Infection of T. subterraneum root hairs by Rhizobium trifolii was studied at root temperatures of 19°C or 7°C, and at 19°C after 9 days at 7°C. At 19°C infection began on 3-day-old plants but at 7°C was delayed till day 13 and occurred... more
Infection of T. subterraneum root hairs by Rhizobium trifolii was studied at root temperatures of 19°C or 7°C, and at 19°C after 9 days at 7°C. At 19°C infection began on 3-day-old plants but at 7°C was delayed till day 13 and occurred further from the hypocotyl. The initial infection was also slower at 7°C than at 19°C. After nodulation, the infection rate soon slowed at 19°C but not at 7°C. At 19°C, 3 days elapsed between first infection and first nodule formation but only 1 day with plants grown at 7°C or transferred to 19°C after 9 days at 7°C.-R.B. RESP-636
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Research Interests: Environmental Science, Soil Science, Agronomy, Biology, Tropics, and 4 moreRhizobium, Cultivar, Vertisol, and Soil Water
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Biosphere reserves operating under the UNESCO Man and the Biosphere Programme aim to achieve three mandate management objectives of conservation, sustainable socio-economic development, and logistic support. The apparent mismatch between... more
Biosphere reserves operating under the UNESCO Man and the Biosphere Programme aim to achieve three mandate management objectives of conservation, sustainable socio-economic development, and logistic support. The apparent mismatch between the biosphere reserve (BR) concept and implementation reality has led to the call for assessment of management effectiveness as part of a system to support management of sites under the Seville Statutory Framework for the Biosphere Reserves Network since 1995. We used the Enhancing our Heritage Toolkit developed by the International Union for Conservation of Nature (IUCN) and UNESCO to evaluate the management effectiveness of the Kien Giang Biosphere Reserve (KGBR). A lack of broad understanding for the conceptual model leads to the biosphere reserve concept being essentially an artificially constructed model with little buy-in from agencies of government and limited efforts to pursue an adequate planning and implementation process. The management s...
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Abstract Spray and freeze drying practices for production of the probiotic Bacillus amyloliquefaciens H57 as a power for feed applications were investigated. The importance of inlet temperature, feed rate, solid content, and limestone, a... more
Abstract Spray and freeze drying practices for production of the probiotic Bacillus amyloliquefaciens H57 as a power for feed applications were investigated. The importance of inlet temperature, feed rate, solid content, and limestone, a heating protectant, concentration was demonstrated. Spray drying outlet temperature appeared to be crucial for survivability of B. amyloliquefaciens H57. Studying inactivation kinetics at 80, 90, and 100 °C revealed the highest D-value at 260.7 ± 47.3 min at 80 °C before gradually declining with increasing temperature. By considering the D-value, a high survival rate of 100%, which was far superior to freeze drying at 60 ± 4%, was obtained when the spray drying outlet temperature was maintained at 80 °C with 175 ± 2 °C inlet temperature, 20.9 ± 0.4 mL min−1 feed rate, 20% solid content, and 1:0.3 ratio of dry mass of the probiotic material to limestone. After 50-days of storage, significant differences in the viability of B. amyloliquefaciens H57 were observed between the powders obtained by the two drying methods. Storage temperature had a substantial impact on the probiotic stability. Best viability retention was spray dried powder stored at 4 °C. This work demonstrates that spray drying can be an effective method for producing a functional probiotic and highlights its potential for applications in feed supplement manufacturing.
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The way biosphere reserve principles are applied in Vietnam was assessed through analysis of legal documents and an online survey with 41 managers and staff members of the Biosphere Reserve Management Boards and National Man and the... more
The way biosphere reserve principles are applied in Vietnam was assessed through analysis of legal documents and an online survey with 41 managers and staff members of the Biosphere Reserve Management Boards and National Man and the Biosphere Committee. The significant growth of the biosphere reserve network in Vietnam since 2000 is indicative of strong support from the National MAB Committee and the local provincial authorities in particular. Although all biosphere reserves conform to the Biosphere Reserve conceptual model, the operation and management effectiveness of sites is hindered by the predominant practice of sectoral and top-down control that is at odds with the intent of biosphere reserve management. The relatively weak legal status of biosphere reserves within the national framework is counter balanced by their more direct management by, and support from the autonomous provincial and city authorities. Recent administrative decentralisation in Vietnam allows the local authority flexibility in interpreting the central policies and regulations so as to benefit biosphere reserve management. Future sustainability and effectiveness of the biosphere reserves will depend on the implementation of appropriate, locally-based management solutions. This will require stronger support and commitment of the provincial leaders, relevant sectoral actors and communities to ensure cross-sectoral participation and collaboration, and secure adequate resourcing of biosphere reserve management activities
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The potential application of the spore-forming probiotic Bacillus amyloliquefaciens strain H57 (H57) as a novel probiotic for ruminants was evaluated in reproducing ewes. Performance responses were determined by delivering H57 in a... more
The potential application of the spore-forming probiotic Bacillus amyloliquefaciens strain H57 (H57) as a novel probiotic for ruminants was evaluated in reproducing ewes. Performance responses were determined by delivering H57 in a pelleted diet based mainly on palm kernel meal (PKM) and sorghum grain. PKM is an agro-industrial by-product with a reputation for poor palatability and the availability of the starch in sorghum grain can be limited in ruminants. The hypothesis was that H57 improves the feeding value of a relatively low quality concentrate diet. Twenty-four first-parity white Dorper ewes were fed PKM-based pellets manufactured with or without H57 (109 cfu/kg pellet) in late pregnancy. During this phase of late pregnancy, the H57 ewes ate 17% more dry matter (1019 vs 874 g/day, P = 0.03), gained more weight (194 vs 30 g/day, P = 0.008) and retained more nitrogen (6.13 vs 3.34 g/day, P = 0.01), but produced lambs with a similar birthweight (4.1 vs 4.2 kg, P = 0.73). Rumen f...
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O objetivo deste trabalho foi avaliar o efeito da aplicação do lodo de esgoto ao solo, na nodulação e fixação de N2, por estirpes nativas de rizóbio em associação com o feijoeiro, em experimento de casa de vegetação. Os tratamentos... more
O objetivo deste trabalho foi avaliar o efeito da aplicação do lodo de esgoto ao solo, na nodulação e fixação de N2, por estirpes nativas de rizóbio em associação com o feijoeiro, em experimento de casa de vegetação. Os tratamentos constituíram-se de: ausência de adubos químicos e de lodo; adubação química completa; doses equivalentes a 14,8 t ha-1, 29,6 t ha-1 e 59,2 t ha-1 de lodo; e feijão inoculado com estirpes de rizóbio + adubação nitrogenada no plantio. Os maiores valores da atividade de redução do acetileno e dos números e massas dos nódulos secos, nos tratamentos com as doses 14,8 t ha-1 e 29,6 t ha-1 de lodo, demonstram que a sua aplicação pode aumentar a eficiência simbiótica dos rizóbios nativos, em feijoeiro.
Research Interests: Physics and Horticulture
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Contiene: I. Mangrove management in Vietnam: The National Framework. -- II. Mangrove management in practice. -- III. Conclusion.
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There are now numbers of innovative water projects in Australia, already implemented and planned, that serve as a testing ground for new technologies, management approaches and institutional frameworks, generating valuable experience and... more
There are now numbers of innovative water projects in Australia, already implemented and planned, that serve as a testing ground for new technologies, management approaches and institutional frameworks, generating valuable experience and insights. To date, this knowledge is largely shared in an opportunistic, uncoordinated fashion. As a result, planners and practitioners alike often find it difficult to gain access to information about existing innovative water schemes and projects that could benefit the development of their own project. The Naiad project aims to change this by developing a computer program for sharing lessons learned from urban water schemes among planners, local governments, and practitioners. The project is a component of the Sustainable Water Sources program of the CRC for Water Quality and Treatment, which is carried out at The University of Queensland in collaboration with CSIRO. A preliminary version of Naiad has recently been completed. The current project s...
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This study examined whether the probiotic Bacillus amyloliquefaciens strain H57 (H57) affects ruminal fermentation parameters that exercise post-ingestive feedback appetite control mechanisms. A 4 × 4 Latin square design was used to... more
This study examined whether the probiotic Bacillus amyloliquefaciens strain H57 (H57) affects ruminal fermentation parameters that exercise post-ingestive feedback appetite control mechanisms. A 4 × 4 Latin square design was used to separate pre- and post-ingestive effects of H57 in four rumen-fistulated steers. The steers were offered a set amount of feedlot pellets, inoculated with H57 or without H57 (control, C). Half of the total amount of pellets fed were introduced intra-ruminally (r), and then the remaining pellets were orally consumed (o) to make four feeding treatments: H57r/H57o, H57r/Co, Cr/H57o and Cr/Co. Rumen fluid was sampled at 2, 4 and 6 h after feeding. Preference behaviour was tested immediately after the 6 h rumen fluid sampling by simultaneously offering the steers 4 kg of each of H57 and C pellets in adjacent troughs for 5 min. Steers preferred the pellets with added H57 over the C pellets (56:44; p < 0.001) and their preferences were not affected by the tre...
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Probiotic supplements are single or mixed strain cultures of live microorganisms that benefit the host by improving the properties of the indigenous microflora (Seo et al 2010). In a pilot study at the University of Queensland, Norton et... more
Probiotic supplements are single or mixed strain cultures of live microorganisms that benefit the host by improving the properties of the indigenous microflora (Seo et al 2010). In a pilot study at the University of Queensland, Norton et al (2008) found that Bacillus amyloliquefaciens Strain H57 (H57), primarily investigated as an inoculum to make high-quality hay, improved feed intake and nitrogen utilisation over several weeks in pregnant ewes. The purpose of the following study was to further challenge the potential of H57 -to show it survives the steam-pelleting process, and that it improves the performance of ewes fed pellets based on an agro-industrial by-product with a reputation for poor palatability, palm kernel meal (PKM), (McNeill 2013). Thirty-two first-parity White Dorper ewes (day 37 of pregnancy, mean liveweight = 47.3 kg, mean age = 15 months) were inducted into individual pens in the animal house at the University of Queensland, Gatton. They were adjusted onto PKM-b...
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The 2002-2003 drought, continued strong population growth in urban centres, and record low water storage levels have made sustainable water management a national priority. A paradigm shift toward water recycling and source substitution... more
The 2002-2003 drought, continued strong population growth in urban centres, and record low water storage levels have made sustainable water management a national priority. A paradigm shift toward water recycling and source substitution has led planners and practitioners to look for alternative solutions. Consequently, the Australian water sector is rapidly developing into a large community of practice (CoP), where sharing information and lessons learned is a key driver of innovation.
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Land disposal is commonly used for urban and industrial wastewater, largely due to the high costs involved in alternative treatments or disposal systems. However, the viability of such systems depends on many factors, including the... more
Land disposal is commonly used for urban and industrial wastewater, largely due to the high costs involved in alternative treatments or disposal systems. However, the viability of such systems depends on many factors, including the composition of the effluent water, soil type, the plant species grown, growth rate, and planting density. The objective of this study is to establish whether land disposal of nitrogen (N) rich effluent using an agroforestry system is sustainable, and determine the effect of irrigation rate and tree planting density on the N cycle and subsequent N removal. We examined systems for the sustainable disposal of a high strength industrial effluent. The challenge was to leach the salt, by using a sufficiently high rate of irrigation, while simultaneously ensuring that N did not leach from the soil profile. We describe the N balance for two plant systems irrigated with effluent, one comprising Eucalyptus tereticornis and Eucalyptus moluccana and a Rhodes grass (C...
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Mould and bacterial contamination releases microbial volatile organic compounds (mVOCs), causing changes in the odour profile of a feed. Bacillus amyloliquefaciens strain H57 (H57) has the potential ability to inhibit microbial growth in... more
Mould and bacterial contamination releases microbial volatile organic compounds (mVOCs), causing changes in the odour profile of a feed. Bacillus amyloliquefaciens strain H57 (H57) has the potential ability to inhibit microbial growth in animal feeds. This study tested the hypothesis that H57 influences the odour profile of stored feedlot pellets by impeding the production of mVOCs. The emission of volatile organic compounds (VOCs) of un-inoculated pellets and those inoculated with H57, stored either at ambient temperature (mean 22 °C) or at 5 °C, was monitored at 0, 1, 2, and 3 months by gas chromatography–mass spectrometry. Forty VOCs were identified in all the pellet samples analysed, 24 of which were potentially of microbial and 16 of non-microbial origin. A score plot of the principal component analysis (PCA) showed that the VOC profiles of the pellets stored at ambient temperature changed more rapidly over the 3 months than those stored at 5 °C, and that change was greater in ...
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This study tested the hypothesis that Bacillus amyloliquefaciens strain H57 (H57) improves preference by reducing the development of microbial volatile organic compounds (mVOCs) in feed pellets. Sixteen bull calves were, for 4 weeks,... more
This study tested the hypothesis that Bacillus amyloliquefaciens strain H57 (H57) improves preference by reducing the development of microbial volatile organic compounds (mVOCs) in feed pellets. Sixteen bull calves were, for 4 weeks, provided equal access to a panel of 8 automated feed bunks in a single paddock with some hay. Each bunk contained pellets with (H57) or without (Control) the H57, each aged for 4 months at either ambient or chiller temperature. Each treatment was changed to a new bunk pair position weekly. Relative preference was determined according to weight of pellets remaining per hour per treatment bunk pair per 24 h. Pellets were analysed for volatile organic compounds (VOCs) and the concentrations tested for correlation with relative preference. Calves showed the lowest preference (p < 0.0001) for the Control/Ambient treatment whereas preference for all other treatments (H57/Ambient; H57/Chiller; Control/Chiller) was similar. The Control/Ambient treatment odou...
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The probiotic Bacillus amyloliquefaciens H57 increased weight gain, increased nitrogen retention and increased feed intake in ruminants when administered to the diet. This study aims to develop a better understanding of this probiotic... more
The probiotic Bacillus amyloliquefaciens H57 increased weight gain, increased nitrogen retention and increased feed intake in ruminants when administered to the diet. This study aims to develop a better understanding of this probiotic effect by analysing changes in the rumen prokaryotic community. Sequencing the 16S rRNA gene PCR amplicons of the rumen microbiome, revealed that ewes fed H57 had a significantly different rumen microbial community structure to Control sheep. By contrast, dairy calves showed no significant differences in rumen community structure between treatment groups. In both instances, H57 was below detection in the rumen community profile and only present at low relative abundance as determined by qPCR. The altered rumen microbial community in sheep likely contributes to increased weight gain through more efficient digestion of plant material. As no change occurred in the rumen community of dairy calves it is suggested that increased weight gain may be due to cha...
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The technique of delayed inoculation with effective, ineffective, or mixtures of effective + ineffective nodule bacteria was used to study seedling symbiosis of barrel medic, M. tribuloides, in sand culture.
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Chemical data regarding the protein content and quality of the tuberous roots of four grain legumes suited to cultivation in the humid tropical lowlands are presentend. Crude protein was estimated as a product of % nitrogen in the meals... more
Chemical data regarding the protein content and quality of the tuberous roots of four grain legumes suited to cultivation in the humid tropical lowlands are presentend. Crude protein was estimated as a product of % nitrogen in the meals extracted with 70% (v/v) ethanol x 6.25 and the amino acid composition of the proteins was estimated by analysis of meals
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Biosphere reserves established under the UNESCO Man and the Biosphere Program aim to harmonise biodiversity conservation and sustainable development. Concerns over the extent to which the reserve network was living up to this ideal led to... more
Biosphere reserves established under the UNESCO Man and the Biosphere Program aim to harmonise biodiversity conservation and sustainable development. Concerns over the extent to which the reserve network was living up to this ideal led to the development of a new strategy in 1995 (the Seville Strategy) to enhance the operation of the network of reserves. An evaluation of effectiveness of management of the biosphere reserve network was called for as part of this strategy. Expert opinion was assembled through a Delphi Process to identify successful and less successful reserves and investigate common factors influencing success or failure. Ninety biosphere reserves including sixty successful and thirty less successful reserves in 42 countries across all five Man and the Biosphere Program regions were identified. Most successful sites are the post-Seville generation while the majority of unsuccessful sites are pre-Seville that are managed as national parks and have not been amended to c...
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A spore-forming probiotic, Bacillus amyloliquefaciens strain H57 (H57), was administered to dairy calves in starter pellets to determine effects on liveweight gain, feed conversion efficiency and animal health under summer feeding... more
A spore-forming probiotic, Bacillus amyloliquefaciens strain H57 (H57), was administered to dairy calves in starter pellets to determine effects on liveweight gain, feed conversion efficiency and animal health under summer feeding conditions, without antibiotics. Twenty-four male and female calves were allocated into two groups and from 4 weeks of age individually offered 6 L/day of whole milk and ad libitum starter pellets impregnated with H57 (3.16 × 108 cfu per kg DM) or without (Control) until 12 weeks of age. The calves were housed in a non-air-conditioned animal house, with deep-straw bedding over concrete, under typically challenging subtropical summer conditions. After 12 weeks the calves were released into a grazing paddock as one group and were supplemented ad libitum with control pellets and hay, until 19 weeks of age. From Weeks 4 to 12, liveweight and feed intakes were measured weekly and health status was monitored daily. Rumen fluid and blood were collected at Weeks 4...
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Nitrogen fixation in the rhizosphere of Paspalum notatum, variety “Batatais”, associated with Azotobacter paspali and sugar cane associated with Beijerinckia sp., both grown in the field, was studied by the acetylene reduction method. In... more
Nitrogen fixation in the rhizosphere of Paspalum notatum, variety “Batatais”, associated with Azotobacter paspali and sugar cane associated with Beijerinckia sp., both grown in the field, was studied by the acetylene reduction method. In the association P. notatum - A. paspali values equivalent to a Nitrogen fixation of 15 to 93 kg/ha/year were obtained (ratio C 2 H 2 :N 2 = 3:1). Almost all of the nitrogenase activity was concentrated on the root surface and very little was found in rhizosphere soil. Nitrogenase activity of both systems was very sensitive to oxygen. On roots separated from soil a pO 2 of 0.04 atm was optimal while in the intact systems the oxygen tension above the soil had little effect. Nitrogenase activity in the rhizosphere of P. notatum seemed directly dependent upon photosynthetic activity of the plant. Normal 8 hour night periods did not change nitrogenase activity but when the dark period was extended the activity slowed down. On returning the plants into light, within hours the original activity was reached.
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Mangroves have been systematically exploited in Indonesia since 1800, especially for the development of brackish water shrimp aquaculture (called ‘tambak’) and for timber harvesting. By the end of the 1960s, Indonesia is estimated to have... more
Mangroves have been systematically exploited in Indonesia since 1800, especially for the development of brackish water shrimp aquaculture (called ‘tambak’) and for timber harvesting. By the end of the 1960s, Indonesia is estimated to have lost more than 200,000 ha of its mangroves mostly in Java and Sumatra. The rate of mangrove loss started to dramatically increase in the 1970 when exploitation shifted to new areas outside Java, particularly in Kalimantan and Sulawesi, encouraged by government policies to boost timber production, followed by policies to expand tambak in 1980s and large scale tambak development triggered by increased shrimp price during Asian financial crisis in 1997. The result has been the loss of nearly 800,000 ha of mangroves in only 30 years, mostly now in the form of low productivity or abandoned tambaks. In recent years, timber harvesting activities in Indonesia's mangroves appear to have become more sustainable. Our analysis suggests that aquaculture will continue as the main driver of change in mangrove ecosystems in Indonesia followed by palm oil plantation. Failure to deal with the current low productivity of shrimp aquaculture in many parts of Indonesia will force shrimp producers to clear an estimated 600,000 ha more mangroves to make way for shrimp farms over the next two decades. However, with improvements in brackish water aquaculture productivity, halting palm oil concession to utilise mangroves, along with maintaining other mangrove use pressures at moderate levels, the net loss of mangroves in the next two decades could be reduced to around 23,000 ha.
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[Extract] The Philippines with a large population and low per-capita income faces severe pressure on its residual forest resources and has a recent history of rapid deforestation. Various policy initiatives have been introduced topromote... more
[Extract] The Philippines with a large population and low per-capita income faces severe pressure on its residual forest resources and has a recent history of rapid deforestation. Various policy initiatives have been introduced topromote reforestation, with low levels of success. Timber marketing and milling was a major component of the Philippine economy until recently when changes in government policy reduced the volume of logging in native forests. Because of this shortage, the use of coco lumber has expanded. This chapter discusses forest industries and stakeholders in the Philippines, and in particular farm, social and community forestry systems. There are a number of impediments to all forms of reforestation. Government policy has moved from mainly supporting industrial and large-scale planting schemes to also promoting community forestry.