Crop Protection
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Item ASSESSMENT OF MANGO YIELD LOSS AND FRUIT FLY (DIPTERA, TEPHRITIDAE) MANAGEMENT PRACTICES OF MANGO PRODUCING FARMERS IN ARBAMINCH ZURIA WOREDA, ETHIOPIA(Hawassa University College of Agriculture, 2023) ESSEYNESH ALEMAYEHU FENTAHUNMango (Mangifera indica L.) is a valuable food and cash crop that contributes to agricultural development agents. This study was conducted to assess mango fruit yield loss due to fruit flies (Diptera, Tephritidae) and management approaches by farmers in Arbaminch, Zuria Woreda. Three administrative kebeles, viz., "Chano mile," "Lante," and "Kolla shele," were purposively selected from the Arbaminch Zuria Woreda. Both survey and assessments were collected. Sixty respondents were interviewed using semi-structured questionnaires. Mango variety, mango pests and their economic importance, abundance, infestation, yield loss estimation, management practices applied for fruit flies and farmers’ willingness to pay for the best management options were assessed. The results were analyzed using SPSS software and presented using descriptive statistics; and the variables were tested by chi-square test. Farmers in Arbaminch Zuria produced five types of mango varieties, with local mango varieties being the most common. All the respondent farmers (100%) had the local mango variety. Common mango fruit pests like fruit flies, white mango scales, mealybug, grivet monkeys, speckled birds, and weaver ants as an indirect pest which may interfere with natural enemies were recognized. The fruit fly species Bactrocera invadens was trapped in the field with the abundance of 43 flies per trap per day (FTD). Fruit flies caused 94.28±10.21 Kg and 29.84% of loss in fruit yield per tree. The mean monetary loss value was estimated to 471,412.3±51010.9 birr/ha/year. The highest infestation was recorded in the peak harvest time (February) which was 40.78%. To overcome the fruit fly damage, mango producers applied different management methods. Of these methods, Methyl Eugenol trapping, field sanitation, burying infested fruits, and smoking the field were the most common. It was concluded that mango fruit flies are the most economically important insect pests of mango in the Arbaminch Zuria Woreda. The study recommends the evaluation and release of less susceptible mango varieties to fruit fly infestation, white mango scale, and other pests and diseases, evaluate the farmers’ practices. And new methods of management to develop a holistic integrated pest management systemItem ASSESSMENT OF WEED SPECIES COMPOSITION AND THEIR MANAGEMENT PRACTICES IN ONIONAND EFFECT OFDIFFERENT WEED CONTROL METHODS IN ONION (Allium cepaL.)IN THE CENTRAL RIFT VALLEY OF ETHIOPIA(Hawassa University College of Agriculture, 2019) FEYISA BEKELE JIMAFarmers have lack of awareness on weed problem on the crop and under take only manual weeding option to control those weeds in their fields. The study identified weed species composition and their management practices in onion (Allium cepa L.) fields of Adami Tulu, Dugda, Lume, and Around Adama woradas, Central Rift Valley of Ethiopia. In addition the effect of different weed control methods in onion were evaluated in Meki woreda during 2017/2018 under irrigation. Primary data were collected from 200 individual farmers using structured questionnaires, face to face interview. Secondary data were collected from different literatures and reports, and analyzed using descriptive statistics, using SPSS version 20. Weed species compositions were determined in a quadrat count of 0.5m2 using systematic sampling techniques to obtain representative sample in the fields. The identified individual weed specieswere analyzed using quantitative means. Identified most problematic weed families wereAsteraceae (16 spp.), Poaceae (10 spp.), Solonaceae (2 spp.),Cyperaceae (2spp.)in descending order of 1st, 2nd, 3rdand4rd abundant weed families, respectively.The experiment was contained 13 different weed control treatments and laid down in randomized complete block design with four replicates. Collected data were analyzed using SAS version 9.0. The weed density varied significantly with the treatments (P<0.05). At 60 DAT the lowest weed density (41.875/m2) was recorded under HW3WAT followed by Oxyflourfen at 0.5L/ha + HW6WAT. At harvest the lowest weed density (30.875g/m2) was obtained under Oxyflourfen at 0.5L/ha+HW6WAT. The lowest weed dry weight was recorded from Pendimethalin at 1.5L/ha+HW9WAT (293.27g/m2). The highest weed controlefficiency(82.15%) was recorded under Pendimethalinat 1.5L/ha+HW9WAT followed by Oxyflourfen at 0.5L/ha+HW9WAT (80.48%) after weed free plot.The maximum plant height (43.47cm) was recorded in weed free plot followed by Oxyflourfen at 0.5L/ha+HW3WAT (40.68cm). But the number of leaves per plant has shown no significant difference with respect to different treatments (P>0.05). Maximum bulb diameter, bulb weight, bulb size (3.51cm, 122.58g, 73.25ml, 29.62ton/ha) were recorded respectively from weed free plot, which were statistically non-significant from Oxyflourfen at 0.5L/ha+HW9WAT). The lowest loss in yield (0.03%) was recorded in weed free check followed by plot treated with oxyflourfen at rate of the 0.5 L/ha + HW6WAT (6.8%) as compared to the highest yield obtained in plot treated with oxyflourfen at rate of the 0.5 L/ha + HW9WAT. Weed free check plot resulted in higher cost of protection and gross return but lower in net return and benefit: Cost ratio, whereas Oxyflourfen at 0.5L/ha and pendimethalin at 1.5L/ha showed highest Benefit: Cost ratio (20.34 and 14.65) respectively. The study showed that using herbicides alone or in combination with hand weeding is highly profitable than using hand weeding alone. Future studies on the use of herbicides with different rates and combinations with other methods, critical period of weed-control and more survey works in different onion production agro-ecologies are recommended.Item CHICKPEA WILT (FUSARIUM OXYSPORUM F. SP. CICERIS) INTENSITY IN NORTH SHOA, ETHIOPIA, AND EVALUATION OF CHICKPEA GENOTYPES AGAINST THE PATHOGEN(Hawassa University College of Agriculture, 2024) Kalkidan WuduChickpea (Cicer arietinum L) is an important pulse crop in Ethiopia. However, chickpea Fusarium wilt (CFW) is the major constraint on its production. Thus, this study was designed with the following objectives: to assess the prevalence, incidence, and association of biophysical factors with CFW in North Shoa Ethiopia and evaluate chickpea genotypes against the pathogen. For this purpose, a field survey was conducted during the 2022 main growing season. Descriptive statistics and logistic regression model were used to analyze association of the disease with different biophysical factors. Fungal isolation was done out by placing small bits of infected root on PDA at Hawassa University Crop Protection Laboratory. Colony characteristic of the fungus were studied on PDA. The spores were obtained by growing the fungal pure culture on SNA. The pathogen was morphologically identified using appropriate identification manual. Sixteen chickpea genotypes were screened for their reaction to CFW under a lath house condition. The survey results revealed that CFW was prevalent in all the surveyed areas, with different levels of incidence. A higher CFW incidence (43.2%) was recorded at Siyadebrna-wayu district, while a lower (34.8%) CFW incidence was recorded at Ensaro district. High mean CFW incidence was recorded on chickpea sown late August (39.2), desi-type chickpea (39.7), fields previously sown with legumes (43.9),lower altitudes (40.3), pod setting stage (41.2) and weedy fields (45.8%). In the model, crop growth stage, district, previous crop, and weeding practice were significantly associated with FOC incidence. The highest (>38%) wilt incidence was highly associated with weedy fields. The fungal mycelia were white in color. The macro conidia were straight to slightly curve with three septa. While the micro conidia were oval and no septation, Based on these, the pathogen was identified as F. oxysporum f. sp. ciceris (FOC). Three chickpea genotypes (DZ-2012-CK-0312 followed by FLIP12-138c and ICCMABCD-21) were moderately resistant, while nine chickpea genotypes were susceptible. The result of the current study confirmed that CFW was highly prevalent in the study areas. Thus, designing effective CFW management options by targeting important biophysical factors that influence disease pressure and using chickpea varieties that have some degree of resistance to the disease is essential. It would be better to repeat the late house experiment for one or two times and further tests under field conditions to come up with sound recommendations.Item DETERMINATION OF CRITICAL PERIOD OF WEED CONTROL ON GINGER (Zingiber officinale Roscoe) AT SELAM, SOUTH WEST ETHIOPIA(Hawassa University College of Agriculture, 2024) MULUKEN ASFAW WOLDEGinger is an important spice and cash crop in Ethiopia. However, its production is constrained by different abiotic and biotic factors; weed is one of the most important biotic factors which reduces yield of ginger. Therefore, this study was conducted in 2023 main cropping season at Yeki, South Western Ethiopia to determine the critical period of weed competition and yield loss. The trial had twenty treatments in two sets, namely weedy set and weed-free set, each sets comprising weed competition durations of 15, 30, 45, 60, 75, 90, 105, 120 and 135 days after crop emergence and weedy control as well as weed-free plot throughout crop life cycle. The trial was laid out as a randomized complete block design with three replications and the treatments were assigned randomly to experimental units within a block. The weed and crop data were collected and subjected to analysis of variance by using SAS software. The most dominant species was Bidens pilosa L. (Asteraceae family) with density and relative density of 73 m -2 and 18.4%, respectively. Weed density, weed dry biomass, yield components and yield of ginger were significantly affected by weed competition durations. Uncontrolled weed growth reduced the yield of ginger by 93%. The beginning of CPWC (Critical period of weed control) based on 10% AYL (acceptable yield loss level) occurred at 180 GDD (Growth degree days), which was corresponded to 26 DAE (Days after emergence). The end of the CPWC at 10% AYL occurred by 1150 GDD or 143 DAE. To prevent more than 10% yield loss, the efficient weed contr ol period for ginger at Selam area could be accomplished by keeping the crop weed free between 26 to 143 DAE. Further research in different physiographic, edaphic and climatic conditions is recommended.Item ECOLOGY AND MANAGEMENT OF BITING ANT, Tetramorium aculeatum MAYR (HYMENOPTERA: FORMICIDAE) IN COFFEE, Coffea arabica L. IN SOUTHWESTERN ETHIOPIA(Hawassa University College of Agriculture, 2019) SISAY KIDANU DEMMIREWBiting ant, Tetramorium aculeatum Mayr (Hymenoptera: Formicidae) is an important pest in coffee that affects farming activities in Southwestern Ethiopia. The objectives of this study were to assess farmers’ knowledge and pest management practices of biting ant understand the ecology of biting ant in Southwestern Ethiopia, and evaluate the efficacy and potential of some insecticides. Survey was conducted on 180 coffee farmers in 12 districts. Spatial distribution of biting ant was studied in eight coffee farms and analyzed by semivariance using geostatistics (GS+10). Nine insecticides treatments were evaluated both under ex-situ and in-situ conditions in CRD and RCBD designs, analyzed by analysis of variance. Most of the farmers interviewed (58.9%) recognize the problems of biting ant in coffee and some (23.3%) of them are knew this ant for about ten years. Significant variations were observed in the levels of infestation and abundance of the biting ant in different ecology of coffee producing districts and production systems. Lower altitudes and private coffee plantations had higher number of nests. The biting ants within coffee plant are aggregate on the tree. The semivariogram of the biting ant characterized with localized discontinuity and long range correlation in some coffee farms and vice versa in the others indicating spatial dependence of biting ant nests between samples pairs. The spatial distribution trends of the nest in the field showed aggregated along the center and in some farms near corners and declined from there across to the inner field. Under the ex situ evaluation, all the insecticide treatments caused significantly (p≤0.01) higher mortality (100%) of biting ants and caused complete mortality within 24 hours. Under field condition the insecticides showed significant variations on percent of evacuated nests. However, the two botanical insecticides, oxymatrine and nimbicidine, performed significantly (p≤0.01) as par with the other tested insecticides up to 18th day after application. On the other hand, deltamethrin 2.5% at the rate of 0.75ml/l of water caused significantly highest percent of evacuated nests and less number of newly constructed nests of biting ant (0.2) after thirty days of application. Generally deltametrin 2.5% at 0.75ml/l can be used for heavily infested farms where pruning and manually destructing the nest difficult and the future it is important to conduct insecticide evaluation with additional botanical based insecticides, and also undertake residual effect analysis of deltamethrin insecticide in coffee environment.Item EFFECT OF INTERCROPPING MAIZE VARIETIES WITH DIFFERENT CROPS ON FUNGAL CONTAMINATION OF MAIZE GRAIN IN DOREBAFANA WOREDA SIDAMA REGION(Hawassa University College of Agriculture, 2023) TESHALE TAFESSE LINTAMOMaize (Zea mays) is attacked by many diseases in the field as well as in the storage. Fungi are among the principal causes of deterioration and yield loss on farmers’ maize. The present study was aimed to identify the effect of different crop combinations in the intercropping systems and maize varieties on fungal contamination of maize grain. The experiment was conducted at dorebafana woreda of Sidama region at rukesa suke kebele and the laboratory analysis was conducted at Hawassa University, College of Agriculture, Plant Protection Laboratory. Three maize varieties (Limu, Kurtu and BH 540) and four cropping systems (Maize sole, Maize with haricot bean intercropping, Maize with mung bean intercropping, maize with sweet potato intercropping) were the treatments. The experiment was laid using completely randomized block design (RCBD) with three replications. For each treatment a sample of 100 seeds were tested for fungal contamination using the blotter technique in the laboratory. A total of six fungal genera consisting of nine species of fungi were isolated from maize grains collected from the experimental field. Fusarium sppwere the most frequently isolated ones followed by Aspergillus spp. The fungal contaminations of maize grains were significantly different (p<0.05) between sol cropping and intercropping treatments. The sol cropping had higher fungal contamination level compared to intercropping treatments. On the other hand, i ntercropping maize with haricot bean has resulted in the lowest fungal contamination followed by intercropping maize with mung bean. Fusarium spp had resulted highest contamination level followed by Aspergillus spp, Penicillium spp, Alternaria spp, Trichoderma spp, and Rhizopus sp. Low level of fungal frequency was recorded on limu maize variety. Whereas the variety kurtu had the highest level of fungal contamination. The result of the present study revealed that maize cropping system affects the level of fungal contamination. In the present study it is also seen that maize varieties tested vary in their resistance to fungal contamination. Thus, good agronomic practices like intercropping and variety selection can play determinant role in reduction of fungal contamination in maize grain. Based on the finding of present study, intercropping maize with haricot bean and variety limu can be used to reduce effect of maize contamination with fungi.Item EFFECT OF VARIETY AND FUNGICIDE FREQUENCY ON THE MANAGEMENT OF TOMATO LATE BLIGHT (Phytophthora infestans (MONT) DE BARY) IN BOMBE WOREDA, WOLAITA ZONE, SNNPR, ETHIOPIA(Hawassa University College of Agriculture, 2020) DINKINESH DESTA ANSHEBODiseases are the major constraints that limit production of tomato in Ethiopia. Late blight is a very severe disease in most tomato growing regions, including in Wolaita zone, where information on disease management options through integration of varieties and fungicide applications are poor. Aim of the present study was therefore, to determine frequency of fungicide spray with respect to host resistance level on the management of late blight of tomato. A field experiment was conducted at Frwocha kebele in Boloso Bombe Woreda during 2019 cropping season. The experiment was laid using RCBD in factorial arrangements with three replications. The treatments consisted of four foliar spray frequencies, and three tomato varieties (Melkasalsa, Metadel and ARPTd2). Important parameters collected were incidence and severity of late blight, and growth and yield related traits of tomato. Significant variations were observed among varieties in reducing late blight of tomato and increasing the fruit yield. The highest late blight severity and AUDPC (43.2 and 629.81, respectively) were recorded from variety Melkaslsa, and the lowest (32.59 and 441.61, respectively) were recorded from variety ARPTd2. Interaction of varieties and fungicide spray frequencies did not show significant difference on most components of late blight epidemics, crop growth and yield related parameters. However, significance differences were observed on marketable and total fruit yield. The maximum marketable (61.70) and total fruit yield (67.30) were recorded from plots treated with three and two time sprayed on ARPD2 tomato variety, respectively, while the lowest marketable (24.06) and total fruit yield (35.43) were recorded from unsprayed plots of Melkasalsa and Metadel varieties, respectively. Correspondingly, the highest disease progress rate of (0.09) was obtained in unsprayed plot of the variety Melkasalsa; however the lowest disease progress rate of (0.04) was recorded from the plots of ARPTd2 and Metadel variety treated with Ridomil four times at 7 days interval. Fruit yield loss of up to 47.04% was calculated on unsprayed plots as compared to highly treated plots. On the other hand, marginal analysis indicates that the highest 87.94% marginal rate of return in comparison with unsprayed plots was obtained where ridomil sprayed two times on ARPTd2 variety as compared to other spray frequencies. In conclusion, integrations of varieties and two times foliar spray of ridomil on ARPTd2 variety were found to be an effective treatment in reducing tomato late blight epidemics and increasing fruit yield. Moreover, ARPTd2 variety appears to have comparative resistance to late blight and is a promising tomato variety. However, further investigation should be carried out for developing concrete recommendation for late blight management options through integration of varieties and fungicide spray frequency that may contribute to sustainability by stabilizing tomato production in the country.Item EFFECTS OF FORAGE LEGUME INTERCROPPING AND FERTILIZER APPLICATION ON FUNGAL CONTAMINATION OF MAIZE (Zea mays) GRAIN IN DORA BAFANO WOREDA SIDAMA REGION(Hawassa University College of Agriculture, 2022) ASMAMAW SISAY ASCHENAKIMaize (Zea mays) is one of the most important cereal crops grown throughout the world. It serves as staple food for millions of people and a source of feed for animals. The crop gives 365 Kcal of energy per 100 g of grain. However, maize is reported as the most susceptible crop to fungi contamination. Hence, management of grain contaminating fungi is vital to ensure sustainable and safe food and feed production. In the present study, a field experiment was conducted to evaluate the effects of forage legume intercropping and fertilizer application on fungi contamination of maize grains. The experiment was done using a randomized complete block Design with 10 treatments replicate trice. The experiment employed factorial combinations of five cropping systems and two fertilizer (with ad without) application. Isolation and identification of fungi from the maize grain and soil was done. A total of 6 fungal genera consisting of 12 species were isolated and identified by their morphological characteristics. Fusarium species were the most frequently isolate, followed by Aspergillus and Pencilium spp. Both forage legume intercropping and fertilizer application significantly reduced the frequency of grain contaminating fungi. The frequency of fungi contamination observed to reduce from 17.66 to 8.66 % in case of Fusarium verticillioides when intercropped with cowpea in double rows. Similarly, when fertilizer is applied, the frequency of Fusarium verticillioides was reduced from 14.6 to 9.0 %. The population density (CFUg -1 ) of Aspergillus, Fusarium, Penicilliu, Mucor and Trichoderama species in the soil were significantly reduced when maize was intercropped with forage legume. The finding revealed that intercropping of maize with forage legume and application of fertilizer highly reduce maize grain contaminating fungi.Item Evaluation of Selected Bio-rational and Synthetic Ins ecticides against Cabbage Aphid (Brevicoryne brassicae) (Homoptera: Aphididae) on Cabbage in the Central Rift Valley of Ethiopia(Hawassa University College of Agriculture, 2021) ETENESH ADNEW ALOTOCabbage (Brassica oleracea L. var. capita) is one of the most popular food crops and grows well in many parts of Ethiopia. One of the constraints for the production and use of head cabbage is cabbage aphid (Brevicoryne brassicae (L.)) which damages cabbage from seedling to final growth (head formation) stage. This study aimed to evaluate the efficacy of selected bio rationales and to investigate the use of effective bio -rationales in rotation with synthetic insecticides against cabbage aphids under field conditions. Field experiments were conducted in two locations at Batu, Eastern Shewa of Oromia Regional state, and Hawassa, Sidama Regional state during the dry season of 2019/2020. Two separate expe riments were laid out in a randomized complete block design (RCBD) with four replications. The first experiment was an efficacy test of bio-rational insecticides (mixture of natural plant extracts and phytoenzyme, Spinosad, Millettia ferruginea, Nimbecidine, Sophora flavescens plant extract 25% + emamectin benzoate 1% SL, dimethoate 40% EC (as a standard check), and untreated plots). The second experiment was an efficacy test of selected bio-rational and synthetic insecticides in rotation (Nimbecidine + dim ethoate 40% EC, Sophora flavescens plant extract 25% + emamectin benzoate 1% SL+ dimethoate 40% EC, mixture of natural plant extracts and phytoenzyme + dimethoate 40% EC, Spinosad+ dimethoate 40% EC, Milletia ferruginea+ dimethoate 40% EC, dimethoate 40% EC (as a standard check) and untreated plots). The results showed that all biorational insecticides reduced aphid population when compared with the untreated plots. Spinosad, Nimbecidine, and a mixture of natural plant extracts and phytoenzyme effectively controlled aphids on cabbage and were comparable to the standard check (dimethoate 40% EC) and gave higher yield. The maximum total yield of head cabbage was obtained from dimethoate 40% EC treated plots, 57.6 tons/ha and 58.4 tons/ha, followed by Spinosad 55.4 and 56.4 tons/ ha at Hawassa and Batu, respectively; Nimbecidine 51.4 tons/ ha at Hawassa which were not significantly (P<0.05) different from dimethoate 40% EC treatment. In rotation applications of Spinosad, Nimbecidine, and a mixture of natural plant extracts and phytoenzyme with dimethoate 40% EC effectively controlled aphids on cabbage and were comparable with the sole application of standard insecticide (dimethoate 40% EC). The highest total yield of head cabbage was obtained from dimethoate 40% EC treated plots, 60.6 tons/ ha at Hawassa and 61.2 tons/ ha at Batu, and was not significantly different from Spinosad + dimethoate 40% EC treatment in both locations and Nimbecidine+ dimethoate 40% EC at Hawassa. The lowest yield (12.8, 12.4 ton/ha) was obtained from the untreated plots. Thus, Spinosad, Nimbecidine, and mixture of natural plant extracts and phytoenzyme as a sole application or Spinosad, Nimbecidine, and mixture of natural plant extracts, and phytoenzyme in rotation with dimethoate 40% EC can be used to control cabbage aphids on cabbage.Item Evaluation of Selected Bio-rational and Synthetic Insecticides Against Onion Thrips (Thrips tabaci L.) (Thysanoptera: Thripidae) on Onion (Allium cepa L.) in the Central Rift Valley of Ethiopia(Hawassa University College of Agriculture, 2021) TAMENE GETAHUN BARISOOnion thrips, Thrips tabaci (Thysanoptera: Thripidae) is a key insect pest of onion. Onion growers at Meki and Batu locations rely on synthetic insecticides to control onion thrips. This practice encourages the development of insecticide resistance. Therefore, the search for alternative measures has become increasingly important. The present study was designed to evaluate the efficacy of selected bio-rational insecticides and the efficacy of selected synthetic and bio-rational insecticides in rotation against onion thrips. Field experiments were conducted in two locations at Meki and Batu, Eastern Shewa of Oromiya Regional state of Ethiopia during the dry season of 2019/2020. Two experiments were laid out in a randomized complete block design (RCBD) with four replications. Experiment one evaluated the efficacy of bio-rational insecticides (nimbecidine, spinosad, spinetoram, mixture of natural plant extracts and phytoenzyme, Sophora flavescens plant extract 25% + emamectin benzoate 1% SL, Milletia ferrugienea, profenofos (as a standard check) and untreated plots). Experiment two evaluated efficacy of selected bio-rational and synthetic insecticides in rotation (nimbecidine + profenofos, nimbecidine + imidacloprid, mixture of natural plant extracts and phytoenzyme + profenofos, mixture of natural plant extracts and phytoenzyme + imidacloprid, imidacloprid, profenofos (as a standard check) and untreated plots). The study showed that all the biorational insecticides reduced thrips population when compared with the untreated plots. Spinosad, nimbecidine and mixture of natural plant extracts and phytoenzyme effectively controlled thrips on onion and were comparable to the standard check insecticide (profenofos) and gave significantly higher yield than the untreated. Nimbecidine + profenofos and mixture of natural plant extracts and phytoenzyme + profenofos in rotation treatments effectively controlled thrips on onion and were comparable with the standard insecticide (profenofos). The highest yield (29.75, 31.22 ton/ha) was obtained from nimbecidine + profenofos in rotation treatment and the lowest (13.93, 14.36 ton/ha) from the untreated. Thus, spinosad, nimbecidine and mixture of natural plant extracts and phytoenzyme as a sole application or nimbecidine + profenofos and mixture of natural plant extracts and phytoenzyme + profenofos in rotation can be used to control onion thrips on onionItem EVALUATION OF WEED MANAGEMENT PRACTICES ON MUNG BEAN (Vigna radiata L.) YIELD AND YIELD COMPONENTS AT TEPPI, SOUTH WEST ETHIOPIA.(Hawassa University College of Agriculture, 2023) MULUKEN ASMAMAWMung bean is characterized by fast growth, low water requirement, and excellent soil fertility enhancement through nitrogen fixation. The productivity of mung beans is decreased by weeds, diseases, and insect pests. Weed competition is among the most important factors responsible for the low yield of mung bean by as much as 87%. Therefore, this study was initiated to evaluate the effect of weed management practices on yield and yield components of mung bean (Vigna radiata L.). Nine control options (One-hand weeding at 4 weeks after sowing, complete weed control, No-weed control, Haloxyfop-R-methyl ester at 0.3, 0.6, and 0.3 kg ai ha⁻¹ + One-Hand weeding at 4 weeks after sowing, pendimethalin at 1, 1.5 and 1 kg ai ha⁻¹ + One-Hand weeding at 4 weeks after sowing) were compared in randomized complete block design in three replications. The application of herbicides and the weeding practices significantly reduced the broadleaf, sedge, and grass weeds. The highest grain yield (0.98 ton ha⁻¹), total dry biomass (2.82-ton ha⁻¹), and plant height (43.76 cm) were obtained in complete weed control followed by application of pendimethalin at 1.5 kg ai ha⁻¹ (0.92 ton ha⁻¹), total dry biomass (2.78 ton ha⁻¹), plant height (50.03 cm). The lowest grain yield (0.36 ton ha⁻¹), total dry biomass (1.59-ton ha⁻¹), and plant height (64.63 cm) were recorded from the No-weed control plot. The highest number of pods per plant, number of seeds per pod, and weight of a hundred seeds were recorded in complete weed control and application of pendimethalin at 1.5 kg ai ha⁻¹. The results indicated that complete weed control and/or control with pendimethalin at 1.5 kg ai ha⁻¹ were the best management practices to maximize economic benefit. Thus, we recommend using the applications of one of the two weed control methods for the management of weeds in mung bean in Teppi, South West Ethiopia, and locations with similar agroecologies of Teppi.Item INVESTIGATION OF ANTI MICROBIAL ACTIVITY OF TRADITIONAL BOTANICAL PESTICIDES COLLECTED FROM SIDAMA AREA, SOUTHERN ETHIOPIA(Hawassa University College of Agriculture, 2022) Getachew Binchamo AnnoIndigenous knowledge and systems of crop protection are at risk of extinction today because of the rapidly changing natural environments and cultural shifts at global scale. Many traditional pest control practices are disappearing because of introduction of foreign technologies like synthetic pesticides that assure short-term solutions to the problems. The aim of the present study was therefore, to identify the potential of botanical used by farmers in Sidama region, and investigate their antimicrobial activities against some plant pathogens. Information on traditional botanicals pesticides used for crop pests control was collected through observation, key informant interview, questionnaire, and group discussions. The antimicrobial activities of the common botanicals in the study area were investigated using filter paper disc and agar well diffusion method following standard procedure. The bioactive compounds from leaves of 16 botanicals were extracted with 95% ethanol, and the phytochemical tests were conducted. The result revealed that farmers in the study area have different ethnobotanical experience in their neighbourhood. Various plants belonging to different families were valued for pesticide activities. The botanically-derived pesticides were perceived to be affordable, effective, available, safe and dependable. However, estimating the proportion/ concentration of botanicals to be used for pest control where mentioned as a critical challenge. The ethanolic extract of Cordia africana (18.30mm) showed the maximum inhibition zone against Fusarium vertecelloides while the minimum antibacterial activity was observed by Eucalyptus globules extract (9.43mm) against Ralstonia solanacearum as compared with other botanicals included in the current work. Our investigation showed that the botanicals contain phenols, tannins, glycosides, flavonoids, saponins and steroids. The present work revealed that botanicals in the study area have potential to be used for crop pest control. In order to exploit this potential; standardized techniques of preparation, bio-safety and environmental guidelines are required.Item PHENOTYPIC AND GENOTYPIC CHARACTERIZATION OF THE WHEAT STEM RUST PATHOGEN (Puccinia graminis f.sp. tritici) AND VARIETIES’ REACTION TO MAJOR STEM RUST RACES IN ETHIOPIA(Hawassa University College of Agriculture, 2019) TSEGA’AB TESFAYE WANOREStem rust caused by Puccinia graminis f.sp. tritici (Pgt) is one of the most important diseases of wheat (Triticum aestivum) across the globe. Because of the sudden changes in stem rust race patterns, commercial varieties are becoming vulnerable globally at large and particularly in Ethiopia. The objectives of this study were to i) assess the distribution of wheat stem rust across selected major wheat producing regions of Ethiopia, ii) study population diversity of pgt races and iii) identify physiological race and the reaction of wheat genotypes to major races of the pathogen. For this purpose, a total of 464 wheat fields were surveyed in eight zones and 37 wheat producing districts of Amhara and Oromia regional states of Ethiopia. Besides, 60 disease samples were collected for race analyses using 20 differentials in a greenhouse trial and molecular diversity of the pathogen was studied using custom PgtSNP 3.0K chip. The reaction of 75 wheat genotypes and 1 universal susceptible check to major races of the pathogen was also evaluated in the greenhouse. Stem rust prevalence in the surveyed areas ranged from 0 to 100%, while disease incidences and severity varied between 0 and 25% and 0 and 11.5%, respectively. Greenhouse trials involving 20 differential cultivars resulted in the identification of three Pgt races (TKTTF, TTKSK and TTRTF) among the collected stem rust samples. Of these, TTRTF has not been previously reported in Ethiopia and hence, this is the first report of TTRTF in Ethiopia. Race TKTTF, also known as “Digalu race”, was the most frequent (75% frequency) of all the races of Pgt. The remaining two races TTKSK (Ug-99) and TTRTF were detected with frequencies of 4.16 and 22.91%, respectively. Eighty five percent of the stem rust resistance genes (Sr5, Sr21, Sr9e, Sr7b, Sr6 Sr8a, Sr9g, Sr9b, Sr17, Sr9a, Sr9d, Sr10, Sr38 and McN) were ineffective to all the races detected and 30% of the resistance genes were found to be effective to one or more of the races identified. However, in the present study only the differential host carrying Sr24 was effective to all the races identified in the study areas. The presence of the three Pgt races was also confirmed by molecular study, which categorized the isolates into three clades as I, IVB and IIIB for TTKSK, TKTTF and TTRTF, respectively. The resistance screening trial revelaed that five durum wheat genotypes namely Bichena, Tob-6, Assasa, Kokate and DW/NVT-LMA and six bread wheat genotypes namely, Sulla, Hidase, Wane, 36ESWY, ETBW 8459 and 36ESWYT were resistant against all the races at the seedling stage. These resistant genotypes can be used in wheat improvement programs after being checked under field condition for their adult stage resistance.Item SURVEY ON FUNGAL AND AFLATOXIN CONTAMINATION OF STORED MAIZE (Zea mays) GRAINS IN SOUTHERN ETHIOPIA(Hawassa University College of Agriculture, 2022) MEMHIRU MEKISO MADEBOMaize (Zea mays L.) is attacked by more than sixty diseases and a number of species of insect pests and microorganisms in the field as well as in the storage. Fungi are among the principal causes of deterioration and yield loss on farmers’ maize during the storage period. Among the storage fungal pathogens Fusarium, Aspergillus, and Penicillium are the most predominant species attacked maize grain and resulting in production of harmful products of Mycotoxins. The study was conducted at the Hawassa University College of Agriculture in plant pathology laboratory. The study was aimed to study effect of storage duration and storage type on fungal contamination and assessments of aflatoxin contamination of maize grains in southern Ethiopia . A total of 165 Maize grains samples were collected from different storage type and storage duration in southern Ethiopia, in 2019/2020. A total of seven fungal genera consisting of twenty one species of fungi were isolated from maize grain by using morphological characterstics; Fusarium spp. were most frequently isolated, followed by Aspergillus spp.The fungal contaminations of maize grains were significantly different (p<0.05) increased with storage periods. At the last six months of storage, the contamination of the Fungal isolates revealed that Fusarium spp had the highest contamination of 43.6% followed by Aspergillus spp, 28.6%, then Penicillium spp 5.27%, Alternaria spp 4.12%, Rhizopus spp 3.08%,Tricoderma spp 1.65% while the least contamination of 1.22%, was Cladosporium spp. The highest contamination of Fusarium spp (44.79%) and Aspergillus spp (24.98) were recorded in storage basket whereas the minimum contamination of Fusarium spp (35 %) and Aspergillus spp (15.5%) were obtained from plastic storage. As a result of this research, the Plastic container storage was determined to be more appropriate for protecting the stored maize grains from fungal attack during the storage periods and the stored grains have low fungal contamination until initial t o six months. Therefore, storage Basket, storage Crips, storage Sacks and Gombisa storages were inadequate for protecting stored maize from fungal attacks. Total aflatoxins has quantified from the maize samples collected from different maize growing areas in southern Ethiopia by using Enzyme Linked Immune Assay (ELISA) Kit. The result reveal that the mean 32(66.7%) of 48 maize grain sample were positive for aflatoxin contamination with levels of aflatoxin concentration ranging from 0.21-18.06µg/kg. The average aflatoxin concentrations detected in the present study were below the US Food and Drug Administration (FDA), the World Health Organization (WHO) maximum limit of total aflatoxin 20μg/kg. The EU has maximum limit of 4 μg kg−1 total aflatoxin in cereal for direct human consumption. Thus, most of the samples contaminated with aflatoxins in this study are not suitable for human consumption by the EU standards.Item SURVEY OF CHICKPEA WILT IN NORTH SHEWA ZONE, NORTH EASTERN ETHIOPIA AND EVALUATION OF CHICKPEA VARIETIES AGAINST FUSARIUM WILT (Fusarium oxysporum f. sp. ciceris) ATSIYA DEBRNA WAYU WOREDA(Hawassa University College of Agriculture, 2020) BASAZIN DEMISSChickpea is an important source of human food and animal feed and is grown in many parts of the world including Ethiopia. Chickpea production is constrained by several biotic and abiotic factors. Chickpea wilt disease is among the major constrains of chickpea in Ethiopia. Presently the information on the status of Chickpea wilts disease and reaction of chickpea varieties to the disease in the study area is lacking. Therefore the present study was conducted with the main objective of determining the status of Chickpea wilt disease at selected woredas of North Shewa Zone, North Eastern Ethiopia and to evaluate chickpea varieties for their reaction against the disease. The survey was conducted at chickpea potential production woredas (Moretna Jiru, Ensaro, Mojana Wedera and Siyadebrna Wayu) during 2018/2019 cropping season. The field data (disease incidence and prevalence)were collected by using simple random sampling technique from farmers’ and research fields. The pathogen was isolated from chickpea plants showing typical wilting symptoms. Pathogenicityof Fusarium oxysporum f.sp.ciceris was confirmed by root dipping inoculation technique in pots under plastic greenhouse condition by using susceptible variety kassech. Seven chickpea varieties were evaluated against Fusarium wilt reaction at Siyadebrna Wayu woredas naturally infested field. The design used for this experiment was randomized complete block design (RCBD) under field condition with three replications. Both incidence and severity data was taken from the field experiment. Chickpea Fusarium wilt incidence was recorded three weeks after sowing while severity data was taken for four consecutive weeks starting from three weeks after sowing. Disease prevalence of 100, 95, 90 and 85% were recorded in Siyadebrna Wayu, Ensaro, Mojana Wedera and Moretna Jiru woredas, respectively. While the percent disease incidence of four selected Woredaswere Ensaro (30.4%), Moretna Jiru (32.25%), Siyadebrna Wayu (36.55%) and Mojana Wedera (27.8%). The fungal mycelia of the isolates were smooth, white in color and, abundant on PDA. The macro conidia were falcate shaped i.e. straight to slightly curved with 3 septation, While the micro conidia was oval shaped. Based on these the pathogen was identified as F. oxysporum f. sp. ciceris. The re-isolated fungus was confirmed to be Fusarium oxysporium f.sp. ciceris in order to full filling the requirement for Koch’s postulates by pathogenicity test. From the tested varieties Minijar, Yelbe and Kassech were relatively susceptible, the check variety Kutaye was relatively moderately resistant (tolerant) and Natoli, Mastewal and Areriti were relatively resistant. Based on the findings of the present study, the chickpea varieties, Natoli, Mastewal and Areriti are relatively resistance and can be recommended for the farmers in the study area since they perform better than the control.it is essential to do further research on molecular identification of the fungus associated with chickpea wilt.Item SURVEY OF ETHIOPIAN PEPPER MOTTLE VIRUSES IN THE CENTRAL RIFT VALLEY OF ETHIOPIA AND EVALUATION OF NETTING DURATION AS MANAGEMENT OPTION(Hawassa University College of Agriculture, 2018) KUMSA DIDA FAYEEthiopian pepper mottle virus is one of the major constraints of pepper production in the central rift valley region of Ethiopia. The present study was conducted to assess the prevalence of Ethiopian pepper mottle virus in the region and to determine optimum netting duration for efficient protection of pepper from vector infestation and subsequent viral infection. For this purpose, field survey and an experiment was carried out in the central rift valley of Ethiopia. The survey was conducted on 60 pepper fields in three districts i.e. Butajira, Meki and Ziway districts. Data were collected on the incidence of viral disease, plant height and number of pods per plant. In addition, field experiments were carried out at Hawassa and Meki to assess the efficacy of netting duration against aphid vectors and viral diseases. Data were collected on the number of aphid populations, virus incidence, and pepper growth parameters and yield. Visual inspection of the surveyed fields revealed that almost all the pepper fields (99.6%) had viral diseases. Viral disease incidence ranged from 52.8% in Ziway district to 68.6% in Butajira district. Furthermore, significant variations at (p<0.01) were observed between treatments of the field experiments in terms of aphid infestation, virus incidence and pepper yield. Covering of plots with net for up to 60 or more days after transplanting reduced aphids’ populationper plant by a greater margin (61.8%-76.9% in Hawassa; 52.4-67% in Meki) and virus incidence by 48%-60.8% in Hawassa and 38.6%-48.5% in Meki as compared to the control plots. Total and marketable yields were significantly higher in plots protected by net for up to 60 days or more after transplanting while unmarketable yields were low in those plots. Low virus incidence and aphids’ population in plots covered by net up to 60 days after transplanting and longer resulted in increased yields by 44 %-55 % in Hawassa and 38 %-49.5 % in Meki as compared to the control plots. Unmarketable yield was positively correlated (p<0.001) with aphids population and virus incidence while total and marketable yields were negatively correlated with aphids population and virus incidence. The current results suggest the need to apply control measures at early growth stages to effectively protect pepper plants from aphids and associated viruses.Item SURVEY OF TURCICUM LEAF BLIGHT (Exserohilum turcicum) ON MAIZE (Zea mays) AND EVALUATION OF MAIZE VARIETIES AND FUNGICIDE SPRAY FREQUENCIES FOR ITS MANAGEMENT(Hawassa University College of Agriculture, 2018) TAJUDIN ALIYI MOHAMMEDTurcicum leaf blight (Exserohilum turcicum), TLB, is a major disease affecting maize (Zea mays) in western Ethiopia. This study was designed to: assess the incidence and severity of TLB in major maize growing agro-ecologies of Western Oromia, evaluate the reaction of maize varieties under production to TLB, and determine optimum propiconazole (tilt 250 EC) frequency as management option to TLB. Survey was conducted on 172 farmers’ fields in 29 districts and five zones of major maize growing agro ecologies in western Oromia region of Ethiopia. Survey results revealed the prevalence of TLB across all the districts even though at different levels. Mean TLB incidence ranged from 16.3% in Abay chomen to 96.67% in Wayu Tuka and mean percent severity index varied between 3.1% in Abay chomen and 57.5% in Lalo Assoabi district. TLB was relatively more severe on maize varieties BH-540, Limu and Kolba on surveyed areas. In addition, the effects of maize varieties, fungicide frequencies and their interactions on TLB development were assessed in a field experiment during the 2016/17 main growing season at Ambo Plant Protection Research Centre (APPRC). The experiment involved three maize varieties and three fungicide (Tilt, propiconazole) frequencies arranged in a factorial setting in randomized complete block design with three replications. TLB was initiated following artificial inoculation. Data were recorded on disease incidence and severity and severity scores were used to calculate area under disease progress curve (AUDPC) and infection rate. Grain yield and yield components were measured after harvest. Finally correlation and economic analyses were carried out. Disease parameters varied markedly across treatments, especially variety-fungicide combinations had a highly significant variation (p<0.01) in disease parameters. The highest terminal percent severity index (PSI) (86.7%), AUDPC value (2614.4 %-day) and disease progress rate (0.09339 units-day -1 ) were recorded on unsprayed variety AMHQ-760. On the other hand, the same variety had significantly lower disease level and gave the highest grain yield (9.424 t ha -1 ) when it was treated three times with propiconazole. TLB resulted in grain yield losses of up to 62.4% on AMHQ-760. PSI, AUDPC, incidence and disease progress rate were negatively correlated with yield and yield components. The highest marginal benefit (ETB 63,089 ha -1 ), and marginal rate of return (ETB 14.53) were obtained from variety AMHQ-760 with thrice application of propiconazole. Based on current results, three propiconazole applications were found effective to manage TLB even on susceptible maize variety. However, additional experiments should be carried out to verify the current results.Item VARIABILITY FOR YIELD, YIELD COMPONENTS AND QUALITY VARIABILITY FOR YIELD, YIELD COMPONENTS AND QUALITY VARIABILITY FOR YIELD, YIELD COMPONENTS AND QUALITY OF POTATO (Solanum tuberosum Solanum tuberosum L.), CULTIVARS TESTED TESTED IN CENTRAL ETHIOPIA(Hawassa University College of Agriculture, 2019) ABDU YASSINThis experiment was conducted in three replications of the randomized complete block design at Debre Birhan during 2017 main growing season to assess the nature and magnitude of variability in twelve potato cultivars for tuber yield and nutritional quality. There were highly significant differences among twelve cultivars in all characters, except in days to maturity. The highest and lowest total tuber yield was obtained from Bubu (36.86 t ha-1) and Dinkey (16.28 ton ha-1), respectively. Genotypic and phenotypic coefficient of variation ranged from 0.79 to 88.9% and from 0.84 to 92.43%, respectively. Heritability and genetic advance as percent of mean (GAM) ranged from 65.35% to 97.53% and from 1.63% to 183.52%, respectively. High heritability values were coupled with high GAM for all characters except for plant height, total carotenoids, starch content and tuber dry matter for which heritability and GAM were moderate. These values were low for days to maturity and tuber specific gravity. Most of the traits can successfully be improved through hybridization and selection. Total tuber yield ha-1 was positively and significantly correlated with marketable tuber yield, average tuber weight, plant height and starch content but was negatively correlated with iron and crude protein content at both genotypic and phenotypic levels. Maximum positive direct effect on total tuber yield ha-1 was exhibited by average tuber weight at genotypic level and by marketable tuber yield ha-1 at phenotypic level. Cluster analysis showed that the cultivars were grouped into five clusters. Cluster I was high in average tuber weight and starch content. Cluster-III was high in total carotenoids, crude protein, iron and zinc but low in total tuber yield ha-1corroborating the negative correlation between tuber yield and nutritional quality except Zn content. Results of this study demonstrated that there is sufficient genetic variability among the potato cultivars. However, it is difficult to make conclusion with one season and one location experiment. Therefore, it is recommended to evaluate more cultivars over locations and seasons to reach on more valid conclusion.