Mixtures composed of five wheat cultivars,Jingshuang 16,Jing 411,Jingdong 8,Lunxuan 987,and Baofeng 104,with different levels of resistance against powdery mildew were tested for their potential containment of the dis...Mixtures composed of five wheat cultivars,Jingshuang 16,Jing 411,Jingdong 8,Lunxuan 987,and Baofeng 104,with different levels of resistance against powdery mildew were tested for their potential containment of the disease development in the field and for the influence on grain yield and the content of crude protein in the years 2007 and 2010.The plots were inoculated artificially with mixed isolates collected in the fields and propagated in the greenhouse and the disease was scored in 7 d interval during the two growing seasons.It was indicated that certain combinations,e.g.,Jingdong 8:Lunxuan 987,Jingdong 8:Baofeng 104,and Jing 411:Jingdong 8:Baofeng 104,showed positive efficacy on the mildew.The cultivar combinations tested in 2007 showed increase of grain yield,while most of the combinations tested in 2010 did not show the increase.The differences of the increases or decreases were not statistically significant except combinations Jing 411:Jingdong 8:Baofeng104,Jingshuang16:Jingdong8:Lunxuang 987 and Jingshuang 16:Jingdong 8:Lunxuan 987:Baofeng 104,which showed the decrease of the grain yield.The mixtures did not show influence on the content of crude protein in grain.More cultivar combinations need to be tested.展开更多
研究紫外线对小麦叶锈病病菌12-5-1384-1菌株和其诱变菌株1384-B-10-1孢子萌发率和流行学因素的影响。结果表明,紫外线对这2个菌株的影响表现一致,紫外线处理均使夏孢子萌发率降低,潜育期延长,侵染效率、产孢量及病情发展曲线下面积(are...研究紫外线对小麦叶锈病病菌12-5-1384-1菌株和其诱变菌株1384-B-10-1孢子萌发率和流行学因素的影响。结果表明,紫外线对这2个菌株的影响表现一致,紫外线处理均使夏孢子萌发率降低,潜育期延长,侵染效率、产孢量及病情发展曲线下面积(area under disease-progress curve,简称AUDPC)显著下降,病斑扩展率最大值下降;紫外线处理后,与原始菌株相比,诱变菌株夏孢子的相对萌发率较高,侵染效率提高,病斑扩展率最大值延迟,产孢量和AUDPC升高。以上结果表明,诱变菌株对紫外线的容忍度比原始菌株大,即诱变菌株更适宜在紫外线越来越强的自然环境中生存。展开更多
Faba bean is suffered with many biotic and abiotic factors. Chocolate spot disease, caused by Botrytis fabae is one of the biotic factors limiting yields of this crop resulting in yield losses up to 68% in Ethiopia. T...Faba bean is suffered with many biotic and abiotic factors. Chocolate spot disease, caused by Botrytis fabae is one of the biotic factors limiting yields of this crop resulting in yield losses up to 68% in Ethiopia. The experiment was conducted during 2020/2021 cropping season at Tach Gayint district, Ethiopia to determine the integration of faba bean varieties and fungicide rates on reducing chocolate spot disease. The experiment consisted of 12 treatments, viz. three faba bean varieties and four rate of Mancozeb fungicide in factorial arrangement. The experiment was laid out as randomized complete block design (RCBD) with three replications. Data was collected and analyzed. Results indicated that, disease incidence was reached at maximum percentage in all treatments on the last dates of assessment. But treatments were significantly difference in severity level. The least disease severity was recorded from varieties treated by 3.5 kg/ha of Mancozeb 80% WP with mean values Walki (12.7%), and (18.1% and 20.8%) on Gora and local variety respectively at the final dates of disease assessment. Similarly, the reduced AUDPC was also recorded from varieties treated by 3.5 kg/ha of Mancozeb 80% WP with mean values Walki (371.8% unit/day) and (539% and 686.4% days) on varieties Gora, and Local respectively. Whereas the maximum disease severity and AUDPC were obtained from unsprayed plots. Based on the results obtained, variety Walki treated with Mancozeb 80% WP at rate of 2.5 kg/ha and 3.5 kg/ha were effective to reduce the effect of chocolate spot disease for the study area.展开更多
Lr34 is a vital gene in developing resistance to leaf rust, stripe rust, and powdery mildew of wheat. Providing simultaneous resistance to various pathogens has made this gene valuable in breeding for wheat resistance...Lr34 is a vital gene in developing resistance to leaf rust, stripe rust, and powdery mildew of wheat. Providing simultaneous resistance to various pathogens has made this gene valuable in breeding for wheat resistance to many diseases. The present study investigates the csLV34 marker’s capability in diagnosing this locus in130 wheat commercial cultivars and advanced wheat lines from Iran, and assesses the impact of this gene on disease severity in field conditions. To assess the reactions of cultivars and lines which contained Lr34 under epidemic conditions of leaf rust, these cultivars were cultivated during the 2009 and 2010 cropping season. Of the 130 studied cultivars, 43 contained Lr34. Cultivars that were selected and studied in stress conditions had the most frequent presence of Lr34. It can be concluded that this gene plays a vital role in increasing the tolerance of cultivars under stress conditions. Lr34 seems to cause active transition of materials out of the cell. In addition to being resistant to several important diseases of wheat, Lr34 can increase tolerance to stresses such as salinity. Considering the calculated value for AUDPC (3%-440%/d) in cultivars containing Lr34, it seems that some cultivars contained additional resistance genes. The rate of infection in all cultivars, when presence of Lr34 was detected through the molecular marker, was lower than in other cultivars. Field results confirmed the results of the analysis using the csLV34b molecular marker.展开更多
The responses of eight genetically improved and eight local cassava varieties to cassava mosaic disease (CMD) were evaluated under field conditions at two sites, in Eastern Kasa?, region of the DR-Congo). The varietie...The responses of eight genetically improved and eight local cassava varieties to cassava mosaic disease (CMD) were evaluated under field conditions at two sites, in Eastern Kasa?, region of the DR-Congo). The varieties were planted using randomized complete block design with three replications. The rate of cuttings sprouted varied significantly from variety to variety and from location to location. Local varieties were severely infected than improved varieties throughout the trial period. In general, the level of CMD incidence for genetically improved varieties was below 15% while it reached 100% for the local cassava varieties six months after planting (MAP). This trend was also observed for the CMD severity and gravity. The mean scores for CMD severity were 2 and 3.6 for genetically improved and local varieties, respectively at 6 MAP. CMD gravity for improved varieties was below 21% for genetically improved varieties and exceeded 85% for local varieties at the end of trials. Area Under the Severity index Progress Curve (AUSiPC) and Area Under Disease Progress Curve (AUDPC) estimates confirmed that improved varieties were moderately infested comparatively to local varieties. Molecular analysis is being conducted to determine the genetic variability and complexity of the cassava mosaic virus strains involved.展开更多
Fusarium wilt is a major disease of watermelon (</span><i><span style="font-family:Verdana;">Citrullus</span></i> <i><span style="font-family:Verdana;">lan...Fusarium wilt is a major disease of watermelon (</span><i><span style="font-family:Verdana;">Citrullus</span></i> <i><span style="font-family:Verdana;">lanatus</span></i><span style="font-family:Verdana;">) caused by </span><i><span style="font-family:Verdana;">Fusarium</span></i> <i><span style="font-family:Verdana;">oxysporum</span></i><span style="font-family:Verdana;"> f. sp. </span><i><span style="font-family:Verdana;">niveum</span></i><span style="font-family:Verdana;"> (</span><i><span style="font-family:Verdana;">Fon</span></i><span style="font-family:Verdana;">). Use of host resistance is the most </span><span style="font-family:Verdana;">effective management strategy for the disease, and a major objective for breeding programs. Screening assays rely on the ability to discriminate resistant and susceptible genotypes in segregating populations. However, complex</span> <span><span style="font-family:Verdana;">interactions between </span><i><span style="font-family:Verdana;">Fon</span></i><span style="font-family:Verdana;"> and the soil environment can influence symptom development and disease severity rating. In the current study, severity of Fusarium wilt (race 1) in sand-peat (1:1 v/v), sand-perlite (1:1), sand-peat-vermiculite (4:1:1), </span></span><span style="font-family:Verdana;">peat-perlite (1:1) and Fafard 3B potting media was compared among five watermelon cultivars: Calhoun Gray (resistant), </span><span style="font-family:Verdana;">SunSugar (resistant), Allsweet (moderately resistant), Sugar Baby (susceptible) and Charleston Gray (susceptible). Plant biomass (average dry weight/plant) was lowest in peat-perlite (1.67</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">g) </span><span style="font-family:""><span style="font-family:Verdana;">and sand-peat (2.16 g), and was significantly different (</span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;"> = 0.05) from that of sand-perlite (3.48 g), sand-peat-vermiculite (4.94 g) and Fafard 3B (6.90 g). Conversely, disease severity [area under disease progress curve (AUDPC)] across cultivars was significantly higher in peat-perlite (AUDPC = 62.96) and sand-peat (AUDPC = 40.87), than in sand-perlite (AUDPC = 11.55), sand-peat-vermiculite (AUDPC = 10.67) and Fafard 3B (AUDPC = 9.29). Consistent discrimination (</span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;"> = 0.05) of resistant and susceptible cultivars was realized in sand-peat-vermiculite and Fafard 3B, but was not possible in peat-perlite, sand-peat and sand-perlite. Collectively, these findings support suitability of sand-peat-vermiculite and Fafard 3B for routine screening of Fusarium wilt resistance in watermelon.展开更多
Potato (Solanum tuberosum) early blight, caused by Alternaria solani is one of the most destructive fungal foliar diseases. This research was done in order to study methods comparison of evaluation by culture filtrate...Potato (Solanum tuberosum) early blight, caused by Alternaria solani is one of the most destructive fungal foliar diseases. This research was done in order to study methods comparison of evaluation by culture filtrate of A. solani in in vitro condition for selecting resistance cultivars to early blight. Plantlets of potato viruse free were obtained from the National plant gene bank of Iran, and were inoculated in vitro methods with a culture filtrate of A. solani. In in vitro selection by droplet of culture filtrate method, leaflet received a 10 μl droplet of the A. solani culture filtrate and in in vitro selection by direct using of culture filtrate method, plantlets were placed in test tubes that include 5 μl A. solani culture filtrate. The experimental design was factorial on basis of completely randomized design (CRD) with two factors, three replications and six genotypes. During droplet method assay, the A. solani symptoms appeared 1 - 2 days until 6 days and during direct method they appeared 2 - 3 days until 6 days. The AUDPC values were submitted to the analysis of varience (ANOVA) and AUDPC means were compared by using Duncan test (α = 0.01%). In each method, significant difference among potato cultivars was observed for disease to early blight (p < 0.01). Results show that casmos cultivar is susceptible for resistance to early blight and in vitro methods experiment had the same result.展开更多
基金supported by the National Basic Research Program of China(2006CB100203 and 2011CB100403)the Key Technology R & D Program of China during the 11th Five-Year Plan period(2006BAD08A05)the Special Fund for Agro-Scientific Research in the Public Interest,China(3-15)
文摘Mixtures composed of five wheat cultivars,Jingshuang 16,Jing 411,Jingdong 8,Lunxuan 987,and Baofeng 104,with different levels of resistance against powdery mildew were tested for their potential containment of the disease development in the field and for the influence on grain yield and the content of crude protein in the years 2007 and 2010.The plots were inoculated artificially with mixed isolates collected in the fields and propagated in the greenhouse and the disease was scored in 7 d interval during the two growing seasons.It was indicated that certain combinations,e.g.,Jingdong 8:Lunxuan 987,Jingdong 8:Baofeng 104,and Jing 411:Jingdong 8:Baofeng 104,showed positive efficacy on the mildew.The cultivar combinations tested in 2007 showed increase of grain yield,while most of the combinations tested in 2010 did not show the increase.The differences of the increases or decreases were not statistically significant except combinations Jing 411:Jingdong 8:Baofeng104,Jingshuang16:Jingdong8:Lunxuang 987 and Jingshuang 16:Jingdong 8:Lunxuan 987:Baofeng 104,which showed the decrease of the grain yield.The mixtures did not show influence on the content of crude protein in grain.More cultivar combinations need to be tested.
文摘研究紫外线对小麦叶锈病病菌12-5-1384-1菌株和其诱变菌株1384-B-10-1孢子萌发率和流行学因素的影响。结果表明,紫外线对这2个菌株的影响表现一致,紫外线处理均使夏孢子萌发率降低,潜育期延长,侵染效率、产孢量及病情发展曲线下面积(area under disease-progress curve,简称AUDPC)显著下降,病斑扩展率最大值下降;紫外线处理后,与原始菌株相比,诱变菌株夏孢子的相对萌发率较高,侵染效率提高,病斑扩展率最大值延迟,产孢量和AUDPC升高。以上结果表明,诱变菌株对紫外线的容忍度比原始菌株大,即诱变菌株更适宜在紫外线越来越强的自然环境中生存。
文摘Faba bean is suffered with many biotic and abiotic factors. Chocolate spot disease, caused by Botrytis fabae is one of the biotic factors limiting yields of this crop resulting in yield losses up to 68% in Ethiopia. The experiment was conducted during 2020/2021 cropping season at Tach Gayint district, Ethiopia to determine the integration of faba bean varieties and fungicide rates on reducing chocolate spot disease. The experiment consisted of 12 treatments, viz. three faba bean varieties and four rate of Mancozeb fungicide in factorial arrangement. The experiment was laid out as randomized complete block design (RCBD) with three replications. Data was collected and analyzed. Results indicated that, disease incidence was reached at maximum percentage in all treatments on the last dates of assessment. But treatments were significantly difference in severity level. The least disease severity was recorded from varieties treated by 3.5 kg/ha of Mancozeb 80% WP with mean values Walki (12.7%), and (18.1% and 20.8%) on Gora and local variety respectively at the final dates of disease assessment. Similarly, the reduced AUDPC was also recorded from varieties treated by 3.5 kg/ha of Mancozeb 80% WP with mean values Walki (371.8% unit/day) and (539% and 686.4% days) on varieties Gora, and Local respectively. Whereas the maximum disease severity and AUDPC were obtained from unsprayed plots. Based on the results obtained, variety Walki treated with Mancozeb 80% WP at rate of 2.5 kg/ha and 3.5 kg/ha were effective to reduce the effect of chocolate spot disease for the study area.
文摘Lr34 is a vital gene in developing resistance to leaf rust, stripe rust, and powdery mildew of wheat. Providing simultaneous resistance to various pathogens has made this gene valuable in breeding for wheat resistance to many diseases. The present study investigates the csLV34 marker’s capability in diagnosing this locus in130 wheat commercial cultivars and advanced wheat lines from Iran, and assesses the impact of this gene on disease severity in field conditions. To assess the reactions of cultivars and lines which contained Lr34 under epidemic conditions of leaf rust, these cultivars were cultivated during the 2009 and 2010 cropping season. Of the 130 studied cultivars, 43 contained Lr34. Cultivars that were selected and studied in stress conditions had the most frequent presence of Lr34. It can be concluded that this gene plays a vital role in increasing the tolerance of cultivars under stress conditions. Lr34 seems to cause active transition of materials out of the cell. In addition to being resistant to several important diseases of wheat, Lr34 can increase tolerance to stresses such as salinity. Considering the calculated value for AUDPC (3%-440%/d) in cultivars containing Lr34, it seems that some cultivars contained additional resistance genes. The rate of infection in all cultivars, when presence of Lr34 was detected through the molecular marker, was lower than in other cultivars. Field results confirmed the results of the analysis using the csLV34b molecular marker.
文摘The responses of eight genetically improved and eight local cassava varieties to cassava mosaic disease (CMD) were evaluated under field conditions at two sites, in Eastern Kasa?, region of the DR-Congo). The varieties were planted using randomized complete block design with three replications. The rate of cuttings sprouted varied significantly from variety to variety and from location to location. Local varieties were severely infected than improved varieties throughout the trial period. In general, the level of CMD incidence for genetically improved varieties was below 15% while it reached 100% for the local cassava varieties six months after planting (MAP). This trend was also observed for the CMD severity and gravity. The mean scores for CMD severity were 2 and 3.6 for genetically improved and local varieties, respectively at 6 MAP. CMD gravity for improved varieties was below 21% for genetically improved varieties and exceeded 85% for local varieties at the end of trials. Area Under the Severity index Progress Curve (AUSiPC) and Area Under Disease Progress Curve (AUDPC) estimates confirmed that improved varieties were moderately infested comparatively to local varieties. Molecular analysis is being conducted to determine the genetic variability and complexity of the cassava mosaic virus strains involved.
文摘Fusarium wilt is a major disease of watermelon (</span><i><span style="font-family:Verdana;">Citrullus</span></i> <i><span style="font-family:Verdana;">lanatus</span></i><span style="font-family:Verdana;">) caused by </span><i><span style="font-family:Verdana;">Fusarium</span></i> <i><span style="font-family:Verdana;">oxysporum</span></i><span style="font-family:Verdana;"> f. sp. </span><i><span style="font-family:Verdana;">niveum</span></i><span style="font-family:Verdana;"> (</span><i><span style="font-family:Verdana;">Fon</span></i><span style="font-family:Verdana;">). Use of host resistance is the most </span><span style="font-family:Verdana;">effective management strategy for the disease, and a major objective for breeding programs. Screening assays rely on the ability to discriminate resistant and susceptible genotypes in segregating populations. However, complex</span> <span><span style="font-family:Verdana;">interactions between </span><i><span style="font-family:Verdana;">Fon</span></i><span style="font-family:Verdana;"> and the soil environment can influence symptom development and disease severity rating. In the current study, severity of Fusarium wilt (race 1) in sand-peat (1:1 v/v), sand-perlite (1:1), sand-peat-vermiculite (4:1:1), </span></span><span style="font-family:Verdana;">peat-perlite (1:1) and Fafard 3B potting media was compared among five watermelon cultivars: Calhoun Gray (resistant), </span><span style="font-family:Verdana;">SunSugar (resistant), Allsweet (moderately resistant), Sugar Baby (susceptible) and Charleston Gray (susceptible). Plant biomass (average dry weight/plant) was lowest in peat-perlite (1.67</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">g) </span><span style="font-family:""><span style="font-family:Verdana;">and sand-peat (2.16 g), and was significantly different (</span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;"> = 0.05) from that of sand-perlite (3.48 g), sand-peat-vermiculite (4.94 g) and Fafard 3B (6.90 g). Conversely, disease severity [area under disease progress curve (AUDPC)] across cultivars was significantly higher in peat-perlite (AUDPC = 62.96) and sand-peat (AUDPC = 40.87), than in sand-perlite (AUDPC = 11.55), sand-peat-vermiculite (AUDPC = 10.67) and Fafard 3B (AUDPC = 9.29). Consistent discrimination (</span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;"> = 0.05) of resistant and susceptible cultivars was realized in sand-peat-vermiculite and Fafard 3B, but was not possible in peat-perlite, sand-peat and sand-perlite. Collectively, these findings support suitability of sand-peat-vermiculite and Fafard 3B for routine screening of Fusarium wilt resistance in watermelon.
文摘Potato (Solanum tuberosum) early blight, caused by Alternaria solani is one of the most destructive fungal foliar diseases. This research was done in order to study methods comparison of evaluation by culture filtrate of A. solani in in vitro condition for selecting resistance cultivars to early blight. Plantlets of potato viruse free were obtained from the National plant gene bank of Iran, and were inoculated in vitro methods with a culture filtrate of A. solani. In in vitro selection by droplet of culture filtrate method, leaflet received a 10 μl droplet of the A. solani culture filtrate and in in vitro selection by direct using of culture filtrate method, plantlets were placed in test tubes that include 5 μl A. solani culture filtrate. The experimental design was factorial on basis of completely randomized design (CRD) with two factors, three replications and six genotypes. During droplet method assay, the A. solani symptoms appeared 1 - 2 days until 6 days and during direct method they appeared 2 - 3 days until 6 days. The AUDPC values were submitted to the analysis of varience (ANOVA) and AUDPC means were compared by using Duncan test (α = 0.01%). In each method, significant difference among potato cultivars was observed for disease to early blight (p < 0.01). Results show that casmos cultivar is susceptible for resistance to early blight and in vitro methods experiment had the same result.