Black Point Of Wheat Caused By Bipolaris Sorokiniana And Its Management

The most effective and environmentally sustainable method for controlling black point disease of wheat (Triticum aestivum L.) is to plant resistant cultivars. To identify sources of resistance to black point, 165 selected cultivars/lines were inoculated with isolates of six fungal species (Bipolaris sorokiniana, Alternaria alternata, Fusarium equiseti, Exserohilum rostratum, Epicoccum sorghinum, and Curvularia spicifera) known to cause black point in wheat using spore suspensions under controlled field conditions in 2016 and 2017. Inoculation of the isolates significantly increased the incidence of black point in the cultivars/lines compared with those grown under natural field conditions (NFC). The disease incidence of plants inoculated with B. sorokiniana and E. rostratum was 15.5% and 18.8% in 2016, and 20.4% and 23.0% in 2017, whereas those under NFC were 5.7% (2016) and 1.5% (2017), respectively. Furthermore, disease symptoms varied with pathogen. Among the 165 cultivars/lines tested, 3.6%, 50.9%, 60.0%, 1.8%, 47.3%, and 58.8% were resistant to B. sorokiniana, A. alternata, F. equiseti, E. rostratum, E. sorghinum, and C. spicifera, respectively. In addition, we identified one line (‘SN530070’) resistant to black point caused by all six pathogens. This is the first study to assess resistance to wheat black point caused by six fungal species under controlled conditions. The black point-resistant cultivars/lines could be useful in breeding and also in research on the mechanisms of resistance to black point.

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Effect of black point disease on quality of wheat grain

Bangladesh Journal of Agricultural Research ◽

10.3329/bjar.v34i2.5789 ◽

1970 ◽

Vol 34 (2) ◽

pp. 181-187 ◽

Cited By ~ 1

Author(s):

PK Malaker ◽

IH Mian ◽

KA Bhuiyan ◽

MMA Reza ◽

MA Mannan

Keyword(s):

Fungal Pathogens ◽

Dry Matter ◽

Bipolaris Sorokiniana ◽

Wheat Grain ◽

Mineral Contents ◽

Black Point ◽

Nutrient Contents ◽

Calcium Magnesium ◽

Nitrogen Phosphorus

An experiment was conducted to determine the effect of different levels of black point infection caused by Bipolaris sorokiniana and other fungal pathogens on some quality characters of wheat grain. Wheat grains were graded on a 0-5 scale based on levels of black point infection. Quality characters of grain viz., protein, fat, dry matter, ash and mineral contents under different grades were determined following standard methods. The dry matter and ash contents of grain decreased while the contents of protein and fat increased with the increasing severity of black point infection. The observations on macro and micro nutrient contents of grain indicated that the amount of nitrogen, phosphorus, calcium, magnesium, sulphur, and boron increased, whereas the contents of potassium, iron, zinc, copper and sodium decreased with the increase of black point infection. However, the reductions in copper content of black point affected grains under different grades of infection were not significant as compared to apparently healthy grains. Key Words: Black point; Bipolaris sorokiniana; grain quality; wheat. DOI: 10.3329/bjar.v34i2.5789Bangladesh J. Agril. Res. 34(2) : 181-187, June 2009

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Enzymatic Browning in Wheat Kernels Produces Symptom of Black Point Caused by Bipolaris sorokiniana

Frontiers in Microbiology ◽

10.3389/fmicb.2020.526266 ◽

2020 ◽

Vol 11 ◽

Author(s):

Qiaoyun Li ◽

Kaige Xu ◽

Siyu Wang ◽

Mengyu Li ◽

Yumei Jiang ◽

...

Keyword(s):

Mass Spectrometry ◽

High Resolution Mass Spectrometry ◽

Bipolaris Sorokiniana ◽

Spectroscopic Properties ◽

Gas Chromatography Mass Spectrometry ◽

Enzymatic Browning ◽

Black Point ◽

Ft Ir ◽

Wheat Kernels

To understand the blackening mechanism in black point diseased kernels, ultraviolet–visible light (UV–Vis) and Fourier-transform infrared (FT-IR) absorbance spectra of extracts made from the blackening parts of black point-affected (BP) kernels and the analogous part of black point-free (BPF) kernels were measured using susceptible wheat genotypes “PZSCL6” inoculated with Bipolaris sorokiniana (the dominant pathogen causing this disease). In addition, metabolite differences between BP and BPF kernels were identified by a method that combines gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-high resolution mass spectrometry (LC-MS). Successively, symptoms of black point were produced in vitro. The results showed (i) the spectroscopic properties of the extracts from BP and BPF kernels were very similar, with an absorption peak at 235 nm and a small shoulder at 280–300 nm in both UV–Vis spectra and shared vibrations at 3400–3300, 2925 and 2852, 1512 and 1463, 1709, 1220, 600–860 cm–1 in FT-IR spectra that are consistent with similar bonding characteristics. In contrast, spectroscopic properties of extracts from wheat kernels were different from those of synthetic melanin and extracellular and intracellular melanin produced by B. sorokiniana. (ii) Levels of 156 metabolites in BP kernels were different from those in BPF kernels. Among those 156 metabolites, levels of phenolic acids (ferulic acid and p-coumaric acid), 11 phenolamides compounds, and four benzoxazinone derivatives were significantly higher in BP kernels than in BPF kernels. (iii) Symptom of black point could be produced in vitro in wheat kernels with supplement of phenol substrate (catechol) and H2O2. This result proved that blackening substance causing symptom of black point was produced by enzymatic browning in wheat kernels instead of by B. sorokiniana.

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Transcriptome-based analysis of resistance mechanism to black point caused by Bipolaris sorokiniana in wheat

Scientific Reports ◽

10.1038/s41598-021-86303-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Qiaoyun Li ◽

Chuang Gao ◽

Kaige Xu ◽

Yumei Jiang ◽

Jishan Niu ◽

...

Keyword(s):

Oxidative Stress ◽

Resistance Mechanism ◽

Bipolaris Sorokiniana ◽

Resistance Mechanisms ◽

Post Inoculation ◽

Biological Processes ◽

Black Point ◽

Oxidation Reduction ◽

Stress Oxidative ◽

Wheat Lines

AbstractBlack point is a cereal disease caused by complex pathogens, of which the pathogenicity of Bipolaris sorokiniana is the most serious in wheat. Resistance to black point is quantitative in nature, and thus the mechanism is poorly understood. We conducted a comparative transcriptome analysis to identify differentially expressed genes (DEGs) in black point-slightly susceptible and -highly susceptible wheat lines at different timepoints following B. sorokiniana inoculation. DEGs associated with photosynthesis were upregulated in black point-slightly susceptible lines. The top Gene Ontology enrichment terms for biological processes were oxidation–reduction, response to cold, salt stress, oxidative stress, and cadmium ion; terms for cellular component genes were mainly involved in plasma membrane and cytoplasmic membrane-bounded vesicle, whereas those for molecular function were heme binding and peroxidase activity. Moreover, activities of antioxidant enzymes superoxide dismutase, catalase, and peroxidase were higher in slightly susceptible lines than those in highly susceptible lines (except peroxidase 12–24 days post-inoculation). Thus, resistance to B. sorokiniana-caused black point in wheat was mainly related to counteracting oxidative stress, although the specific metabolic pathways require further study. This study presents new insights for understanding resistance mechanisms of selected wheat lines to black point.

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Effect of storage containers and time on seed quality of wheat

Bangladesh Journal of Agricultural Research ◽

10.3329/bjar.v33i3.1606 ◽

1970 ◽

Vol 33 (3) ◽

pp. 469-477 ◽

Cited By ~ 8

Author(s):

PK Malaker ◽

IH Mian ◽

KA Bhuiyan ◽

AM Akanda ◽

MMA Reza

Keyword(s):

Seed Germination ◽

Moisture Content ◽

Seed Quality ◽

Storage Period ◽

Bipolaris Sorokiniana ◽

Monthly Interval ◽

Curvularia Lunata ◽

Seed Moisture Content ◽

Black Point ◽

Wheat Seeds

A study was undertaken to determine the prevalence of black point and percentages of germination, moisture content and different fungi associated with wheat seeds during storage in different types of container. Seeds of a widely cultivated variety Kanchan were stored in five types of containers viz., âdole'(bamboo made), earthen pitcher, tin container, polyethylene bag and refrigerator (10Â°C) for ten months at room temperature. Samples were taken at monthly interval beginning from the month of April (prior to storage). The seed moisture content and black point severity were found highest in dole resulting in the lowest percentage of seed germination. The highest germination percentage was observed under storage in refrigerator followed by polyethylene bag, tin container and earthen pitcher. The moisture content and black point infection increased and seed germination decreased with the increase of storage period. Prior to storage in April, the seed germination was 95%, which decreased to about 75% at the end often months of storage (in January). Various fungal flora associated with wheat seeds differed in their prevalence depending on the length of storage period and types of container used for storage. The population of field fungi viz., Alternaria alternata, Aiternaria triticina, Bipolaris sorokiniana, Cladosporium cladosporioides, Curvularia lunata, Epicoccum purpurascens and Fusarium spp. decreased while that of storage fungi viz., Aspergillus, Chaetomium, Nigrospora, Penicillium and Rhizopus increased with the progress of storage period. Key Words: Storage, seed quality, wheat. doi:10.3329/bjar.v33i3.1606 Bangladesh J. Agril. Res. 33(3) : 469-477, September 2008

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Bipolaris sorokiniana-Induced Black Point, Common Root Rot, and Spot Blotch Diseases of Wheat: A Review

Frontiers in Cellular and Infection Microbiology ◽

10.3389/fcimb.2021.584899 ◽

2021 ◽

Vol 11 ◽

Author(s):

Abdullah M. Al-Sadi

Keyword(s):

Root Rot ◽

Seed Quality ◽

Bipolaris Sorokiniana ◽

Spot Blotch ◽

Crown Rot ◽

Common Root ◽

Black Point ◽

Common Root Rot ◽

The World ◽

Different Parts

Wheat is among the ten top and most widely grown crops in the world. Several diseases cause losses in wheat production in different parts of the world. Bipolaris sorokiniana (teleomorph, Cochliobolus sativus) is one of the wheat pathogens that can attack all wheat parts, including seeds, roots, shoots, and leaves. Black point, root rot, crown rot and spot blotch are the main diseases caused by B. sorokiniana in wheat. Seed infection by B. sorokiniana can result in black point disease, reducing seed quality and seed germination and is considered a main source of inoculum for diseases such as common root rot and spot blotch. Root rot and crown rot diseases, which result from soil-borne or seed-borne inoculum, can result in yield losses in wheat. Spot blotch disease affects wheat in different parts of the world and cause significant losses in grain yield. This review paper summarizes the latest findings on B. sorokiniana, with a specific emphasis on management using genetic, chemical, cultural, and biological control measures.

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Black point in spring durum wheat under different environmental conditions

Ukrainian Journal of Ecology ◽

10.15421/2019_815 ◽

2019 ◽

Vol 9 (4) ◽

pp. 713-718

Author(s):

L. P. Khlebova ◽

N. V. Barysheva ◽

A. I. Ziborov ◽

I. A. Brumberg

Keyword(s):

Durum Wheat ◽

Weather Conditions ◽

Growing Season ◽

Steppe Zone ◽

Economic Loss ◽

Bipolaris Sorokiniana ◽

Forest Steppe ◽

Wheat Grain ◽

Black Point ◽

Negative Effect

The study of cereal seed mycocenosis is relevant in solving problems determining the production of healthy, environmentally friendly agricultural products. Black point of wheat grain is a disorder characterised by a brown-black discolouration at the embryo end of the kernel. It is found in all regions of durum wheat cultivation and it results in significant economic loss annually. We studied seven varieties of spring durum wheat that were grown in 2014-2019. The weather conditions of the growing season have a significant impact on the development of black point of durum wheat in the forest-steppe zone of the Altai Territory of Russia (South-Western Siberia). The defeat of seeds by a black point varied from 2.3% to 28.0% on average for varieties. To obtain high-quality grain that is not affected by this disease, phytosanitary measures are required that reduce the infection of seeds with phytopathogens and limit the development of the disease during the growing season. Analysis of the pathogenic composition of fungal microorganisms in seeds of spring durum wheat, formed in different vegetations, revealed the presence of representatives of Fusarium, Alternaria, Helminthosporium, Penicillium and Aspergillum with a predominance of the first 3 genera. We found the negative effect of Fusarium fungi on seed germination. In the field conditions of the forest-steppe of the Altai Territory, the development of a black point in durum wheat grain is determined by the colonization of seeds with Bipolaris sorokiniana. No correlation was found between the incidence of black point and the infection of seeds by Fusarium and Alternaria.

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