Spotlight On...

Septoria on cereals.

A selection of abstracts is presented for Mycosphaerella graminicola (Septoria tritici) and wheat. This relates to a newly published book, edited by J. A. Lucas, P. Bowyer and H. M. Anderson. This book is based on papers presented at the 15th Long Ashton International Symposium, held in September 1997, and gives a wide-ranging view of the Septoria pathogens, the diseases they cause and strategies for their control.

We have also recently published the following books, the full content of which is available for a limited period under What's New:

Related items included in PEST CABWeb®:

Information is also available on:

TI: Response to selection in F(2) populations of two wheat crosses for resistance to Septoria tritici.
AU: Simon, M. R.\ Perello, A. E.\ Cordo, C. A.
JN: Cereal Research Communications
YR: 1998
VL: 26
NO: 3
PP: 275-280
LA: En
MS: 14 ref.
AA: Facultad de Ciencias Agrarias y Forestales, Universidad Nacional de La Plata. 60 y 118. CC 31. 1900 La Plata, Argentina.
AB: Septoria tritici blotch [Mycosphaerella graminicola] is an important disease of wheat in many areas of the world that causes significant yield losses. To efficiently breed wheat for resistance, an understanding of the inheritance of the resistance is required. Studies were conducted to determine the response to selection and realized heritability when selection for a reduction in percentage of pycnidial coverage was carried out in two wheat crosses (Don Ernesto Buck Naposta and Don Ernesto Marcos Juarez). Moderate values were obtained for response to selection and heritability. It is suggested that selection for resistance to the disease on a single plant basis could be successful, but would probably be slow. Optimization of selection is discussed.
DE:Mycosphaerella graminicola\wheat\Triticum aestivum\heritability\inheritance\yield losses\disease resistance\plant diseases\plant pathogens\plant pathogenic fungi\selection criteria\artificial selection
AN: 0P06901978\0M07802621

TI: Partial resistance and interaction in the Triticum aestivum-Septoria tritici association.
FT: Resistance partielle et interaction dans l'association Triticum aestivum-Septoria tritici.
AU: Bouami, F. el\ Jlibene, M.\ Mazouz, H.
JN: Al Awamia
YR: 1996, publ. 1998
NO: No. 95
PP: 29-38
LA: Fr
LS: en\ar
MS: 19 ref.
AA: Departement de Biologie, Faculte des sciences, Universite moulay Ismail, B.P. 4010 Meknes, 50000 Morocco.
AB: Sixteen bread wheat genotypes were tested at the seedling stage for their partial resistance to 27 isolates of S. tritici [Mycosphaerella graminicola] originating from diverse locations in Morocco. The parameters evaluated were incubation period (PI), latent period (PL), necrotic leaf area (SFN) and pycnidial coverage (RP). Significant genotype, isolate and genotypeisolate interaction effects were observed, indicating a differential host-pathogen interaction. Resistant genotypes (Nasma*2/14-2, Vee's'/Snb's', Saada and Tegyey) had longer PI and PL, and reduced SFN and RP. The most susceptible genotype, Nasma, had short PI and PL, and large SFN fully covered with pycnidia. An isolate from durum wheat was avirulent on the 16 bread wheat genotypes.
DE: plant diseases\plant pathogens\plant pathogenic fungi\Mycosphaerella graminicola\interactions\wheat\Triticum durum\genotypes\isolates\Triticum aestivum\disease resistance\genetics\host parasite relationships
GL: Morocco

TI: Inheritance of partial resistance to Septoria tritici in wheat, Triticum aestivum L.
FT: Heredite de la resistance partielle a Septoria tritici chez le ble, Triticum aestivum L.
AU: Bouami, F. el\ Jlibene, M.
JN: Al Awamia
YR: 1996, publ. 1998
NO: No. 95
PP: 21-28
LA: Fr
LS: en\ar
MS: 17 ref.
AA: Departement de biologie, Faculte des sciences, Universite Moulay Ismail, B.P. 4010, Meknes, 50000, Morocco.
AB: Inheritance of 4 resistance components to Septoria tritici [Mycosphaerella graminicola]: incubation period (IP), latent period (LP), leaf necrosis (LN) and pycnidial density (PD), was studied. Testing of Parent-1, Parent-2, F, Backcross-1, Backcross-2 and 2 generations of 4 crosses between bread wheat genotypes at the seedling stage against 2 isolates of M. graminicola indicated simple Mendelian inheritance of all the components. Long incubation period seemed to be controlled by 2 complementary genes, long latent period was controlled by a single dominant gene and low pycnidial density was also controlled by a single dominant gene. Low necrotic leaf area was controlled by one dominant gene either alone or coupled with another dominant or recessive gene, depending on the genotype. Studies of phenotypic correlations between components of resistance suggested that LP, LN and PD may be pleiotropic effects of the same gene, whilst PI seemed to be independent of the other components.
DE: plant diseases\plant pathogens\plant pathogenic fungi\Mycosphaerella graminicola\Triticum\Triticum aestivum\wheat\disease resistance\genetics\genes\genotypes\inheritance\isolates\backcrosses

TI: Leaf spot diseases of wheat and triticale in Southern Ukraine.
AU: Gontarenko, O. V.\ Babayants, L. T.\ Gerzhova, M. A.
JN: Mikologiya i Fitopatologiya
YR: 1998
VL: 32
NO: 2
PP: 61-64
LA: Ru
LS: en
MS: 14 ref.
AB: In these investigations in the Ukraine, Septoria tritici [Mycosphaerella graminicola] was the major pathogen of winter bread wheat. Winter durum wheat and triticale were mostly infected by Scolicotrichum graminis. Drechslera tritici-repentis, Ascochyta graminicola, Rhynchosporium graminum and Fusarium spp. were also identified as pathogens of wheat and triticale.
DE: Triticale\Ukraine\wheat\Triticum aestivum\plant diseases\plant pathogens\plant pathogenic fungi\Scolicotrichum graminis\Drechslera tritici-repentis\Ascochyta graminicola\Rhynchosporium graminum\Fusarium\Mycosphaerella graminicola
GL: Ukraine

TI: Changes of virulence in populations of Mycosphaerella graminicola Fuck Schroether on wheat.
FT: Cambio de virulencia en poblaciones de Mycosphaerella graminicola Fuck Schroether sobre trigo.
AU: Cordo, C. A.\ Perello, A. E.\ Arriaga, H. O.
JN: Investigacion Agraria, Produccion y Proteccion Vegetales
YR: 1998
VL: 13
NO: 1/2
PP: 77-86
LA: Es
LS: en
MS: 20 ref.
AA: Facultad de Ciencias Agrarias y Forestales, UNLP, CIC y CONICET. Calle 60 y 119 (1900), La Plata, Pcia. de Buenos Aires, Argentina.
AB: Virulence variations in two populations (P and P) of M. graminicola were studied by inoculation of sub-isolates of several generations on differential wheat cultivars carrying Bobwhite "S" germplasm. Population P and P were isolated from wheat lines LAJ 3139 and LPI/Bbw "S", respectively, and the sub-isolates within each population obtained by isolation and single-spore culture from plants of the correspondent line. Plants of the differential cultivars were inoculated in the greenhouse and the amount of disease incidence was estimated as the percentage of leaf surface covered by pycnidia 24 days after inoculation. Generally, virulence increased in successive generations, this increase depending on sub-isolate and wheat cultivar. Isolates of the 2 populations also showed morphological variations between generations. The changes in virulence observed indicated vulnerability of the Bobwhite "S" germplasm carried by resistant wheat cultivars.
DE: Mycosphaerella graminicola\virulence\cultivars\germplasm\inoculation\morphology\wheat\Triticum aestivum\plant pathogens\plant pathogenic fungi
AN: 0M07802638

TI: Transformation of the phytopathogen Mycosphaerella graminicola to carbendazim and hygromycin B resistance.
AU: Payne, A. C.\ Grosjean-Cournoyer, M. C.\ Hollomon, D. W.
JN: Current Genetics
YR: 1998
VL: 34
NO: 2
PP: 100-104
LA: En
MS: 23 ref.
AA: IACR-Long Ashton Research Station, Department of Agricultural Sciences, University of Bristol, Long Ashton, Bristol, BS419AF, UK.
AB: The fungal wheat pathogen M. graminicola was transformed to carbendazim tolerance and hygromycin B resistance. A -tubulin gene from a M. graminicola strain tolerant of carbendazim was cloned and used to transform a sensitive strain to carbendazim tolerance. Hygromycin B-resistant transformants (up to 8/g of transforming DNA) arose at a higher rate than -tubulin transformants (up to 0.6/g of DNA). Transformants were able to infect wheat, and were morphologically similar to recipient strains.
DE: carbendazim\Mycosphaerella graminicola\DNA\wheat\Triticum aestivum\plant pathogens\plant pathogenic fungi\fungicides\fungicide tolerance\genetic transformation\transgenics\fungal genetics\hygromycin B\antibiotics\antibiotic resistance
AN: 0M07802460

TI: Immunodiagnosis as an aid to the timing of fungicide sprays for the control of Mycosphaerella graminicola on winter wheat in the UK.
CT: Brighton Crop Protection Conference: Pests & Diseases - 1998: Volume 2: Proceedings of an International Conference, Brighton, UK, 16-19 November 1998.
AU: Kendall, S. J.\ Hollomon, D. W.\ Selley, A.
YR: 1998
PP: 701-706
BN: ISBN 0-901396-51-7
LA: En
MS: 7 ref.
AA: IACR-Long Ashton Research Station, Department of Agricultural Sciences, University of Bristol, Long Ashton, Bristol BS41 9AF, UK.
AB: Over 85% of the grain-filling capacity of wheat is attributed to the top 2 leaves. Therefore, if full yield potential of the crop is to be realised, these leaves must be protected from disease. Stagonospora nodorum and Mycosphaerella graminicola are often present as a disease complex early in the growing season, but M. graminicola is more prevalent during grain-filling. Immunodiagnosis, allowing pre-symptomatic detection of septoria diseases, was used as an aid for improving the timing of fungicide sprays in the UK. Over 5 years, field trials established that pre-symptomatic detection of M. graminicola on leaf 3 can be an accurate indicator of the optimum timing of a second fungicide spray for the protection of the top 2 leaves for the duration of grain-filling, and that this timing is related to cultivar susceptibility.
DE: conferences\chemical control\plant disease control\Mycosphaerella graminicola\wheat\Triticum aestivum\Stagonospora nodorum\plant diseases\plant pathogens\plant pathogenic fungi\immunodiagnosis\fungicides
AN: 0M07802603

TI: Isolation and characterization of microsatellite loci in the wheat pathogen Mycosphaerella graminicola.
AU: Owen, P. G.\ Ming Pei,\ Karp, A.\ Royle, D. J.\ Edwards, K. J.
JN: Molecular Ecology
YR: 1998
VL: 7
NO: 11
PP: 1611-1612
LA: En
MS: 5 ref.
AA: IACR-Long Ashton Research Station, Department of Agricultural Sciences, University of Bristol, Long Ashton, Bristol BS419AF, UK.
AB: A microsatellite enriched library was constructed from M. graminicola using the microsatellite motifs CA, CT, CG, CAA and CGG. Nine primer sets were suitable for screening purposes. Allelic variability of the microsatellites was determined using genomic DNA isolated from 12 individual isolates produced on senescent leaves of winter wheat cv. Longbow, collected from an unsprayed field plot (128 m) at Long Aston Research Station, UK, in June 1995. The number of alleles ranged from 2 to 4, with a genetic diversity value of 0.278-0.736. For 3 primer sets, the size range of the alleles observed would allow for several more alleles to exist in the Septoria population. Using the primers, all 12 isolates were distinguished as individual genotypes.
DE: polymerase chain reaction\Mycosphaerella graminicola\characterization\loci\wheat\pathogens\Triticum aestivum\molecular genetics\plant pathogens\plant pathogenic fungi\genetic diversity\population genetics\microsatellites\plant diseases\plant pathogens\plant pathogenic fungi\genetic analysis
AN: 0M07802635

TI: A 1-3 glucan, specific to a marine alga, stimulates plant defence reactions and induces broad range resistance against pathogens.
CT: Brighton Crop Protection Conference: Pests & Diseases - 1998: Volume 2: Proceedings of an International Conference, Brighton, UK, 16-19 November 1998.
AU: Joubert, J. M.\ Yvin, J. C.\ Barchietto, T.\ Seng, J. M.\ Plesse, B.\ Klarzynski, O.\ Kopp, M.\ Fritig, B.\ Kloareg, B.
YR: 1998
PP: 441-448
BN: ISBN 0-901396-51-7
LA: En
MS: 13 ref.
AA: Laboratoires GOEMAR, Avenue du General Patton, 35400 Saint Malo, France.
AB: Laboratoires Goemar have identified, isolated and industrially extracted from a brown alga a natural molecule, a 1-3 glucan (code GL32) which stimulates plant defence reactions and induces resistance to diseases. GL32 consists of several units of D-glucopyranosides linked by 1-3 bonds and branches linked by 1-6 bonds. Studies showed that GL32 is harmless to man and the environment. Treatment of tobacco, tomato and wheat cell cultures, and wheat seedlings with GL32 induced metabolic changes typical of defence responses: early events (ionic fluxes, phosphorylations, oxidative burst), stimulation of the phenylpropanoid and lipid-derived pathways (leading to the signals salicylic acid and jasmonates, respectively), and production of PR-proteins (known for their high antimicrobial potential). While GL32 had no direct antifungal activity, spraying with GL32 at low concentrations (20-50 g/ha) efficiently protected wheat seedlings against infection by Septoria tritici [Mycosphaerella graminicola] and Erysiphe graminis. Furthermore, when combined with synthetic fungicides, GL32 increased their efficiency at low concentrations.
DE: conferences\algae\cell cultures\fungicides\induced resistance\disease resistance\salicylic acid\Mycosphaerella graminicola\Erysiphe graminis\plant pathogens\plant pathogenic fungi\plant pathogens\defence mechanisms\-1,3 glucan\disease resistance\tobacco\Nicotiana tabacum\tomato\Lycopersicon esculentum\wheat\Triticum aestivum\fungicides\pathogenesis-related proteins
AN: 0M07802601

TI: Factors affecting strength of selection for resistance to DMI fungicides in Septoria tritici.
CT: Brighton Crop Protection Conference: Pests & Diseases - 1998: Volume 2: Proceedings of an International Conference, Brighton, UK, 16-19 November 1998.
AU: Metcalfe, R. J.\ Shaw, M. W.\ Russell, P. E.
JN: Brighton Crop Protection Conference: Pests & Diseases - 1998: Volume 2: Proceedings of an International Conference, Brighton, UK, 16-19 November 1998
YR: 1998
PP: 535-540
LA: En
MS: 8 ref.
AA: Department of Agricultural Botany, University of Reading, 2 Earley Gate, RG62AU, UK.
AB: The effects of dose and fungicide systemicity on selection for fungicide tolerance in S. tritici [Mycosphaerella graminicola] were examined for prochloraz, flutriafol and fluquinconazole. In an inoculated field experiment in the UK, using 1/8 or 1/4 field doses, sprays of all fungicides caused significant tolerance selection. The strength of selection varied with fungicide, position of infection in the canopy and along individual wheat leaves. Increasing the dose from 1/8 to 1/4, and applying split 1/8 doses, significantly increased selection. In glasshouse experiments, fungicide applications caused unexpected stimulation of infection and selection for susceptibility. Tracing of radio-labelled fluquinconazole showed that translocation was modified by infection.
DE: fungicides\Mycosphaerella graminicola\flutriafol\prochloraz\fluquinconazole\susceptibility\che mical control\fungicide tolerance\wheat\plant diseases\plant pathogens\plant pathogenic fungi\Triticum aestivum\conferences
AN: 0M07802403

TI: The management of Stagonospora nodorum on winter wheat in south west England.
CT: Brighton Crop Protection Conference: Pests & Diseases - 1998: Volume 3: Proceedings of an International Conference, Brighton, UK, 16-19 November 1998.
AU: Lockley, K. D.\ Clark, A. N. S.\ Hodgson, I.
YR: 1998
PP: 999-1004
BN: ISBN 0-901396-52-5
LA: En
MS: 3 ref.
AA: ADAS, Mamhead Castle, Mamhead, Exeter, EX68HD, UK.
AB: Two experiments were conducted on winter wheat in Cornwall, UK, in 1997. In Experiment 1, the activities of fungicides applied as single sprays at growth stage (GS) 39 against Stagonospora nodorum [Leptosphaeria nodorum] were investigated on cultivar Brigadier. Triazole fungicides, particularly metconazole, tebuconazole and epoxiconazole gave good disease control on leaf 2. Flusilazole was more effective at full dose than at reduced doses. Strobilurin fungicides gave variable disease control. Azoxystrobin demonstrated moderate eradicant activity but kresoxim-methyl + fenpropimorph was less effective, similar to the protectant fungicide chlorothalonil. The anilinopyrimidine fungicide cyprodinil showed good activity against L. nodorum, but its lack of activity against Septoria tritici [Mycosphaerella graminicola] compromised disease control. Yield was severely reduced by L. nodorum, and untreated plots yielded 2.17 t/ha. Full dose kresoxim-methyl + epoxiconazole and epoxiconazole alone increased yield to 4.78 and 5.21 t/ha, respectively. Experiment 2 examined the interaction of host resistance and fungicide dose. By GS 75, most cultivars required a minimum of three-quarter dose to give adequate control of a disease complex of L. nodorum and M. graminicola on the flag leaf. Glume blotch was more severe on cv. Admiral, and was little affected by fungicides. The combination of severe L. nodorum on upper leaves and ears caused considerable yield losses. Admiral yielded only 0.54 t/ha without fungicide treatment and 1.38 t/ha with a full dose of tebuconazole. The yield of Brigadier was also severely reduced and was lower than that of more resistant cultivars. The most resistant cultivar, Spark, yielded 3.07 t/ha without fungicide and 5.35 t/ha with a full dose of tebuconazole.
DE: conferences\Leptosphaeria nodorum\fungicides\metconazole\tebuconazole\epoxiconazole\flusilazol e\strobilurins\azoxystrobin\kresoxim-methyl\fenpropimorph\chlorothal onil\cyprodinil\Mycosphaerella graminicola\yield losses\cultivars\disease resistance\chemical control\plant disease control\plant diseases\plant pathogens\plant pathogenic fungi\wheat\Triticum aestivum
AN: 0M07802618

TI: Simulation modelling for crop-disease spraying management.
AU: Dahab, M. H.\ O'Callaghan, J. R.
JN: AMA, Agricultural Mechanization in Asia, Africa and Latin America
YR: 1998
VL: 29
NO: 3
PP: 27-32
LA: En
MS: 13 ref.
AA: Dept. of Agric. Engineering, Faculty of Agriculture, University of Khartoum, Shambat-P.O. Box 32, Sudan.
AB: Two simulation models were developed: one for wheat crop growth and the other, to simulate the exponential growth of Septoria tritici [Mycosphaerella graminicola] disease on the uppermost 4 leaves of wheat. The coupled crop-disease model was used to predict crop losses and to compare and analyse the cost/benefit of different spray strategies for controlling disease. The 3 control methods: insurance treatment, routine spraying and managed disease control were not economically viable under the assumptions used and gave average extra costs of 44%, 17% and 8.9%, respectively, when compared with the value of the untreated simulated crop yield loss.
DE: simulation models\spraying\management\economic analysis\wheat\Triticum aestivum\wheat\Mycosphaerella graminicola\plant disease control\plant diseases\fungicides\plant pathogenic fungi\application methods
GL: Sudan
AN: 8A02303314\0M07800326\6T01600373

TI:Remarks on the occurrence of septoria leaf blotch (Mycosphaerella graminicola) on winter wheat in Poland.
FT: Uwagi o wystepowaniu septoriozy paskowanej lisci (Mycosphaerella graminicola) na pszenicy ozimej w Polsce.
AU: Zamorski, C.\ Nowicki, B.
JN: Biuletyn Instytutu Hodowli i Aklimatyzacji Roslin
YR: 1997, publ. 1998
NO: No. 204
PP: 267-275
LA: Pl LS: en
MS: 27 ref.
AA: Katedra Fitopatologii, Szkoa Gowna Gospodarstwa Rolniczego, Warszawa, Poland.
AB: Observations conducted during 1994-96 in Poland indicated that M. graminicola occurred on winter wheat every year and that the degree of infection was higher in some regions than in others. Highest infection was noted in 1995 and the lowest in 1994. The degree of infection for the majority of cultivars and breeding lines was quite high. Some cultivars were characterized by very high infection, but some old cultivars showed no trace of infection despite favourable weather conditions and the presence of diseased plants in neighbouring fields. Field observation of cultivars and breeding lines showed different reactions to M. graminicola infection.
DE: Mycosphaerella graminicola\Triticum aestivum\cultivars\wheat\plant diseases\disease resistance\plant pathogenic fungi\disease surveys\plant pathogens
GL: Poland
AN: 0P06811644\6T01504509\0M07800329

TI: Variety: 'Nyabing' syn WAWHT1389. Application
NO: 97/123.
CA:Australia, Agriculture Western Australia\Grain Research and Development Corporation
JN: Plant Varieties Journal
YR: 1998
VL: 11
NO: 1
PP: 53-54
LA: En
AA: Agriculture Western Australia, Perth, Western Australia, Australia.
AB: This ASW grade (suitable for blending with noodle wheats) spring wheat variety, with erect habit, medium-short height and medium maturity, was derived from crosses involving WT329, IW753 and WD194 via selection for adaptation to high, medium and early planting in low rainfall zones of the southern agricultural areas of Western Australia. Nyabing was evaluated together with Spear, Halberd and Aroona in trials conducted at Northam, Western Australia during 1997-98. Submitted for the registration of plant variety rights in Australia, Nyabing possesses resistance to Septoria nodorum [Leptosphaeria nodorum], S. tritici [Mycosphaerella graminicola] and stem and leaf rust [Puccinia graminis and P. recondita].
DE: wheat\Triticum aestivum\cultivars\Nyabing\WAWHT1389\varieties\characteristics\Lepto sphaeria nodorum\Mycosphaerella graminicola\Puccinia graminis\Puccinia recondita\plant diseases\disease resistance\plant pathogenic fungi\disease resistance
GL: Australia\Western Australia
AN: 6T01503458\0P06811539\0Q05108826

TI: Variety: 'Calingiri' syn WAWHT2024. Application
NO: 97/125.
CA: Australia, Agriculture Western Australia\Grain Research and Development Corporation
JN: Plant Varieties Journal
YR: 1998
VL: 11
NO: 1
PP: 50-51
LA: En
AA: Perth, WA, Australia.
AB: Submitted for the registration of plant variety rights in Australia, this ASW noodle grade spring wheat (Triticum aestivum) variety was derived from the cross Chino/Kulin via selection for adaptation to high, medium and early sowing in low rainfall zones of the southern agricultural areas of Western Australia. Calingiri was evaluated together with Eradu, Gamenya and Kulin in trials conducted at Northam, Western Australia during 1997-98. Calingiri is an erect, medium height, late maturing variety which is resistant to stripe rust [Puccinia striiformis] and possesses useful resistance to Septoria tritici [Mycosphaerella graminicola] and leaf rust [P. recondita].
DE: wheat\Triticum aestivum\cultivars\Calingiri\WAWHT2024\varieties\disease resistance\Puccinia recondita\Puccinia striiformis\Mycosphaerella graminicola\plant pathogens\plant diseases\plant pathogenic fungi\characteristics
GL: Australia\Western Australia
AN: 6T01503457\0P06810264\0Q05108823

TI: Registration of 'TAM 301' wheat.
AU: Marshall, D. S.\ Sutton, R. L.\ Worrall, W. D.\ Rooney, L. W.\ Lazar, M. D.\ McDaniel, M. E.\ Nelson, L. R.
JN: Crop Science
YR: 1998
VL: 38
NO: 2
PP: 552-553
LA: En
AA: Texas A&M University, REC, 17360 Coit Rd., Dallas, TX 75252, USA.
AB: Released in 1995 and derived from the cross Mit/Kavkaz, TAM301 (PI596544) is an awned, semidwarf, hard red winter wheat adapted to all wheat-growing areas of Texas, where it consistently outyielded the control cultivars and performed best at locations in north and central Texas. From 1992 to 1995, TAM301 had the highest average grain yield (3870 kg/ha) compared with 18 control cultivars. TAM301 carries the leaf rust (Puccinia recondita) resistance genes Lr1, Lr2a, Lr10 and Lr26, together with an additional gene, either Lr3 or Lr24. It is also more resistant than most commercially grown hard red winter wheats to Septoria tritici [Mycosphaerella graminicola], its resistance being similar to that of Kavkaz, is highly resistant to Erysiphe graminis f.sp. tritici and moderately resistant to barley yellow dwarf luteovirus and Stagonospora nodorum [Leptosphaeria nodorum].
DE: registration\wheat\Triticum aestivum\cultivars\TAM301\yields\variety trials\Puccinia recondita\Mycosphaerella graminicola\Erysiphe graminis\Erysiphe graminis f.sp. tritici\barley yellow dwarf luteovirus\Leptosphaeria nodorum\disease resistance\plant diseases\plant pathogens\plant pathogenic fungi\genes\genetics
GL: USA\Texas
AN: 6T01503516\0P06810253\0Q05108817

TI: Diallel analysis of four resistance components to Septoria tritici in six crosses of wheat (Triticum aestivum).
AU: Simon, M. R.\ Cordo, C. A.
JN: Plant Breeding
YR: 1998
VL: 117
NO: 2
PP: 123-126
LA: En
MS: 16 ref.
AA: Departamento de Produccion Vegetal, Cerealicultura, Facultad de Ciencias Agrarias y Forestales, Universidad Nacional de La Plata, 60 y 118, CC31, 1900 La Plata, Argentina.
AB: Four resistance components, i.e. incubation period, latent period, maturation period and pycnidial coverage, were studied in a diallel cross of four wheat cultivars differing in susceptibility to Septoria tritici [Mycosphaerella graminicola]. Inoculations and evaluations were carried out at the fourth leaf stage for two years. A combined ANOVA for both years exhibited a significant interaction between crosses and years for maturation period. A separate ANOVA for each year was done for this trait. The combined ANOVA showed that crosses were significantly different for incubation, latent period and pycnidial coverage. Cross effects were also significant for maturation period in each year for the separate ANOVA. Year effects were significant for latent period and maturation period. General combining ability (GCA) was significant and preponderant for incubation period, latent period and pycnidial coverage. For maturation period, the separated ANOVA showed the significance of the GCA for both years. Specific combining ability (SCA) was significant for incubation and pycnidial coverage and for maturation in one year. The preponderance of the additive genetic variance for all traits indicates the possibility of selecting for them in order to obtain improved cultivars. Incubation period was inherited independently of maturation period and pycnidial coverage, indicating that combinations of some of those characters may lead to more effective and durable resistance.
DE: Triticum aestivum\inheritance\Mycosphaerella graminicola\diallel analysis\crosses\wheat\plant pathogens\plant diseases\plant pathogenic fungi\varietal reactions\disease resistance\analysis of variance\general combining ability\specific combining ability\genetic variance\combining ability
AN: 0P06809070\0M07708155\6T01503807

TI: Quality response of twelve hard red winter wheat cultivars to foliar disease across four locations in central Kansas.
AU: Vamshidhar Puppala\ Herrman, T. J.\ Bockus, W. W.\ Loughin, T. M.
JN: Cereal Chemistry
YR: 1998
VL: 75
NO: 1
PP: 94-99
LA: En
MS: 19 ref.
AA: Department of Grain Science and Industry, Kansas State University, Manhattan, KS 66506-2201, USA.
AB: Twelve hard red winter wheat cultivars were grown at four locations in central Kansas, USA, to evaluate the role of foliar fungal diseases on wheat end-use quality in 1995. Disease was allowed to develop naturally on control plots and was controlled partially on plots treated with a systemic fungicide. After harvest, wheat samples were evaluated for the impact of the disease complex (leaf rust (Puccinia recondita), tan spot (Pyrenophora tritici-repentis), speckled leaf blotch (Mycosphaerella graminicola)) on physical grain quality, grain protein, milling properties, flour absorption, and peak mixing time. Data were analysed using a mixed model to account for random (location and block) and fixed (cultivar and fungicide) effects. Location significantly influenced quality characteristics except kernel size and peak mixing time. The magnitudes of variation among random effects on all quality characteristics were larger for location than for the interactions between location cultivar and location fungicide. The fixed effects portion of the analysis revealed that the cultivar fungicide treatment interaction significantly affected test weight, kernel protein, and flour absorption. Fungicide treatment resulted in significant increases in yield and kernel weight. Cultivar significantly affected all quality characteristics except kernel size and peak mixing time. Disease resistance exerted a significant influence on yield and test weight. The economic benefit associated with improved wheat quality from fungicide treatment was variety specific. Three cultivars (TAM 107, Karl 92, and Ike), which account for 50% of the area planted to wheat in Kansas in 1997, demonstrated positive improvements in test weight and protein in response to fungicide treatment.
DE: Triticum aestivum\winter wheat\quality\cultivars\Puccinia recondita\Pyrenophora tritici-repentis\Mycosphaerella graminicola\quality\protein content\milling quality\wheat flour\fungicides\disease control\plant pathogens\plant diseases\plant pathogenic fungi\varietal reactions\disease resistance\seed size
GL: Kansas\USA
AN: 0P06803484\0M07703781\6T01502042

TI: Biocontrol of Botrytis cinerea on grapevine and Septoria spp. on wheat.
CT: Proceedings, 50th international symposium on crop protection, Gent, 5 May 1998. Part IV.
AU: Lennartz, B.\ Schoene, P.\ Oerke, E. C.
JN: Mededelingen - Faculteit Landbouwkundige en Toegepaste Biologische Wetenschappen, Universiteit Gent
YR: 1998
VL: 63
NO: 3b
PP: 963-970
LA: En
MS: 14 ref.
AA: Institute for Plant Diseases, University of Bonn Nussallee 9, 53115 Bonn, Germany.
AB: The antagonistic fungi Ulocladium atrum and Chaetomium cochlioides were able to colonise necrotic tissue faster than fungal leaf pathogens. Both antagonists were able to reduce the epidemic spread of B. cinerea on grapevine as well as of S. nodorum [Leptosphaeria nodorum] and S. tritici [Mycosphaerella graminicola] on wheat under field conditions in Germany. The limited epidemic spread of the pathogens resulted in a lower disease level in grapevine and wheat and in a higher yield compared with untreated plants in wheat. Results of research activities in 1997 are given and the integration of biological control into practical crop production and crop protection systems are discussed.
DE: grapes\wheat\Triticum aestivum\antagonists\biological control\Ulocladium atrum\Chaetomium cochliodes\Botrytis cinerea\Leptosphaeria nodorum\Mycosphaerella graminicola\biological control agents\plant disease control\plant diseases\plant pathogens\plant pathogenic fungi
GL: Germany
AN: 0M07802150

TI: Effect of adjuvants on the activity of fungicides in winter wheat under field conditions.
CT: Proceedings, 50th international symposium on crop protection, Gent, 5 May 1998. Part IV.
AU: Derycke, V.\ Haesaert, G.\ Reekmans, S.\ Auda, M.\ Latre, J.\ Hartmann, F.
JN: Mededelingen - Faculteit Landbouwkundige en Toegepaste Biologische Wetenschappen, Universiteit Gent
YR: 1998
VL: 63
NO: 3b
PP: 1041-1045
LA: En
MS: 5 ref.
AA: Hogeschool Gent, Department of Biotechnology, Landscape Architecture and Agriculture Voskenslaan 270, B-9000 Gent, Belgium.
AB: During 3 subsequent growing seasons in 1994-97, field experiments were carried out to study the effect of adjuvants on the activity of fungicides (epoxiconazole, tebuconazole and kresoxim-methyl) in winter wheat against Septoria tritici [Mycosphaerella graminicola] and Erysiphe graminis. The experiments were set up on a clay soil with the winter wheat variety Forby, according to a completely randomised block design with 4 replicates, at an experimental farm in Diksmuide, Belgium. Several fungicide-adjuvant combinations were studied. Fungicide was applied at normal application rate (NAR) or at reduced rate (75% NAR) and combined with 0.1 % adjuvant. It was suggested that adjuvants based on carbohydrate chemistries (such as alkyl polysaccharides and olefine diglucamides) enhanced the activity of many of the tested fungicides.
DE: adjuvants\fungicides\wheat\Triticum aestivum\Erysiphe graminis\Mycosphaerella graminicola\surfactants\plant disease control\chemical control\plant diseases\plant pathogens\plant pathogenic fungi\epoxiconazole\tebuconazole\kresoxim-methyl
GL: Belgium
AN: 0M07801907

TI: Efficiency of seed treaters on winter wheat.
FT: Beicu efektyvumas zieminiams kvieciams.
AU: Dabkevicius, Z.\ Semaskiene, R.\ Gaurilcikiene, I.
JN: Zemdirbyste, Mokslo Darbai
YR: 1998
NO: No. 62
PP: 105-119
LA: Li
LS: ru\en
MS: 22 ref.
AA: Lietuvos zemdirbystes institutas, Akademija, Dotnuvos sen., Kedainiu rajonas, Lithuanian.
AB: During 1992-97, the efficiency of 9 seed treatments was investigated for disease control on winter wheat cultivars Alba (1992-95), Kosack (1994-96) and Zentos (1996-97) in Lithuania. Ethirimol + flutriafol + thiabendazole (as Ferrax), flutriafol (as Vincit), fenpiclonil (as Beret Universal) and Beret 05 FS had negative effects on seed emergence and germination in the laboratory, and on germination in the field for Kozac and Zentos. Seed treatments gave good control of Drechslera spp. Triadimenol (as Baytan Universal) and flutriafol were effective against Fusarium spp., and triadimenol, ethirimol + flutriafol + thiabendazole, flutriafol and fenpiclonil were effective against Alternaria spp. and mould. The treatments gave good control of seedborne root rot diseases of seedlings. Triadimenol, ethirimol + flutriafol + thiabendazole and flutriafol reduced sprouting. Seed treatments slightly increased the winter survival of wheat, and decreased spring mould and Septoria diseases at tillering. Later on, they had no effect on disease incidence and the severity of leaf and root rot diseases. Seed treatments were effective against bunt [Tilletia tritici]. The grain yield increase due to the treatments was low for Alba (0.14-0.40 t/ha). Fenpiclonil reduced grain yield to 0.36-0.41 t/ha. However, triadimenol, benomyl (as Benlate), ethirimol + flutriafol + thiabendazole, flutriafol and carboxin + thiram (as Vitavax 200 FF) increased the yield of Kozac and Zentos to 0.69-1.10 t/ha. In autumn, benomyl treatments had no effect.
DE: wheat\Triticum aestivum\Alternaria\plant disease control\Drechslera\seed germination\root rot\seedlings\Septoria\tillering\carboxin\yield increases\yields\fungicides\ethirimol\flutriafol\thiabendazole\fenpi clonil\triadimenol\benomyl\carboxin\thiram\chemical control\seed treatment\seeds\plant diseases\plant pathogens\plant pathogenic fungi
GL: Lithuania
AN: 0M07801906

TI: Intervention thresholds for Septoria tritici in wheat.
FT: Bekampfungsschwellen fur Septoria tritici bei Weizen.
AU: Forrer, H. R.\ Jenny, E.\ Hecker, A.
JN: Agrarforschung
YR: 1998
VL: 5
NO: 5
PP: 249-252
LA: De
LS: en\fr
MS: 3 ref.
AA: Eidgenossische Forschungsanstalt fur Agrarokologie und Landbau (FAL), Reckenholz, CH-8046 Zurich, Switzerland.
AB: Data were analysed from 10 field studies (1993-97) in Switzerland to investigate economic thresholds for the control of Septoria tritici [Mycosphaerella graminicola] in wheat. An economic threshold was established at 10% disease incidence on top leaves (growth stage 83-85), with intervention thresholds of 15% disease incidence on lower leaves (growth stages 41-45 and 57-59). Use of this threshold model would have resulted in more economically use of fungicides in 30 out of 33 cases.
DE: economic thresholds\models\Mycosphaerella graminicola\wheat\Triticum aestivum\plant diseases\plant pathogens\leaves\fungicides\plant disease control\chemical control\growth stages\data analysis
GL: Switzerland
AN: 0M07801924

TI: Isolation and heterologous expression of a gene encoding 4-hydroxyphenylpyruvate dioxygenase from the wheat leaf-spot pathogen, Mycosphaerella graminicola.
AU: Keon, J.\ Hargreaves, J.
JN: FEMS Microbiology Letters
YR: 1998
VL: 161
NO: 2
PP: 337-343
LA: En
MS: 17 ref.
AA: IACR-Long Ashton Research Station, Department of Agricultural Sciences, University of Bristol, Long Ashton, Bristol BS189AF, UK.
AB: The isolation and sequence of a gene encoding 4-hydroxyphenylpyruvate dioxygenase from M. graminicola, that directs the synthesis of 2, 5-dihydroxyphenylacetate (homogentisic acid, HGA), are described. The sequence of the deduced peptide showed homology to HPPDs from other organisms; the greatest identity was to a T-cell reactive protein, also identified as HPPD, from the human fungal pathogen Coccidioides immitis. As observed for HPPD from other sources, expression of the M. graminicola HPPD gene in Escherichia coli cells could be detected by the gradual development of a brown pigment in cultures as a result of the spontaneous oxidation and polymerisation of HGA. Pigment development in these cultures was prevented by the HPPD inhibitor sulcotrione.
DE: Mycosphaerella graminicola\wheat\Triticum aestivum\Escherichia\Escherichia coli\plant pathogens\plant pathogenic fungi\gene expression\genes\nucleotide sequences\enzymes\molecular genetics
AN: 0M07800328

TI: Evaluation of azoxystrobin and a range of conventional fungicides on yield, Septoria tritici and senescence in winter wheat.
AU: Mercer, P. C.\ Ruddock, A.
JN: Tests of Agrochemicals and Cultivars
YR: 1998
NO: No. 19
PP: 24-25
LA: En
MS: 1 ref. Annals of Applied Biology 132, Supplement
AA: Applied Plant Science Division, Department of Agriculture for Northern Ireland, Newforge Lane, Belfast BT95PX, UK.
AB: In 1996, azoxystrobin, tebuconazole + triadimenol + chlorothalonil, epoxiconazole + fenpropimorph, flutriafol + chlorothalonil, and epoxiconazole + fenpropimorph + azoxystrobin were tested for their ability to control S. tritici [Mycosphaerella graminicola] infection of winter wheat in Northern Ireland, UK. All of the treatments controlled the disease with tebuconazole + triadimenol + chlorothalonil or combinations of epoxiconazole + fenpropimorph with axoxystrobin being the most effective.
DE: plant diseases\plant pathogens\plant pathogenic fungi\azoxystrobin\fungicides\senescence\Septoria\Mycosphaerella graminicola\wheat\Triticum aestivum\azoxystrobin\tebuconazole\triadimenol\chlorothalonil\epoxic onazole\fenpropimorph\flutriafol\Mycosphaerella graminicola\fungicides\chemical control\plant disease control
AN: 0M07800336\6T01600254

TI: Applied selection for resistances to Fusarium and Septoria diseases in wheat breeding programs.
CT: Proceedings, International symposium. New aspects of resistance research on cultivated plants, Aschersleben, Germany, 17-18 November, 1997.
AU: Walther, H.
JN: Beitrage zur Zuchtungsforschung - Bundesanstalt fur Zuchtungsforschung an Kulturpflanzen
YR: 1998
VL: 4
NO: 1
PP: 18-20
LA: En
MS: 1 ref.
AA: Federal Centre for Breeding Research on Cultivated Plants, Institute for Resistance Genetics, Graf Seinsheim-Str. 23, 85461 Grunbach, Germany.
AB: A multiple resistance selection model was developed for use in a wheat breeding programme with simultaneous improvements of resistance to head blight (F. culmorum), Septoria head and leaf blotch (S. nodorum [Leptosphaeria nodorum]) and speckled leaf blotch (S. tritici [Mycosphaerella graminicola]).
DE: Septoria\wheat\Triticum aestivum\Fusarium culmorum\Leptosphaeria nodorum\Mycosphaerella graminicola\disease resistance\plant diseases\plant pathogens\plant pathogenic fungi\models\breeding\conferences\artificial selection
AN: 0M07709954\6T01504505\0P06812757

TI: The occurrence of Septoria tritici and its teleomorph Mycosphaerella graminicola in the region of Upper Silesia in 1996.
AU: Gazek, M.\ Sikora, H.
JN: Journal of Plant Protection Research
YR: 1998
VL: 38
NO: 1
PP: 23-29
LA: En
LS: pl
MS: 9 ref.
AA: Plant Protection Institute, Poznan Sosnicowice Branch, ul. Gliwicka 29, 44-153 Sosnicowice, Poland.
AB: The occurrence of leaf blotch of wheat caused by S. tritici (teleomorph M. graminicola) was more frequent in 1996 in the Upper Silesia region, south-western Poland, than in previous years. Visual scoring and serological tests showed that the most rapid disease development occurred from the emergence of the flag leaf (GS 49) onwards. At the end of the dough ripe stage (GS 85) pseudothecia of M. graminicola were found on the necrotic leaf blotch spots although asci were not fully mature. After a period of storage, necrotic tissue with pseudothecia placed on water agar-streptomycin and subjected to low temperatures for 2-3 weeks, mature asci and germinating ascospores forming single conidia on ramifying mycelium were abundant.
DE: plant diseases\plant pathogens\plant pathogenic fungi\Mycosphaerella graminicola\Septoria\wheat\Triticum aestivum\incidence\aetiology\growth stages\asci\ascospores\conidia\emergence\flag leaf\temperature
GL: Poland
AN: 0M07709977\6T01504484

TI: Disease map and site specific fungicide application.
FT: Sygdomskort og positionsbestemt fungicidanvendelse.
CT: 15th Danish Plant Protection Conference. Pests and Diseases.
AU: Bjerre, K. D.\ Jrgensen, L. N.\ Secher, B. J. M.
JN: DJF Rapport, Markbrug
YR: 1998
NO: No. 3
PP: 131-144
LA: Da
LS: en
MS: 26 ref.
AA: Danmarks JordbrugsForskning, Afdeling For Plantebeskyttelse, Forskningscenter Flakkebjerg, DK-4200 Slagelse, Denmark.
AB: During 1997, 3 winter wheat (cv. Ritmo) fields at 3 different localities were monitored systematically for diseases in a 1212 m or 2424 m grid. In June the frequency of powdery mildew (Erysiphe graminis) on the 3 upper leaves was assessed and in July percentage disease on the 3 upper leaves was assessed for mildew and Septoria diseases (S. tritici [Mycosphaerella graminicola] and S. nodorum [Leptosphaeria nodorum]). Ratio vegetation index (RVI) was measured by spectral reflectance measurements and used as an index of crop density. Spectral reflectance measurements were done at the same points as disease assessment. Two fields had significant levels of mildew. The frequency of diseased plants in these fields varied from 0-75% and 0-55%. Mildew was found to dominate in areas close to shelterbelts, forest edges or other vegetation with lee effect. Lower levels were seen in wind exposed areas. The RVI in these fields varied from 5-28 and 5-34. No correlation could be found between RVI and mildew attacks. Septoria diseases were assessed in 2 fields in July. Attack varied from 2 to 44, respectively, from 12 to 32% coverage. RVI measured 15-16 days earlier varied considerably within the fields and a clear correlation between RVI and Septoria attack could be seen when mapping the results. Lowest attacks were seen in areas with the highest crop density. A trial from Roskilde experimental station in 1997 with 3 different seed rates (150, 300, 450 seeds/m) showed significantly higher levels of Septoria attack at the low seed rates, which confirmed the results of other Danish field trials. In the Roskilde trial, RVI at the end of May had the following ranking 450300150. Good possibilities for developing tillers at the lower seed rates changed the ranking to 300450150 from the middle of June. The crop density important for dispersal of Septoria by splash is going 1 or 2 latent periods back. This means that the varying levels of Septoria attack assessed late in June and in July can most likely be ascribed to crop density. If Septoria has first spread to the upper leaves the possibilities of having a good second disease cycle will be less influenced by dispersal from below. These preliminary results of disease assessment within fields suggest that general disease models can be made, in which a significant part of the variation in mildew attack caused by lee effects and in Septoria attack caused by varying crop density can be explained.
DE: plant diseases\plant pathogens\plant pathogenic fungi\Erysiphe graminis\Mycosphaerella graminicola\Leptosphaeria nodorum\wheat\Triticum aestivum\incidence\distribution\epidemiology\plant density\spacing\crop density\stand density\environmental factors\models\conferences\Danish Plant Protection Conference\Pests and Diseases
GL: Denmark
AN: 0M07709121\6T01504477

TI: Efficiency of fungicide and fungicide-fertilizer treatments applied in winter wheat conditions.
FT: Skutecnosc\acute zabiegow fungicydowych i fungicydowo-nawozowych stosowanych w uprawie pszenicy ozimej.
AU: Brzozowski, J.\ Brzozowska, I.\ Jastrzebska, M.
JN: Acta Academiae Agriculturae ac Technicae Olstenensis, Agricultura
YR: 1998
NO: No. 65
PP: 129-138
LA: Pl
LS: en
MS: 10 ref.
AA: Olsztyn University of Agriculture and Technology, Poland.
AB: The effect of Sportak [prochloraz] and Tilt [propiconazole] and mixtures with urea and multi-component fertilizer (Insol-3) on the health, crop structure, yield and crude protein content of winter wheat grain was studied. The fungicides reduced the intensity of Septoria glume blotch [Leptosphaeria nodorum], Septoria leaf blotch [Mycosphaerella graminicola] and powdery mildew (Erysiphe graminis) and increased the yield of winter wheat. Urea and Insol-3 used in a mixture with the fungicides improved the fungitoxic efficiency of the later in most cases. Foliar applications of Insol-3 also had a favourable effect on crop structure and yield. The treatments had no major influence on the crude protein content of winter wheat grain.
DE: plant diseases\plant pathogens\plant pathogenic fungi\plant disease control\chemical control\fungicides\wheat\Erysiphe graminis\Leptosphaeria nodorum\Mycosphaerella graminicola\prochloraz\propiconazole\fertilizers\urea
AN: 0M07709128\6T01504478

TI: Physiological, disease control and yield effects of kresoxim-methyl.
AU: Clark, B.\ Leandro, L.
JN: Agronomist
YR: 1998
NO: No. 2
PP: 15-17
LA: En
AA: ADAS Boxworth, Cambridgeshire, UK.
AB: Kresoxim-methyl, applied to wheat cultivars Pastiche and Brigadier infected with Septoria tritici [Mycosphaerella graminicola], helped to increase green leaf retention, produced higher chlorophyll concentration in leaves, increased light absorption by leaves, and in mixture with epoxiconazole gave yield responses above those achieved by the latter fungicide alone.
DE: kresoxim-methyl\wheat\Mycosphaerella graminicola\plant disease control\plant pathogens\plant diseases\plant pathogenic fungi\fungicides\control\chemical control
AN: 0M07708136\6T01503772

TI: Physiological effects of strobilurins and plant activators in relation to yield of winter wheat.
AU: Jones, D. R.\ Bryson, R. J.
JN: HGCA Project Report
YR: 1998
NO: No. 164
PP: 31 pp.
LA: En
MS: 4 ref.
AA: ADAS Rosemaund, Preston Wynne, Hereford HR1 3PG, UK.
AB: The results of a 1 year project, funded by the HGCA, into the physiological effects of strobilurins and plant activators on yield of winter wheat are reported. The strobilurin fungicides azoxystrobin and kresoxim-methyl (in formulation with epoxiconazole) were evaluated in comparison with the azole fungicide epoxiconazole. Septoria tritici [Mycosphaerella graminicola] was controlled well on winter wheat by epoxiconazole and epoxiconazole in formulation with kresoxim-methyl, but azoxystrobin was less effective. All the fungicides gave good control of yellow rust (Puccinia striiformis). The fungicide formulation gave small additional increases in green canopy duration, but disease control was no better. On the resistant cv. Pastiche, disease incidence was negligible, but fungicides delayed leaf senescence. Epoxiconazole + kresoxim-methyl resulted in increased chlorophyll content of the lower leaves compared with epoxiconazole and showed decreased light transmission through the leaves. Control of M. graminicola resulted in increased yields with the formulation of kresoxim-methyl and epoxiconazole resulting in significantly higher yields than the other treatments.
DE: plant diseases\plant pathogens\plant pathogenic fungi\wheat\plant disease control\chemical control\fungicides\Mycosphaerella graminicola\Puccinia striiformis\epoxiconazole\kresoxim-methyl\azoxystrobin\yields
AN: 0M07707365\6T01503788

TI: Canopy, disease and fungicide use.
CT: Management through understanding research into practice. Proceedings of the sixth HGCA R&D conference on cereals and oilseeds, Cambridge, UK, 8-9 January 1998.
AU: Paveley, N. D.\ Stevens, D. B.\ Hims, M.\ Ainsley, A. E.
YR: 1998
PP: 9.1-9.17
LA: En
MS: 14 ref.
AA: ADAS High Mowthorpe, Duggleby, Malton, North Yorkshire, YO17 8BP, UK.
AB: This paper provides a rationale for controlling input costs, whilst minimising risk, and summarises an approach to the evaluation of existing and novel fungicide activities for the control of Septoria tritici [Mycosphaerella graminicola] on wheat.
DE: plant diseases\plant pathogens\plant pathogenic fungi\plant disease control\chemical control\fungicides\wheat\fungi\Mycosphaerella graminicola
AN: 0M07707362\6T01503802

TI: Studies on dispersal of Septoria tritici pycnidiospores in wheat-clover intercrops.
AU: Bannon, F. J.\ Cooke, B. M.
JN: Plant Pathology
YR: 1998
VL: 47
NO: 1
PP: 49-56
LA: En
MS: 21 ref.
AA: Department of Environmental Resource Management, Faculty of Agriculture, University College Dublin, Belfield, Dublin 4, Irish Republic.
AB: Four experiments studied the effects of a clover understorey on pycnidiospore dispersal of S. tritici [Mycosphaerella graminicola] in a wheat-clover intercrop under simulated rain. Clover (cv. Alice) significantly reduced the dispersal of spores in a horizontal direction by 33% at a distance of 15 cm from a line inoculum source compared with a wheat (cv. Baldus) monocrop. The clover also reduced the vertical movement of spores from infected leaves at the base of wheat plants by an average of 63% compared to the monocrop, and this suggests that the main movement of spores was from the base upwards. Splash experiments using blue colour marker showed the vertical decline of splash and the number of drops per cm with height caught on paper adjacent to trays of clover was described by the exponential decline model. The effect of clover in reducing vertical splash approached an asymptote as the leaf area index of the understorey increased. Simulated rain-splash increased the level of disease on the flag leaf and, in 1 experiment, there was a significant interaction between rain-splash and clover in reducing the number of lesions on the flag leaf. The level of disease resulting from 1 splash event was low, indicating that subsequent pathogen multiplication is probably required to bring about high severities of disease.
DE: plant diseases\plant pathogens\plant pathogenic fungi\Mycosphaerella graminicola\wheat\Trifolium repens\spore dispersal\rain\artificial precipitation\rainfall simulators\intercropping\cropping systems\crop mixtures\mixed cropping\continuous cropping\lesions\incidence\epidemiology\spread\sporulation
AN: 0M07704752\6T01501974

TI: Appropriate fungicide doses for winter wheat and matching crop management to growth and yield potential.
AU: Paveley, N. D.\ Hims, M. J.\ Stevens, D. B.\ Clark, W. S.\ Bryson, R. J.
JN: HGCA Project Report
YR: 1998
NO: No. 166
PP: 188 pp.
LA: En
MS: ref. at ends of sections
AA: ADAS High Mowthorpe, Duggleby, Malton, N. Yorks YO17 8BP, UK.
AB: Two HGCA-funded projects are reported. The first project, "Appropriate fungicide doses for winter wheat", was conducted as 3 separate experiments on dose responses for conazole and morpholine fungicides, variety/dose interactions, and dose/timing combinations in multiple spray programmes. The experiments were concerned principally with Septoria tritici [Mycosphaerella graminicola]. The second project, "Matching crop management to growth and yield potential", looked at crop canopy development in relation to fungicide application, to examine the hypothesis that yield loss due to disease can be better explained using measurements of green leaf area and radiation interception than by assessment of disease severity alone. The experiments for this project were carried out within the main fungicide experiments described in the first part of the report. Crop growth and green leaf area index data are presented for different fungicide treatments. A technique for rapid non-destructive measurement of green leaf area index in the field is described.
DE: wheat\winter wheat\Triticum aestivum\fungal diseases\plant pathogenic fungi\fungicides\conazole fungicides\morpholine fungicides\Mycosphaerella graminicola\leaf area index\diseases\cultivars\varietal reactions\plant pathogens\plant diseases\chemical control\plant diseases control
AN: 0Q05108831\6T01504492\0M07800327