Influence of Nitrogen and Sink Competition on Shoot Growth of Poplar

Terrestrial and oceanic biomass carbon sinks help reduce anthropogenic CO2 emissions and mitigate the long-term effect of increasing atmospheric CO2. Woody plants have large carbon pools because of their long residence time, however N availability can negatively impact tree responses to elevated CO2. Seasonal cycling of internal N in trees is a component that contributes to fitness especially in N limited environments. It involves resorption from senescing leaves of deciduous trees and storage as vegetative storage proteins (VSP) in perennial organs. Populus is a model organism for tree biology that efficiently recycles N. Bark storage proteins (BSP) are the most abundant VSP that serves as seasonal N reserves. Here I show how poplar growth is influenced by N availability and how growth is influenced by shoot competition for stored N reserves. I also provide data that indicates that auxin mediates BSP catabolism during renewed shoot growth. Understanding the components of N accumulation, remobilization and utilization can provide insights leading to increasing N use efficiency (NUE) of perennial plants.

Competition of sorghum cultivars and densities with Japanese millet (Echinochloa esculenta).

Field studies were conducted at two locations in southern Queensland, Australia during the 2003-2004 and 2004-2005 growing seasons to determine the differential competitiveness of sorghum (Sorghum bicolor L. Moench) cultivars and crop densities against weeds and the sorghum yield loss due to weeds. Weed competition was investigated by growing sorghum in the presence or absence of a model grass weed, Japanese millet (Echinochloa esculenta). The correlation analyses showed that the early growth traits (height, shoot biomass, and daily growth rate of the shoot biomass) of sorghum adversely affected the height, biomass, and seed production of millet, as measured at maturity. "MR Goldrush" and "Bonus MR" were the most competitive cultivars, resulting in reduced weed biomass, weed density, and weed seed production. The density of sorghum also had a significant effect on the crop's ability to compete with millet. When compared to the density of 4.5 plants per m2, sorghum that was planted at 7.5 plants per m2 suppressed the density, biomass, and seed production of millet by 22%, 27% and 38%, respectively. Millet caused a significant yield loss in comparison with the weed-free plots. The combined weed-suppressive effects of the competitive cultivars, such as MR Goldrush, and high crop densities minimized the yield losses from the weeds. These results indicate that sorghum competition against grass weeds can be improved by choosing competitive cultivars and by using a high crop density of > 7.5 plants per m2. These non-chemical options should be included in an integrated weed management program for better weed management, particularly where the control options are limited by the evolution of herbicide resistance.

Competition between Stipa grandis and Cleistogenes squarrosa

Competitive strategy for resources between Cleistogenes squarrosa (Trin.) Keng which is a dominant species of grasslands degraded by moderate-heavy grazing, and Stipa grandis P. Smirnov, which is a dominant species of ungrazed communities, was studied using a replacement series method in a greenhouse. The knowledge would be helpful in managing grasslands and restoring the degraded C. squarrosa grassland. Although there was neither inter- nor intra-specific competition between the two species when no nutrients were added, intra-specific competition of C. squarrosa was observed and increased with increased nutrient availability and more sulfur (S) was allocated to the aboveground partition of the plant. Relative competitive ability of C. squarrosa was greater than that of S. grandis when nutrients were supplied regardless of S. There was no significant difference between shoot and root competition based on dry matter yields. However, root competition was significantly greater than that of shoot based on S uptake under all treatments. A significant interaction was not observed between shoot and root competition. Therefore, nutrients addition benefits the restoration of degraded grassland of C. squarrosa, which may not exclude S. grandis. Also productivity and forage quality of the community will be increased. (C) 2007 Elsevier Ltd. All rights reserved.

Combining competition from Lolium perenne and an insect-fungus combination to control Rumex obtusifolius seedlings

Although adult Rumex obtusifolius are problematic weeds, their seedlings are poor competitors against Lolium perenne, particularly in established swards. We investigated the possibility of using this weakness to augment control of R. obtusifolius seedlings with combinations of Gastrophysa viridula (Coleoptera: Chrysomelidae) and the rust fungus Uromyces rumicis. Rumex obtusifolius seedlings were grown in competition with L. perenne sown at different rates and times after R. obtusifolius: they competed successfully with L. perenne when sown 21 days before the grass. Sowing both species at the same time resulted in a dominant grass sward, with R. obtusifolius becoming dominant when sown 42 days prior to L. perenne. Grass sowing rate had no effect on R. obtusifolius growth or biomass. A second experiment investigated how competition from L. perenne sown 21 days after R. obtusifolius combined with damage from G. viridula and/or U. rumicis (applied at either the 3-4- or 10-13-leaf stage, or at both stages) affected the growth and final biomass of R. obtusifolius. Beetle grazing at the latter leaf stage was the only treatment that reduced R. obtusifolius biomass, although rust infection at the earlier application led to an increase in shoot and root weight. The results are discussed in terms of the potential for use of these agents in the field.

The Get Marketer Challenge Innovation: Challenging students using a tournament style competition

This paper presents an assessment innovation which used a tournament style competition to challenge and engage first year marketing students. The course-wide competition required student teams to solve real-world marketing problems for industry sponsors. Student feedback reflects enjoyment of the task and the competition, with students welcoming the opportunity to put theory into practice. Student attendance in the lectures and tutorials involving team presentations was improved. This structure can be adapted for any course with large enrolments. We recommend that instructors adopting a tournament structure consider grading mechanisms that promote equal effort and additional rewards, such as bonus marks, for teams progressing in subsequent rounds.

Synopolies: The use of cryptographic technologies to impede competition in multiple jurisdictions

Many jurisdictions have developed mature infrastructures, both administratively and legislatively, to promote competition. Substantial funds have been expended to monitor activities that are anticompetitive and many jurisdictions also have adopted a form of "Cartel Leniency Program", first developed by the US Federal Trade Commission, to assist in cartel detection. Further, some jurisdictions are now criminalizing cartel behaviour so that cartel participants can be held criminally liable with substantial custodial penalties imposed. Notwithstanding these multijurisdictional approaches, a new form of possibly anticompetitive behaviour is looming. Synergistic monopolies („synopolies‟) involve not competitors within a horizontal market but complimentors within separate vertical markets. Where two complimentary corporations are monopolists in their own market they can, through various technologies, assist each other to expand their respective monopolies thus creating a barrier to new entrants and/or blocking existing participants from further participation in that market. The nature of the technologies involved means that it is easy for this potentially anti-competitive activity to enter and affect the global marketplace. Competition regulators need to be aware of this potential for abuse and ensure that their respective competition frameworks appropriately address this activity. This paper discusses how new technologies can be used to create a synopoly.

Competition laws and policies in China and Hong Kong : a tale of two regulatory journeys

Reviews the background to China's enactment of the Anti-Monopoly Law in 2007 and compares the debate surrounding the proposed introduction of similar legislation in Hong Kong. Examines the main issues arising during the Law's 13 year drafting stage, its key provisions and the remaining areas of uncertainty concerning its enforcement. Discusses ongoing efforts to introduce competition law regulations in Hong Kong, the main features of the draft General Competition Law and the shortcomings of its approach to penalties and exemptions.

The economics of credence goods: An experimental investigation of the role of verifiability, liability, competition and reputation in credence goods markets

Credence goods markets are characterized by asymmetric information between sellers and consumers that may give rise to inefficiencies, such as under- and overtreatment or market break-down. We study in a large experiment with 936 participants the determinants for efficiency in credence goods markets. While theory predicts that either liability or verifiability yields efficiency, we find that liability has a crucial, but verifiability only a minor effect. Allowing sellers to build up reputation has little influence, as predicted. Seller competition drives down prices and yields maximal trade, but does not lead to higher efficiency as long as liability is violated.

Post-WTO China : competition and technology transfer laws in the 'new' socialist market economy

China has been the focus of much academic and business scrutiny of late. Its economic climate is changing and its huge new market opportunities seem quite tantalizing to the would-be 'technology entrepreneur'. But China's market is a relatively immature one; it is still in the process of being opened up to real competition. The corollary of this is that, at this stage of the transitional process, there is still significant State control of market function. This article discusses Chinese competition law, the technology transfer system, how the laws are being reformed and how the technology entrepreneur fares under them. The bottom line is that while opportunities beckon, the wise entrepreneur will nevertheless continue to exercise caution.

The nine lives of Vietnam's new competition law

Vietnam's present draft of the proposed new Law on Competition is currently in its ninth version. Although there is a need to enact legislation as quickly as possible, Vietnam cannot rush the drafting process. Under its Bilateral Trade Agreement with the USA, Vietnam has committed to improve the quality of its laws and consistency of its legislative framework. Since the Law on Competition will be fundamental in establishing the legal framework for a more coherent and effective competition regime, and will have profound influences on Vietnam's objective of becoming a socialist-oriented market economy, its provisions must be well constructed and well considered, and this takes time. This article shows how the proposed Law is being crafted as compared to older drafts which sheds light on changes in policy during the drafting process. Where possible, the Draft is also compared with the laws in other jurisdictions for any assistance they might lend. In this author's opinion not all the changes are positive but any defects in the draft are not intractable and can be remedied prior to promulgation.