89 research outputs found
Alternative reproductive tactics and evolutionary rescue
Almost all life on earth is facing environmental change, and understanding how populations will respond to these changes is of urgent importance. One factor that is known to affect the speed by which a population can evolve when faced with changes in the environment is strong sexual selection. This increases the adaptive capacity of a population by increasing reproductive skew toward well-adapted (usually) males who will, on average, be best able to compete for matings. This effect could potentially be disrupted when males pursue alternative reproductive tactics (ARTs), whereby males within a species exhibit qualitatively different behaviors in their pursuit of matings. ARTs are diverse, but one common class is those expressed through condition-dependent polyphenism such that high-quality, well-adapted males compete aggressively for mates and low-quality, poorly adapted males attempt to acquire matings via other, nonaggressive behaviors. Here, using an individual-based modeling approach, we consider the possible impacts of ARTs on adaptation and evolutionary rescue. When the ART is simultaneous, meaning that low-quality males not only engage in contests but also pursue other tactics, adaptive capacity is reduced and evolutionary rescue, where a population avoids extinction by adapting to a changing environment, becomes less likely. This is because the use of the ART allows low-quality males to contribute more maladaptive genes to the population than would happen otherwise. When the ART is fixed, however, such that low-quality males will only use the alternative tactic and do not engage in contests, we find the opposite: adaptation happens more quickly and evolutionary rescue when the environment changes is more likely. This surprising effect is caused by an increase in the mating success of the highest quality males who face many fewer competitors in this scenarioâcounterintuitively, the presence of males pursuing the ART increases reproductive skew toward those males in the best condition
Sex ratio distorting microbes exacerbate arthropod extinction risk in variable environments
Maternally-inherited sex ratio distorting microbes (SRDMs) are common among arthropod species. Typically, these microbes cause female-biased sex ratios in host broods, either by; killing male offspring, feminising male offspring, or inducing parthenogenesis. As a result, infected populations can experience drastic ecological and evolutionary change. The mechanism by which SRDMs operate is likely to alter their impact on host evolutionary ecology; despite this, the current literature is heavily biased towards a single mechanism of sex ratio distortion, male-killing. Furthermore, amidst the growing concerns surrounding the loss of arthropod diversity, research into the impact of SRDMs on the viability of arthropod populations is generally lacking. In this study, using a theoretical approach, we model the epidemiology of an understudied mechanism of microbially-induced sex ratio distortionâfeminisationâto ask an understudied questionâhow do SRDMs impact extinction risk in a changing environment? We constructed an individual-based model and measured host population extinction risk under various environmental and epidemiological scenarios. We also used our model to identify the precise mechanism modulating extinction. We find that the presence of feminisers increases host population extinction risk, an effect that is exacerbated in highly variable environments. We also identified transmission rate as the dominant epidemiological trait responsible for driving extinction. Finally, our model shows that sex ratio skew is the mechanism driving extinction. We highlight feminisers and, more broadly, SRDMs as important determinants of the resilience of arthropod populations to environmental change
Genome size and ploidy influence angiosperm species' biomass under nitrogen and phosphorus limitation
Research Council of Norway. Grant Number: 196468/v40. NERC. Grant Number: NE/J012106/
Crop Updates 2002 - Cereals
This session covers thirty one papers from different authors:
VARIETIES AND BREEDING
1. Agronomic evaluation of wheat and barley in the central wheatbelt of Western Australia, Peter Burgess1and Gary Fawell2, 1Agritech and 2Farmanco Management
2. Evaluating stress tolerance to terminal drought by Western Australian wheats, Dean Diepeveen and Dr Tim Setter, Department of Agriculture
3. Broadscale wheat variety comparisons featuring Wyalkatchem, Jeff Russell, Department of Agriculture
4. Australian crop accreditation system variety selector, Tony Seymour, Australian Crop Accreditation System
5. Future wheat varieties, Robin Wilson, Iain Barclay,Robyn McLean, Robert Loughman, Jenny Garlinge, Bill Lambe, Neil Venn and Peter Clarke, Department of Agriculture
AGRONOMY
6. Beware of wheat variety interactions with row spacing and seed rate, Mohammad Amjad and Wal Anderson, Department of Agriculture
7. Yield and falling numbers of wheat varieties on the South Coast, Mohammad Amjad and Wal Anderson, Department of Agriculture
8. Maximising wheat variety performance through agronomic management, Wal Anderson, Raffaele Del Cima, James Bee, Darshan Sharma, Sheena Lyon, Melaine Kupsch, Mohammad Amjad, Pam Burgess, Veronika Reck, Brenda Shackley, Ray Tugwell, BindiWebb and Steve Penny Jr, Department of Agriculture
9. High impact of soil type and seasonal rainfall on optimum wheat seed rate , Raffaele Del Cima and Wal Anderson Department of Agriculture
10. 101 seasons in one day: Using the âWA Wheatâ database to predict wheat yield, James Fisher1, Bill Bowden1, Craig Scanlan1, Senthold Asseng2and Michael Robertson2 1Department of Agriculture, 2CSIRO
11. Economics of improving compact soils, M.A. Hamza1, G. McConnell2and W.K. Anderson1, 1Department of Agriculture, 2Planfarm
12. Reducing the risks in producing durum wheat in Western Australia, Md Shahajahan Miyan and Wal Anderson, Department of Agriculture
13. Taking the Why out of Wyalkatchem â the new widely adopted wheat variety, Steve Penny, Department of Agriculture
14. Influence of nutrition and environmental factors on seed vigour in wheat, Darshan Sharma, Wal Anderson and Daya Patabendige, Department of Agriculture
NUTRITION
15. N and K are important for oat yield and quality, Patrick Gethin, Stephen Loss, Tim OâDea, Ryan Guthrie and Lisa Leaver, CSBP Futurefarm
16. Effects of nitrogen and phosphorus on the grain yield and quality of noodle wheat, Tyrone Henning1, Lionel Martin1and Wal Anderson2 1Muresk Institute of Agriculture, 2Department of Agriculture
17. Assessment of a high input fertiliser regime on the yield and quality of Gairdner barley, Narelle Hill1, Simon Wallwork2and Laurence Carslake2 1Department of Agriculture, 2Wesfarmers Landmark
18. The use of Flexi-N to achieve high yielding, high protein wheat, Darren Hughes1, Lionel Martin1, Wal Anderson2and Stephen Loss3 1Muresk Institute of Agriculture, 2Department of Agriculture, 3CSBP Futurefarm
19. Are liquid phosphorus fertilisers more efficient than solid fertilisers in Western Australia?Stephen Loss, Lisa Leaver, Ryan Guthrie, Patrick Gethin and Tim OâDea, CSBP Futurefarm
20. Oats respond to phosphorus and potassium, Glenn McDonald, Department of Agriculture
PESTS AND DISEASES
21. Cereal disease diagnostics and rust monitoring, Nichole Burges and Dominie Wright, Department of Agriculture
22. Distribution and incidence of aphids and barley yellow dwarf virus in over-summering grasses in the Western Australian wheatbelt, Jenny Hawkes and Roger Jones, Centre for Legumes in Mediterranean Agriculture and Department of Agriculture
23. Spring sprays for powdery mildew control in cereals, Kith Jayasena1, Kazue Tanaka1, Vanessa Johnson1, Robert Loughman1and Josh Jury2 1Department of Agriculture, 2Wesfarmers Landmark
24. Impact of root lesion nematodes on wheat and triticale in Western Australia, Sean Kelly and Shashi Sharma, Department of Agriculture
25. Cropping options for the management of root lesion nematodes in Western Australia, Sean Kelly, Shashi Sharma and Robert Loughman, Department of Agriculture
26. Cereal rust update 2002 â new stem rust on Camm wheat, Robert Loughman1and Robert Park2 1Department of Agriculture, 2University of Sydney
27. Cereal aphids and direct feeding damage to cereals, Phil Michael, Department of Agriculture
28. A decision support system for control of aphids and BYDV in cereal crops, Debbie Thackray, Jenny Hawkes and Roger Jones, Department of Agriculture and Centre for Legumes in Mediterranean Agriculture
STORAGE
29. Aeration â opportunity for profit, Christopher Newman, Department of Agriculture
CLIMATE
30. Financial impact of frost on the Western Australian grains industry, Garren Knell and Kim Povey, ConsultAg
31. Summary of 2001 weather and seasonal prospects for 2002, David Stephens, Department of Agricultur
Voltinism and resilience to climate-induced phenological mismatch
SJT was supported by NERC grant NE/J02080X/
Crop Updates 2006 - Cereals
This session covers twenty nine papers from different authors:
PLENARY
1. The 2005 wheat streak mosaic virus epidemic in New South Wales and the threat posed to the Western Australian wheat industry, Roger Jones and Nichole Burges, Department of Agriculture
SOUTH COAST AGRONOMY
2. South coast wheat variety trial results and best options for 2006, Mohammad Amjad, Ben Curtis and Wal Anderson, Department of Agriculture
3. Dual purpose winter wheats to improve productivity, Mohammad Amjad and Ben Curtis, Department of Agriculture
4. South coast large-scale premium wheat variety trials, Mohammad Amjad and Ben Curtis, Department of Agriculture
5. Optimal input packages for noodle wheat in Dalwallinu â Liebe practice for profit trial, Darren Chitty, Agritech Crop Research and Brianna Peake, Liebe Group
6. In-crop risk management using yield prophetÂź, Harm van Rees1, Cherie Reilly1, James Hunt1, Dean Holzworth2, Zvi Hochman2; 1Birchip Cropping Group, Victoria; 2CSIRO, Toowoomba, Qld
7. Yield ProphetÂź 2005 â On-line yield forecasting, James Hunt1, Harm van Rees1, Zvi Hochman2,Allan Peake2, Neal Dalgliesh2, Dean Holzworth2, Stephen van Rees1, Trudy McCann1 and Peter Carberry2; 1Birchip Cropping Group, Victoria; 2CSIRO, Toowoomba, Qld
8. Performance of oaten hay varieties in Western Australian environments, Raj Malik and Kellie Winfield, Department of Agriculture
9. Performance of dwarf potential milling varieties in Western Australian environments, Kellie Winfield and Raj Malik, Department of Agriculture
10. Agronomic responses of new wheat varieties in the Southern agricultural region of WA, Brenda Shackley and Judith Devenish, Department of Agriculture
11. Responses of new wheat varieties to management factors in the central agricultural region of Western Australia, Darshan Sharma, Steve Penny and Wal Anderson,Department of Agriculture
12. Sowing time on wheat yield, quality and $ - Northern agricultural region, Christine Zaicou-Kunesch, Department of Agriculture
NUTRITION
13.The most effective method of applying phosphorus, copper and zinc to no-till crops, Mike Bolland and Ross Brennan, Department of Agriculture
14. Uptake of K from the soil profile by wheat, Paul Damon and Zed Rengel, Faculty of Natural and Agricultural Sciences, University of Western Australia
15. Reducing nitrogen fertiliser risks, Jeremy Lemon, Department of Agriculture
16. Yield ProphetÂź and canopy management, Harm van Rees1, Zvi Hochman2, Perry Poulton2, Nick Poole3, Brooke Thompson4, James Hunt1; 1Birchip Cropping Group, Victoria; 2CSIRO, Toowoomba, Qld; 3Foundation for Arable Research, New Zealand; 4Cropfacts, Victoria
17. Producing profits with phosphorus, Stephen Loss, CSBP Ltd, WA
18. Potassium response in cereal cropping within the medium rainfall central wheatbelt, Jeff Russell1, Angie Roe2 and James Eyres2, Department of Agriculture1, Farm Focus Consultants, Northam2
19. Matching nitrogen supply to wheat demand in the high rainfall cropping zone, Narelle Simpson, Ron McTaggart, Wal Anderson, Lionel Martin and Dave Allen, Department of Agriculture
DISEASES
20. Comparative study of commercial wheat cultivars and differential lines (with known Pm resistance genes) to powdery mildew response, Hossein Golzar, Manisha Shankar and Robert Loughman, Department of Agriculture
21. On farm research to investigate fungicide applications to minimise leaf disease impacts in wheat â part II, Jeff Russell1, Angie Roe2and James Eyres2, Department of Agriculture1, and Farm Focus Consultants, Northam2
22. Disease resistance update for wheat varieties in WA, Manisha Shankar, John Majewski, Donna Foster, Hossein Golzar, Jamie Piotrowski, Nicole Harry and Rob Loughman, Department of Agriculture
23. Effect of time of stripe rust inoculum arrival on variety response in wheat, Manisha Shankar, John Majewski and Rob Loughman, Department of Agriculture
24. Fungicide seed dressing management of loose smut in Baudin barley, Geoff Thomas and Kith Jayasena, Department of Agriculture
PESTS
25. How to avoid insect contamination in cereal grain at harvest, Svetlana Micic, Paul Matson and Tony Dore, Department of Agriculture
ABIOTIC
26. Environment â is it as important as variety in sprouting tolerance? Thomas (Ben) Biddulph1, Dr Daryl Mares1, Dr Julie Plummer1 and Dr Tim Setter2, School of Plant Biology, University of Western Australia1 and Department of Agriculture2
27. Frost or fiction, Garren Knell, Steve Curtin and Wade Longmuir, ConsultAg Pty Ltd, WA
28. High moisture wheat harvesting in Esperance 2005, Nigel Metz, South East Premium Wheat Growers Association (SEPWA) Projects Coordinator, Esperance, WA
SOILS
28. Hardpan penetration ability of wheat roots, Tina Botwright Acuña and Len Wade, School of Plant Biology, University of Western Australia
MARKETS
29. Crop shaping to meet predicted market demands for wheat in the 21st Century, Cindy Mills and Peter Stone,Australian Wheat Board, Melbourn
Changing perspectives on the internationalization of R&D and innovation by multinational enterprises: a review of the literature
Internationalization of R&D and innovation by Multinational Enterprises (MNEs) has undergone a gradual and comprehensive change in perspective over the past 50 years. From sporadic works in the late 1950s and in the 1960s, it became a systematically analysed topic in the 1970s, starting with pioneering reports and âfoundation textsâ. Our review unfolds the theoretical and empirical evolution of the literature from dyadic interpretations of centralization versus decentralization of R&D by MNEs to more comprehensive frameworks, wherein established MNEs from Advanced Economies still play a pivotal role, but new players and places also emerge in the global generation and diffusion of knowledge. Hence views of R&D internationalization increasingly rely on concepts, ideas and methods from IB and other related disciplines such as industrial organization, international economics and economic geography. Two main findings are highlighted. First, scholarly research pays an increasing attention to the network-like characteristics of international R&D activities. Second, different streams of literature have emphasized the role of location- specific factors in R&D internationalization. The increasing emphasis on these aspects has created new research opportunities in some key areas, including inter alia: cross-border knowledge sourcing strategies, changes in the geography of R&D and innovation, and the international fragmentation of production and R&D activities
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