Survey of fungi and nematodes associated with root and stolon diseases of white clover in the subtropical dairy region of Australia

2001 ◽  
Vol 41 (8) ◽  
pp. 1133 ◽  
Author(s):  
M. I. Zahid ◽  
G. M. Gurr ◽  
A. Nikandrow ◽  
M. Hodda ◽  
W. J. Fulkerson ◽  
...  

A survey of 12 white clover-based dairy pastures on the north coast of New South Wales and south-eastern Queensland, Australia, detected 65 species of fungi and 6 nematode species. The fungi included species of Fusarium, Gliocladium, Codinaea, Alternaria, Colletotrichum, Drechslera, Rhizoctonia, Phoma, Pythium, Phytophthora, Penicillium, Rhizopus and Trichoderma from roots and stolons of white clover. Fungal rots of roots and stolons were most severe during the summer months (November and January samples), while root-knot symptoms caused by plant parasitic nematodes were more severe in June. Sedentary endoparasitic nematodes Meloidogyne trifoliophila, Heterodera trifolii and the ectoparasitic nematode Helicotylenchus dihystera were the numerically dominant nematodes in the region. Other nematode species, including Pratylenchus, Xiphinema and Tylenchorhynchus, were present at lower frequencies and principal component analysis indicated that these were less important as white clover pathogens. Meloidogyne trifoliophila was detected for the first time in Australia and was present at all sites. Many of the fungi and nematodes found are common pathogens of white clover. These pathogens are likely to be contributing to the poor seedling performance, growth and persistence of white clover typical in dairy pastures of the subtropical east coast of Australia.

1970 ◽  
Vol 23 (3) ◽  
pp. 597 ◽  
Author(s):  
RN Allen ◽  
AC Hayward ◽  
WJ Halliday ◽  
Jean Fulcher

A serious new disease of vetch in the north coast area of New South Wales was shown to be caused by Pseudomonas stizolobii (Wolf) Stapp. The pathogen, recorded in Australia for tho first time, was able to infect eight other species of legumes in glasshouse tests. Field diseases of Trifolium repens and Mucuna sp. caused by this organism were also recorded and isolates obtained from these sources were found to be pathogenic to vetch.


1996 ◽  
Vol 36 (3) ◽  
pp. 299 ◽  
Author(s):  
TS Andrews ◽  
RDB Whalley ◽  
CE Jones

Inputs and losses from Giant Parramatta grass [GPG, Sporobolus indicus (L.) R. Br. var. major (Buse) Baaijens] soil seed banks were quantified on the North Coast of New South Wales. Monthly potential seed production and actual seed fall was estimated at Valla during 1991-92. Total potential production was >668 000 seeds/m2 for the season, while seed fall was >146000 seeds/m2. Seed fall >10000 seeds/m2.month was recorded from January until May, with further seed falls recorded in June and July. The impact of seed production on seed banks was assessed by estimating seed banks in the seed production quadrats before and after seed fall. Seed banks in 4 of the 6 sites decreased in year 2, although seed numbers at 1 damp site increased markedly. Defoliation from mid-December until February, April or June prevented seed production, reducing seed banks by 34% over 7 months. Seed banks in undefoliated plots increased by 3300 seeds/m2, although seed fall was estimated at >114 000 seeds/m2. Emergence of GPG seedlings from artificially established and naturally occurring, persistent seed banks was recorded for 3 years from bare and vegetated treatment plots. Sown seeds showed high levels of innate dormancy and only 4% of seeds emerged when sown immediately after collection. Longer storage of seeds after collection resulted in more seedlings emerging. Estimates of persistent seed banks ranged from 1650 to about 21260 seeds/m2. Most seedlings emerged in spring or autumn and this was correlated with rainfall but not with ambient temperatures. Rates of seed bank decline in both bare and vegetated treatment plots was estimated by fitting exponential decay curves to seed bank estimates. Assuming no further seed inputs, it was estimated that it would take about 3 and 5 years, respectively, for seed banks to decline to 150 seeds/m2 in bare and vegetated treatments.


Oceania ◽  
1957 ◽  
Vol 27 (3) ◽  
pp. 190-209 ◽  
Author(s):  
Malcolm J. C. Calley

Zootaxa ◽  
2006 ◽  
Vol 1222 (1) ◽  
pp. 1 ◽  
Author(s):  
LAUREN E. HUGHES ◽  
JAMES K. LOWRY

Nine new species of epibenthic amphipods are described from the Solitary Islands, mid-north coast, New South Wales, Australia. Material was collected on natural habitats and from a range of small plastic artificial substrates. Protohyale pusilla (Chevreux, 1907) is reported from Australia for the first time. The subgenus Telsosynopia Karaman, 1986 is given generic status and Regalia juliana Lowry & Springthorpe, 2005 is transferred to Tepidopleustes in the pleustid subfamily Austropleustinae. New species include: Protohyale solitaire sp. nov. (Hyalidae); Ericthonius rodneyi sp. nov. and Ericthonius forbesii sp. nov. (Ischyroceridae); Liljeborgia polonius sp. nov. (Liljeborgiidae); Elasmopus arrawarra sp. nov. and Hoho cornishi sp. nov. (Melitidae); Gammaropsis legoliath sp. nov. (Photidae); Tepidopleustes coffsiana sp. nov. (Pleustidae); and Telsosynopia trifidilla sp. nov. (Synopiidae).


1997 ◽  
Vol 166 (6) ◽  
pp. 290-293 ◽  
Author(s):  
Tim J Sladden ◽  
Alan R Hickey ◽  
Thérèse M Dunn ◽  
John R Beard

1994 ◽  
Vol 45 (3) ◽  
pp. 721 ◽  
Author(s):  
WJ Fulkerson ◽  
K Slack

This study on the north coast of New South Wales, Australia, evaluated the effect of irrigation and defoliation management over summer, pasture type and seedbed preparation on production and survival of a perennial ryegrass pasture over an 18-month period from sowing. In a relatively dry summer, irrigation sufficient only to keep plants growing, increased production of ryegrass plus clover from 2826 to 5515 and 3210 to 5396 kg DM/ha in summer and the subsequent autumn/winter, respectively, and increased survival of ryegrass plants by 34%. The more summer active Olwen white clover/NZA895 perennial ryegrass combination had a 16% higher production in summer, but a 11% lower production in winter than a Haifa/Yatsyn sward. The difference in production was entirely due to the clover component of the pasture. DM yield in the first growing season for the ryegrass/white clover pasture was equivalent to applying 20 kg N/ha/month to a pure ryegrass sward. In the subsequent summer/autumn/winter, the yield of pure ryegrass pasture was well below the ryegrass/white clover swards at any rate of N application. There was no difference between survival of NZA895 and Yatsyn ryegrass or incursion of summer grass into their respective plots. Plots defoliated over summer at 6 cm, as opposed to 12 cm, stubble height yielded 54% more edible DM and resulted in a 65% higher ryegrass plant survival rate. There was no effect on summer grass incursion. Multiple cultivations appear to be the key to appropriate seedbed preparation, with this treatment achieving the highest ryegrass survival rate, lowest summer grass incursion and highest DM yields.


Brunonia ◽  
1987 ◽  
Vol 10 (2) ◽  
pp. 201
Author(s):  
DJ Boland ◽  
DA Kleinig ◽  
JJ Brophy

A new species, Eucalyptus fusiformis Boland et Kleinig, from the north coast of New South Wales is described. Its taxonomic position is in E. subgenus Symphyomyrtus series Paniculatae following the informal classification of eucalypts proposed by Pryor and Johnson (1971). E. fusiformis is characterised by its flowers, fruits and adult leaves. In the bud the staminal filaments are fully inflected while the androecium has outer staminodes and the anthers are cuboid and adnate. The fruits are narrow, often truncate fusiform, tapering into long slender pedicels. The adult leaves are dull grey, concolorous and hypoamphistomatic. The species resembles the more numerous and often co-occurring ironbark E. siderophloia which has similar adult and seedling leaves. The volatile oils of both species are very similar. The ecology, distribution, taxonomic affinities and conservation status are discussed.


1997 ◽  
Vol 37 (4) ◽  
pp. 439 ◽  
Author(s):  
T. S. Andrews ◽  
C. E. Jones ◽  
R. D. B. Whalley

Summary. Four experiments were conducted to determine the effects of temperature, light and leaf extract solutions on the germination of Giant Parramatta grass [GPG, Sporobolus indicus (L.) R. Br. var. major (Buse) Baaijens] collected from a population on the North Coast of New South Wales. In the first experiment, seeds were subjected to one of a range of temperature combinations immediately after collection and again after 8 and 27 weeks. Germination was restricted to a narrow range of alternating temperatures with a peak at 35°C day/15°C night when seeds were tested immediately after collection. More seeds germinated when the samples had been stored, although germination remained depressed at constant temperatures. These data indicate that freshly collected GPG seeds are subject to primary dormancy and that few would germinate in the field immediately after seed fall. In a second experiment, seeds were buried beneath leaf litter in a pasture immediately after collection. After 7 months, the seeds were exhumed and subjected to either constant (20°C) or alternating (35/15°C) temperatures in either full light, reduced red:far-red (R : FR) light or dark treatments. Over 95% of GPG seeds germinated when subjected to alternating temperatures, regardless of light treatment. At constant temperatures, 97% of seeds germinated under full light, 59% at reduced R : FR light and <1% in dark treatments. A germination response to alternating temperatures and/or light treatments has been reported in pasture weeds and may be an adaptation to detecting gaps in the pasture canopy. Consequently, the germination of GPG in a pasture may be manipulated to some extent by altering the amount of pasture cover using grazing management, mowing and fertiliser applications. In experiment 3, leaves from a range of coastal grasses were mixed with water and the solutions were used to germinate GPG seeds. Solutions extracted from setaria (Setaria sphacelata) leaves completely inhibited GPG germination while 27% of GPG seeds germinated when imbibed with kikuyu leaf extract solution. Solution extracted from carpet grass (Axonopus affinis) leaves had the least effect on GPG germination. In experiment 4, the effects of solutions that had been leached from the leaves of either setaria or carpet grass on seed germination, and root and shoot lengths of GPG seedlings were compared. Germination was less inhibited by leachate solutions compared with the extract solutions used in experiment 3. Seedlings in setaria leachates had significantly shorter roots and shoots than both those germinated in carpet grass leachates and control seedlings. This may explain, at least in part, why carpet-grass-based pastures are readily infested with GPG while setaria-based pastures are relatively resistant to infestation. The potential for allelopathic interactions between GPG and setaria to be fully utilised to reduce the abundance of GPG in coastal New South Wales pastures is discussed.


1971 ◽  
Vol 11 (50) ◽  
pp. 307 ◽  
Author(s):  
GJ Murtagh

The effectiveness of chemical seedbed preparation for sod-sown oats was studied using varying intervals between spraying and sowing. Four herbicides were compared in a second experiment. Both experiments were conducted on paspalum (Paspalum dilatatum) dominant pastures on red basaltic soil on the North Coast of New South Wales. Herbicides were most effective when applied at 6.7 kg acid equivalent a hectare. At this rate, the highest yields of dry matter and nitrogen were obtained when there was a three-week interval and considerably less when there was no interval. A mixture of 2,2-DPA (2,2-dichloropropionic acid) and amitrole (3-amino-1,2,4-triazole) was more effective than 2,2-DPA alone with a three-week spraying interval but there was no difference with a six-week interval. Both amitrole and a mixture of amitrole and ammonium thiocyanate were ineffective for chemical seedbed preparation on paspalum pastures;


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