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Exploring the Challenges and Opportunities of Mango Export from Indonesia: Insights from Stakeholder Interviews
Get PDFDespite being one of the world’s primary producers, Indonesia faces challenges in increasing mango exports. The government has been promoting mango exports to boost economic growth in the agricultural sector. The purpose of this study is to identify opportunities and challenges that are associated with increasing mango exports from Indonesia. We conducted a qualitative assessment through in-depth interviews with 20 Indonesian mango exporters and government officials, to identify opportunities and challenges associated with increasing mango exports from Indonesia. Our findings reveal that the physical qualities demanded by export markets do not significantly differ from those required by modern domestic markets. We also found that despite global mango markets typically favouring red and yellow mango, there is potential for Harumanis, a sweet green mango variety primarily grown in Indonesia, to be exported to East Asia and several Eastern European countries, which also do not require strict non-physical requirements for imported mangoes. However, the shortage of export-quality mangoes from the on-farm level hinders this effort, together with the lack of advanced postharvest and logistics management, and the absence of quality certification. We recommend to improving physical quality and meeting non-physical requirements, such as certification, at every level of the mango industry value chain
Poleroviruses in vegetable legumes
No full textVegetable and pulse legumes are very important sources of human and animal nutrition and are known to be susceptible to many plant viruses, including members of the genus Polerovirus. Thirteen species or tentative species have been reported from vegetable or pulse legume crops, of which turnip yellows virus and chickpea chlorotic stunt virus are particularly prevalent and important. This review summarizes and discusses information on Polerovirus biology, impact, epidemiology, and disease management and highlights a need for further studies of these legume pathogens
Fluorescently Tagged Verticillium dahliae to Understand the Infection Process on Cotton (Gossypium hirsutum) and Weed Plant Species
Get PDFVerticillium wilt is a soil-borne disease caused by distinct vegetative compatibility groups (VCG) of the fungus Verticillium dahliae. Defoliating (VCG 1A) and non-defoliating (VCG 2A) pathotypes of V. dahliae have contributed to yield losses of cotton production in Australia. To study the virulence and the infection process of V. dahliae on cotton, two isolates, one representing each VCG, have been transformed with fluorescent protein genes. The transformants maintained their ability to infect the host, and both strains were observed to move through the plant vasculature to induce wilt symptoms. Furthermore, virulence testing suggests that the cotton V. dahliae strains can endophytically colonise common weed plant species found in the Australian landscape, and that is contrasted by their ability to infect and colonise native tobacco plants. The fluorescently labelled strains of V. dahliae not only allowed us to gain a thorough understanding of the infection process but also provided a method to rapidly identify recovered isolates from host colonisation studies
Analysis of plant and fungal transcripts from resistant and susceptible phenotypes of Leptospermum scoparium challenged by Austropuccinia psidii
Get PDFAustropuccinia psidii is the causal pathogen of myrtle rust disease of Myrtaceae. To gain understanding of the initial infection process, gene expression in germinating Austropuccinia psidii urediniospores and in Leptospermum scoparium inoculated leaves were investigated via analyses of RNAseq samples taken 24 and 48 hours post inoculation (hpi). Principal component analyses of transformed transcript count data revealed differential gene expression between the uninoculated L. scoparium control plants that correlated with the three plant leaf resistance phenotypes (immunity, hypersensitive response and susceptibility). Gene expression in the immune resistant plants did not significantly change in response to fungal inoculation, while susceptible plants showed differential expression of genes in response to fungal challenge. A putative disease resistance gene, jg24539.t1, was identified in the L. scoparium hypersensitive response phenotype family. Expression of this gene may be associated with the phenotype and could be important for further understanding the plant hypersensitive response to A. psidii challenge. Differential expression of pathogen genes was found between samples taken 24 and 48 hpi, but there were no significant differences in pathogen gene expression that were associated with the three different plant leaf resistance phenotypes. There was a significant decrease in the abundance of fungal transcripts encoding three putative effectors and a putative carbohydrate-active enzyme between 24 and 48 hpi, suggesting that the encoded proteins are important during the initial phase of infection. These transcripts, or their translated proteins, may be potential targets to impede the early phases of fungal infection by this wide-host range obligate biotrophic basidiomycete
Geministatins: new depside antibiotics from the fungus Austroacremonium gemini
Get PDFTwo new depside antibiotics, geministatins A (1) and B (2), were isolated from the fungus Austroacremonium gemini MST-FP2131 (Sordariomycetes, Ascomycota), which was recovered from rotting wood in the wet tropics of northern Australia. The structures of the geministatins were elucidated by detailed spectroscopic analysis, chemical degradation and comparison with literature values. Chemical degradation of 1 and 2 yielded three new analogues, geministatins C–E (3–5), as well as a previously reported compound dehydromerulinic acid A (6). Compounds 1, 2 and 6 exhibited antibacterial activity against the Gram-positive bacteria Bacillus subtilis (MIC 0.2–1.6 µg mL−1) and Staphylococcus aureus (MIC 0.78–6.3 µg mL−1), including methicillin-resistant S. aureus (MRSA), while 4 exhibited antifungal activity against the yeast Saccharomyces cerevisiae (MIC 13 µg mL−1)
The use of cell and larval assays to identify target genes for RNA interference-meditated control of the Australian sheep blowfly (Lucilia cuprina)
Get PDFBACKGROUND Flystrike, primarily caused by Lucilia cuprina, is a major health and welfare issue for sheep wool industries. Current chemical-based controls can have limited effectiveness due to the emergence of resistance in the parasite. RNA interference (RNAi), which uses double-stranded RNA (dsRNA) as a trigger molecule, has been successfully investigated for the development of innovative pest control strategies. Although RNAi offers great potential, the efficient identification, selection of target genes and delivery of dsRNA represent challenges to be overcome for the successful application of RNAi for control of L. cuprina. RESULTS A primary L. cuprina (blowfly) embryo cell line (BFEC) was established and confirmed as being derived from L. cuprina eggs by PCR and amplicon sequencing. The BFECs were successfully transfected with plasmids and messenger RNA (mRNA) expressing fluorescent reporter proteins and dsRNA using lipid-based transfection reagents. The transfection of dsRNA into BEFC in this study suggested decreased mRNA levels of target gene expression, which suggested RNAi-mediated knockdown. Three of the dsRNAs identified in this study resulted in reductions of in target gene mRNA levels in BFEC and loss of biological fitness by L. cuprina larvae in a feeding bioassay. CONCLUSION This study confirms that the novel BFEC cell line can be used to improve the efficacy of dsRNA-mediated screening to accelerate the identification of potential target genes in the development of RNAi mediated control approaches for L. cuprina. The research models established in this study are encouraging with respect to the use of RNAi as a blowfly control method, however further improvement and validation are required for field applicationsnot prefect, and could be ongoing developing. © 2024 Society of Chemical Industry
Soybean and peanut rotations benefit sugarcane production in the Burdekin
No full textThe inclusion of complimentary rotational cash crops in the sugarcane production system offers an opportunity to improve soil health, productivity and profitability. This has been successfully demonstrated in the Bundaberg region. However, in the Burdekin region, there are concerns that growing a soybean or peanut crop in the traditional fallow period may adversely impact sugarcane productivity and profitability due to delays in planting the following sugarcane plant crop. To better understand the impact of soybean and peanut rotations on soil health, sugarcane productivity and gross margins in the Burdekin, a replicated and randomised strip trial comprising three different fallow management treatments (bare, soybeans, peanuts) was established in the Delta area after harvesting the final ratoon crop in 2019. Three nitrogen (N) rate treatments were then applied to the sugarcane plant crop in 2020 to the corresponding soybean (60, 115, 170 kg N/ha) and peanut (40, 105, 170 kg N/ha) treatment areas. Soybean and peanut rotations improved key soil health indicators and sugarcane root-system parameters compared to a bare fallow. The soybean and peanut rotations also contributed to higher gross margins, suggesting that soybean and peanut rotations could be a valuable addition to the sugarcane production system in the Burdekin region
Weed Biological Control Status and Options for Sri Lanka
No full textInvasive alien plants can cause significant losses in production and biodiversity, and due to the high costs of conventional control, biological control is often the only feasible long-term option for their management. Weed biological control was first attempted in Sri Lanka in 1865, with the introduction of Dactylopius ceylonicus to control prickly pear (Opuntia monacantha). Since then, 10 more biological control agents have been introduced into Sri Lanka to control an additional six weed species. Field surveys were conducted to record invasive weeds in Sri Lanka that had been targets for biological control in other countries to identify possible biological control options for Sri Lanka. Over 70 sites were surveyed, covering eight of the nine provinces. Nineteen weed species that are considered invasive and the target of biological control elsewhere were sighted. Biological control attempts have been initiated in Sri Lanka against six of these species: Chromolaena (Chromolaena odorata), water hyacinth (Pontederia crassipes), two types of prickly pear (Opuntia monacantha, and Opuntia stricta), parthenium weed (Parthenium hysterophorus) and salvinia (Salvinia molesta), with mixed success. Introduced biological control agents were not found in all areas where their target weed species were sighted. Therefore, the re-distribution of some of these agents, as well as the introduction of additional biological control agents for chromolaena, lantana (Lantana camara) and parthenium weed, could be reconsidered, given the priorities attached to these species. During the surveys, four biological control agents that had not been deliberately introduced into Sri Lanka were found on lantana, and one agent was found on Noogoora burr (Xanthium strumarium), presumably having spread from India. However, as lantana is not considered under adequate control, the importation of several other biological control agents that have been released worldwide could be investigated. There are good biological control prospects for numerous other weed species also, including alligatorweed (Alternanthera philoxeroides), Madeira vine (Anredera cordifolia), air yam (Dioscorea bulbifera), mile-a-minute (Mikania micrantha), two types of giant sensitive plants (Mimosa diplotricha and Mimosa pigra), parrot’s feather (Myriophyllum aquaticum) and water lettuce (Pistia stratiotes)
Applying acoustic telemetry, vessel tracking and fisher knowledge to investigate and manage fisher-shark conflict at Lord Howe Island, Australia
No full textFisher-shark conflict is occurring at Lord Howe Island, Australia due to high levels of Galapagos shark (Carcharhinus galapagensis) depredation (where sharks consume hooked fish) and bycatch. Depredation causes costly loss of target catch and fishing gear and increased mortality of target species, and sharks can be injured or killed when bycaught. This study applied acoustic telemetry and vessel tracking from 2018 to 2021 to identify; (1) how the movements of 30 tagged sharks and activity of six fishing vessels overlapped, and (2) where key ‘hotspots’ of overlap occurred. Fisher surveys were also conducted to collect information about mitigating shark interactions. Residency index analysis indicated that three sharks tagged at a fish waste dumping site had markedly higher residency. Core home ranges of sharks overlapped with higher fishing activity at four ‘hotspots’. Statistical modelling indicated positive linear effects of fishing activity and bathymetric complexity on shark detections and tagged sharks were present for 13% of the total time that vessels were fishing close to acoustic receivers. Spatio-temporal overlaps between shark movements and fishing activity could potentially have occurred because sharks learned to associate fishing vessels with food (i.e. hooked fish) and because fishers and sharks utilise highly productive shelf edge areas, however more research is needed to investigate these relationships. Fishers reported that rotating fishing areas and reducing time at each location, fishing deeper than 100 m, and using electric reels and lures instead of bait, reduced bycatch and depredation. The integrated approach used here identified practical methods for reducing fisher-shark conflict, improving socio-economic outcomes for fishers and conservation prospects for this unique shark population
Delivery of the Australian Weeds Strategy by the national Weeds Working Group (WWG)
No full textFederal, state and territory governments and other parties collaborate to deliver the goals and priorities of the Australian Weeds Strategy (AWS). The national Weeds Working Group (WWG) is the mechanism through which this collaboration occurs.
The WWG has 19 members representing every State and Territory of Australia, the Commonwealth government, research bodies, CSIRO and the Centre for Invasive Species Solutions (CISS).
WWG sits within a framework of higher level national committees including the Environment and Invasives Committee (EIC), and above them, the National Biosecurity Committee. WWG is a subgroup of the EIC and is charged with the responsibility to inform national policy leadership to the EIC in the priority areas of the AWS. WWG provides the EIC with technical and policy advice on the prevention, incursion response and management of invasive plants, under the framework of the AWS.
WWG members form task groups to work together on particular priorities of the AWS. Current tasks in the WWG workplan include: Australian Weeds Strategy implementation, National Established Weed Priorities (NEWP), collaboration with the ornamental plant industry on invasive garden plant prevention, improved availability of weed specimens in herbaria for identification and research purposes, prioritisation of biocontrol agents, oversight of relevant information on weeds.org.au, input to WeedScan, reporting process for new plant naturalisations, input to a national weed risk assessment portal, and input to the National Priority List of Exotic Environmental Pests, Weeds and Diseases (abbreviated to the Exotic Environmental Pest List (EEPL)).
The WWG usually meets twice a year and out-of-session as needed. Contributing at this national level is a great way to share and develop ideas and collectively progress weed issues nationally