Response of Sorghum Accessions from Four African Countries against &lt;i&gt;Colletotrichum sublineolum&lt;/i&gt;, Causal Agent of Sorghum Anthracnose

Globally, the foliar phase of anthracnose is one of the most destructive diseases of sorghum. In most cases, anthracnose resistance screening relies on the use of a spore suspension. This method is usually conducted after sundown and when there is the possibility of dew formation the following morning. Using a spore suspension for sorghum anthracnose field evaluation in College Station, Texas over five years (1996, 1997, 1999-2001) yielded inconsistent linkage results and failed to identify any closely linked molecular markers. For large scale screening of sorghum germplasm for anthracnose (Colletotrichum sublineolum) resistance, plants are inoculated in the field or in the green house at either 30 d after planting or at the 8-10 leaf-stage. In field inoculation, the use of C. sublineolum-colonized sorghum grains was shown to be the most efficient and effective in identifying resistant sources. For effective, efficient, fast and accurate infection, approximately 10-20 seeds are placed in each plant leaf whorl and it takes about 16.7 kg of colonized grains to cover a 0.4 ha area. In the greenhouse, though colonized grains are equally effective, spray inoculation is preferred for easy and uniform coverage. Using this method of inoculum preparation, spore suspension was extracted and sprayed (106 conidia·ml-1), followed by 10 hr/d misting for 30 sec at 30-45 min interval continuously for a period of one month resulted in effective infection.

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Response to Anthracnose and Germination Rate of Colletotrichum Sublineola Acervuli of Greenhouse-Grown Sorghum

Journal of Agriculture and Crops ◽

10.32861/jac.512.266.269 ◽

2019 ◽

pp. 266-269

Author(s):

Louis K. Prom Thomas Isakeit ◽

Ghada Radwan

Keyword(s):

Germination Rate ◽

Causal Agent ◽

Sorghum Anthracnose ◽

The Difference ◽

Inhibitor Compounds ◽

Sorghum Germplasm

Colletotrichum sublineola, the causal agent of sorghum anthracnose, infects all above ground parts of the crop. The most pronounced phase of the disease is its foliar phase. In this study, 10 sorghum lines with checks were evaluated in the greenhouse for resistance against C. sublineola. Acervuli germination rate within infected leaves was also recorded. All the 10 sorghum lines along with checks BTX623, TAM428, and PI609251 were susceptible and as expected, SC748 was resistant. Variation among the lines for acervuli germination rate was observed; TAM428 and 1110248 recorded the highest percentage (98.3%) while PI609251 exhibited the lowest rate of acervuli germination (33.3%). Conidia produced from germinating acervuli are critical to the distribution and spread of the disease. However, conidia produced within the acervuli do not usually germinate due to the presence of self-inhibitor compounds. Thus, these self-inhibitors that may occur in the acervuli could explain the difference in levels of susceptibility among sorghum germplasm.

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Pathotypes of Colletotrichum sublineolum in Arkansas

Plant Disease ◽

10.1094/pdis-92-10-1415 ◽

2008 ◽

Vol 92 (10) ◽

pp. 1415-1420 ◽

Cited By ~ 20

Author(s):

J. W. Moore ◽

M. Ditmore ◽

D. O. TeBeest

Keyword(s):

Grain Sorghum ◽

Inbred Lines ◽

The State ◽

Delta Region ◽

Breeding Lines ◽

Colletotrichum Sublineolum ◽

Sorghum Anthracnose ◽

Sorghum Breeding

Sorghum anthracnose, caused by Colletotrichum sublineolum, is widely distributed in most grain sorghum-producing areas in Arkansas, and localized epidemics continue to occur across the state. The objectives of this research were to determine the number of pathotypes of C. sublineolum in Arkansas and to determine where these pathotypes are located within the state. Ninety-eight isolates were collected from research stations and production fields located in the Delta region of Arkansas from 2003 through 2005 and were tested for virulence to eight differential grain sorghum breeding lines. Of these, 11 isolates produced conflicting and unreliable results and were excluded from further analysis. Among the remaining 87 isolates, 13 pathotypes were identified. Eleven of these pathotypes were previously unreported, with 53% of the isolates consisting of pathotype 9. Pathotype 9 was distinguished from all other pathotypes by its virulence to all eight differential lines. Pathotype diversity appeared to be more closely associated with the year than with the locations where isolates were collected. Although all host differential lines were susceptible to at least 50% of the isolates evaluated, inbred lines SC326-6, TAM428, and TX2536 were susceptible to more than 90% of the 87 isolates evaluated. These results showed that the C. sublineolum populations in Arkansas are diverse based on the comparisons of pathogenicity to previously published host differentials, and it appears that these field populations varied from year to year.

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Distribution and Importance of Sorghum Anthracnose (Colletotrichum sublineolum) in Southwestern and Western Ethiopia

Plant Pathology Journal ◽

10.3923/ppj.2016.75.85 ◽

2016 ◽

Vol 15 (3) ◽

pp. 75-85 ◽

Cited By ~ 5

Author(s):

Binyam Tsedaley ◽

Girma Adugna ◽

Fikre Lemessa

Keyword(s):

Colletotrichum Sublineolum ◽

Sorghum Anthracnose ◽

Western Ethiopia

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In vitro antimicrobial activity of aqueous extracts from Lentinula edodes isolates against Colletotrichum sublineolum and Xanthomonas axonopodis pv. Passiflorae

Summa Phytopathologica ◽

10.1590/0100-5405/1995 ◽

2015 ◽

Vol 41 (1) ◽

pp. 13-20 ◽

Cited By ~ 3

Author(s):

Nivea Maria Tonucci-Zanardo ◽

Sérgio Florentino Pascholati ◽

Robson Marcelo Di Piero

Keyword(s):

Antimicrobial Activity ◽

Lentinula Edodes ◽

Anion Exchange Chromatography ◽

Antibacterial Activities ◽

Inhibitory Effect ◽

Exchange Chromatography ◽

Causal Agent ◽

Aqueous Extracts ◽

Colletotrichum Sublineolum

The aim of this study was to evaluate the antimicrobial activity of aqueous extracts from fruiting bodies of different isolates of Lentinula edodeson the pathogens Colletotrichum sublineolum, the causal agent of anthracnose in sorghum, and Xanthomonas axonopodispv. passiflorae, the causal agent of bacterial spot in passion fruit. Results showed that the aqueous extracts from isolates LE JAB-K and LE 95/01 significantly reduced C. sublineolumspore germination,while the isolate LE 96/22 was the only one to inhibit the pathogen mycelial growth. However, all L. edodesisolates showed inhibitory effect on C. sublineolumappressorium formation. Regarding X. axonopodispv. passiflorae, the aqueous extracts from all L. edodesisolates significantly reduced the in vitromultiplication of the bacterium. However, antimicrobial activity was lost when the extracts were autoclaved, demonstrating their thermolabile property. The aqueous extract from isolate LE 96/22 was also partially purified by anion exchange chromatography and fraction V exhibited high inhibitory activity on the in vitromycelial growth of C. sublineolum, while the multiplication of X. axonopodispv. passifloraewas inhibited by fractions IV, V and VII. Thus, L. edodesisolates were shown to produce compounds exhibiting antifungal and antibacterial activities against phytopathogens, which are mainly concentrated in fraction V.

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Development of Anthracnose on Grain Sorghum Hybrids Inoculated with Recently Described Pathotypes of Colletotrichum sublineolum Found in Arkansas

Plant Disease ◽

10.1094/pdis-94-5-0589 ◽

2010 ◽

Vol 94 (5) ◽

pp. 589-595 ◽

Cited By ~ 4

Author(s):

J. W. Moore ◽

M. Ditmore ◽

D. O. TeBeest

Keyword(s):

Disease Severity ◽

Host Resistance ◽

Field Experiments ◽

Grain Sorghum ◽

Yield Parameters ◽

Colletotrichum Sublineolum ◽

Progress Curve ◽

Sorghum Anthracnose ◽

High Yields ◽

Different Levels

Sorghum anthracnose, caused by Colletotrichum sublineolum, is found in most grain-sorghum-producing areas, including Arkansas. Yield losses can be severe in susceptible sorghum hybrids, suggesting that host resistance will continue to be critical for maintaining high yields. However, genetic control is often unsuccessful because of haplotype and pathotype variability within the C. sublineolum population. The objective of this research was to assess the levels of resistance of selected grain sorghum hybrids to isolates of the recently described pathotypes of C. sublineolum found in Arkansas. Field experiments were conducted in 2005 and 2006 to evaluate the reaction of 10 sorghum hybrids to eight C. sublineolum pathotypes by collecting anthracnose severity ratings at 7, 14, 21, and 28 days after inoculation. Based on these disease severity ratings, the area under the disease progress curve was calculated for each pathotype by hybrid interaction. These data showed that different levels of resistance are available in the current grain sorghum hybrids to different pathotypes. Cargill 888Y was resistant to all pathotypes in both years. However, Asgrow A571, DEKALB DKS53-11, FFR 318, and Pioneer 84G62 were moderately susceptible to susceptible to all pathotypes tested in both years. Pathotype 9 caused the most disease on 7 of the 10 hybrids evaluated in 2005 but, in 2006, pathotypes 12 and 13 surpassed pathotype 9 for disease severity on 9 of the 10 hybrids. More work is needed to assess host resistance and the effect of sorghum anthracnose on yield parameters of grain sorghum hybrids planted in Arkansas.

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