Reduced growth and deterrence from feeding of the insect pest Helicoverpa armigera associated with fungal endophytes from cotton

2002 ◽  
Vol 42 (7) ◽  
pp. 995 ◽  
Author(s):  
P. A. McGee
Keyword(s):  
Helicoverpa Armigera ◽  
New South ◽  
Insect Pest ◽  
Fungal Endophytes ◽  
Larval Growth ◽  
Fungal Endophyte ◽  
South Wales ◽  
Feeding Choice ◽  
Helicoverpa Armígera ◽  
The Impact

More than 13 morphospecies of fungal endophyte were isolated from leaves of cotton collected from eastern New South Wales, Australia. Of the fungi tested, methanol extracts of 4 morphospecies offered with a food source reduced the larval growth rate of the insect pest Helicoverpa armigera. Extracts of different isolates of 1�common morphospecies had varying effects on growth rates of H. armigera and H. punctigera. The impact of the endophytes after inoculation to leaves of cotton also differed. Five of 10 selected isolates were associated with reduced feeding from leaf discs in a feeding-choice experiment with H. armigera. The data are consistent with the view that some fungal endophytes benefit their host through reduced herbivory of the plant.

Pyrethroid and carbamate resistance in Australian Helicoverpa armigera (Lepidoptera: Noctuidae) from 2008 to 2015: what has changed since the introduction of Bt cotton?

2018 ◽  
Vol 108 (6) ◽  
pp. 781-791 ◽  
Author(s):  
L.J. Bird
Keyword(s):  
Helicoverpa Armigera ◽  
Pyrethroid Resistance ◽  
New South ◽  
Resistance Management ◽  
Rapid Expansion ◽  
Bt Cotton ◽  
South Wales ◽  
Helicoverpa Armígera ◽  
High Level ◽  
Lepidoptera Noctuidae

AbstractPyrethroid and carbamate resistance was evaluated in Helicoverpa armigera from 2008 to 2015. Insects were collected as eggs primarily from cultivated hosts in the major cropping areas of New South Wales and Queensland, Australia. Larvae reared from eggs were tested for resistance to fenvalerate, bifenthrin or methomyl in the F0 generation using a topical application of a discriminating dose of insecticide. In 2008–2009, resistance to fenvalerate was 71% and no resistance to bifenthrin was recorded. In the following two seasons, resistance to pyrethroids was relatively stable with fenvalerate resistance ranging from 63% to 67% and bifenthrin resistance ranging from 5.6% and 6.4% in 2009–2010 and 2010–2011, respectively. However, in 2011–2012, pyrethroid resistance had increased to 91% and 36% for fenvalerate and bifenthrin, respectively. Resistance remained above 90% for fenvalerate and above 35% for bifenthrin in the following three seasons from 2012 to 2015. In 2008–2009, methomyl resistance was 33% and declined to 22% and 15% in 2009–2010 and 2010–2011, respectively. Methomyl resistance remained at moderate levels from 2011–12 to 2014–15, ranging from 21% to 40%. Factors that influenced selection pressure of pyrethroid and carbamate insecticides and impacted resistance frequency in H. armigera may have been associated with changes in the composition of the cropping landscape. The rapid expansion of the pulse industry and the commensurate increased use of insecticide may have played a role in reselection of high-level pyrethroid resistance, and highlights the need for an urgent and strategic response to insecticide resistance management in the Australian grains industry.

The reproductive maturity and mating status of Helicoverpa armigera, H. punctigera and Mythimna convecta (Lepidoptera: Noctuidae) collected in tower-mounted light traps in northern New South Wales, Australia

1993 ◽  
Vol 83 (4) ◽  
pp. 529-534 ◽  
Author(s):  
M. Coombs ◽  
A. P. Del Socorro ◽  
G. P. Fitt ◽  
P. C. Gregg
Keyword(s):  
Helicoverpa Armigera ◽  
New South ◽  
New South Wales ◽  
Life History Strategies ◽  
Heterogeneous Environments ◽  
Light Traps ◽  
Mating Status ◽  
South Wales ◽  
North Eastern ◽  
Helicoverpa Armígera

AbstractThe reproductive condition and mating status of female Helicoverpa armigera (Hübner), H. punctigera (Wallengren) and the mating status of the armywormMythimna convecta (Walker), trapped in tower-mounted light traps were studied over a four and a half year period, from November 1985 to December 1989. The traps were mounted on towers (40 and 50 m high) in two geographically distinct sites, one located at Point Lookout and the other at Mt Dowe both in north-eastern New South Wales, Australia. At the Point Lookout site, 132 females of H. armigera and 366 of H. punctigera were examined and of those, 88.7% and 89.9% were unmated and immature, respectively. Most of the remaining females of both species were mature and mated. Of the matedH. armigerafemales, 78.6% carried only a single spermatophore, the remainder having either two or three spermatophores. Most of the matedH. punctigerafemales (97.1%) carried only a single spermatophore and the remainder had no more than two. Females ofM. convectawere predominantly (97.1%) unmated. At the Mt Dowe siteH. punctigeraadults were predominant and all 44 females of this species examined were unmated and non-gravid. Pre-reproductive flight byHelicoverpaspp. andM. convectais considered as an important component of the life-history strategies of these insects. Flexibility in the timing and spacing of reproductive effort is seen as enabling colonization of heterogeneous environments.

Seed production and seedling emergence of Giant Parramatta grass on the north coast of New South Wales

1996 ◽  
Vol 36 (3) ◽  
pp. 299 ◽  
Author(s):  
TS Andrews ◽  
RDB Whalley ◽  
CE Jones
Keyword(s):  
Seed Production ◽  
Seed Bank ◽  
New South ◽  
New South Wales ◽  
Seed Banks ◽  
North Coast ◽  
The North ◽  
South Wales ◽  
Seed Fall ◽  
The Impact

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.

Up the Garden Path? Enterprise Bargaining and Decentralization in the NSW Public Sector

1995 ◽  
Vol 37 (2) ◽  
pp. 203-217 ◽  
Author(s):  
Michael O'Donnell
Keyword(s):  
Public Sector ◽  
New South ◽  
Industrial Relations ◽  
New South Wales ◽  
Green Paper ◽  
Garden Path ◽  
Reform Agenda ◽  
The Public ◽  
South Wales ◽  
The Impact

Decentralizing industrial relations within New South Wales is a central recom mendation of the Niland Green Paper (1989). Decentralism also represents the cornerstone of the New South Wales government's industrial relations reform agenda enshrined in the New South Wales Industrial Relations Act 1991. To date there has been little analysis of the impact o f this legislative change on industrial relations in the New South Wales public sector. This paper provides a case study that examines the degree to which responsibility for bargaining has been devolved within the Parks and Gardens of the New South Wales Ministry for the Environ ment. It argues that, in contrast to the rhetoric of the New South Wales Act, the central agency presiding over the introduction of enterprise bargaining in the public sector, the Public Employment and Industrial Relations Authority; has been reluctant to delegate responsibility to parties in the workplace.

Cumulative reproductive performance effect on overall lifetime productivity in Merino sheep

2018 ◽  
Vol 58 (8) ◽  
pp. 1470
Author(s):  
J. S. Richards ◽  
M. A. Sladek ◽  
G. J. Lee
Keyword(s):  
Reproductive Performance ◽  
New South ◽  
Dental Health ◽  
Age Groups ◽  
The South ◽  
Performance Effect ◽  
South West ◽  
South Wales ◽  
The Impact ◽  
Effect Of Age

Reproduction is an important driver of profitability in commercial sheep flocks. Historically, Merino flocks have been run with a fixed age structure, ignoring individual merit and casting for age at a specific age. More recently, research has focussed on utilising the variation within age groups by keeping productive older ewes longer and culling less productive ewes earlier. Previous studies have also examined the effect of age on reproduction and the impact of reproduction status on productivity, but little research has been conducted on cumulative effects of reproductive performance on later productivity, reproduction and health. The present study examined the impact of higher lifetime reproduction on other key production and fitness traits in older ewes run under commercial conditions. Data were collected from two commercial wool-producing properties in the South West Slopes and the Central West Plains of New South Wales during 2009–2011. Reproduction, fleece measurements, bodyweight and condition and dental health were recorded during the study. The results showed that age had a bigger effect on productivity and dental health than did cumulative lifetime reproduction. Environment and genetics determined the level of impact, with minimal loss in productivity from increased age of animals occurring in the South West Slopes flock, whereas the Central West Plains flock would appear to require closer monitoring of productivity as ewes aged. The data collected did not allow separation of the genetic and environmental influences within the study. Retaining animals with a higher reproductive performance past normal culling age does not necessarily result in reduction of productivity or ewe health, but this must be monitored.

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