Alternaria toxins in weather-damaged wheat and sorghum in the 1995-1996 Australian harvest

1997 ◽  
Vol 48 (8) ◽  
pp. 1249 ◽  
Author(s):  
D. J. Webley ◽  
K. L. Jackson ◽  
J. D. Mullins ◽  
A. D. Hocking ◽  
J. I. Pitt

Weather-damaged wheat from northern New South Wales in 1995-96 was heavily infected with the fungus Alternaria alternata. The mycotoxins tenuazonic acid, alternariol, and alternariol monomethyl ether were detected at low levels which corresponded with the degree of A. alternata infection and the geographical location. Sorghum and undamaged wheat from the same region also showed moderate levels of A. alternata infection and low levels of tenuazonic acid but none of the other toxins. These mycotoxins were not found in weather-damaged wheat from other areas of Australia where the primary infection was by A. infectoria rather than A. alternata.

2008 ◽  
Vol 71 (6) ◽  
pp. 1262-1265 ◽  
Author(s):  
M. P. AZCARATE ◽  
A. PATRIARCA ◽  
L. TERMINIELLO ◽  
V. FERNÁNDEZ PINTO

The natural occurrence of Alternaria mycotoxins in Argentinean wheat from the zone 5 South during the 2004 to 2005 harvest was investigated in 64 wheat samples. All samples were highly contaminated with a wide range of fungal species. Alternaria was found as the main component of the mycota, with an infection percentage of 100%. Three mycotoxins produced by species of Alternaria were determined in wheat: alternariol, alternariol monomethyl ether, and tenuazonic acid. Alternariol was detected in 4 (6%) of 64 samples, with a range of 645 to 1,388 μg/kg (mean of 1,054 μg/kg); alternariol monomethyl ether, with a range of 566 to 7,451 μg/kg (mean of 2,118 μg/kg) in 15 (23%) of 64 samples; and tenuazonic acid in 12 (19%) of 64 samples, with a range of 1,001 to 8,814 μg/kg (mean, 2,313 μg/kg). Alternariol monomethyl ether was the predominant toxin, but tenuazonic acid was detected in higher concentrations. Alternariol was present in fewer samples and in lower levels than were the other toxins. Tenuazonic acid and alternariol monomethyl ether occurred together in four samples, while tenuazonic acid and alternariol co-occurred in one sample. This the first report of the natural occurrence of Alternaria mycotoxins in Argentinean wheat. Toxin levels were high, probably due to the heavy infection with Alternaria species found in the samples.


1993 ◽  
Vol 56 (3) ◽  
pp. 246-248 ◽  
Author(s):  
V. SANCHIS ◽  
A. SANCLEMENTE ◽  
J. USALL ◽  
I. VIÑAS

The predominant fungal species present in 60 samples of barley collected in Spain were Alternaria alternata, Penicillium spp. and Aspergillus flavus. Of the 176 Alternaria isolates examined, 88.6% produced tenuazonic acid, 15.3% produced alternariol, and 9% produced alternariol monomethyl ether. Only 6% of the 190 isolates of A. flavus produced aflatoxin.


1993 ◽  
Vol 71 (1) ◽  
pp. 155-160 ◽  
Author(s):  
Hamed K. Abbas ◽  
R. F. Vesonder ◽  
C. D. Boyette ◽  
S. W. Peterson

Nine isolates of Alternaria alternata were obtained from infected tomato (cv. Beefsteak) plants. Each isolate was grown on autoclaved rice medium and corn meal agar medium and evaluated for pathogenesis and phytotoxicity to jimsonweed plants. Only A. alternata SWSL 1 (NRRL 18822) caused lodging on 1-week-old jimsonweed plants when sprayed at a rate of 20 g of fungus-infested rice per 100 mL distilled water. The symptoms began within 24 to 48 h following inoculation, and all plants were dead after 96 h. Treatment of 2-week-old jimsonweed plants in the same manner affected growth only. No symptoms occurred when SWSL 1 spores from corn meal agar were applied to jimsonweed at a rate of 2 × 107 spores/mL, with or without dew. The filtrates of fungus-infested rice of the SWSL 1 isolate were found to contain the following phytotoxins: AAL-toxin (100 μg/g), tenuazonic acid (10 μg/g), and alternariol monomethyl ether (580 μg/g). Crude and cell-free filtrates and AAL-toxin (concentration 200 μg/mL) caused similar damage on excised leaves, characterized by soft rot diffusing from the point of inoculation along the veins, adaxially or abaxially to leaves. Alternariol monomethyl ether (concentration 800 μg/mL) and tenuazonic acid (concentration 420 μg/mL) applied to excised jimsonweed leaves caused no visible damage. In intact plants, symptoms resulting from the crude filtrate, cell-free filtrate, and the AAL-toxin were identical. A dose–response study of AAL-toxin on excised jimsonweed and black nightshade (Solanum nigrum L.) leaves showed effects at concentrations of 1.56 μg/mL and 0.01 μg/mL, respectively. This is the first report of phytotoxicity of AAL-toxin to these two weeds and it may have potential as a weed control agent. Key words: weed, natural products, solid media, fungi.


1995 ◽  
Vol 58 (10) ◽  
pp. 1133-1134 ◽  
Author(s):  
SOFÍA N. CHULZE ◽  
ADRIANA M. TORRES ◽  
ANA M. DALCERO ◽  
MIRIAM G. ETCHEVERRY ◽  
MARÍA L. RAMÍREZ ◽  
...  

A survey of 150 sunflower-seed samples was carried out to evaluate the contamination from infection with Alternaria alternata with alternariol (AOH), alternariol monomethyl ether (AME) and tenuazonic acid (TA). A high percentage of the samples was contaminated with AOH (85%), AME, (47%), and TA (65%). The average levels detected were 187 μg/kg for AOH, 194 μg/kg for AME, and 6,692, μg/kg for TA. When sunflower seeds fermented by Alternaria alternata were processed under laboratory conditions to obtain the oil and meal, different distributions of Alternaria toxins between the oil and the meal were observed: whereas AOH, AME, and TA were detected in the meal, only AME and TA were detected in the oil, and the latter in a low percentage.


2001 ◽  
Vol 14 (2) ◽  
pp. 175 ◽  
Author(s):  
Andrew C. Rozefelds ◽  
Richard W. Barnes ◽  
Belinda Pellow

The vegetative and reproductive morphology of Vesselowskya Pampanini, southern marara, is described and illustrated in detail. The variation within V. rubifolia (F.Muell.) Pampanini sens. lat. is shown to be greater than has previously been recognised, with the differences identified supporting the recognition of a new segregate species, V. venusta Rozefelds, R.W.Barnes and Pellow sp. nov. Vesselowskya venusta occurs in the Barrington Tops Plateau of New South Wales and differs from V. rubifolia in possessing hairs on the abaxial surface of the sepals and lacking both a prominent distal connective protrusion on the anthers and colleters at the base of the stipules. The two Vesselowskya species are dioecious with a vestigial ovary in staminate flowers and reduced stamens in pistillate flowers. Dioecy is more pronounced in Vesselowskya, than in some Weinmannia species, and in both genera is expressed through reduction in the size of the ovaries in staminate flowers, and stamens in pistillate flowers. Vesselowskya shares with the other genera in the tribe Cunonieae (Pancheria, Weinmannia and Cunonia), a central column in the fruits, and Cunonia-type stipules, but differs from these genera in having valvate aestivation, digitate leaves, craspedodromous secondary venation with secondary veins terminating at a tooth, tuft domatia along the midrib, adaxial epidermal cells with strongly sinuous cell walls and the absence of hydathodes.


1969 ◽  
Vol 9 (40) ◽  
pp. 541 ◽  
Author(s):  
PW Grogan ◽  
DS Teakle

Seven out of eight maize inbred lines developed at Lawes in Queensland from open-pollinated varieties were resistant to maize dwarf mosaic disease when exposed to natural infection in the field. Five of the seven resistant inbred lines failed to become systemically infected when inoculated with infectious sap in the glasshouse. By contrast, only three out of twenty lines introduced from the U.S.A., and two out of eight lines developed at the Grafton and Glen Innes Breeding Stations in New South Wales, were resistant in the field. All three resistant lines from the U.S.A. were systemically infected when inoculated in the glasshouse, but the two resistant lines from Grafton in New South Wales were not. The resistant Lawes and Grafton maize inbred lines would appear to be better sources of genes conferring resistance to maize dwarf mosaic disease than the other lines tested.


1967 ◽  
Vol 7 (24) ◽  
pp. 7 ◽  
Author(s):  
P McInnes ◽  
TJ Grainger ◽  
MD Smith

Data are presented on the recovery and reproductive performance of 2 1/2-year-old maiden Merino ewes after a prolonged period of undernutrition. The 217 sheep had been hand-fed on a submaintenance ration in pen feeding trials at Glenfield, New South Wales. During the seven months of the trials they had lost 6 kg (28 to 22 kg) body weight. They were transported to Condobolin in south-western New South Wales, divided into two treatment groups and run on good quality pastures. One group was joined immediately (May 1959) and again ten months later, and the other group was mated after six months at Condobolin (in October 1959) and again 12 months later. The ewes recovered rapidly. The mean weight of both groups had reached 30 kg within six weeks and 40 kg within six months. In the first year 73 of the 100 May-mated ewes bore lambs, but only 38 of these lambs were weaned. Ewes bearing lambs had a higher body weight at the start of joining and gained more during joining than the barren ewes. At the other three joinings (October 1959, May 1960, October 1960) lambing percentage was from 86-89 and weaning percentage from 62-69-both normal for the district. The proportion of twin lambs (3-6 per cent) was low. Wool weight in 1959 was not affected by time of mating or by pregnancy.


Soil Research ◽  
1976 ◽  
Vol 14 (3) ◽  
pp. 381 ◽  
Author(s):  
GJ Osborne

Six surface and subsoils known to contain native intercalary ammonium were examined to assess the importance of ammonium fixation when nitrogen fertilizers were applied, the availability of native and recently fixed intercalary ammonium to plants, and the effect of potassium on fixation. Only one soil, a grey soil of heavy texture (Ug 5.4), fixed significant amounts of added ammonium sulphate, the level of intercalary ammonium being increased by 55 % in the surface and 100% in the subsoil. The native level of intercalary ammonium was reduced by 8 and 17% by the growth of plants in the red-brown earth (Dr 2.23) and the grey soil of heavy texture, respectively, but was unchanged in the other soils. The addition of small amounts of potassium prior to the ammonium did not affect fixation; however, additions of 500 ppm reduced the fixation of a 200 ppm solution of ammonium by 80 %. Intercalary ammonium is not considered to be important in the nitrogen economy of five of the six major farming soils of the slopes and plains area of southern New South Wales. The sixth, the grey soil of heavy texture, is an alluvium associated with the Murrumbidgee River and its tributaries, and as such is used extensively for irrigated agriculture. Because this soil can fix large amounts of ammonium, the use of ammonium or ammonium forming fertilizers is not recommended.


1998 ◽  
Vol 25 (4) ◽  
pp. 409 ◽  
Author(s):  
Damon L. Oliver

The dietary items fed to regent honeyeater, Xanthomyza phrygia, nestlings and fledglings by adults were recorded in two consecutive breeding seasons in the Bundarra–Barraba region west of Armidale, New South Wales. Insects were the most common dietary items fed to juveniles (53% of identified items), followed by lerp (26.5%) and nectar (20.5%). Nestlings were fed mostly insects (58% of feeds), and carbohydrates (nectar and lerp) made up the rest of their diet. Fledglings, however, were fed mainly carbohydrates (nectar and lerp comprised 61.2% of all items) while protein from insects was the other major component of their diet. Males tended to feed juveniles more insects than did females, although there were no significant divisions of labour between parents in selecting dietary items for nestlings or fledglings. This study highlights the importance of insects and lerp in the diet of juvenile regent honeyeaters, and the diversity of plant species on which their parents foraged. The species shows a broader resource selection than was found in previous studies which considered the species to be highly nectarivorous and selective for a few key eucalypt species. The importance of insects and carbohydrates other than nectar in the diet of the regent honeyeater needs to be recognised in the development of conservation strategies for the species.


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