82 research outputs found

    Relationships of frequencies of extreme low temperatures with grain yield of some Australian commercial chickpea cultivars

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    In this study, we examined the relationships between extremes of low temperatures and chickpea yield in 12 field experiments conducted at six sites in the subtropical environment of southeast Queensland (SEQ) from 2014 to 2019. Three commercial chickpea cultivars, PBA-Boundary, PBA-HatTrick and PBA-Seamer, were grown in all the experiments. Cultivars PBA-Pistol, PBA-Monarch and Kyabra were also included in three of these experiments conducted in 2015. In these experiments, the crop experienced a total of 8 to 41 frosts (minimum temperature <  = 0 °C), 2 to 41 pre-flowering frosts, 2 to 19 frosts during the critical period, 0 to 13 frosts and 2 to 71 low-temperature days (< = 15 °C) after flowering. The mean yield, which varied from 1 to 3 t/ha, was negatively related to post-flowering frosts (r =  − 0.74, p < 0.01) and low-temperature days (r =  − 0.76, p < 0.01), and positively related to pre-flowering frosts (r = 0.67, p < 0.05). Each post-flowering frost was associated with a 5% decrease and a low-temperature day with a 1% decrease in yield. The cultivar × site interaction was significant only in the three experiments with six commercial cultivars. This interaction was most likely due to an increase in the sensitivity range with additional cultivars, as indicated by frost damage scores and their relationships with yield. The results imply that extreme low-temperature events after flowering could negatively impact chickpea yield in SEQ and similar subtropical environments. Overcoming these effects through management and breeding should increase and stabilise chickpea yield

    Formal planning and the reshaping of public sector professional work

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    This paper deals with the ‘managerialization’ of public sector professional work. Specifically, it will focus on the role of formal planning practices (as expressed in strategic planning, project management and budgeting practices) in changing public sector professional work. Planning and accounting are at the heart of public sector reforms, responding to a logic of having public service professionals transparent on what they do, on how they pursue their goals, and accountable on the use of resources and on results. Thus planning and accounting practices have been transferred from private sector management models to public, professional organizations. Yet public sector professional organizations can be conceived as a pluralistic setting characterized by diffuse power, fragmented objectives and knowledgebased and are deeply embedded in public administration regulatory logics: how can management models deriving from private, hierarchical firms be applied to the specificities and complexities of public, pluralistic settings? What is the specific meaning of formal planning practices in such complex contexts? Based on a qualitative, single case study design, this paper will show how the planning system (in its manifestation of strategic planning, project management and budgeting) applied in a public hospital apparently ‘fails’ when its deliberate role of serving as a tool for decisions is considered. Yet it is widely in use and widely accepted by professionals as well. Conclusions on the value of formal planning when other emergent roles are taken into account will be discussed

    Mycotoxins and toxigenic fungi in sago starch from Papua New Guinea

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    Aims: to assay sago starch from Papua New Guinea (PNG) for important mycotoxins and to test fungal isolates from sago for mycotoxin production in culture.\ud \ud Methods and Results: sago starch collected from Western and East Sepik Provinces was assayed for aflatoxins, ochratoxin A, cyclopiazonic acid, sterigmatocystin, citrinin and zearalenone and all 51 samples were negative. Frequently\ud isolated species of Penicillium (13), Aspergillus (five) and Fusarium (one) were cultured on wheat grain, and tested for the production of ochratoxin A, cyclopiazonic acid, sterigmatocystin, citrinin, patulin and penicillic acid. All 12 isolates of P. citrinin and one of two A. flavipes isolates produced citrinin. A single isolate of A. versicolor produced sterigmatocystin. No other mycotoxins\ud were detected in these cultures.\ud \ud Conclusions: no evidence was found of systemic mycotoxin contamination of sago starch. However, the isolation of several mycotoxigenic fungi shows the potential for citrinin and other mycotoxins to be produced in sago stored\ud under special conditions.\ud \ud Significance and Impact of the study: sago starch is the staple carbohydrate in lowland PNG and the absence of mycotoxins in freshly prepared sago starch is a positive finding. However, the frequent isolation of citrinin-producing fungi indicates a potential health risk for sago consumers, and food safety is dependant on promoting good storage practices

    Physiological mechanisms underpinning tolerance to high temperature stress during reproductive phase in mungbean (Vigna radiata (L.) Wilczek)

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    This study investigated the physiological factors underlying genotypic variation in response to high temperature and the role of acclimation prior to high temperature stress, in mungbean genotypes, selected based on their sensitivity to high temperature. The genotypes were subjected to three temperature regimes during the reproductive phase, i.e. normal (28 °C/24 °C, CON), acclimation temperature (35 °C/28 °C, Ac-HT) before transferring to high temperature (45 °C/30 °C), and direct exposure of non-acclimated plants to high temperature (45 °C/30 °C, NAc-HT). Environmentally controlled growth chambers were used to provide the required temperature regimes. The plants were maintained at fully watered conditions throughout the growing cycle. The average shoot biomass (including root) was reduced by 9% and 41%, and the grain yield by 31% and 50%, in the acclimated (Ac-HT) and non-acclimated (NAc-HT) treatments, respectively, compared to CON. The mean root weight in the NAc-HT treatment was reduced by 32%, while the mean root weight in Ac-HT treatment was comparable to CON, although there was genotypic variation with in the treatments. The mean root weight in the tolerant group was 48%, 180% and 130% greater than susceptible group, in CON, Ac-HT and NAc-HT treatments, respectively. There was significant variation among genotypes for root weight. A positive relationship (r = 0.54**) between root and shoot weight indicated that plants with larger root weight also produced higher shoot biomass. The high temperature tolerant genotypes responded to acclimation treatment by promoting root growth while such enhanced root growth was not observed in susceptible genotypes. The study suggested that acclimation treatment followed by high temperature could be used as a technique to identify genotypes with ability to adapt to high temperature stress conditions

    More efficient breeding of drought resistant groundnut in India and Australia

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    This article considers breeding programmes aimed at the production of drought resistant genotypes during the 1990s up to 2001. Cost benefit analyses were conducted to compare indirect selection methods with conventional yield selection approaches

    Where To from Here?

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    WATER IS GROWING in importance as a limiting factor in agriculture due to the unpredictable nature of rainfall and increasing competition for it from human and industrial uses. To sustain agricultural productivi- ty, water-use-efficient systems are required. Transpiration-efficient cultivars are an important component of such systems
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