Tessema Astatkie

Thermal imaging of soybean response to drought stress: the effect of Ascophyllum nodosum seaweed extract

Previous experiments have demonstrated positive effect of Acadian® extract of Ascophyllum nodosum on plant stress-resistance, however the mode of action is not fully understood. The aim of this study was to understand the physiological effect of Acadian® seaweed extract on the plant response to drought stress. Leaf temperature and leaf angle were measured as early-stage indicators of plant stress with thermal imaging “in situ” over a 5-day stress-recovery trial. The early stress-response of control became visible on the third day as a rapid wilting of leaves, accompanied with the asymptotic increase of leaf temperature on 4–5xa0°C to the thermal equilibrium with ambient air temperature. At the same time Acadian® treated plants still maintained turgor, accompanied with the linear increase in leaf temperature, which indicated better control of stomatal closure. Re-watering on the fifth day showed better survival of treated plants compared to control. This study demonstrated the ability of Acadian® seaweed extract to improve resistance of soybean plants to water stress.

Ideal body condition improves reproductive performance and influences genetic health in female mink

Selection for large body size in mink (Neovison vison) can result in obesity, which is associated with poor reproduction and metabolic disorders. Caloric restriction is effective in diminishing oxidative stress and delaying aging-related diseases. This study investigated the effects of moderate diet restriction on body condition, health, and reproductive success of mink breeder females. One-hundred control females were fed according to conventional feeding practice, while the feed allowance of their 100 sister-pair females was restricted in order to maintain an ideal body condition during the fall and eliminate the need for drastic slimming prior to breeding. Repeated measures analyses revealed that body weight gain during the fall and weight loss prior to breeding was significantly less for the restricted females. The restricted females had significantly larger live litters (5.88 kits) than the control dams (4.62 kits; P<0.05). They were also able to maintain their body weight and condition during early lactation and were able to regain weight and condition post-lactation, unlike their control sisters. Based on their comet scores (restricted: 88; control: 116), the restricted primiparous females experienced less DNA damage (P<0.05), while no significant differences were apparent for the multiparous females (restricted: 170; control: 153). No changes in telomere length were observed among the dams. Moderate diet restriction of mink breeder females during the fall eliminated extreme fluctuations in body weight and condition throughout the seasonal production cycle and improved their litter size, and in primiparous females, lessened DNA damage.

Nutritional quality and acceptability of sweet potato–soybean–moringa composite porridge

Purpose – The purpose of this paper was to formulate porridge using orange-fleshed sweet potato (OFSP), soybean and moringa ingredients that optimizes its nutritional quality and acceptability. Design/methodology/approach – A 16-run constrained D-optimal mixture design was used to evaluate proximate compositions and sensory acceptability of the products. Each composition and acceptability response variable was optimized separately, and then, the sweet spot that optimizes all was determined. Findings – The protein, fiber, total ash, carbohydrate, iron and carotenoid contents as well as major sensory quality indicators were significantly affected by soybean, moringa and OFSP blends. However, the influence of the mixture on fat content was weak. Sensory acceptability was high for porridges processed from high OFSP and soybean, but higher nutritional quality was obtained from higher moringa levels. Graphical optimization showed that blends containing 68-75 per cent OFSP, 17-26 per cent soybean and 5-8 per cen...

Evidence of endoplasmic reticulum stress and liver inflammation in the American mink Neovison vison with benign hepatic steatosis

We investigated the presence of inflammatory signs in the progression of fatty liver disease induced by fasting. Sixty standard black American mink (Neovison vison) were fasted for 0, 1, 3, 5, or 7xa0days and one group for 7xa0days followed by re-feeding for 28xa0days. Liver sections were evaluated histologically and liver mRNA levels indicating endoplasmic reticulum (ER) stress, adipogenic transformation, and inflammation were assessed by quantitative real-time PCR. After 3xa0days of fasting, the mink had developed moderate liver steatosis. Increased hyaluronan reactivity in lymphocytic foci but no Mallory–Denk bodies were seen in livers of the mink fasted for 5–7xa0days. Up-regulation of glucose-regulated protein, 78xa0kDa was observed on day 7 indicating ER stress, especially in the females. Liver lipoprotein lipase and monocyte chemoattractant protein 1 mRNA levels increased in response to 5–7xa0days of food deprivation, while tumor necrosis factor α (TNF-α) was the highest in the mink fasted for 5xa0days. The expression of the genes of interest, except for TNF-α, correlated with each other and with the liver fat content. The mRNA levels were found to change more rapidly below n-3/n-6 polyunsaturated fatty acid ratio threshold of 0.15. Following re-feeding, hepatocyte morphology and mRNA abundance returned to pre-fasting levels. Within the studied timeframe, evidence for ER stress, adipogenic transformation, and liver inflammation suggested incipient transition from steatosis to steatohepatitis with potential for development of more severe liver disease. This may present a possibility to influence disease progression before histologically observable steatohepatitis.

Inorganic and organic liquid fertilizer effects on growth and yield of onion

ABSTRACT The Government of Ethiopia recently introduced a new synthetic compound fertilizer (NPS; 19% N, 38% P2O5, and 7% S) for blending with K, Zn, and B. The performance of NPS, and whether blending it with organic liquid fertilizer (OLF), improves growth and productivity of onion (Allium cepa L.) has not been studied. The experiment was conducted in the Gurage zone, Ethiopia, from June to September 2016 to identify the best combination of NPS and OLF to increase onion productivity. Combinations of NPS and OLF used were 0, 400, or 500 L∙ha−1 OLF and 0, 150, or 200 kg∙ha−1 of NPS. The interaction of NPS and OLF affected plant height, leaf number, bulb diameter, and bulb dry weight with the highest mean values (43.6 cm, 7.73/plant, 5.14 cm, and 20.8 g/bulb) obtained from 400 L∙ha−1 OLF+0 NPS, 0 OLF+200 kg∙ha−1 NPS, 400 L∙ha−1 OLF+0 NPS, and 400 L∙ha−1 OLF+200 kg∙ha−1 NPS, respectively. The main effect of OLF affected onion leaf length, total bulb yield, and bulb fresh weight with the highest values obtained from 400, 500, and 500 L∙ha−1 OLF were 36.5 cm, 46.2 t∙ha−1, and 46.8 g/bulb, respectively. The main effect of NPS affected total bulb yield, with the highest yield, 46.1 kg∙ha−1, obtained from 200 kg∙ha−1 NPS. Growth and yield attributes were influenced differently by OLF and NPS fertilizers, indicating that there is an opportunity to customize combinations of OLF and NPS to increase productivity of red onion.

Effect of brewery spent diatomite sludge on trace metal availability in soil and uptake by wheat crop, and trace metal risk on human health through the consumption of wheat grain

Soil plays a crucial role in food safety as it determines the composition of food at the beginning of the food chain. However, the quality of soil resources in terms of their potential impact on human health caused by harmful elements is poorly understood in Ethiopia due to lack of reliable and appropriate experimental data. In this study, a field experiment was conducted to evaluate trace metal accumulation in soils amended with brewery spent diatomite sludge (BSDS) in comparison to control, recommended inorganic fertilizers (RIF) and integrated BSDS & RIF (BSDS:RIF). Trace metals uptake by wheat crop and the degree of soil contamination, and human health risk were investigated. BSDS application significantly increased the concentration of trace metals (Cu, Zn, Pb and Ni) in soil compared to that in the control, the RIF, and BSDS:RIF applications. It also significantly increased the concentration of Cu, Zn, Pb and Ni in the wheat grain compared to that in the control and the RIF, but the increase was not significantly different from that in BSDS:RIF amendment. All trace metal concentrations in soil and wheat grain (except Pb in wheat grain) were below the maximum permissible limits in some European countries of agricultural soils, and the maximum permissible limit of FAO/WHO. The degree of soil contamination from each of the treatments was below the maximum acceptable degree of contamination. The Health Risk Index (HRI) was <1 for all metals in all treatments. Thus, we conclude that consumption of wheat grain grown on soils amended with BSDS and BSDS:RIF has no human risks and has low likelihood of human exposure to trace metals.

Effect of variety and drying temperature on physicochemical quality, functional property, and sensory acceptability of dried onion powder

Abstract In Ethiopia, onion is one of the most important vegetables/spices produced as a source of cash income and for flavoring foods. However, postharvest loss during storage remains a major challenge. In this study, the effects of variety (Bombay red, Qellafo and Sweet carolin) and drying temperature (Fresh, 50, 60, 70, 80, and 90°C) on physicochemical quality, functional property, and sensory acceptability of dried onion powder were determined. The results indicated that total color change of Bombay red was not affected by temperature, but Qellafo and Sweet carolin varieties showed an increase in color change as drying temperature increases. Bulk density, shrinkage ratio, and water hydration capacity increased with increasing temperature for all three varieties. The degradation of vitamin C, pyruvic acid, and desired sensory attributes increased with increasing oven drying temperature. All in all, Qellafo dried at 70°C for 5 hr was found to be desirable for production of dehydrated onion powder. The findings of this study will allow the identification of the best of the three commonly grown onion varieties in Ethiopia, and the preferred temperature for production of dried onion with minimal negative effect on physicochemical, functional, nutritional, and sensory properties.

Response of Biomass Development, Essential Oil, and Composition of Plectranthus amboinicus (Lour.) Spreng. to Irrigation Frequency and Harvest Time

A greenhouse experiment was conducted to study the effects of four irrigation intervals (4, 8, 12, and 16 days) and six harvests (2, 4, 6, 8, 10, and 12 months after transplanting) on biomass, essential oil content, and composition of Plectranthus amboinicus (Lour.) Spreng. Fresh weight and essential oil yield decreased with increasing irrigation interval; whereas, essential oil content was stimulated by water stress and increased as the irrigation interval increased. Fresh weight of Plectranthus amboinicus irrigated every 4 days peaked when harvested at 6 months, but essential oil content peaked when irrigated every 16 days and harvested at 2 months after transplantation. On the other hand, essential oil yield peaked when irrigated every 8 days and harvested at 6 months. Thymol, p‐cymene, γ‐terpinene, and β‐caryophyllene were the major compounds, and they peaked at different irrigation intervals and harvest times. This study showed biomass, essential oil content, and yield as well as the major and minor constituents of Plectranthus amboinicus are influenced by irrigation interval and the timing of harvest.