Effects of Pyrenophora teres on dry matter production and yield components of winter barley

Jordan, V. W. L.; Best, G. R.; Allen, E. C.

doi:10.1111/j.1365-3059.1985.tb01350.x

Cited by 16 publications

(8 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Pyrenophora teres Drechsler [anamorph: Drechslera teres (Sacc.) Shoemaker] is the causal agent of barley net blotch, a disease with a world-wide distribution that can cause substantial yield losses (Jordan et al 1985;Steffenson et al 1991). Several studies have documented high variability in the pathogenicity of the fungus (Harrabi and Kamel 1990;Tekauz 1990;Steffenson and Webster 1992).…”

Section: Introductionmentioning

confidence: 98%

Population genetic structure of Pyrenophora teresDrechs. the causal agent of net blotch in Sardinian landraces of barley (Hordeum vulgare L.)

et al. 2002

View full text Add to dashboard Cite

Monoconidial cultures of Pyrenophora teres, the causal agent of barley net blotch, were isolated from leaves collected from six populations of the barley landrace "S'orgiu sardu" growing in five agro-ecological areas of Sardinia, Italy, and genotyped using AFLPs. The 150 isolates were from lesions of either the "net form" (P. teres f. sp. teres) or the "spot form" (P. teres f. sp. maculata) of the disease. Of 121 AFLP markers, 42%, were polymorphic. Cluster analysis resolved the isolates into two strongly divergent groups (F(ST) = 0.79), corresponding to the net (45% of the isolates) and the spot (55% of the isolates) forms (designated the NFR and SFR groups, respectively). The absence of intermediate genotypes and the low number of shared markers between the two groups indicated that hybridization between the two formae is rare or absent under the field condition of Sardinia. Five of the barley populations hosted both forms but in different proportions. The SFR populations were similar in overall polymorphism to the NFR populations. However, compared to the SFR form, the NFR occurred in all fields sampled and showed a higher population divergence (F(ST) = 0.43 versus F(ST) = 0.09 with all isolates; F(ST) = 0.37 versus F(ST) = 0.06 with clone corrected samples) probably due to a lower migration rate. AFLP fingerprints resolved 117 distinct genotypes among the 150 isolates sampled (78%), 87% in SFR and 68% in NFR isolates. Although the absolute numbers may be a function of the number of AFLP markers assayed, the relative difference suggests that clonality is more prevalent among the NFR isolates (with 11 of 46 haplotypes observed more than once), compared with SFR isolates (7 of 71 haplotypes). Both digenic and multilocus linkage disequilibrium analyses suggested that sexual reproduction occurs at significant levels within the NFR and SFR populations, and that the relative contribution of sexual and asexual reproduction varies among different environments.

show abstract

Section: Introductionmentioning

confidence: 98%

Population genetic structure of Pyrenophora teresDrechs. the causal agent of net blotch in Sardinian landraces of barley (Hordeum vulgare L.)

et al. 2002

View full text Add to dashboard Cite

show abstract

“…Net blotch is a barley disease with a worldwide distribution that can cause substantial yield losses (Jordan et al 1985;Steffenson et al 1991). The causal agent is the fungus Pyrenophora teres Drechsler (anamorph: Drechslera teres (Sacc.)…”

Section: Introductionmentioning

confidence: 99%

Isolation and characterization of the mating-type locus of the barley pathogenPyrenophora teresand frequencies of mating-type idiomorphs within and among fungal populations collected from barley landraces

Rau¹,

Maier²,

Papa³

et al. 2005

Genome

View full text Add to dashboard Cite

Pyrenophora teres f. sp. teres mating-type genes (MAT-1: 1190 bp; MAT-2: 1055 bp) have been identified. Their predicted proteins, measuring 379 and 333 amino acids, respectively, are similar to those of other Pleosporales, such as Pleospora sp., Cochliobolus sp., Alternaria alternata, Leptosphaeria maculans, and Phaeosphaeria nodorum. The structure of the MAT locus is discussed in comparison with those of other fungi. A mating-type PCR assay has also been developed; with this assay we have analyzed 150 isolates that were collected from 6 Sardinian barley landrace populations. Of these, 68 were P. teres f. sp. teres (net form; NF) and 82 were P. teres f. sp. maculata (spot form; SF). Within each mating type, the NF and SF amplification products were of the same length and were highly similar in sequence. The 2 mating types were present in both the NF and the SF populations at the field level, indicating that they have all maintained the potential for sexual reproduction. Despite the 2 forms being sympatric in 5 fields, no intermediate isolates were detected with amplified fragment length polymorphism (AFLP) analysis. These results suggest that the 2 forms are genetically isolated under the field conditions. In all of the samples of P. teres, the ratio of the 2 mating types was consistently in accord with the 1:1 null hypothesis. This ratio is expected when segregation distortion and clonal selection among mating types are absent or asexual reproduction is rare. Overall, sexual reproduction appears to be the major process that equalizes the frequencies of the 2 mating types within populations.

show abstract

“…In still other cases there was full accordance between yield decrease and thousand grain weight reduction (Shipton, 1966;Smedegaard-Petersen, 1974). Jordan, Best & Allen (1985) studied the effect of the time of infection by inoculating one to several times during the growing season. Repeated inoculation had the strongest effect which could reduce the yield by up to 48%.…”

Section: J P Skou a N D V H A A H Rmentioning

confidence: 99%

Field screening for resistance to barley net blotch

Skou

Haahr

1987

Annals of Applied Biology

View full text Add to dashboard Cite

S U M M A R YInoculation with barley net blotch from infested straw debris was compared with that from diseased plants after sowing infected grains. The straw debris had a high, uniform inoculation potential which gave an early, continuing infection and easily reproducible results that were effective for screening barley cultivars in the field for resistance against a natural population of the pathogen. Further, it minimises an eventual influence from other leaf pathogens coming from the surroundings.Irrigation was decisive for the success of the methodespecially in the initial phase. Ten m separation with an immune crop was insufficient to completely prevent infection in the uninoculated plots.The tested 25 cvs were differentiated in six categories of resistant and susceptible on the basis of disease development and final level of attack. None of them was free of symptoms. The most resistant cvs kept a constant, low level of attack during the whole growing season, whereas the most susceptible cvs showed an early and rapidly increasing attack. Intermediate cvs were characterised with more or less slow increase of the attack. The size and proportion of the brown necrotic spots and the surrounding yellow halo varied greatly from one cultivar to the other.The grain yield reduction was due solely to an effect on the thousand grain weight which decreased linearly with the squared point score for net blotch. Further, the disease affected the quality of the grains as less nitrogen was transported from straw to grain in the severely diseased plants.

show abstract

Effects of Pyrenophora teres on dry matter production and yield components of winter barley

Cited by 16 publications

References 12 publications

Population genetic structure of Pyrenophora teresDrechs. the causal agent of net blotch in Sardinian landraces of barley (Hordeum vulgare L.)

Population genetic structure of Pyrenophora teresDrechs. the causal agent of net blotch in Sardinian landraces of barley (Hordeum vulgare L.)

Isolation and characterization of the mating-type locus of the barley pathogenPyrenophora teresand frequencies of mating-type idiomorphs within and among fungal populations collected from barley landraces

Field screening for resistance to barley net blotch

Contact Info

Product

Resources

About