The effect of common root rot on the yield of resistant and susceptible wheat

1996 ◽  
Vol 76 (4) ◽  
pp. 869-877 ◽  
Author(s):  
R. L. Conner ◽  
G. C. Kozub ◽  
K. L. Bailey
Keyword(s):  
Disease Severity ◽  
Root Rot ◽  
Field Tests ◽  
Cochliobolus Sativus ◽  
Common Root ◽  
Back Cross ◽  
Common Root Rot ◽  
The Impact ◽  
Disease Free

The impact of common root rot, caused by Cochliobolus sativus, on the yield of mixtures of resistant and susceptible backcross-6 derivative lines of Neepawa and Chester wheat was examined in field tests at three locations between 1991 and 1994. Different blends consisting of all 25% incremental combinations of resistant and susceptible back-cross lines within each cultivar were evaluated for disease severity and yield at root rot nurseries and disease-free sites. Significant (P < 0.05) differences in yield were often detected among cultivars. However, within cultivars, no consistent yield differences were observed among blends of resistant and susceptible lines of the same cultivar regardless of root rot severity. Key words:Cochliobolus sativus, common root rot, yield, wheat

The epidemiology of common root rot in Manitou wheat: disease progression during the growing season

1974 ◽  
Vol 52 (7) ◽  
pp. 1757-1764 ◽  
Author(s):  
P. R. Verma ◽  
R. A. A. Morrall ◽  
R. D. Tinline
Keyword(s):  
Triticum Aestivum ◽  
Disease Severity ◽  
Plant Development ◽  
Root Rot ◽  
Growing Season ◽  
Cochliobolus Sativus ◽  
Infection Rates ◽  
Common Root ◽  
Common Root Rot ◽  
Disease Rating

Common root rot in Triticum aestivum cultivar Manitou caused primarily by Cochliobolus sativus was followed during plant development in 1969, 1970, and 1971 at Matador, Saskatchewan. Plants were sampled at intervals, and three variables based mainly on the occurrence of lesions on subcrown internodes were studied: number of diseased plants per square meter; percentage of diseased plants; and disease rating which integrated percentage of diseased plants and disease severity on each plant. All variables increased with time, and the progression curves in all 3 years were hyperbolic, indicating that the increases were like those of a simple interest disease as described by Van der Plank. In two of the years, almost 100% of the plants were diseased considerably before the end of the season. The transformation proposed by Van der Plank for simple interest diseases, log10[1/(1 − x)], was applied to the percentages of diseased plants, and regressions were calculated. The slopes of these lines (infection rates) were as follows: 1969, 0.99% plants per day; 1970, 1.32%; and 1971, 1.96%. In 1969 the onset of disease was later than in 1970 and 1971, and there was correspondingly less disease at the end of the growing season.

The effect of common root rot on components of grain yield in Manitou wheat

1976 ◽  
Vol 54 (24) ◽  
pp. 2888-2892 ◽  
Author(s):  
P. R. Verma ◽  
R. A. A. Morrall ◽  
R. D. Tinline
Keyword(s):  
Triticum Aestivum ◽  
Grain Yield ◽  
Disease Severity ◽  
Root Rot ◽  
Major Effect ◽  
Kernel Weight ◽  
The Other ◽  
Cochliobolus Sativus ◽  
Common Root ◽  
Common Root Rot

The effects of common root rot (Cochliobolus sativus) on components of grain yield in naturally infected Triticum aestivum cultivar Manitou were studied at Matador, Saskatchewan, by sampling plants at maturity in 1969, 1970, and 1971. Plants were sorted into severe (SE), moderate (MO), slight (SL), and clean (CL) categories based mainly on the extent of lesions on the subcrown internodes. The number of tillers per plant, the number and weight of grains per head, the weight per head, and the 1000-kernel weight in each category were determined. Increasing values of all five components were consistently associated with decreasing disease severity. SE was mostly significantly different from the other three categories in all components except 1000-kernel weight; differences between SL and MO were usually non-significant. CL and SL were mostly significantly different for the number of tillers per plant and weight per head but non-significant for the weight and number of grains per head and 1000-kernel weight. Apparently, the major effect of common root rot was to reduce the number of tillers per plant and number of grains per head.

Effect of common root rot (Cochliobolus sativus) on yields of barley under experimental conditions in northern Syria

1997 ◽  
Vol 48 (3) ◽  
pp. 351 ◽  
Author(s):  
J. A. G. van Leur ◽  
M. Z. Alamdar ◽  
S. Khawatmi
Keyword(s):  
Root Rot ◽  
Crop Improvement ◽  
Cochliobolus Sativus ◽  
Common Root ◽  
Experimental Conditions ◽  
Yield Increase ◽  
Barley Cultivars ◽  
Common Root Rot ◽  
Improvement Programs ◽  
The Impact

The impact of Cochliobolus sativus on grain yield of different barley cultivars was studied for 3 seasons in northern Syria by comparing plots with and without artificial inoculation. Distributing oat kernels infested with C. sativus next to barley seed and inoculating seed with C. sativus conidia in a peat carrier resulted in an increase in common root rot symptoms on the subcrown internode. Subcrown internodes were shorter in inoculated than uninoculated plots. The effect of inoculation differed greatly among cultivars and years. Highest losses from the common root rot occurred under dry growing conditions, whereas a significant yield increase was noted on 2 susceptible lines grown under adequate moisture. As common root rot can reduce barley yield in unfavourable environments, the disease should be considered by crop improvement programs aimed at low-rainfall zones in Mediterranean environments.

Assessment of tolerance in wheat and barley to common root rot (Cochliobolus sativus)

1993 ◽  
Vol 73 (4) ◽  
pp. 1177-1187 ◽  
Author(s):  
L. J. Duczek ◽  
G. B. Wildermuth
Keyword(s):  
Grain Yield ◽  
Root Rot ◽  
Dry Matter ◽  
Field Tests ◽  
Cochliobolus Sativus ◽  
Disease Assessment ◽  
Growth Stages ◽  
Common Root ◽  
Common Root Rot ◽  
The Relationship

Field tests at Saskatoon, Saskatchewan, Canada indicated no evidence of tolerance to common root rot in four spring wheat cultivars. There was a relationship between increased yield losses and increasing disease. In barley, the relationship was inconsistent in four cultivars and there was evidence of tolerance or recovery in Melvin with the number of seeds per head increasing with the level of disease. In Queensland, Australia there was evidence of tolerance in the wheat cultivar Banks across two locations, but the response was not consistent in all cultivars. Dry matter loss at immature growth stages was not related to grain yield loss. The inconsistent expression of tolerance in wheat, the difficulty of assessing it, and the difficulty of distinguishing tolerance from recovery suggest that the assessment of tolerance is not a reliable method of determining the reaction to common root rot. The relationship between loss in dry matter and grain yield, as disease increased, indicates that disease assessment should continue to be based on severity of symptoms. The evidence of tolerance to common root rot in barley suggests research on tolerance should concentrate on barley instead of wheat. Key words: Cochliobolus sativus, common root rot, tolerance, wheat, barley

The impact of crop rotation and N fertilizer on common root rot of spring wheat in the Brown soil zone of western Canada

2005 ◽  
Vol 85 (3) ◽  
pp. 569-575 ◽  
Author(s):  
M. R. Fernandez ◽  
R. P. Zentner
Keyword(s):  
Fusarium Head Blight ◽  
Crop Rotation ◽  
Spring Wheat ◽  
Root Rot ◽  
Triticum Aestivum L ◽  
Cochliobolus Sativus ◽  
Common Root ◽  
Head Blight ◽  
Common Root Rot ◽  
The Impact

From 2000 to 2003, spring wheat (Triticum aestivum L.) grown in southwest Saskatchewan 1 or 2 yr after summerfallow, and after lentil (Lens culinaris Medik), flax (Linum usitatissimum L.), or continuously with and without fertilizer N was examined for root rot by measuring discoloration of subcrown internodes. Discolored tissue was also plated on nutrient agar for fungal identification. In general, common root rot was present at consistently highest levels in wheat grown after lentil, and at lowest levels in wheat grown continuously with low N fertility. The most common fungal species isolated from affected subcrown internodes were Cochliobolus sativus (Ito and Kurib.) Drechs. ex Dast. and Fusarium spp. Among the latter, F. avenaceum (Fr.) Sacc., F. equiseti (Corda) Sacc. and F. pseudograminearum O’Donnell & T. Aoki were most frequent. Fusarium avenaceum is one of the most common fusarium head blight pathogens in Saskatchewan. Wheat after lentil had one of the highest levels of this fungus. Continuous wheat grown with recommended N rates and wheat grown after summerfallow had in most cases similar root rot levels, but the frequency of fungi differed. Among the crop rotations examined, it appears that the most favourable for development of root rot in wheat was a wheat-lentil rotation. This cereal-pulse system may also contribute to a build-up of F. avenaceum inoculum for the development of fusarium head blight, an important emerging disease of cereals in Saskatchewan. Key words: Crop rotation, common root rot, wheat, Cochliobolus sativus, Fusarium, nitrogen

CONSISTENCY OF REACTION IN WHEAT LINES TO COMMON ROOT ROT

1969 ◽  
Vol 49 (2) ◽  
pp. 197-201 ◽  
Author(s):  
B. J. Sallans ◽  
R. D. Tinline
Keyword(s):  
Root Rot ◽  
Field Tests ◽  
Field Trials ◽  
Western Canada ◽  
Common Root ◽  
Common Root Rot ◽  
Pathogenic Races ◽  
High Consistency ◽  
Wheat Lines ◽  
Selection Of

Field trials distributed throughout the Prairie Provinces in western Canada indicate that any location is suitable for the selection of wheats for resistance to common root rot caused by Cochliobolus sativus, providing the level of infection is sufficiently high. Wheat lines originally selected for resistance were consistently resistant in field tests at all locations. Three of four lines were significantly more resistant than Thatcher, one of the most resistant of the commercial varieties. A high consistency in the reaction of lines selected for susceptibility also was evident in the tests. A significant interaction in the analysis of variance found between wheat lines and locations might be interpreted as indicating the occurrence of differentially pathogenic races of the fungus. Other explanations, however, are offered for this interaction effect.

Further sources of resistance to common root rot (Cochliobolus sativus) of wheat

1974 ◽  
Vol 14 (70) ◽  
pp. 666 ◽  
Author(s):  
GB Wildermuth
Keyword(s):  
Bread Wheat ◽  
Root Rot ◽  
First Record ◽  
Cochliobolus Sativus ◽  
Wheat Cultivars ◽  
Common Root ◽  
Sources Of Resistance ◽  
Common Root Rot ◽  
High Level

One cultivar of einkhorn, one cultivar of emmer, three cultivars of durum and 43 cultivars of bread wheat were screened for resistance to common root rot (Cochliobolus sativus). The emmer cultivar, Yaroslav and the white-grained bread wheat cultivars, Festival and Mexico 120, showed a high level of resistance. This is the first record of resistance in white-grained cultivars and the advantage of using whitegrained rather than red-grained cultivars as sources of resistance in Australia is indicated. It is considered that the major source of resistance in Festival, Gamut and Spica has been derived from Pusa cultivars.

scholarly journals Reaction of spring barley to common root rot under several moisture regimes: Effect on yield components, plant stand, and disease severity

1991 ◽  
Vol 71 (2) ◽  
pp. 461-472 ◽  
Author(s):  
W. E. Grey ◽  
R. E. Engel ◽  
D. E. Mathre
Keyword(s):  
Disease Severity ◽  
Root Rot ◽  
Spring Barley ◽  
Common Root ◽  
High Moisture ◽  
Common Root Rot ◽  
Moisture Regimes ◽  
Plant Stand ◽  
Effect On Yield ◽  
Disease Pressure

The reaction of spring barley to common root rot and its effect on yield components, plant stand, and disease severity was studied under several moisture regimes. Infection of barley from natural soil inoculum, primarily Cochliobolus sativus, was augmented with inoculum of C. sativus or Fusarium culmorum to insure uniform disease pressure during plant development. In one study during the 1986 and 1987 growing seasons, a line-source sprinkler irrigation system was utilized to establish a soil moisture gradient from a high-moisture regime receiving both irrigation water and rainfall to a dryland regime receiving only rainfall. In 1986, a second study was carried out to examine the effect of soil moisture at three locations that differed in annual precipitation. Plant emergence and harvestable tillers were reduced by C. sativus in both studies as compared to the noninoculated controls. Grain yield loss was associated with C. sativus and low plant density under drought but not under moderate to high moisture conditions. In the irrigated moisture regimes, moderate and high rainfall locations, the inoculated plants compensated for reduced plant stand and harvestable tillers by producing heavier kernels. Disease severity, based on the subcrown internode lesion development during the soft dough growth stage, did not differ in the dryland and irrigated moisture regimes. However, disease severity was higher in the drought location than in the moderate and high rainfall locations. Prolonged drought and disease pressure during seedling development can result in grain yield reductions, whereas subsequent moisture will affect the crop's ability to compensate for common root rot. Key words: Hordeum vulgare, ranking and selection, canopy temperature

Sign in / Sign up

Export Citation Format

Share Document