Review of Plant Studies 2019 Vol. 6, No. 1, pp. 11-20 ISSN(e): 2410-2970 ISSN(p): 2412-365X DOI: 10.18488/journal.69.2019.61.11.20 © 2019 Conscientia Beam. All Rights Reserved. EVALUATION OF FABA BEAN (Vicia faba L.) VARIETIES AGAINST FABA BEAN GALL DISEASE IN NORTH SHEWA ZONE, ETHIOPIA Wulita Wondwosen1+ Mashilla Dejene2 Negussie Tadesse3 Seid Ahmed4 Debre Birhan Agricultural Research Center, Debre birhan, Ethiopia. 1 School of Plant Sciences, Haramaya University, Dire Dawa, Ethiopia. 2 International Center for Agricultural Research in the Dray Areas, Addis Ababa, Ethiopia. 3 (+ Corresponding author) Biodiversity and Integrated Gene Management Program, ICARDA, Rabat Institutes, Morocco. 4 ABSTRACT Article History Received: 6 September 2019 Revised: 10 October 2019 Accepted: 13 November 2019 Published: 16 December 2019 Keywords Faba bean Faba bean gall Percent severity index AUDPC Varieties Yield. Faba bean gall disease is a newly emerging and devastating disease of faba bean that threaten its production and productivity in Ethiopia. Thus, this study was conducted with the objective to evaluate the reactions of faba bean varieties against faba bean gall disease. A field experiment was conducted at Basona Werana and Ankober Districts, in 2014. Sixteen faba bean varieties along with local check were tested in RCBD design with three replications. Faba bean varieties varied significantly (p<0.05) for both disease and yield parameters. The lowest disease severity, AUDPC and infection rates were recorded from variety Gachena (Lay Gorebela) and Gora and Gachena (Mush). Moreover, the highest (2737 and 3374%-days) AUDPC values were recorded from the variety local and Selale at Mush and Lay Gorebela. The highest yield was obtained from varieties Gora, Gebelcho, Degaga, Gachena and Walki (Mush) and from varieties Gora and Gachena (Lay Gorebela). Also, yield of faba bean correlated negatively and significantly with AUDPC and final severity at both locations, whereas, AUDPC and severity associated positively and significantly from each other. From this study it can be concluded that relatively resistant and high yielder varieties can be used in combination with other control measures. Therefore, in the future, researches on integration of resistance and high yielder varieties with other management options should be conducted. Contribution/Originality: This study is one of the very few studies in Ethiopia which have investigated the response of Faba bean varieties for the newely emerged gall disease. The study assessed seventeen varieties by scientifically comparing them with very important agronomic and disease resistance related attribute and come up with valid conclusion. 1. INTRODUCTION Faba bean (Vicia faba L.) is grown in many countries as a rain-fed and irrigated crop for human food and animal feed and plays important roles in the national economy and agricultural production in various ways. Faba bean is a leading protein crop in and covered over half a million ha and production of close to one million tonnes of grain and 1.2 million tonnes of straw [1]. Moreover, despite the availability of high yielding varieties, the average national yield of faba bean under small-holder farmers is not more than 1.8 t ha-1 [1]. Various biotic, abiotic and 11 © 2019 Conscientia Beam. All Rights Reserved. Review of Plant Studies, 2019, 6(1): 11-20 anthropogenic factors have attributed to this low productivity of the crop. According to Samuel, et al. [2] diseases are the most important biotic factors limiting the production of faba bean in Ethiopia. Many diseases are affecting faba bean production and productivity, but only a few of them have economic significance. Recently, faba bean gall has become a serious threat to faba bean production and productivity in some parts of the country causing a yield loss as high as 100% [3]. In Ethiopia, the disease was first reported as a faba bean “gall” in North Shoa (Degem, Bash Area of Menz Mama and Mojana Wedera district) in 2011 [3, 4]. A survey conducted in major faba bean-growing districts of North Shoa indicated that the disease was new and problematic in all faba bean-growing districts [5]. Moreover, according to the survey conducted in 2013, the disease has spread to the highland faba bean-growing areas of Amhara, Tigray, and Oromia regions [6]. This shows that the spread of the disease has been very fast and expanding from year to year in all faba bean growing areas of the country. Now, a little effort has been made for the control of this disease including fungicide sprays and screening of germplasms. Furthermore, it is hypothesized that different faba bean varieties and fungicides had different effect on this disease. So far, little has been known about this disease and there are no varietal recommendations against faba bean gall in North shewa zone. So, if appropriate strategy is not devised to curb the progress of the disease and to manage it timely, obviously the disease would continue to devastate vast areas of faba bean producing regions shortly, constraining the national production of this economic crop. Thus, this study was conducted with the objective to evaluate the reaction of selected faba bean varieties against faba bean gall disease and its effect on yield and yield related components. 2. MATERIALS AND METHODS 2.1. Experimental Sites The experiment was conducted on the farmers‟ fields that were considered as “hot-spot” for faba bean gall under rain- fed conditions at Basona Werana and Ankober Districts, North Shoa Zone Figure 1. The specific experimental sites were Mush Kebele or Farmers Association (in Basona Werana District) and Lay Gorebela Kebele or Farmers Association (in Ankober District), which are hot-spot areas for the disease and that are located 20 and 42 km north and north-east of Debre Birhan town, respectively. Mush Kebele is found at an altitude of 2975 m.a.s.l. and receives average annual rain fall of 897.8 mm with mean minimum and maximum temperatures of 6.1 and 19.67 oC, respectively. Ankober Kebele is found at an altitude of 3152 m a.s.l. The area receives mean annual rainfall of 1793 mm with average minimum and maximum temperatures of 13 and 27 oC, respectively. 2.2. Experimental Materials and Design A total of 17 faba bean genotypes (16 improved faba bean varieties Table 1 along with one local variety of each location (Ankober and Mush) were planted in 2014 main cropping season. The experiment was laid out in a randomized complete block design (RCBD) with three replications and with a plot size of 1.6 m x 2 m. Four rows per a plot each accommodating 20 plants were used and an inter-row and intra-row spacing of 40 cm and 10 cm, respectively, were used. Gangways of 0.5 and 1 m were used between plots and replications, respectively. Full dose of phosphorous (46 kg ha-1) and nitrogen (18 kg ha-1) fertilizer was applied once at planting (i.e. on June 24 and 25 at Mush and Ankober, respectively) in the form of di-ammonium phosphate (DAP) just below the seed with light covering of soil to avoid direct contact with the seed. All other non-experimental variables and agronomic operations were applied uniformly to the entire experimental areas and throughout the experimental time. 12 © 2019 Conscientia Beam. All Rights Reserved. Review of Plant Studies, 2019, 6(1): 11-20 Figure-1. Map of the experimental sites. 2.3. Data Collected From Field Experiments a. Disease Parameters Days to disease onset: Measured as the date on which the disease was first noticed. Disease severity: Disease severity was recorded on 20 randomly selected plants in the two central rows of each plot starting from the onset of the disease and repeated after every 10 day intervals. A 0-9 scale was used where 0 = no disease symptom observed, 1 = < 2% plant parts infected, 2 = 2 - 5% plant parts infected, 3 = 6 - 10% plant parts infected, 4 = 11 - 25% plant parts infected, 5 = 26 - 50% plant parts infected, 6 = 51 – 75% plant parts infected, 7 = 76 - 90% plant parts infected, 8 = 91 - 99% plant parts infected, 9 = 100% plant parts infected [7]. Disease severity scores were converted into a percentage severity index (PSI) for analysis [8]. In the formula, Snr is the sum of numerical ratings, Npr is number of plant rated, Msc is the maximum score of the scale. Means of the severity from each plot were used in data analysis. Area under disease progress curve (AUDPC): AUDPC was calculated for each plot using the formula of Shaner and Finney [9] and was expressed in %-days. 13 © 2019 Conscientia Beam. All Rights Reserved. Review of Plant Studies, 2019, 6(1): 11-20 Where Xi is the cumulative disease severity at the ith observation, ti is the time (days after sowing) at the i th observation and n is the total number of observations. Disease progress rate: Logistic, ln[Y/(1-Y)] [10] and Gompertz, -ln[-ln(Y)] [11] models were compared for the estimation of disease development from each treatment. The goodness of fit of the models was tested using the coefficient of determination (R2) and residuals (SE) [12]. b. Crop Parameters Plant height (cm), number of pods per plant, number of seeds per pod,. 100 seed weight (gm) and total grain yield (t ha-1) were recorded. 2.4. Data Analysis The collected data were subjected to analysis of variance (ANOVA) to determine the treatment effects. All the disease reactions for each treatment were evaluated by averaging the data from the individual plants. The data on incidence and severity were subjected to square root transformation before analysis. Means that are significantly different were compared using Duncan Multiple Range Test (DMRT) at 5% probability of significance. Correlations of yield with disease and yield components were examined via correlation analysis using SAS software following the standard procedure [13]. Table-1. Faba bean varieties evaluated for their reaction against the newly emerged disease in the 2014 main cropping season. No. 1 2 3 4 5 Faba bean varieties Adet-Hanna Angacha-1 CS-20-DK Dagm Degaga Year of release 2005 2009 1977 2002 2002 Altitude (m.a.s.l.) 2224-2630 2000-2800 2300-3000 2600-3000 1800-3000 Yield (Qt ha-1) Research field 15-39.5 30-40 20-40 35 32 6 7 8 9 10 Dosha Gachena Gebelcho Gora Hachalu 2009 2008 2006 2013 2010 2050-2800 2000-3000 1900-2800 1900-2800 28-62 17-30 25-44 44.1 32-45 11 12 13 14 Lalo Moti Obse Selale 2002 2006 2007 2002 2600-3000 1900-2800 1900-2800 2000-2800 36 28-51 25-61 23.3 15 16 Tumsa Walki 2010 2008 2050-2800 1900-2800 25-69 24-52 17 Local variety Ns Ns Description of the varieties High yield, wide adaptation High yield, wide adaptation High yield, wide adaptation High yield, wide adaptation High yield, diseases resistance, wide adaptation High yield, wide adaptation, export type High yield, wide adaptation High yield, wide adaptation, export type High yield, wide adaptation, export type High yield, water-logging and black root rot resistance, wide adaptation, export type High yield, wide adaptation High yield, wide adaptation, export type High yield, disease resistance Water-logging and black root rot resistance High yield, wide adaptation, export type High yield, water-logging and black root rot resistance, wide adaptation, export type Ns Source: MoARD, Variety Registration Book, Issue numbers 5-13N; Ns: Not specified. 3. RESULTS AND DISCUSSION 3.1. Disease Onset The symptom of faba bean gall disease was evident at 39 and 47 DAS at Mush and Ankober, respectively. The disease appeared on all varieties during the first assessment at both locations. The incidence of the disease was 100% after second (Mush) and third (Ankober) assessments. 14 © 2019 Conscientia Beam. All Rights Reserved. Review of Plant Studies, 2019, 6(1): 11-20 3.2. Percentage Severity Index (PSI) The analysis of variance (ANOVA) revealed that there was significant difference (p ≤ 0.05) among varieties in percent severity index at both locations Table 2. At Lay Gorebela, when the disease developed naturally, the local variety instigated to show significantly higher (2.09%) level of PSI, whereas the variety Gachena showed lower (1.34%) level of PSI at 47 DAS. This finding corroborate the result of Getnet and Yehizbalem [14] who reported that different level of severity recorded on different faba bean varieties tested at different locations. Likewise, the highest (72.19%) level of PSI was recorded from the variety Selale, whereas, the lowest PSI was recorded from the variety Gachena (56.30%) at the final assessment (127 DAS). Accordingly, at this assessment date, the variety the Gachena reduced PSI by 22.01% as compared to Selale variety indicating the presence of different levels of resistance among faba bean varieties against faba bean gall disease. This current result agrees with Bond and Pope [15] who stated that on natural epidemics: the rate of disease development is affected by resistant levels of the crop. Also, at Mush, initial PSI ranged from 1.95% (local variety) to 3.1% (variety Gora). Likewise, the consequent maximum i.e.78.09 and 76.22% severities were recorded from the variety Selale and local variety at the final assessment date (119 DAS). Also, at this assessment date the minimum 54.44 and 55.07% severities were recorded from the varieties Gachena and Gora, respectively. According to Belachew [16] significantly highest and lowest final gall severities were recorded from local and Gora varieties, respectively, under natural infection. In general, though epidemics of the faba bean gall disease occurred in both locations, it was more severe at Mush. This might be due to the presence of more favorable environmental conditions at Mush than at Ankober during the main crop growing season. Rhaïem, et al. [17] and Tivoli, et al. [18] illustrated that disease resistance level of some genotypes in the field varies from environment to environment. 3.3. Area under Disease Progress Curve (AUDPC) Area under disease progress curves were significantly ( p ≤ 0 . 0 5 ) different among the faba bean varieties at both locations Table 3. At Lay Gorebela, the highest (2737.0%-days) AUDPC value was recorded from the variety Selale. The lowest (1981.9%-days) AUDPC value was recorded from the variety Gachena. Generally, the varieties Gachena reduced the AUDPC value by 26% over the variety Selale. Likewise, the highest ( 3374.1%-days) AUDPC value was calculated on the local faba bean variety at Mush, whereas; the lowest i.e. 2260.3 and 2274.3%-days AUDPC values were calculated on the varieties Gora and Gachena, respectively Table 3. These Gora and Gachena faba bean varieties reduced the AUDPC value by 33.01 and 32.60%, respectively as compared to the local variety. In general, AUDPC values varied among the faba bean varieties depending on the resistance levels of the varieties and it is known that AUDPC is directly related to the yield loss. In agreement with this finding, Mastewal [19] also stated the presence of significant difference among faba bean varieties against this disease in East Gojjam. 3.4. Disease Progress Rate The rate of disease progress was significantly (P<0.05) different among treatments at both locations Table 3 At Lay Gorebela, the highest (0.033, 0.032, and 0.032 gompit per day) disease progress rates were calculated for the faba bean varieties Selale, Angacha-1 and the local variety, respectively. The lowest (0.0265 gompit per day) progress rate was obtained from the variety Gachena Table 3. Likewise, at Mush, progress rates ranged from 0.02 (Gora) to 0.034 (Selale) gompit per day. Consequently, the disease progress rate of the variety Selale was faster by 1.61 and 1.57% times from the varieties Gora and Gachena, respectively. Generally, variation in the disease progress rate of the faba bean gall was clearly observed due to the difference in resistance levels of the varieties. The disease was increasing more rapidly on the variety Selale, which also showed higher level of final disease severity than the other faba bean varieties at both locations. Lower disease progress rate were calculated for the varieties Gachena and Gora, which exhibited moderately resistance reaction. 15 © 2019 Conscientia Beam. All Rights Reserved. Review of Plant Studies, 2019, 6(1): 11-20 This observation agrees with disease development rate that is affected by the resistant level of the crop which is high on susceptible and low on resistant ones [15]. 3.5. Yield and Yield Components 3.5.1. Plant Height The ANOVA revealed that varieties showed significant difference in their plant heights at both locations Table 4. At Lay Gorebela, plant heights ranged from 58.27 to 114.7 cm on the varieties Selale and CS-20-DK, respectively. This might be due to the presence of severe gall on this variety. Also, at Mush, the tallest (84.80 cm) plant height was recorded from the variety Gora. The shortest plant heights of 54.33 and 57.33 cm were recorded from the variety Selale and local variety, respectively. Table-2. Severity of “faba bean gall “at Ankober and Mush in 2014 main cropping season. Faba bean varieties Adet-Hana Angacha-1 CS-20-DK Dagm Degaga Dosha Gachena Gebelcho Gora Hachalu Lalo Moti Obse Selale Tumsa Walki Local Mean CV (%) Lay Gorebela Initial (47 DAS) Final (127 DAS) 1.58bcde 62.40cde abc 1.89 68.89abc 1.76abcde 62.80cde 1.52cde 61.96de bcde 1.64 61.48de 1.58bcde 61.30de 1.34e 56.30e 1.83abcd 64.81bcd 1.46cde 58.65de 1.90abc 62.80cde 1.59bcde 64.44cd 1.59bcde 61.30de de 1.40 63.50cd 1.99ab 72.19a 1.68abcde 60.93de 2.01ab 61.00de 2.09a 70.41ab 1.70 63.24 15.789 6.28 Mush Initial (39 DAS) Final (119 DAS) 2.36bcde 69.06cd abc 2.93 71.61bc 2.40abcde 65.02de 3.01ab 66.62cde 2.05de 63.78de 2.69abcd 62.74de 2.11de 54.44f 2.46abcde 64.15de 1.95e 55.07f 2.23cde 67.51cde 2,08abc 67.20cde 2.08de 67.36cde bcde 2.31 64.06de 2.68abcde 78.09a 2.33bcde 63.156de 2.04de 62.41e 3.1a 76.22ab 2.45 65.79 17.98 5.78 Note: DAS: Days after sowing, CV: Coefficient of variation. Table-3. The AUDPC (%-days) values and progress rates of faba bean gall disease on different faba bean varieties. Faba bean varieties Adet-Hana Angacha-1 CS-20-DK Dagm Degaga Dosha Gachena Gebelcho Gora Hachalu Lalo Moti Obse Selale Tumsa Walki Local Mean CV (%) AUDPC (%-days) Lay Gorebela Mush 2196.9defg 2965.6cd 2655.9ab 2872.4de efg 2166.6 2664.6ef cde 2362.6 3007.5cd defg 2190.0 2733.9ef efg 2165.5 2713.0ef 1961.9g 2274.3g 2228.8def 2811.1de 2016.5fg 2260.3g 2117.9efg 2798.9de 2421.7bcd 3090.5bc efg 2138.2 2867.3de cdef 2233.9 2810.8de a 2737.2 3302.3ab g 2099.1f 2693.7ef fg 2076.8 2562.1e bc 2483.4 3374.1a 2250.17 2811.99 6.70 4.58 Infection rate (r) per day Lay Gorebela Mush 0.0288cdef 0.0277bc 0.0319ab 0.0281b cdef 0.0280 0.0254bcd bcde 0.0295 0.0272bcd cdef 0.0285 0.0254bcd def 0.0283 0.0256bcd 0.0265f 0.0214e 0.0298bcd 0.0247cd 0.0269ef 0.0209e 0.0280def 0.0274bcd 0.0309abc 0.0276bc cdef 0.0280 0.0258bcd bcd 0.0299 0.0251cd a 0.0330 0.0337a def 0.0237 0.0252cd f 0.0268 0.0248cd ab 0.0318 0.0317a 0.0290 0.0260 5.3900 6.5300 Note: CV: Coefficient of variation, AUDPC: Area under disease progress curve. 16 © 2019 Conscientia Beam. All Rights Reserved. Review of Plant Studies, 2019, 6(1): 11-20 3.5.2. Number of Pods Per Plant and Seeds per Pod Faba bean varieties exhibited significant (p ≤ 0.05) variation in their pod numbers per plant. In the current study, the highest numbers pods per plant of 26.53 and 23.07 were recorded from the variety Dagm at Lay Gorebela and Mush, respectively. At this location, the lowest ( 8.27 ) number of pods per plant was obtained from the variety Gebelcho, which, in turn did not have significant difference from the varieties Adet Hana, Degaga, Gachena, Gora, Moti, Obse and Tumsa Table 4. Also, the lowest i.e. 11.53, 11.2, 11.13, 10.87 and 10.33 numbers of pods per plant were recorded from the varieties Obse, Moti, Gora, local and Gachena, respectively at Mush. However, these varieties had no significant difference from all the varieties other than the varieties Dagm and Selale in number of pods per plant Table 4. On the other hand ANOVA revealed that there were no significant (p > 0.05) differences among varieties in the number of seeds per pod at both locations, however, the range for this parameter was large. Mastewal [19] also reported the presence of non significant variation among faba bean varieties tested on this parameter. Seed number per pod ranged from 2.03 to 2.68 at Lay Gorebela, whereas at Mush it ranged from 2.27 to 3.2. Table-4. Effect of different faba bean varieties on plant height, pods per plant, seeds per pod in 2014. Faba bean varieties Adet-Hana Angacha-1 CS-20-DK Dagm Degaga Dosha Gachena Gebelcho Gora Hachalu Lalo Moti Obse Selale Tumsa Walki Local Mean CV (%) PH Lay Gorebela 88.40ab 93.73ab 114.40a 98.87ab 86.73ab 109.87a 107.47ab 81.07bc 111.40a 108.27ab 101.73ab 95.40ab 105.73ab 58.27c 107.20ab 109.07ab 93.60ab 98.31 17.33 Mush 61.40cd 75.13abc 77.93ab 71.8abc 80.60ab 76.53ab 75.67ab 79.40ab 84.80a 83.87ab 71.40bc 80.20ab 83.20ab 54.33d 81.07ab 76.13ab 57.33d 74.58 10.79 PPP Lay Gorebela 15.00defg 15.35defg 23.20abc 26.53a 11.80efg 19.00bcde 11.47fg 8.27g 13.93efg 18.80bcdef 23.07abc 12.27efg 12.27efg 24.20ab 13.20efg 21.87abcd 16.47cdef 16.86 26.29 Mush 12.47bc 13.67bc 14.00bc 23.07a 16.13bc 12.47bc 10.33c 13.13bc 11.13c 15.27bc 15.40bc 11.20c 11.53c 18.40ab 13.27bc 15.13bc 10.87c 13.97 27.44 SPP Lay Gorebela 2.05 2.09 2.04 2.17 2.64 2.04 2.14 2.25 2.46 2.05 2.43 2.68 2.35 2.30 2.15 2.03 2.06 2.22 13.69 Mush 2.27 2.67 3.20 2.60 2.53 2.67 2.60 2.60 2.33 2.60 2.70 2.67 2.73 2.47 2.27 2.60 2.53 2.61 11.14 Note: CV: Coefficient of variation, LSD: Least significant difference, PH: Plant height, PPP: Pods per plant, SPP: Seeds per pod. 3.6. Grain Yield and Hundred Seed Weight Faba bean varieties showed significant (p ≤ 0.05) variation in their grain yield and hundred sed weight at both locations Table 5. From the beginning, it should be emphasized that the differences in grain yield among the varieties could be explained not only by differences in the levels of disease occurrence but also in the inherent potential yields of the varieties. The highest (4.41 t ha-1) grain yield was gained from variety Gora, whereas the lowest (2.26 t ha-1) grain yield was from variety Selale at Lay Gorebela. Also, the highest yields of 3.77, 3.74, 3.70, 3.65 and 3.59 t ha-1 were obtained from the varieties Gora, Gebelcho, Degaga, Gachena and Walki, respectively, at Mush. The lowest grain yields of 1.71 and 1.91 t ha-1 were obtained from the local variety and the variety Selale, respectively. Mastewal [19] confirmed that lowest grain yield was obtained from local faba bean variety compared to other varieties tested against faba bean gall disease. Furthermore, the ranking of the varieties for yield may change, should the varieties be exposed to higher disease severity. This is mainly due to varying levels of tolerance that is expected in different faba bean varieties. 17 © 2019 Conscientia Beam. All Rights Reserved. Review of Plant Studies, 2019, 6(1): 11-20 At Lay Gorebela, the lowest grain weight of 29.1 g was recorded from the variety Selale. On the contrary, the variety Gora had a hundred seed weight of 84.50 g. and did not show significant differences from the varieties Gachena, Obse and Tumsa in hundred seed weigh. Similarly, the lowest i.e. 31.07, 33.4, 34.83, and 35.07 g hundred seed weight were recorded from varieties Dagm, Lalo, Selale and local, respectively, at Mush. On the other hand, the highest (76.77 g) grain weight was recorded for the variety Gora. 3.7. Association of Disease Parameters with Yield Correlation analysis showed that faba ba bean gall severity had moderate and high negative correlation (r = 0.38 and r = -0.62) with yields at Lay Gorebela and Mush, respectively Table 6. Also, grain yield showed significant and negative correlations (r = -0.39 and r = -0.63) with AUDPC values at Lay Gorebela and Mush, respectively. Sahar, et al. [20] also reported that the higher AUDPC values were accompanied by lower yields. On the other hand, the correlations observed between disease parameters (severities and AUDPC values) were positive and highly significant (p ≤ 0.01).This might indicated the terminal disease severity and AUDPC were very important in determining the extent of losses in yield and yield components and the observed levels of the disease had a considerable adverse effect on grain yield of the crop. Table-5. Yields and hundred seed weights of faba bean varieties tested at Lay Gorebela and Mush in the 2014 main cropping season. Faba bean varieties Adet-Hana Angacha-1 CS-20-DK Dagm Degaga Dosha Gachena Gebelcho Gora Hachalu Lalo Moti Obse Selale Tumsa Walki Local Mean CV (%) Grain yield (tons ha-1) Lay Gorebela Mush 2.35ef 2.11cd 2.65def 2.73bc cdef 3.14b 3.17ab cdef 3.2b 2.06cd cdef 2.71 3.70a abcd 3.61 3.29ab ab 4.02 3.65a cdef 2.82 3.74a 4.41a 3.77a 3.89abc 3.37ab 3.28abcdef 3.07ab 2.94bcdef 3.31ab 3.52abcde 3.47ab f 2.26 1.91d abcd 3.58 3.37ab abcd 3.64 3.59a ef 2.37 1.71d 2.24 3.06 22.55 15.97 HSW (g) Lay Gorebela 47.67de 44.87de 52.53d 30.73fg 50.20de 63.87c 79.40ab 67.63c 84.50a 51.93de 30.27fg 71.03bc 74.83abc 29.10g 79.07ab 71.53bc 41.10ef 57.07 11.87 Mush 51.43e 43.07g 46.00fg 31.07h 46.37fg 58.33d 70.43b 67.93c 76.77a 48.23ef 33.40h 68.83c 67.70c 34.83h 65.60c 67.93c 35.07h 50.98 5.25 Note: CV: Coefficient of variation, LSD: Least significant difference, HSW: Hundred seed weight. 4. CONCLUSION AND RECOMMENDATION In conclusion, the present study revealed the existence of variability among faba bean varieties against faba bean gall disease and grain yield at both locations. The lowest PSI, AUDPC and infection rate were recorded from variety Gachena (at Lay Gorebela) and varieties Gora and Gachena (at Mush). Regarding grain yield, the highest grain yield was obtained from varieties Gora, Gebelcho, Degaga, Gachena and Walki (at Mush) and from varieties Gora and Gachena (at Ankober). Conversely, the lowest grain yield was harvested from variety Selale (at Lay Gorebela) and varieties Selale and local (at Mush). Moreover, yield of faba bean correlated negatively and significantly with AUDPC and final severity at both locations, whereas, AUDPC and severity associated positively and significantly from each other. From this study it can be concluded that relatively resistant and high yielder varieties can be used in combination with other control measures. Therefore, in the future, researches on integration of resistance and high yielder varieties with other management options should be conducted. 18 © 2019 Conscientia Beam. All Rights Reserved. Review of Plant Studies, 2019, 6(1): 11-20 Table-6. Correlation coefficients (r) for disease parameters and crop yields in 2014 main cropping season. A) Lay Gorebela Parameters PH PPP SPP HSW YLD PSI PH -----PPP 0.183ns -----SPP 0.050ns 0.126ns -----HSW 0.347* 0.492** 0.081ns -----Yld 0.344* 0.030ns 0.065ns 0.376** -----PSI -0.336* -0.071ns -0.215ns -0.480** -0.381** -----AUDPC -0.494** -0.310* -0.164ns -0.661** -0.390** 0.703** B) Mush Parameters PH PPP SPP HSW YLD PSI PH -----PPP 0.001ns -----SPP 0.108ns 0.060ns -----HSW 0.460** 0.477** 0.103ns -----YLD 0.788** 0.212ns 0.115ns 0.632** -----PSI -0.623** -0.143ns -0.135ns -0.673** -0.622** -----AUDPC -0.603** -0.184ns -0.115ns -0.726** -0.629** 0.810** PH: Plant height, PPP: Pod per plant, SPP: Seed per pod, HSW: Hundred seed weight, YLD: Yield, PSI: Present severity index, AUDPC: Area under disease progress curve,*: refers to mean square values significant at α=0.05, **: refers to mean square values significant at α=0.01, ns: refers to mean square values not significant at α=0.05. Funding: This study was financed by International Centre for Agricultural Research in the Dray Areas (ICARDA) through ADA project (Austrian Development Agency). Competing Interests: The authors declare that they have no competing interests. Acknowledgement: The authors are thankful to Daniel Admasu, Zerihun Kebede, Kibnesh Girma and Fikrey Tesfaye for assistance in field work, laboratory work and write up. They thank Holleta Agricultural Research Center for providing us with faba bean seeds. REFERENCES [1] Central Statistical Agency (CSA), "Report on area and production of major crops (private peasant holdings, meher season)," Statistical Bulletin, vol. 1, pp. 10-14, 2014. [2] S. Samuel, S. Ahmed, C. Fininsa, M. M. Abang, and P. K. Sakhuja, "Survey of chocolate spot (Botrytis fabae) disease of faba bean (Vicia faba L.) and assessment of factors influencing disease epidemics in Northern Ethiopia," Crop Protection, vol. 27, pp. 1457-1463, 2008. [3] B. Bitew and W. 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