasa-III’, ‘Coree’, ‘BH-541’, ‘BH-660’, ‘BH-540’, ‘Rare-I’, ‘Awasa-511’, ‘ACV3’ and ‘ACV6’, were moderately resistant. Weevils fed with the resistant variety produced low numbers of F1 progeny, had a high median developmental time and a low percentage of seed damage and seed weight loss. Maize varieties with a high F1 progeny tended to have a short median developmental time. An increasingnumber of F1 progeny resulted in an increasing seed damage and seed weight loss. We found an inverse relationship between the susceptibility index and percent mortality and median developmental time; however, the numbers of F1 progeny, percent seed damage and seed weight loss were positively related with the susceptibility index. The use of resistant varieties should be promoted in managing S.zeamais in stored maize under subsistence farming conditions in Africa

Seed quality and mycoflora associated with chickpea (Cicer arientinum L.) seed in Ethiopia

The study was conducted at Ethiopian Institute of Agricultural Research, Haramaya University and Jimma University, Ethiopia. Crop yield is directly associated with the physical and biological quality of planting material or seed. Ninety-nine (99) chickpea seed lot samples were collected for physical purity, seed health and germination tests from major chickpea growing areas in Ethiopia in the 2016/17 cropping season to assess the status of chickpea seed health and quality among subsistence farmers, research stations and seed growers. The seed lots were grouped as researcher saved, farmers saved and seed growers’ saved seed. The maximum physical purity of 97.5% was recorded for the researcher saved seed lots, 90.8% for the seed growers and 87.4 % for the farmers saved seeds. Foreign matters and broken seeds were the most contaminants found in the seed lots. The seed germination percentages were in the range of 96.3% to 98.5% for all seed sources and there were no significant differences among the seed lot samples. A total of seventeen (17) fungi species were isolated from all seed sources with different frequency and amount. These are Fusarium spp., Aspergillus sp., A. niger, A. flavus, A. nidulans, A. candidus, A. fumigatus, Penicillium sp., Rhizopus sp., Verticillium sp., Rhizoctonia sp., Pythium sp., Alternaria sp., Helminthosporium sp. Phylostica sp., Cladosporium sp., Negrospora sp. Aspergillus flavus was found the most dominant  with recovery (Relative Density=21.53%, Infection rate=10.36%, and Infection Frequency=25.59 %) from all seed lots. There were high variations in relative density, Infection rate, and Infection frequency among isolated fungi. Ascochyta rabiei the most important  chickpea disease was not found in this study. This might relate to the incidence and prevalence of sample collection season/cropping year which was low in expected areas. The current study concluded that there are seed qualities and seed health management issues with regards to different seed sources (farmers, research and private sectors); this entails strong seed quality control and growers’ awareness creation on storage sanitation, seed health test before sowing, and production of healthy crops. To keep the seed health in a better condition, seed growers should keep a wider interval of rotation, develop use of the healthy improved seed, after some  generation (4-5), seed grading to avoid loss of physical purity, use of appropriate storage container (ventilated and clean), seed dressing with safe pesticides, and appropriate moisture level for storage (about 14%) should have to keep. Longer storage also gives a chance to contaminate the whole seed and can expose to decay. Key words: Chickpea, fungi, germination, mycoflora, purity, seed health, seed source

Responses of tropical maize landraces to damage by Chilo partellus stem borer

The potential to manage insect pests using host-plant resistance exists, but has not been exploited adequately. The objective of this study was to determine the resistance of 75 tropical maize landraces through artificial infestation with Chilo partellus Swinhoe. The trial was laid in alpha-lattice design and each seedling was infested with five neonates three weeks after planting, over two seasons in 2009 and 2010. The number of exit holes, tunnel length, ear diameter, ear length, plant height, stem diameter, stem lodging and grain yield were measured and a selection index computed. GUAT 1050 was the most resistant with an index of 0.56, while BRAZ 2179 was the most susceptible with an index of 1.66. Ear characteristics were negatively correlated with damage parameters. The principal component biplot suggested that exit holes, cumulative tunnel length, leaf damage, cob diameter, stem lodging, selection index, ear and plant height contributed 71.2% of the variation in resistance. The mean number of exit holes and tunnel length for resistant landraces and resistant hybrid checks were similar; at 5.5 and 2.48 cm, respectively. The identified resistant landraces (GUAT 1050, GUAT 280, GUAT 1093, GUAT 1082, GUAT 1014, CHIS 114, and GUAN 34) could be used to develop C. partellus stem borer-resistant maize genotypes.Key words: Chilo partellus, ear length, exit holes, stem borer resistance, tunnel length

Genotype by environment interactions and yield stability of stem borer resistant maize hybrids in Kenya

In a maize breeding program, potential genotypes are usually evaluated in different environments before desirable ones are selected. Genotype x environment (G x E) interaction is associated with the differential performance of genotypes tested at different locations and in different years, and influences selection and recommendation of cultivars. Twenty one stem borer resistance maize hybrids and four commercial checks were evaluated in six environments in Kenya under infestation with Chilo partellus and Busseola fusca to determine the G x E interactions and stability of the hybrids. Analysis of variance was conducted for grain yield, days to flowering and plant and ear height. Stability for grain yield was determined using genotype plus genotype by environment interaction (GGE) biplot analysis. Variances due to genotype, environment and G x E interaction effects were highly significant for all traits. The GGE biplot showed that four experimental hybrids and two commercial checks had positive PC1 score indicating above average performance across environments. However, 10 experimental hybrids and two commercial checks had negative PC1 score, suggesting poor average performance. Experimental hybrids, CKIR07004 and CKIR07013, were highly desirable in terms of grain yield (>7.5 t/ha) and stability across environments. These hybrids could be released in Kenya and similar environments.Key words: Genotype x environment (G x E) interactions, maize, stem borer resistant hybrids, stability