Effects of crop rotations and fertilizer management on leaf spotting diseases of spring wheat in southwestern Saskatchewan

1998 ◽  
Vol 78 (3) ◽  
pp. 489-496 ◽  
Author(s):  
M. R. Fernandez ◽  
R. P. Zentner ◽  
B. G. McConkey ◽  
C. A. Campbell
Keyword(s):  
Spring Wheat ◽  
Leaf Spot ◽  
Leaf Tissue ◽  
Triticum Aestivum L ◽  
Fertilizer Application ◽  
Tan Spot ◽  
P Deficiency ◽  
Pyrenophora Tritici Repentis ◽  
Leaf Spots ◽  
Phaeosphaeria Nodorum

The objective of this study was to determine the effect of crop sequence, summerfallow frequency, and fertilizer application, on the severity of leaf spotting diseases of spring wheat (Triticum aestivum L.). In the field experiment examined, Pyrenophora tritici-repentis (Died.) Drechs. was the pathogen most commonly isolated from lesioned leaf tissue, followed by stagonospora blotch (Phaeosphaeria nodorum [E. Müller] Hedjaroude). The severity of leaf spots in wheat after fallow was greater than in monoculture continuous wheat, or in wheat after a noncereal crop. Percent area with leaf spots in wheat grown after wheat was higher than in wheat grown after flax (Linum usitatissimum L.) or lentil (Lens culinaris Medikus) in years with high disease pressure (1995 and 1996), but not in 1993 or 1994 when overall disease levels were low. Under soil N-deficient conditions, leaf spot levels increased in years with dry summers (1994 and 1996), whereas a P deficiency decreased leaf spot severity in years that had cool and wet springs (1995 and 1996). A survey of producers' fields confirmed the observations made in the research plots, in particular, wheat after wheat was not more severely diseased than wheat grown in rotation with a noncereal crop. We concluded that the use of fallow, or 1 yr of rotation with a noncereal crop, will not reduce leaf spotting diseases of spring wheat in southwestern Saskatchewan. The best rotation aimed at reducing the levels of disease appeared to be 2 consecutive years of spring wheat, followed by at least 2 yr of a noncereal crop, or by a noncereal crop and summerfallow. Key words: Leaf spot, tan spot, Pyrenophora tritici-repentis, stagonospora blotch, Phaeosphaeria nodorum, septoria blotch, Mycosphaerella graminicola, crop rotation, tillage, fertility

AC Foremost red spring wheat

1997 ◽  
Vol 77 (4) ◽  
pp. 657-660 ◽  
Author(s):  
J. B. Thomas ◽  
R. M. DePauw ◽  
R. E. Knox ◽  
E. Czarnecki ◽  
A. B. Campbell ◽  
...  
Keyword(s):  
Triticum Aestivum ◽  
Spring Wheat ◽  
Triticum Aestivum L ◽  
High Yield ◽  
Loose Smut ◽  
Common Bunt ◽  
Pyrenophora Tritici Repentis ◽  
Leaf Spots ◽  
Ustilago Tritici ◽  
Tilletia Laevis

AC Foremost, red-seeded spring wheat (Triticum aestivum L.), combines high grain yield with resistance to prevalent races of common bunt (caused by Tilletia laevis Kuhn in Rabenh. and T. caries (DC.) Tul. & C. Tul.), and loose smut except T9 (caused by Ustilago tritici (Pers.) Rostr. in a semidwarf, photoperiod insensitive background. AC Foremost has improved pre-harvest sprouting tolerance compared with Biggar, AC Taber, and Genesis; improved resistance to leaf rust (caused by Puccinia recondita Roberg ex Desmaz.) and leaf spots (caused by Septoria spp. and Pyrenophora tritici repentis (Died.) Drechs.) compared with Neepawa and Biggar, and earlier maturity compared with Biggar, AC Taber, and Genesis. AC Foremost is eligible for grades of the Canada Prairie Spring (Red) wheat class. Key words: Triticum aestivum L., cultivar description, loose smut resistance, common bunt resistance, high yield, red spring wheat

scholarly journals The emergence of cereal fungal diseases and the incidence of leaf spot diseases in Finland

2008 ◽  
Vol 20 (1) ◽  
pp. 62 ◽  
Author(s):  
M. JALLI ◽  
P. LAITINEN ◽  
S. LATVALA
Keyword(s):  
Spring Wheat ◽  
Leaf Spot ◽  
Fungal Pathogens ◽  
Plant Pathogens ◽  
Field Survey ◽  
Fungal Diseases ◽  
Cochliobolus Sativus ◽  
Pyrenophora Tritici Repentis ◽  
Fungal Plant Pathogens ◽  
First Time

Fungal plant pathogens causing cereal diseases in Finland have been studied by a literature survey, and a field survey of cereal leaf spot diseases conducted in 2009. Fifty-seven cereal fungal diseases have been identified in Finland. The first available references on different cereal fungal pathogens were published in 1868 and the most recent reports are on the emergence of Ramularia collo-cygni and Fusarium langsethiae in 2001. The incidence of cereal leaf spot diseases has increased during the last 40 years. Based on the field survey done in 2009 in Finland, Pyrenophora teres was present in 86%, Cochliobolus sativus in 90% and Rhynchosporium secalis in 52% of the investigated barley fields. Mycosphaerella graminicola was identified for the first time in Finnish spring wheat fields, being present in 6% of the studied fields. Stagonospora nodorum was present in 98% and Pyrenophora tritici-repentis in 94% of spring wheat fields. Oat fields had the fewest fungal diseases. Pyrenophora chaetomioides was present in 63% and Cochliobolus sativus in 25% of the oat fields studied.;

scholarly journals Characterizing Virulence of the Pyrenophora tritici-repentis Isolates Lacking Both ToxA and ToxB Genes

Pathogens ◽  
2018 ◽  
Vol 7 (3) ◽  
pp. 74 ◽  
Author(s):  
Jingwei Guo ◽  
Gongjun Shi ◽  
Zhaohui Liu
Keyword(s):  
Triticum Aestivum L ◽  
Tan Spot ◽  
Pyrenophora Tritici Repentis ◽  
Tan Spot Disease ◽  
Hard Red Winter Wheat ◽  
Winter Wheat Cultivars ◽  
Race 2 ◽  
Genomic Regions ◽  
Race 4 ◽  
Necrotrophic Effectors

The fungus Pyrenophora tritici-repentis (Ptr) causes tan spot of wheat crops, which is an important disease worldwide. Based on the production of the three known necrotrophic effectors (NEs), the fungal isolates are classified into eight races with race 4 producing no known NEs. From a laboratory cross between 86–124 (race 2 carrying the ToxA gene for the production of Ptr ToxA) and DW5 (race 5 carrying the ToxB gene for the production of Ptr ToxB), we have obtained some Ptr isolates lacking both the ToxA and ToxB genes, which, by definition, should be classified as race 4. In this work, we characterized virulence of two of these isolates called B16 and B17 by inoculating them onto various common wheat (Triticum aestivum L.) and durum (T. turgidum L.) genotypes. It was found that the two isolates still caused disease on some genotypes of both common and durum wheat. Disease evaluations were also conducted in recombinant inbred line populations derived from two hard red winter wheat cultivars: Harry and Wesley. QTL mapping in this population revealed that three genomic regions were significantly associated with disease, which are different from the three known NE sensitivity loci. This result further indicates the existence of other NE-host sensitivity gene interactions in the wheat tan spot disease system.

LEAF SPOT OF BANANAS CAUSED BY MYCOSPHAERELLA MUSICOLA: ASSOCIATED ASCOMYCETOUS FUNGI

1963 ◽  
Vol 41 (10) ◽  
pp. 1481-1485 ◽  
Author(s):  
R. H. Stover
Keyword(s):  
Leaf Spot ◽  
Leaf Tissue ◽  
Leaf Spots ◽  
Mycosphaerella Musicola ◽  
Banana Leaf

In addition to perithecia, spermagonia, and sporodochia of Mycosphaerella nmsicola Leach (Cercospora musac Zimm.), perithecia of M. minima Stahel, Leptosphaeria sp., Micronectridla sp. and Didymella sp. are present in banana leaf spots in Honduras. All of these fungi discharge ascospores from both surfaces of wet leaf spots. Discharges of M. musicola and Didymella are most abundant from June through December whereas ascospores of Micronectriella are abundant from January to June. Ascospores of M. minima and especially Leptosphaeria are abundant at all times. The two-celled ascospores of M. musicola, M. minima, and Didymella are readily identified by size, shape, and type of germination. M. musicola perithecia can be readily distinguished in non-sectioned lactophenol-cleared leaf tissue by the dark thick walls of the ostiole and periderm. M. minima and Micronectriella can produce ascospores in siugle-ascospore cultures. The latter also produces Fusarium macroconidia. Micronectriella sp. is present in young healthy leaves and is considered a banana leaf inhabitant. Perithecia of all species are more abundant in areas of mass leaf spot infection than in single, scattered spots.

A gene for resistance to a necrosis-inducing isolate of Pyrenophora tritici-repentis located on 5BL of Triticum aestivum cv. Chinese Spring

Genome ◽  
1996 ◽  
Vol 39 (3) ◽  
pp. 598-604 ◽  
Author(s):  
W. S. Stock ◽  
A. L. Brûlé-Babel ◽  
G. A. Penner
Keyword(s):  
Triticum Aestivum ◽  
Resistance Gene ◽  
Chinese Spring ◽  
Recessive Gene ◽  
Triticum Aestivum L ◽  
Tan Spot ◽  
Monosomic Analysis ◽  
Chromosome Location ◽  
Pyrenophora Tritici Repentis ◽  
Chromosome Arm

Several sources of high-level resistance to tan spot caused by Pyrenophora tritici-repentis have been identified in hexaploid wheat (Triticum aestivum L.). This study was conducted to determine the number and chromosome location of a gene(s) in the cultivar Chinese Spring (CS) that confers resistance to a tan necrosis inducing isolate (nec+chl−) of P. tritici-repentis, 86-124, and insensitivity to Ptr necrosis toxin. Reciprocal crosses were made between CS (resistant–insensitive) and 'Kenya Farmer' (KF) (susceptible–sensitive). Analysis of the CS/KF F1and F2 populations and F2-derived F3 families identified a single nuclear recessive gene governing resistance to isolate 86-124 and Ptr necrosis toxin. Evaluation of the CS(KF) substitution series, F2 monosomic analysis, and screening of a series of 19 CS compensating nullitetrasomic and two ditelosomic lines (2AS and 5BL) indicated that the resistance gene was located on chromosome arm 5BL. No linkage exists between Lr18 and the tan necrosis resistance gene on chromosome arm 5BL. It is proposed that the gene for resistance to the tan necrosis inducing isolate 86-124 (nec+chl−) of P. tritici-repentis and Ptr necrosis toxin be named tsn1. Key words : wheat, Triticum aestivum L., tan spot resistance, Pyrenophora tritici-repentis (Died.) Drechs., chromosome location, Ptr necrosis toxin.

scholarly journals Health of leaves and ears of spring wheat (Triticum aestivum L.) cultivated after different forecrops

2013 ◽  
Vol 57 (1-2) ◽  
pp. 119-129
Author(s):  
Barbara Majchrzak ◽  
Tomasz P. Kurowski ◽  
Adam Okorski
Keyword(s):  
Spring Wheat ◽  
Triticum Aestivum L ◽  
Mycosphaerella Graminicola ◽  
Camelina Sativa ◽  
Brown Rust ◽  
Leaf Blotch ◽  
Ear Blight ◽  
Phaeosphaeria Nodorum ◽  
False Flax ◽  
Glume Blotch

The research was conduced in the years 2000-2002. The aim of the research was to determinate the health of leaves and ears of spring wheat cultivated after spring cruciferae plants such as: spring oilseed rape (<i>Brassica napus</i> ssp. <i>oleiferus</i> Metz.), chiiiese mustard (<i>Brassica juncea</i> L.), white mustard (<i>Sinapis alba</i> L.), ole iferous radish (<i>Raphanus sativus</i> var. <i>oleiferus</i> L.), false flax (<i>Camelina sativa</i> L.), crambe (<i>Crambe abbysinica</i> Hoechst.), as well as after oat (<i>Avena sativa</i> L.) as con trol. Spring wheat cv. Torka was sown after: pIoughed stubble cultivated on this field, ploughed stubble and straw, ploughed stubble with straw and 30 kg nitrogen per hectare. During all the years of studies on leaves and ears of spring wheat septo ria of leaf blotch and glume blotch (<i>Mycosphaerella graminicola, Phaeosphaeria nodorum</i>) were found. Brown rust (<i>Puccinia recondita</i> f. sp. <i>tritici</i>) was seen on leaves of wheat only during years 2001-2002. Besides on ears fusarium ear blight (Fusarimn sp.) was present in 2002 and sooty mould (<i>Cladosporium sp., Alternaria</i> sp.) in 2001. According to health of overground parts of plants the good forecrops to spring wheat were oat, chinese mustard, oleiferous radish. The biggest impact on presence of diseases of leaves and ears had the weather during years of studies. The use of after harvest rests didn't have significant influence on health of leaves and ears of spring wheat.

Identification of a major QTL for yellow leaf spot resistance in the wheat varieties Brookton and Cranbrook

2004 ◽  
Vol 55 (3) ◽  
pp. 315 ◽  
Author(s):  
J. Cheong ◽  
H. Wallwork ◽  
K. J. Williams
Keyword(s):  
Microsatellite Markers ◽  
Leaf Spot ◽  
Bulked Segregant Analysis ◽  
Tan Spot ◽  
Resistance Locus ◽  
Yellow Leaf ◽  
Wheat Varieties ◽  
Seedling Resistance ◽  
Pyrenophora Tritici Repentis ◽  
Chromosome 5B

Yellow leaf spot (YLS) or tan spot, caused by Pyrenophora tritici-repentis, is a major foliar disease of wheat. A bioassay was used to identify YLS seedling resistance phenotypes of Krichauff/Brookton and Cranbrook/Halberd doubled-haploid (DH) populations. Bulked-segregant analysis was used to identify amplified fragment length polymorphism (AFLP) markers linked to a YLS resistance locus in the wheat cultivar Brookton. Three AFLPs were linked to YLS resistance and also to each other. One of these AFLPs was mapped to the interval Xbcd351–Xcdo400, which has been assigned to chromosome 5BL. Microsatellite markers in this region were selected from several maps and were genotyped on the Krichauff/Brookton population. Together with the bulked segregant analysis (BSA)-derived AFLPs, the microsatellite markers explained up to 39% of the total phenotypic variation (logarithm of odds ratio, LOD ≥� 7.32), confirming the chromosome 5BL assignment of a Brookton YLS resistance locus, at or near the previously identified Pyrenophora tritici-repentis toxin-insensitivity locus tsn1. The marker–trait linkage was validated in the Cranbrook/Halberd DH population, in which the same microsatellite markers explained up to 60% of the total trait variance for YLS. The markers identified can be used for the selection of the Brookton and Cranbrook YLS seedling resistance locus on chromosome 5B.

scholarly journals First Report of a Leaf Spot on Hazel Leaves Caused by Phyllosticta coryli in Liaoning Province of China

Plant Disease ◽  
2013 ◽  
Vol 97 (9) ◽  
pp. 1254-1254 ◽  
Author(s):  
J. Sun ◽  
D.-M. Wang ◽  
X.-Y. Huang ◽  
Z.-H. Liu
Keyword(s):  
Leaf Spot ◽  
Control Strategies ◽  
Morphological Characteristics ◽  
Leaf Tissue ◽  
Its Region ◽  
Liaoning Province ◽  
Single Spore ◽  
First Report ◽  
Leaf Spots ◽  
Microscopic Morphology

Hazel (Corylus heterophylla Fischl) is an important nut tree grown in China, especially in Liaoning Province, and is rich in nutritional and medicinal values. In August 2011, leaf spotting was observed on hybrid hazel (Dawei) leaves in Paotai Town, Wafangdian County of Liaoning Province. By August 2012, the disease had spread to Zhangdang Town, Fushun County. Symptoms initially appeared on both sides of leaves as pinpoint brown spots, which enlarged and developed into regular, dark brown lesions, 3 to 9 mm in diameter. The lesions were lighter in color in the center compared to the margin. To identify the pathogen, leaf pieces (3 to 5 mm) taken from the margins, including both symptomatic and healthy portions of leaf tissue, were surface-disinfected first in 75% ethanol for 5 s, next in 0.1% aqueous mercuric chloride for 50 s, and then rinsed with sterilized water three times. Leaf pieces were incubated on potato dextrose agar (PDA) at 25°C for 14 days in darkness. Single spore isolates were obtained from individual conidia. For studies of microscopic morphology, isolates were grown on synthetic nutrient agar (SNA) in slide cultures. Colonies grew up to 45 to 48 mm in diameter on PDA after 14 days. Pycnidia appeared on the colonies after 12 days. Conidiophores were short. Pycnidia were dark brown, subglobose, and 150 to 205 μm in diameter. Conidia were unicellular, colorless, ovoid to oval, and from 2.4 to 4.5 × 1.6 to 2.4 μm. On the basis of these morphological characteristics, the isolates were tentatively identified as Phyllosticta coryli Westend (2). The rDNA internal transcribed spacer (ITS) region was amplified using primers ITS1 and ITS4 and sequenced (GenBank Accession No. KC196068). The 490-bp amplicons had 100% identity to an undescribed Phyllosticta species isolated from Cornus macrophylla in Gansu, Tianshui, China (AB470897). On the basis of morphological characteristics and nucleotide homology, the isolate was tentatively identified as P. coryli. Koch's postulates were fulfilled in the growth chamber on hazelnut leaves inoculated with P. coryli conidial suspensions (107 conidia ml–1). Eight inoculated 1-year-old seedlings (Dawei) were incubated under moist conditions for 8 to 10 days at 25°C. All leaf spots that developed on inoculated leaves were similar in appearance to those observed on diseased hazel leaves in the field. P. coryli was recovered from lesions and its identity was confirmed by morphological characteristics. P. coryli was first reported as a pathogen of hazel leaves in Bull of Belgium (2). In China, P. coryli was first reported on Corylus heterophylla Fisch. in Jilin Province (1). To our knowledge, this is the first report of P. coryli causing leaf spot on hybrid hazel in Liaoning Province of China. The outbreak and spread of this disease may decrease the yield of hazelnut in northern regions of China. More studies are needed on control strategies, including the possible resistance of hazel cultivars to P. coryli. References: (1) Y. Li et al. J. Shenyang Agric. Univ. 25:153, 1994. (2) P. A. Saccardo. Sylloge Fungorum Vol. III, page 31, 1884.

scholarly journals Yellow leaf spot of winter bread wheat in the Saratov region

2020 ◽  
pp. 67-71
Author(s):  
E. A. Konkova ◽  
S. V. Lyashcheva
Keyword(s):  
Bread Wheat ◽  
Causative Agent ◽  
Leaf Spot ◽  
Wheat Variety ◽  
Tan Spot ◽  
Soft Wheat ◽  
Yellow Leaf ◽  
Saratov Region ◽  
Pyrenophora Tritici Repentis ◽  
Winter Bread Wheat

The purpose of the current work was to study the development of tan spot, the causative agent of yellow leaf spot Pyrenophora tritici-repentis (Died) Drechsler on winter bread wheat in the conditions of the Saratov region of Russia. In 2018–2019 there was carried out an estimation of the resistance of 33 winter bread wheat samples to the causative agent of yellow leaf spot. It was established that the varieties “Gostianum 237” and “Levoberezhnaya 1” were characterized by a high level of resistance in the fields. There were identified such weak susceptible varieties as “Victoria 95”, “Gubernia”, “Mironovskaya 808”, “Donskaya bezostaya”, “Smuglyanka”, “Kalach 60”, “111-96 / Zhemchuzhina Povolzhiya”, “L 329 / Urozhaynaya”, “Gubernia / Zhemchuzhina Povolzhiya”, “Saratovskaya 90/ Ukraina”, “L 503 / M Freeman”, “81-93 / (Saratovskaya 11 / Kharkov 82)”. There was identified a moderate damage in the varieties “Lutenscens 230”, “Saratovskaya 80”, “Saratovskaya 90 / 14431 M”, “Sozvesdie”, “Anastasia”, “Saratovskaya 8 / Yubilyar”. The varieties “Zhemchuzhina Povolzhiya”, “Saratovskaya 17”, “Elvira”, “Saratovskaya 8 / B.Z.D.”, “(26-72 / N 49)/(L 15 / Pia)/Sar. 8)”, “Saratovskaya 8 / Yubilyar”, “L 503 / M Freeman”, “30-99/(Saratovskaya 11 / Kharkovskaya 82)”, “Sharada / L 31-98”, “346-06 / L 1334-5”, “Saratovskaya 90”, “L 329 / Saratovskaya ubileynaya”, “Istok/(Saratovskaya 90 / L 503)”, “Brigantina / Don 74” were found susceptible to the pathogen. It was identified that the proportion of winter soft wheat samples resistant to Pyrenophora tritici-repentis was 42% of the total number of varieties studied. There was studied dynamics of Pyrenophora tritici-repentis development in the winter soft wheat variety “Saratovskaya90”. It was found out that the damage degree of the winter bread wheat variety “Saratovskaya90” greatly depended upon the remoteness of the sowings from the source of infection.

scholarly journals First Report of Hainesia lythri Causing Leaf Spots of Paeonia suffruticosa in China

Plant Disease ◽  
2008 ◽  
Vol 92 (3) ◽  
pp. 486-486
Author(s):  
M. Zhang ◽  
H. L. Li ◽  
A. L. Zhao ◽  
J. X. Zhang
Keyword(s):  
Leaf Spot ◽  
Leaf Tissue ◽  
Causal Agent ◽  
Plant Diseases ◽  
Acer Pseudoplatanus ◽  
Paeonia Suffruticosa ◽  
Tree Peony ◽  
Korean Society ◽  
First Report ◽  
Leaf Spots

Tree peony (Paeonia suffruticosa) is known as “the king of flowers” for its beautiful and showy flowers. It is regarded as the symbol flower of China and is cultivated throughout the country. During the summer of 2006, a leaf spot was observed on tree peony cultivated in the Zhengzhou area of Henan Province, and in 2007, the leaf spot was observed in the Luoyang area. In some gardens, the leaf spot affected more than 50% of the plants. Early symptoms appeared as small, round, water-soaked lesions on the leaves. Lesions expanded into 5 to 35-mm-diameter spots that were circular or irregular, brown to dark brown, with pale brown margins. Later, the center of some lesions dropped out. Signs of the suspected pathogen were usually seen on the leaf spots after an abundant rainfall. Lesions contained numerous, pale brown, cupulate conidiomata with salmon-colored spore masses. Conidiophores (70 × 1 to 2 μm) were hyaline, branched, septate, and filiform. Conidia (5.5 to 7.5 × 1.5 to 2 μm) were hyaline, aseptate, and cymbiform to allantoid. The pathogen was identified as Hainesia lythri on the basis of the morphology. This fungus infects a wide variety of hosts including P. suffruticosa, Acer pseudoplatanus, Calluna sp., Dissotis paucistellata, Epilobium angustifolium, and Eucalyptus saligna (3). The fungus was isolated on potato dextrose agar (PDA) medium using conidia from conidiomata found on symptomatic leaf tissue; the fungus produced gray-to-brown colonies. Pathogenicity was tested by inoculating 10 leaves on one 5-year-old tree with a mycelia plug from the colony (0.5 cm in diameter); leaves inoculated with plugs of PDA medium served as controls. Inoculated leaves were covered with plastic for 24 h to maintain high relative humidity and incubated at 25 to 28°C. After 5 days, 100% of the inoculated leaves showed symptoms identical to those observed on leaves from P. suffruticosa infected in the field while controls remained symptom free. Reisolation of the fungus from lesions on inoculated leaves confirmed that the causal agent was H. lythri. Thus, we concluded that H. lythri is the causal agent of leaf spots of P. suffruticosa. To our knowledge, this is the first report of H. lythri infecting P. suffruticosa in China. H. lythri has been previously reported on Paeonia in Japan and Korea (1,2). References: (1) W. D. Cho and H. D. Shin, eds. List of Plant Diseases in Korea. 4th ed. Korean Society of Plant Pathology, 2004. (2) M. E. Palm. Mycologia 83:787, 1991. (3) B. C. Sutton. The Coelomycetes. CAB International Publishing, New York, 1980.

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