Parthenium hysterophorus L. is non-native invasive plant species belongs to the family Asteraceae. Currently it is a notorious weed in Ethiopia. Socio-economic impacts as well as the local people's perception towards P. hysterophorus are poorly understood. Thus, the aim of this study was to generate information for a better understanding of the means of dispersal, source introduction and socio-economic impacts, of P. hysterophorus in East shewa and West arsi Zones of the Oromia Regional State of Ethiopia. The study revealed that parthenium was introduced mainly by following vehicles road and railways. This weed grows throughout the year. This results in its fast dispersal. Many mechanisms were assumed by respondents for fast distribution of P. hysterophorus in the study zones. Among these vehicles and wind are the major agents, which proliferate the seeds of the weed. Based on the study it grows in roadsides, grazing land, cropland, village sides and wastelands. Most of respondents also indicated that the weed first appeared on roadside and propagated to other habitats. This finding indicated that the weed high in disturbed habitats. Control methods, which are mostly practiced by local people, were tillage and hand weeding. However, these methods were not an efficient to control the weed distribution; rather it is expanding from time to time since its invasions. P. hysterophorus has a number of socioeconomic impacts that include effect on crop and livestock production, human health, soil fertility and biodiversity. This finding showed that it competes and suppress the growth of crops due its allelopathic nature. Seeds of this weed changes the normal flavor of food when mix with it. It also colonized grazing fields, thus causing animal food scarcity, animals' health defect. This finding also reported that P. hysterophorus has health hazards on human being, which include allergic, skin itching (irritation), cough and hemorrhage. Generally, P. hysterophorus is a foremost troublesome weed and subterfuge threat on agriculture, biodiversity and on human health. Therefore, proper and targeted control methods should be employed to control the further spread and reduce the adverse impacts.

Besides its importance coffee production constraints with number biotic factors of which diseases are major. Coffee is prone to a number of diseases that attack fruits, leaves, stems and roots, and reduce yield and marketability. Major coffee diseases in Ethiopia are Coffee berry diseases (Colletotrichum kahawae), Coffee wilt disease (Gibberella xylarioides) and coffee leaf rust (Himalia vestatrix) however, the rest diseases considered minor. Thread blight of coffee caused by Corticium koleroga is an important disease of Coffee in India. Thread blight diseases in Ethiopian coffee for first time recorded at Gera and Metu agricultural research sub-stations in 1978. However it sporadically occurs between June and September, but becoming important at high land coffee growing areas of southwestern, Ethiopia. Investigations including diagnostic surveys for assessing the disease occurrence, prevalence, incidence and severity was conducted and the sample was brought to Plant Pathology Laboratory of Jimma Agricultural Research Center. The results of study showed that the disease syndrome on detached coffee plants were similar with thread blight of coffee recorded so far and observed at the field. The disease invariably attacks coffee leaves, branches, twigs and berries with characteristic blight symptoms. White fungal threads were seen on the young stems and succulents tender tissues of coffee trees. These threads eventually become dark brown in color grow and spread to cover underside of leaves while coffee berries on infected braches are also completely destroyed leading to total crop failure. The isolation and identification of the causal pathogen from samples of leaves, berries, branches and shoots consistently produced fungal species which may be Corticium koleroga that further proved by pathogenicity tests. The disease mean incidence and severity during first outbreak (2008) at Limmu coffee plantation farm of "Gummer" was 49.02 and 9.8%, respectively. The second reported outbreak of the diseases was from Bebeka coffee estate of "Disadis" farm (2012). Current area wide outbreak at major coffee growing areas of southwest, west and south Ethiopia was in 2014 with mean incidence and severity of 58.44 and 32.59%, respectively, resulting in considerable damages. Among others, climatic factors prolonged rainfall with long period of wet favored the thread blight disease outbreaks implicating the present climate change scenarios are favoring challenging diseases on Arabica coffee production in Ethiopia.

Field survey on parthenium was conducted at East shewa Zone of Oromiya Regional State, Ethiopia during 2008 cropping season.  The objectives of the study was to assess the weed flora composition and plant species that are growing in copetation with parthenium to use those plants as potential biological management options under field condition. Assessment of weed flora composition was carried out in five Kebeles (Farmers Association) of Boset District East Shewa Zone of Oromiya Regional State, Ethiopia. Data on the species composition were recorded and samples of weed flora compositions were collected. The result showed a total of eighty five different herbaceous plant species that were collected and recorded in 63 genera and 24 families. Poaceae (21), Asteraceae (11), Fabaceae (7) and Convolvulaceae (7) were by far the richest taxa and accounted together (55 %) of the entire flora of the study area. The major plant species having higher dominance value were Parthenium hysterophorus (25.6), Cassia tora (6.07), Argemone mexicana (5.83), Xanthium strumarium (4.53), Digitaria abyssinica (3.02) and Cyperus rotundus (2.86). Similarity index values of the species composition among different kebeles ranged from 65% to 78% which indicating that weed species compositions in these locations were similar. The diversity and evenness of species declined with increasing spread of parthenium which suggests negative influence that parthenium had on the status of species diversity in the studied area. In conclusion the selected plant species that were found competitive with parthenium based on their abundance and dominance values were Argemone mexicana, Cassia tora, and Xanthium strumarium which were suggested for detailed competition experiment in order to determine their competitiveness with P. hysterophorus and will be used for biological management of it.

It is essential to reduce coffee yield losses due to coffee wilt disease (CWD) in the country through the development and use of genetically resistant coffee varieties to increase and consistently supply Arabica coffee to the fast growing coffee industry. The soil-borne nature of the pathogen and perennial character of coffee have made management of coffee wilt disease difficult through the conventional control approach of 'uproot and burn infected trees at the spot'. Therefore, longer-term prospects of successful management of coffee wilt disease depend principally upon employing resistant coffee cultivars. With this objective laboratory and field evaluations were conducted to screen some coffee genotypes against coffee wilt disease. Disease severity or mean percent seedling death ranged from 0.00 to 89.96 %. The result showed in lowest seedling death rate, long incubation period and high field survival rate of most accessions indicating resistant reaction to coffee wilt disease. Thus present experiment implied that the potential of obtaining coffee wilt disease resistant coffee variety from these accessions provided that they have other desirable traits like resistance to major coffee diseases, high yield and improved quality.