Wheat yellow rust disease caused by Puccinia striiformis f. sp. tritici is one of the most feared and wheat production bottlenecks in the highland areas of Ethiopia. Field experiment was conducted to assess wheat yield losses caused by Puccinia striiformis f. sp. tritici based at optimal frequency of fungicide with wheat varieties for the control of stripe rust at hotspot environments of Meraro and Bekoji, experimental stations in Arsi zone in 2017 main cropping season. Results revealed that there was direct linkage between the disease level and the yield loss in the most common commercially adopted bread wheat varieties. There was varying resistance level among different wheat varieties. The extensively cultivated wheat variety, Wane was found to be most resistant with minimum yield loss of 22.9 to 39.7% followed by Lemu and Danda'a with yield loss of 48.7to 56.5% and43.3 to 57.5% at Bekoji and Meraro respectively. While Kubsa, proved to be the most susceptible wheat variety with maximum yield loss of 91.5 to 96.7% at Bekoji and Meraro respectively. Therefore, it is advisable to use resistant varieties with appropriate fungicides with optimal frequency in order to reduce yield loss and get comparable yield advantage by reducing the incurring of wheat stripe rust in wheat farms.

Wheat is one of Ethiopia's foremost important cereal crops in terms of area coverage and volume produced. However, the production and productivity of wheat is constrained by various biotic and a biotic stresses, among which wheat yellow rust disease caused by Puccinia striiformis f.sp.tritici is the one. Field experiments were conducted to develop integrated wheat yellow rust management strategy based on optimal frequency of fungicide application and wheat varieties combination at hotspot environments of Meraro and Bekoji, Arsi zone, in 2017 main cropping season. Treatments included two different fungicides, Epoxiconazole + Thiophanate-methyl and Propiconazole applied in two frequencies; and four bread wheat cultivars (Kubsa, Danda'a, Lemu and Wane), known for their differential reaction to the disease. Unsprayed controls were also included for comparison purposes. The experiment was laid out in randomized complete block design in factorial arrangement with three replications. Terminal severity levels up to 13%, 37%, 53% and 90% at Bekoji, and 11.67%, 53.3%, 58.33%, 92% at Meraro were recorded on the unsprayed varieties of Wane, Lemu, Danda'a and Kubsa, respectively. Twice application frequency of Epoxiconazole + Thiophanate-methyl resulted in a significant (P<0.01) grain yield increment of up to 95.3%, 76.4%, and 1086.8% at Bekoji and 129.7%, 135.5%, 2883.2% at Meraro on unsprayed plots of Lemu, Danda'a, and Kubsa, respectively. But yield increments as a result of fungicide applications were relatively lower (29.8% and 65.9% at Bekoji and Meraro, respectively) on the resistant variety Wane. Twice application of Epoxiconazole + Thiophanate-methyl at 15 days interval starting from the appearance of disease has proved the most effective in terms of reducing the level of stripe rust, and increasing grain and crop biomass yield. The current findings demonstrate the role fungicides and host resistance may play in effectively managing stripe rust of wheat. However, further research is needed to come up with other management options to sustainable and cost effective manage the disease under different agro-ecological settings.

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This study was conducted at the ethanol plant of Metehara sugar factory, at a laboratory scale, to assess the effect of recycling vinasse into the fermentation process on effluent reduction. Vinasse is an effluent produced from distilleries. The experimental design included vinasse concentrations at 4 dilution rates (0 (control), 20, 35, 50, and 65% of process water) with 2 replicates and 6 responses, as follows: ethanol yield, fermentation efficiency, residual sugar concentration, cell count, cell viability, and calcium oxide content. In this study, the actual operational parameters of the ethanol plant were maintained during the experiment. The result of the experiment indicates that, with up to 20% vinasse recycling, there was no influential impact on the ethanol yield, the fermentation efficiency, the residual sugar concentration, or the calcium oxide content, attributable to the recycling, as compared to the control. Above 20% vinasse recycling, ethanol yield and fermentation efficiency decreased sharply from those of the control. In addition, with 20% vinasse recycling put into practice, the amount of vinasse generated will be reduced by about 19.5% and about 114.2 tons of water will be saved per day. Moreover, the excess amount of vinasse produced by the distillery, which is beyond the handling capacity of bio-compost plant of the distillery, will reduce from 105 to 36.8 tons per day. Therefore, it is possible to recycle vinasse into the fermenter up to 20% on dilution water of Metehara distillery, without causing any impacts on the distillery’s performance.

<i>Physoderma</i> fungal species cause faba bean gall (FBG) which devastates faba bean (<i>Vicia faba</i> L.) in the Ethiopian highlands. In three regions (Amahara, Oromia, and Tigray), the relative importance, distribution, intensity, and association with factors affecting FBG damage were assessed for the 2019 (283 fields) and 2020 (716 fields) main cropping seasons. A logistic regression model was used to associate biophysical factors with FBG incidence and severity. Amhara region has the highest prevalence of FBG (95.7%), followed by Tigray (83.3%), and the Oromia region (54%). Maximum FBG incidence (78.1%) and severity (32.8%) were recorded from Amhara and Tigray areas, respectively. The chocolate spot was most prevalent in West Shewa, Finfinne Special Zone, and North Shewa of the Oromia region. Ascochyta blight was found prevalent in North Shewa, West Shewa, Southwest Shewa of Oromia, and the South Gondar of Amhara. Faba bean rust was detected in all zones except for the South Gonder and North Shewa, and root rot disease was detected in all zones except South Gonder, South Wollo, and North Shewa of Amahara. Crop growth stage, cropping system, altitude, weed density, and fungicide, were all found to affect the incidence and severity of the FBG. Podding and maturity stage, mono-cropping, altitude (>2,400), high weed density, and non-fungicide were found associated with increased disease intensities. However, crop rotation, low weed infestation, and fungicide usage were identified as potential management options to reduce FBG disease.