Absence of detectable yield penalty associated with insensitivity to Pleosporales necrotrophic effectors in wheat grown in the West Australian wheat belt

Stagonospora nodorum is a major pathogen of wheat in many parts of the world and particularly in Western Australia. The pathosystem is characterised by interactions of multiple pathogen necrotrophic effectors (NE) (formerly host-specific toxins) with corresponding dominant host sensitivity loci. To date, five NE interactions have been reported in S. nodorum. Two proteinaceous NE (ToxA and SnTox3) have been cloned and expressed in microbial systems. The identification of wheat cultivars lacking sensitivity to one or more NE is a promising way to identify cultivars suitable for use in breeding for increased resistance to this economically important pathogen. The prevalence of sensitivity to the NE SnTox3 was investigated in 60 current Western Australian-adapted bread wheat (Triticum aestivum L.) cultivars. Infiltration of SnTox3 into seedling leaves caused a moderate or strong necrotic response in 52 cultivars. Six cultivars were insensitive and two cultivars exhibited a weak chlorotic response. Five of the cultivars that were insensitive or weakly sensitive to SnTox3 were noticeably more resistant to the disease. The 60 cultivars gave a very similar reaction to SnTox3 and to the crude S. nodorum SN15 culture filtrate demonstrating that SnTox3 is the dominant NE in this isolate. We conclude that a simple screen using both SnTox3 and ToxA effectors combined with simple greenhouse disease evaluation, will allow breeders to select cultivars that are more resistant to the disease, allowing them to concentrate resources on other still intractable breeding objectives.

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Sensitivity to three Parastagonospora nodorum necrotrophic effectors in current Australian wheat cultivars and the presence of further fungal effectors

Crop and Pasture Science ◽

10.1071/cp13443 ◽

2014 ◽

Vol 65 (2) ◽

pp. 150 ◽

Cited By ~ 20

Author(s):

Kar-Chun Tan ◽

Ormonde D. C. Waters ◽

Kasia Rybak ◽

Eva Antoni ◽

Eiko Furuki ◽

...

Keyword(s):

Fungal Pathogen ◽

Gene Interactions ◽

Wheat Cultivars ◽

Septoria Nodorum Blotch ◽

Effector Genes ◽

Australian Wheat ◽

Parastagonospora Nodorum ◽

Necrotrophic Effector ◽

Necrotrophic Effectors ◽

Western Australian

Parastagonospora nodorum is a major fungal pathogen of wheat in Australia, causing septoria nodorum blotch (SNB). Virulence of P. nodorum is quantitative and depends largely on multiple effector–host sensitivity gene interactions. The pathogen utilises a series of proteinaceous, necrotrophic effectors to facilitate disease development on wheat cultivars that possess appropriate dominant sensitivity loci. Thus far, three necrotrophic effector genes have been cloned. Proteins derived from these genes were used to identify wheat cultivars that confer effector sensitivity. The goal of this study was to determine whether effector sensitivity could be used to enhance breeding for SNB resistance. We have demonstrated that SnTox1 effector sensitivity is common in current commercial Western Australian wheat cultivars. Thirty-three of 46 cultivars showed evidence of sensitivity to SnTox1. Of these, 19 showed moderate or strong chlorotic/necrotic responses to SnTox1. Thirteen were completely insensitive to SnTox1. Disease susceptibility was most closely associated with SnTox3 sensitivity. We have also identified biochemical evidence of a novel chlorosis-inducing protein or proteins in P. nodorum culture filtrates unmasked in strains that lack expression of ToxA, SnTox1 and SnTox3 activities.

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Water and American Government: The Reclamation Bureau, National Water Policy, and the West, 19021935. By Donald J. Pisani. Berkeley: University of California Press, 2002. Pp. xviii, 394. $49.95.

The Journal of Economic History ◽

10.1017/s0022050703542322 ◽

2003 ◽

Vol 63 (3) ◽

pp. 906-908

Author(s):

MARK KANAZAWA

Keyword(s):

Water Policy ◽

University Of California ◽

American Government ◽

The West ◽

National Water

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Enumeration and Identification of Asbestos Fibres in Water

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010005264x ◽

1974 ◽

Vol 32 ◽

pp. 526-527 ◽

Cited By ~ 1

Author(s):

O. Mudroch ◽

J. R. Kramer

Keyword(s):

Water Supply ◽

Water Samples ◽

Drainage Basin ◽

Lake Superior ◽

Research Work ◽

List Type ◽

The West ◽

Asbestos Fibre ◽

Amphibole Asbestos

Approximately 60,000 tons per day of waste from taconite mining, tailing, are added to the west arm of Lake Superior at Silver Bay. Tailings contain nearly the same amount of quartz and amphibole asbestos, cummingtonite and actinolite in fibrous form. Cummingtonite fibres from 0.01μm in length have been found in the water supply for Minnesota municipalities.The purpose of the research work was to develop a method for asbestos fibre counts and identification in water and apply it for the enumeration of fibres in water samples collected(a) at various stations in Lake Superior at two depth: lm and at the bottom.(b) from various rivers in Lake Superior Drainage Basin.

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The fight to save Uganda’s White Rhino

Africana Newsletter ◽

10.1017/s0568160x00000125 ◽

1964 ◽

Vol 2 (01) ◽

pp. 6-12

Keyword(s):

The West ◽

West Nile ◽

White Rhino

In the West Nile District of Uganda lives a population of white rhino—those relies of a past age, cumbrous, gentle creatures despite their huge bulk—which estimates only 10 years ago, put at 500. But poachers live in the area, too, and official counts showed that white rhino were being reduced alarmingly. By 1959, they were believed to be diminished to 300.

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