Field survey was conducted in south eastern Ethiopia to determine the disease intensity of chocolate spot and rust and to investigatethe association of disease intensity (incidence and severity) with environmental factors and crop cultural practices. A total of 280faba bean fields were surveyed in eight districts, and type of cropping system, weed management practices, crop growth stage,previous crop in the field, and sowing date were recorded. The associations of disease intensity with independent variables wereevaluated using logistic regression model. Mean disease incidence of chocolate spot varied from 70.9 to 93.2% in most fields whilepercentage severity index (PSI) ranged from 10.5 to 47.1%. In a reduced multiple variable model, chocolate PSI ≤ 30% showed highprobability of association with mixed cropping system, good weed management practices, late planting, and when faba bean wasrotated with vegetables and cereals. The mean disease incidence of faba bean rust was varied from 23.6 to 78.2%, while the meanPSI of rust was varied from 4.8 to 37.9%. In Gasera, Dinsho, and Agarfa districts, poor weedmanagement practices, fields planted inthe month of July, and when previous crop was legume had a high probability of association to (>20) rust PSI in a multiple variablereduced model. In contrast, soil types, fertilizer applied, and fungicides sprayed were not associated with disease intensity. Thepresent study has identified cropping system, planting date, previous crop, district, and weed management practices as importantvariables that influence faba bean chocolate spot and rust epidemics in diversified fields. Therefore, proper weeding managementpractices, late planting, crop rotation habit, and other related farm practices should be carried out to reduce chocolate spot and rustimpact until resistant faba bean genotypes are developed and distributed to the area.
1. Introduction
Faba bean (Vicia faba L.) is an important pulse crop producedall over the world for humans as a source of protein andcarbohydrate and for animal feeds [1]. It is also an excellentcrop for fixing atmospheric nitrogen and as green manure[2, 3]. In addition, faba bean is used as a source of cashcrop to farmers and foreign currency in Ethiopia [4]. Fababean is the sixth most important grain legume with 4.3million tons of annual production worldwide. Next to China,Ethiopia is the second largest producer of faba bean [5, 6] withannual production of 0.88 million tones and nearly covers0.43 million hectares of lands counting about 31.2% of totalpulse production of the country [7].
In spite of its various importance, the productivity offaba bean in Ethiopia remains far below the crop’s potential
(3.8t/ha), which has been constrained by several biotic andabiotic factors [8–11]. Climate change (variability), edaphicfactor, water stress, and colds are among major abiotic con-straints of faba beanproduction.Moreover, climate variabilitydue to increased temperature and erratic precipitation overtime has increased susceptibility of faba bean which alsofavoured disease development [12]. As a result of climatechange different fungal pathogen evolved, seriously affectingthe production of faba bean [13, 14]. Thus, climate changeand associated factors of disease scenarios demand changesin crop and disease management strategies.
More than seventeen pathogens have been reported so faron faba bean from different parts of Ethiopia [11]. Of themthe most important yield limiting diseases are chocolate spot(Botrytis fabae), rust (Uromyces viciae-fabae), and black rot(Fusarium solani). Particularly, chocolate spot and faba bean
HindawiAdvances in AgricultureVolume 2018, Article ID 6042495, 13 pageshttps://doi.org/10.1155/2018/6042495
rust are themost serious and economically damaging diseasesthat affect the foliage, limit the photosynthetic activity,and reduce the productivity of faba bean, globally [15–17].Chocolate spot is a major limiting factor in the main fababean growing regions of Ethiopia resulting with yield lossesranging from 34.1 to 61.2% [14, 18]. Faba bean rust is alsoa severe disease which causes about 70% of faba bean yieldlosses across the world in general [10] and in the Middle East,North Africa, Ethiopia, and parts of Australia in particular[16, 19, 20]. In Ethiopian context there is rust devastatingdisease following chocolate spot, which causes 2 to 15% and14-21% seed yield loss, respectively, in lower and intermediatealtitudes [12]. Together, rust and chocolate spot may causetotal crop failure under severe epidemic conditions, resultingwith more than 50% yield losses [16, 21].
Sahile et al. [22] reported that different productionpractices such as planting date, weed management, croppingsystem, and previous crop can influence disease occurrence,epidemic development, and the damage caused to the crops.The disease severity can also be influenced by certain farmingsystems, field location, and/or season. Management optionsfor chocolate spot and rust disease in Ethiopia include useof resistant cultivars, chemical control (Mancozeb), and lateplanting, but these options were neither widely disseminatednor adopted by end users (farmers) [8].
Information concerning the distribution and importanceof chocolate spot and rust has not been systematicallyanalyzed in major faba bean growing areas of the country;especially in the south eastern parts the information is totallylacking. Accordingly, as the diseases become a recurrentproblem in the major faba bean production areas of thecountry, it is imperative to develop an effective integratedchocolate spot and rust management package, which issustainable in agricultural yield development, knowledgeof the relationships of the disease with different variables[23]. Thus, the information obtained from survey work isnecessary for planning management strategies; the presentstudy aimed at investigating (i) the incidence and severityof chocolate spot and rust diseases and (ii) association ofchocolate spot and rust with farmers cultural practices inthe major faba bean growing areas of Bale Highlands, southeastern Ethiopia.
2. Materials and Methods
2.1. Survey Areas. The survey was conducted in eight dis-tricts of Bale highlands (i.e., Agarfa, Dinsho, Gasera, Goba,Gololcha, Goro, Ginir, and Sinana) during the main croppingseason of 2017. The selection of the districts was based onfaba bean production and productivity across south easternEthiopia as well as their accessibility to road. Mainly thedistricts were differed in altitude, weather, and soil charac-teristics (Table 1). The rainfall data of the surveyed districtswere obtained from meteorological stations. A total of 280faba bean fields were inspected to assess the magnitude ofchocolate spot and rust disease. The time of survey waschosen so as to coincide with the time of flowering, podding,and late podding stages of faba bean, when the diseases
reached its maximum [10, 22]. The districts surveyed wereshown in Figure 1.
2.2. Sampling and Disease Assessments. Fields were sampledrandomly at the interval of 5–10 km along roads. Dependingon the topography and the relative importance of faba beancultivation within each district the distances between fieldswere determined. In each sampled field, four quadrants(2m×2m) 10m away from each other were sampled bymakingdiagonal moves with four throws in order to represent fourreplications per field. Following each throw, the numberof healthy and infected (chocolate spot and rust) leaves of12 plants within the area were recorded. A subsample oftwelve leaves per plant and four leaves per canopy layers(upper, middle, and lower) were selected from the mainstem, yielding a total of 144 leaves per field. Mean of canopylayers was determined per plant and then averaged per fieldfor data analysis. Chocolate spot and rust incidence wererated as mean percentage of diseased plant leaves withinthe quadrant. Severity was rated on leaves from the same 12representative plants in each quadrat, using a 1–9 scale [24], inwhich 1 indicates no visible symptom and 9 represents diseasecovering more than 80% of the foliar tissue. Disease severityscores were converted into percentage severity index (PSI) forthe analysis [25, 26].
PSI
=Sum of numerical ratings × 100
No. of plants scored ×Maximum score on scale
(1)
During the survey, cultural practices like soil type (vertisol,loam, and clay), cropping system (mixed or sole), weedmanagement practices, type of fungicide applied, previouscrop, planting date, and crop growth stages of every sampledfield were recorded.
2.3. Data Analyses. Disease incidence and PSI were classifiedinto distinct groups of binomial qualitative data. Thus, ≤75and >75% were chosen for chocolate spot incidence yieldinga binary variable and class boundaries of ≤30 and >30% werechosen for chocolate spot PSI data (Table 2). Class boundariesof≤50% and >50% for rust incidence and ≤20 and>20%werechosen for rust PSI data.
Logistic regression analysis was used to determine theassociation of faba bean rust and chocolate spot incidenceand PSI with independent variables (climate change resilientcultural practices) using SAS Procedure GENMOD [11, 22,27–29]. Logit link function was used to determine theeffects of climate change resilient cultural practices to theresponse variable. The importance of independent variableswas evaluated three times for their effect on the responsevariable. At first, all the independent variables were testedwith faba bean rust and chocolate spot incidence and PSIin a single variable model. Second, the association of anindependent variable with disease incidence or PSI was testedwhen entered last into the model with all other independentvariables. Third, those independent variables which showed
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Figure 1: Map of Ethiopia and the Bale highlands showing the surveyed districts.
high significant association to the disease incidence and PSIwere added in to a reduced multiple variable model.
Furthermore, parameter estimates and standard errorwere analyzed in both single and multiple models. Odd ratiowas obtained by exponentiating the parameter estimates forcomparing variable classes based on reference point. Analysis
of deviance and likelihood ratio statistics were used tocompare single and multiple variable models. The differencebetween likelihood ratio tests was used to examine theimportance of variables and tested against a Chi-square value.Data analysis and interpretation were done as described byYuen [30].
4 Advances in Agriculture
Table 1: Characteristic features of surveyed faba bean fields in eight districts of Bale highlands, south eastern Ethiopia.
District Altitude (m. a. s. l) Annual total rainfall (mm) Temperature (∘C) Soil typeAgarfa 2328-2505 907 10-24 VertisolDinsho 2528-2599 1170 5-20 ClayGasera 2341-2428 878 8-24 VertisolGinir 1889-2289 983 14-27 LoamGoba 2445-2600 935 9-23 VertisolGololcha 1993-2102 994 12-27 VertisolGoro 1805-2237 920 9-32 LoamSinana 2374-2456 878 6-24 Vertisol
3. Results
3.1. Characteristics Features of the Surveyed Fields. The alti-tude of surveyed fields ranged from 1805 in Goro districtto 2600 m.a.s.l. in Goba district (Table 1). Aggregation ofindependent variables were used to analyze the survey of fababean chocolate spot and rust into distinct variable classeswithin a number of corresponding fields for each class aspresented in Table 2. Out of the total surveyed 280 faba beanfields, 81.43% of them were sole cropped, while 18.57% hadbeen intercropped with wheat, barley, maize, and oat. Fieldshaving poor weedmanagement showed the highest incidenceand severity of chocolate spot and rust compared to otherrespective variable classes. The weeds commonly observedduring the survey were species of Trifolium, Rumex, grasses,and Solanum nigrum. Faba bean fields were at three growthstages during the survey, with 5.4% at flowering, 37.8 % atpodding, and 56.8% at the late podding stages. About 37% offaba bean fields were sown in the month of July, while 19.6%and 43.2%were sown in themonths of August and September,respectively (Table 2).
3.2. Chocolate Spot Disease Intensity and Its Associationwith Climate Change Resilient Cultural Practices. Chocolatespot was prevalent in across the faba bean fields surveyed.Different levels of chocolate spot incidence and PSI wererecorded among the districts. Highest mean disease inci-dence of chocolate spot was recorded in Gasera (93.2%),Goba (92.1%), Agarfa (90.7%), Gololcha (89.3%), and Dinsho(87.6%), whereas the lowest was observed in Goro (70.9%)district (Table 3). Also, the highest mean PSI of chocolate spotwas recorded in the districts of Agarfa, Dinsho, Goba, andGasera (32.9-47.1%), as the lowest was in Ginir (23.3%) andGoro (10.5%) districts.
The highest chocolate spot mean disease incidence of90.4% and PSI of 37.5% were recorded from fields plantedin the month of July, while the lowest incidence (85.2%)and PSI (23.4%) were recorded in September (Table 3). Onthe other hand, the highest mean incidence (91.5%) andPSI (37.9%) were recorded from fields highly infested withweeds when compared with field managed in a good way. Insome fields, faba bean was planted along with other cropssuch maize, barley, wheat, oats, potato, garlic, and onion.Consequently, a relatively lowest (87.5%) mean incidence ofchocolate spot was recorded from suchmixed fields, contrary
to faba bean planted as sole cropping system with the highestmean incidence of 90.5%.The highest (89%) mean incidenceof chocolate spot was recorded from fields planted withlegume crop in the preceding year. The highest (36.2%)meanPSIwas observed at late podding stage and the lowest (30.9%)at flowering stage.
The association of all independent variables with choco-late spot incidence and PSI is presented in Table 4. Theindependent variables such as district, planting date, previouscrop, cropping system, and weed management practices werehighly associatedwith chocolate spot incidence and PSIwhenentered into the logistic regression model as a single variable.However, when all variables entered last into the regressionmodel, soil type, altitude, and growth stage showed significantassociation with chocolate spot incidence in addition toother variables. Among the independent variables, district,previous crop, altitude, growth stage, weed management,planting date, and cropping system were the most signifi-cantly important variables that are associated with chocolatespot incidence as a result of the reduced multiple variablemodel indicated.
The analysis of deviance for the variables added one byone to the reduced model showed the importance of eachvariable and variable class. The parameter estimates resultingfrom the reduced regression model and their standard errorare given in Table 5.
High chocolate spot incidence has a high probabilityof association to Gasera district, when previous crop waslegume, late podding stage, poor weed management practice,July sowing, and sole cropping system. In Gasera district,therewas about twenty-six times greater probability of choco-late spot incidence observed that exceeds 75%. Again, amongthe independent variables, such as district, sowing date,previous crop, cropping system, and weed management werefound as the most important variables in their associationwith chocolate spot PSI when entered first and last intothe model with other variables (Table 4). A chocolate spotPSI of ≤30% showed high probability of association withcereals and vegetable as previous crop, faba bean planted late(September), mixed cropping system, good weed manage-ment practice, and low altitude (Table 6).
3.3. Rust Disease Intensity and Its Association with ClimateChange Resilient Cultural Practices. The highest mean inci-dence of faba bean rust was recorded in Gasera (78.2%),
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Table 2: Independent variable by disease contingency table for logistic regression analysis of chocolate spot and rust during 2017 maincropping season in eight districts (n=280) of Bale highlands, south eastern Ethiopia.
Independentvariable Variable class Total number
of fields
Number of fields in different chocolate spot and rust categoriesChocolate spot Rust
aPercentage severity index.bFaba bean intercropped with cereals (wheat, mai, and oats) and vegetables (potato, garlic, and onion).
Goba (56.6%), and Ginir (56.5%), whereas the lowest wasrecorded in the districts of Goro (23.6%) (Table 3). Thehighest mean rust severity was recorded in Gasera (37.9%)and Dinsho (24.5%). The highest mean incidence (53.5%)and severity (26.4%) of rust were observed on fields sownin July while the minimum mean incidence (39.4%) andseverity (11.2%) were in September. The highest (56.8%)mean incidence of faba bean rust was recorded from fieldsfound at high altitude (>2500m a.s.l.) and the lowest (45.3%)
was recorded from fields found at low altitude (<2200).The highest mean incidence of faba bean rust was recordedfrom fields highly infested with weed (63.2%) than fieldswith less weed population. The highest mean incidence ofrust (50.2%) was recorded from fields planted with legumecrop from the previous year. Rust severity was found toincrease with the advancement in growth stage, in whichmaximum mean rust severity was recorded at late pod-ding stage (36.7%) and on fields sown faba bean alone
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Table 3: Mean incidence and percentage severity index (PSI) of faba bean chocolate spot and rust for different independent variables during2017 main cropping season in Bale highlands, south eastern Ethiopia.
(25.3%) compared to their respective other variable classes(Table 3).
The independent variables varied in their associationwithrust incidence and PSI (Table 7). Of them, district, plantingdate, previous crop, growth stage, and weed managementshowed significant associations (P < 0.01) with rust inci-dence. These independent variables were tested in a reducedmultiple-variable model. The parameter estimates resultedfrom the reduced regression model and their standard errorswere presented in Table 8. A rust incidence of ≤50% showed ahigh probability of association with good weed management,late sowing (September), and rotation of faba bean withcereals and vegetables. Conversely, a high rust incidencewas associated with poor weed management practices, early
sowing, flowering stage, and continuous monocropping offaba bean (Table 8). However, the fertilizer, fungicides, soiltypes, and altitude were not significantly associated with therust incidence.
Five variables, district, planting date, previous crop,altitude, growth stage, and weed management practices wereassociated with rust PSI when entered as single variable intothe model (Table 7). The significance of district, previouscrop, growth stage, weed management, and planting datewere tested by adding these variables into a multiple reducedmodel (Table 9). Analysis of deviance for the variables,parameter estimates, and their standard errors is givenin Table 9. Gasera, Dinsho, Agarfa, and Goba districts,fields sown in the month of July along with poor weed
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Table 4: Independent variables used in logistic regression modeling of chocolate spot incidence and percentage severity index (PSI) andlikelihood ratio test (LRT) for ten variables entered first and last into a model.
Table 5: Analysis of deviance, natural logarithms of odds ratio, and standard error of added variables in a reducedmodel analyzing chocolatespot incidence.
Added variablea Residual devianceb DF LRT Variable class Estimatec SEd Odds RatioeDR Pr > 𝜒2
DF, degrees of freedom; LRT, likelihood ratio test; DR, deviance reduction; Pr, probability of 𝜒2 value exceeding the deviance reduction. ∗, reference group.aVariables are added into the model in order of presentation in table.bUnexplained variations after fitting the model.cEstimates are from the model with all independent variables added.dStandard error of the estimate. eExponentiating the estimates.
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Table 6: Analysis of deviance, natural logarithms of odds ratio, and standard error of added variables in a reducedmodel analyzing chocolatespot percentage severity index (PSI).
Added variablea Residual devianceb DF LRT Variable class Estimatec SEd Odds RatioeDR Pr > 𝜒2
DF, degrees of freedom; LRT, likelihood ratio test; DR, deviance reduction; Pr, probability of 𝜒2 value exceeding the deviance reduction; ∗, reference group.aVariables are added into the model in order of presentation in table. bUnexplained variations after fitting the model. cEstimates are from the model with allindependent variables added. dStandard error of the estimate. eExponentiating the estimates.
Table 7: Independent variables used in logistic regression modeling of faba bean rust incidence and percentage severity index (PSI) andlikelihood ratio test (LRT) for ten variables entered first and last into a model.
Table 8: Analysis of deviance, natural logarithms of odds ratio, and standard error of added variables in a reducedmodel analyzing faba beanrust incidence.
Added variablea Residual devianceb DF LRT Variable class Estimatec SEd Odds RatioeDR Pr > 𝜒2
DF, degrees of freedom; LRT, likelihood ratio test; DR, deviance reduction; Pr, probability of 𝜒2 value exceeding the deviance reduction;∗, reference group.aVariables are added into the model in order of presentation in table. bUnexplained variations after fitting the model. cEstimates are from the model with allindependent variables added. dStandard error of the estimate. eExponentiating the estimates.
management, had a high probability of association to high(>20%) rust PSI. There were about 150 times greater proba-bilities that rust PSI would exceed (>20%) in Gasera districtthan Sinana district and 19 times higher in the fields plantedduring the month of July compared to September.
4. Discussion
Faba bean chocolate spot and rust were found to be widelyspread across all the studied districts and the incidence andseveritywere varied among altitude ranges, cropping systems,and other cultural practices. Furthermore, the higher totalannual rainfall (878mm-1170mm) aswell as the temperatures(5-32∘C) of the area (Table 1 and Figure 2) has createdfavorable environmental condition for both diseases. Whentemperatures aremild (15-22∘C) and relative humidity is high,chocolate spot can kill the plant [31], while rust is favoredby warm temperatures and cloudy weather conditions [20].Therefore, chocolate spot and rust seriously damage faba beanand their spread which were strongly influenced by climaticconditions [32].
Evident from the finding of this study is that intercrop-ping faba bean with cereals (barley, wheat, maize, and oats)and vegetables (potato, garlic, and onion) appears to be aneffective strategy to control chocolate spot and rust. These
also concur with the results of previous researchers whofound that intercropping reduced disease severity relative tomonocrops in 79% of studies involving fungal pathogens,72% of studies of virus diseases, 100% of bacterial stud-ies, and 37% of nematode studies [33]. The advantages ofdiversification may accrue to smallholders in the developingtropics, where intercropping is still widely practiced [34].Dueto the high tillering capacity of cereal crops as comparedto legume, intercropping cereals and vegetables with fababean resulted with modifying the microclimate in favourof disease epidemic and reducing effective spore populationby trapping. Besides, cereals could act as a physical barrierby intercepting spores carried by wind from neighbouringinfected faba bean plants thereby reducing the amount ofeffective inoculum available to infect new tissue [35]. Similareffects have also been reported in pea-cereal intercropsintercepting Mycosphaerella pinodes spores [36]. Sahile et al.[9] have found chocolate spot reduction in faba bean-maizeand faba bean-barley intercrops and not in a faba bean-peaintercrop. However, Dillon Weston [37] stated that faba beanintercropped with pea, barley, and oats was almost chocolatespot-free. Schoeny et al. [36] considered that reduction inhost density was responsible to a large extent for reductionsof M. pinodes dispersal in pea-barley intercrops, with asignificant contribution of non-host plant by providing aphysical barrier.
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Table 9: Analysis of deviance, natural logarithms of odds ratio, and standard error of added variables in a reducedmodel analyzing faba beanrust percentage severity index (PSI).
Added variablea Residual devianceb DF LRT Variable class Estimatec SEd Odds RatioeDR Pr > 𝜒2
Planting date 107.8 2 17.7 0.0001July 2.93 0.99 18.72
August 2.12 0.87 8.30September 0∗ 1
DF, degrees of freedom; LRT, likelihood ratio test; DR, deviance reduction; Pr, probability of 𝜒2 value exceeding the deviance reduction; ∗, reference group.aVariables are added into the model in order of presentation in table. bUnexplained variations after fitting the model. cEstimates are from the model with allindependent variables added. dStandard error of the estimate. eExponentiating the estimates.
Throughout the surveyed areas it was observed that plantswere infected by chocolate spot and rust in poorly weededfields. Thus, high weed population not only severely reducesthe yield of the crop but also favours the developmentof disease epidemics (Agegnehu and Fessehaie 2006). Thismight be in fields with dense weed populations; there wascompetition for space, moisture, and soil nutrients as a resultof which the faba bean plants were less vigorous and proneto the disease. Similarly, white rot of garlic [38] and root rotof faba bean [39] have been reported that high weed densityin non-weeded fields increased disease severity. Besides, thepresence of a high weed population in a field increases thehumidity within the crop canopy (microclimate) which ismore favorable for B. fabae infection and the development ofchocolate spot disease epidemics [22].
Maximum chocolate spot and rust incidence wereobserved from fields sown legume crop in the previous yearparticularly in Gasera and Agarfa districts. The farmers ofsurveyed area produce faba bean crop continuously and thepreceding crop residual appears to be a source of inoculum.This continuous growing of faba bean leads to accumulationof plant haulms in the field; as a result, there was an increasein the inoculum level, as well as rapid amplification of thedisease. In cooler production regions, the uredospores areimportant means of survival between cropping seasons forfaba bean rust (Shifa et al. 2011). Secondary spread is by
means of uredospores, which can readily germinate on plantsurfaces under humid conditions and dispersed by wind[20]. In support of this, Zewude et al. (2007) reported thatcontinued growing of garlic leads to accumulation of thewhite rot sclerotia in the soil that increases the occurrenceof white rot. The importance of crop rotation is also affirmedby Belete et al. [39] who stated that faba bean cultivation isdeclining steadily due to root rot, as farmers substitute thiscrop with other legumes, mainly grass pea (Lathyrus sativus).
Planting date was also found as another factor influencingthe incidence and severity of faba bean chocolate spot andrust in the study area. Accordingly, high mean disease inci-dence of chocolate spot was recorded from fields sown in July(early season). This particular period of time is characterizedby high rainfall and humidity that favour leaf wetness whichcaused infection on plant leaf, due to the extended infectionperiod of the pathogen in the air. Early infection producestypically dark-brown spots that do not pose a serious threat tothe crop. However, when environmental conditions becomemore favourable for the development of the disease (that is,mild temperatures and high humidity) aggressive lesions mayappear. In this case, a rapidly expanding necrosis takes placewhich may eventually lead to defoliation and death of thewhole plant [31]. Hence, in agreement with the literaturesmore severe epidemic occurred at Gasera, Agarfa, and Din-sho districts by the milder temperature favouring epidemic
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development. Similar results were also found by Belete et al.[39] that high root rot incidence occurred in the faba beanplants sown in early season. Likewise, Shifa et al. [1] showedhigh faba bean rust severity in fields sown between June andJuly, a time considered as an early sowing period in Hararghehighlands. Outside the Ethiopia context, Hawthorne et al.[40] have indicated that early sowing faba bean may result ina bulky crop, which creates an environment most conduciveto rust disease in Australia. Therefore later sowing reducedthe disease risk in faba bean fields.
5. Conclusions
This study indicated that chocolate spot and rust diseaseswere widely distributed and major challenging diseases infaba bean growing districts of Bale highlands.The survey dataanalyzed using logistic regression model identified climatechange resilient cultural practices that are associatedwith rustand chocolate spot epidemics either singly or in combina-tion. The present study has identified that intercropping offaba beans with cereals and vegetables reduced the impact
12 Advances in Agriculture
of chocolate spot and rust development on faba bean. Inaddition, the study has identified the importance of sowingdates, previous crop, and weed management practices asclimate change resilient cultural management components inchocolate spot and rust management strategies. Therefore,proper weeding practices, sowing at appropriate time, croprotation with non-legume, mixed cropping system, and otherrelated cultural practices should be carried out to reducerust and chocolate spot impact on faba bean productionand productivity until ecofriendly integrated managementstrategies are developed for the faba bean growing districtsof Bale highlands.
Data Availability
If raw data is required, it is possible to get it from correspond-ing author upon request.
Conflicts of Interest
The authors declare that there are no conflicts of interestregarding the publication of this paper.
Acknowledgments
We acknowledge Madda Walabu University for financialsupport.
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