BACKGROUNDThe mechanisms that regulate multi-annual population dynamics of rodent pest species of cereal crops is often unknown. Better knowledge of such aspects can aid pest management and in turn improve food security and human health. The patterns and processes of the population dynamics of Rattus argentiventer, in rice fields of Indonesia, and Rattus tanezumi, in rice fields of the Philippines were assessed in this article. RESULTSThe meta-analysis of trapping data over 20 years in Indonesia, and 16 years in the Philippines indicated that rodent populations in rice fields did not show a regular multi-annual pattern. Rattus argentiventer populations in Indonesia responded to less rainfall from the current year. Rattus tanezumi populations in the Philippines responded positively to both rainfall and rainfall anomaly with a 1-year time lag. CONCLUSIONSOur study of long-term population data indicates that certain combinations of rainfall parameters could be useful to predict years when there is higher rodent abundance in rice fields. The key rodent pest species in rice fields in Indonesia (R. argentiventer) and the Philippines (R. tanezumi) differ, and the populations of each species respond differently to rainfall anomalies. Other factors such as crop cover and water availability may also be important and should be considered in future work. (c) 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Evidence-based information for smallholder farmers on where and when to conduct rodent management is vital given that most are resource poor and depend on agriculture for food and income. However, there is scarce information on how the foraging activity of rodent pests changes over agricultural cropping seasons. We used the concepts of giving-up-density (GUD) and landscape of fear to monitor how the foraging activity of rodent pests changes in and around maize (Zea mays) fields over the cropping season. We tested the hypothesis that the foraging activity of rodent pests will be influenced by vegetation cover, perceived predation risk and food availability. Mastomys natalensis was the dominant species in all maize fields (n = 3, 87.05 % of the total captures). We observed that the foraging activity of rodents was influenced by vegetation cover and food availability. During the germination stage, rodent activity in the natural habitat and along the border was higher than inside the maize fields. During land preparation, planting, weeding, maize tasselling, maturity, and post-harvest stages, there was no difference in the foraging activity in and around the maize fields. During the harvest stage, the foraging activity was higher in the maize fields than along the border and in the natural habitat. These results can be used to guide smallholder farmers where and when to focus rodent control measures during different stages of the cropping season. An additional approach would be to develop strategies that could potentially increase rodent fear perceptions in cropping landscapes.

Integrative ZoologyVolume 19, Issue 1 p. 2-7 EDITORIAL Rodent biology and ecologically based rodent management (EBRM)—25 years of progress through promoting multidisciplinary research Grant R. SINGLETON, Grant R. SINGLETON Natural Resources Institute, University of Greenwich, Kent, UKSearch for more papers by this authorLyn A. HINDS, Corresponding Author Lyn A. HINDS [email protected] CSIRO Health and Biosecurity, Canberra, ACT, Australia Correspondence: Lyn A. Hinds, CSIRO Health and Biosecurity, GPO Box 1700, Canberra, ACT 2601, Australia. Email: [email protected]Search for more papers by this authorRhodes MAKUNDI, Rhodes MAKUNDI African Centre of Excellence for Innovative Rodent Pest Management and Biosensor Technology Development, Sokoine University of Agriculture, Morogoro, Tanzania Institute of Pest Management, Sokoine University of Agriculture, Morogoro, TanzaniaSearch for more papers by this authorSteven R. BELMAIN, Steven R. BELMAIN Natural Resources Institute, University of Greenwich, Kent, UKSearch for more papers by this author Grant R. SINGLETON, Grant R. SINGLETON Natural Resources Institute, University of Greenwich, Kent, UKSearch for more papers by this authorLyn A. HINDS, Corresponding Author Lyn A. HINDS [email protected] CSIRO Health and Biosecurity, Canberra, ACT, Australia Correspondence: Lyn A. Hinds, CSIRO Health and Biosecurity, GPO Box 1700, Canberra, ACT 2601, Australia. Email: [email protected]Search for more papers by this authorRhodes MAKUNDI, Rhodes MAKUNDI African Centre of Excellence for Innovative Rodent Pest Management and Biosensor Technology Development, Sokoine University of Agriculture, Morogoro, Tanzania Institute of Pest Management, Sokoine University of Agriculture, Morogoro, TanzaniaSearch for more papers by this authorSteven R. BELMAIN, Steven R. BELMAIN Natural Resources Institute, University of Greenwich, Kent, UKSearch for more papers by this author First published: 07 December 2023 https://doi.org/10.1111/1749-4877.12792Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat REFERENCES Awoniyi AM, Venegas-Vargas C, Souza FN et al. (2022). Population dynamics of synanthropic rodents after a chemical and infrastructural intervention in an urban low-income community. 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Rice production in the Central Plains of Thailand plays a key role in the country’s food security. However, the overuse of inputs coupled with the rising production costs are making it increasingly difficult for smallholder rice farming to remain economically and environmentally sustainable. Replicated production-scale field trials of Cost Reduction Operating Principles (CROP)—Thailand’s national package of best management practices for rice production—were established in tandem with laser land leveling (LLL), mechanical drum seeder, and the application of two biofertilizer products (i.e., PGPR II, that contains Azospirillum brasilense Sp. TS29 and Burkholderia vietnamiensis S45; and LDD #12, that contains Azotobacter tropicalis, Burkholderia unamae and Bacillus subtilis) and compared with farmer’s practices (FP). Performance indicators (PI) promoted by the Sustainable Rice Platform (SRP) were used to assess economic and environmental indicators. CROP + PGPR had significantly higher net income (79%) and nitrogen-use efficiency (57%) compared with FP. Pesticide use (28%), seed (60%), inorganic fertilizer N (41%) and total production costs (19%) were reduced in all CROP treatments compared with FP. These results demonstrate that the application of CROP, LLL, mechanical drum seeder, and biofertilizers can substantially improve the economic and environmental sustainability of rice production in the Central Plains of Thailand.

Rice is the dominant food staple and an important economic resource throughout Asia. Lowland rice production also provides important wetland habitats in support of biodiversity that may provide ecosystem services back to the rice agroecosystem. This review summarizes the literature on the ecosystem benefits that amphibians, birds, bats, and rodents support in the context of the Southeast Asia rice agroecosystem. The literature provides evidence that these taxonomic groups contribute to cultural, regulatory, and provisioning services in support of smallholder farmers and may allow for economic benefits through reduced use of chemical inputs into crops. We encourage a community-based participatory research approach to bring stakeholders together to provide structured and scalable education programs that will lead to improved human and agroecosystem health through the promotion of understanding the positive feedbacks from biodiversity in these important agricultural wetland habitats.

AbstractRice production significantly contributes to greenhouse gas emissions (GHGE), especially methane (CH4) emissions at various cropping stages. A major source of methane emissions is the decomposition of fertilizers and organic residues in flooded fields during the irrigation cycle. CORIGAP technologies and practices are mainly associated with closing yield gaps by increasing productivity and profitability but have been co-designed to address climatic challenges and to minimize negative environmental impacts. Therefore, over the last decade, the CORIGAP interventions not only helped to reduce yield gaps substantially but also resulted in a significant reduction of the carbon footprint (CF) in rice production. This chapter starts with an in-depth synthesis of scientific-based evidence and knowledge on challenges and constraints to reducing rice CF in CORIGAP countries. The chapter introduces solutions that have been proven to reduce GHGE, in particular, Alternate Wetting and Drying (AWD), rice-straw management, mechanization, and postharvest management. The latter two approaches include laser land leveling, mechanized direct seeding and transplanting, and paddy grain drying will be described in more detail. In addition, life cycle assessments will outline the quantification of the carbon footprint in rice production, for these specific technologies. The chapter presents three country case studies (Thailand, Indonesia, and Vietnam) from data collected through CORIGAP activities to estimate GHGE reductions associated with implementation of best practices for lowland irrigated rice production. Lastly, this chapter provides the outcomes related to GHGE reduction and offers specific recommendations that can be easily implemented in other countries.

BACKGROUND:Trapping is a key method for monitoring small mammals and is also one of a number of methods recommended under an ecologically-based rodent management program to control rodent pest populations. Live-traps are widely used globally for studying small mammal populations. In Asia where rodents are major pests of rice, single capture traps typically provide low trap success. We compared the trap success between two types of live-traps in rice fields in Indonesia and the Philippines. RESULTS:Multiple-capture traps (MCTs) in conjunction with a linear trap barrier were significantly more effective in catching rodent pest species than single-capture traps (SCTs) in Indonesia and the Philippines. In Indonesia, MCTs captured more individuals with a mean (±SE) percent trap success rate of (15.54 ± 4.29) compared to SCTs (3.88 ± 1.58). In the Philippines, MCTs captured more species of rodents and had a significantly higher recapture rate (1.96 ± 0.79), than SCTs (0.58 ± 0.32). CONCLUSION:Multiple-capture traps with a linear trap-barrier were more effective for capturing Rattus argentiventer and Rattus tanezumi in rice field ecosystems compared to single-capture traps. MCTs captured more species of rodent pests in the Philippines and recaptured more individuals of each species. These results indicate that rodent populations can be more effectively monitored and controlled by using a multi-capture trap with barrier system than the use of single capture traps on their own. This is the first time these two trap types have been compared for use in rice ecosystems in Asia. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

In Myanmar, 70% of the rural population engages in rice farming for their livelihoods. Since 2013, the government and development projects have introduced a variety of sustainable rice cultivation practices such as improved fertilizer-, water-, pest- and post-harvest management. A mixed method approach was used to gain a better understanding of adoption behaviour and livelihood changes. One hundred and twenty nine farmers participated in the study which revealed the adoption of sustainable practices; reasons include higher yields, reduced costs and labour savings. Reasons for non-adoption included unsuitable or expensive practices. We find that profitability analysis and partial budgeting calculations revealed an estimated increase in income (>0) of 113 USD/ha (SD = 90.64 USD/ha), due to an increase in yield and reduced costs. Furthermore, in-depth interviews revealed that farmers (n = 32) used this extra income for religious and social activities, for food, health care and education. They were able to expand their farm business and produce rice more sustainably. The paper thus contributes to the adoption literature by linking development project outputs to outcomes and impact. Concerted efforts by the government and development projects can enable farmers to produce cereals more sustainably and experience positive changes to their livelihoods and strengthen rural development at local and regional level.

CONTEXT: Recent studies on yield gap analysis for rice in Southeast Asia revealed different levels of intensification across the main 'rice bowls' in the region. Identifying the key crop management and biophysical drivers of rice yield gaps across different 'rice bowls' provides opportunities for comparative analyses, which are crucial to better understand the scope to narrow yield gaps and increase resource-use efficiencies across the region. OBJECTIVE: The objective of this study was to decompose rice yield gaps into their efficiency, resource, and technology components and to map the scope to sustainably increase rice production across four lowland irrigated rice areas in Southeast Asia through improved crop management.METHODS: A novel framework for yield gap decomposition accounting for the main genotype, management, and environmental factors explaining crop yield in intensive rice irrigated systems was developed. A combination of crop simulation modelling at field-level and stochastic frontier analysis was applied to household survey data to identify the drivers of yield variability and to disentangle efficiency, resource, and technology yield gaps, including decomposing the latter into its sowing date and genotype components.RESULTS AND CONCLUSION: The yield gap was greatest in Bago, Myanmar (75% of Yp), intermediate in Yogyakarta, Indonesia (57% of Yp) and in Nakhon Sawan, Thailand (47% of Yp), and lowest in Can Tho, Vietnam (44% of Yp). The yield gap in Myanmar was largely attributed to the resource yield gap, reflecting a large scope to sustainably intensify rice production through increases in fertilizer use and proper weed control (i.e., more output with more inputs). In Vietnam, the yield gap was mostly attributed to the technology yield gap and to resource and efficiency yield gaps in the dry season and wet season, respectively. Yet, sustainability aspects associated with inefficient use of fertilizer and low profitability from high input levels should also be considered alongside precision agriculture technologies for site-specific management (i.e., more output with the same or less inputs). The same is true in Thailand, where the yield gap was equally explained by the technology, resource, and efficiency yield gaps. The yield gap in Indonesia was mostly attributed to efficiency and technology yield gaps and yield response curves to N based on farmer field data in this site suggest it is possible to reduce its use while increasing rice yield (i.e., more output with less inputs).SIGNIFICANCE: This study provides a novel approach to decomposing rice yield gaps in Southeast Asia's main rice producing areas. By breaking down the yield gap into different components, context-specific opportunities to narrow yield gaps were identified to target sustainable intensification of rice production in the region.

Rice paddies are unique ecosystems that provide rich wetland habitat. Their enduring existence across vast stretches of land has led them to evolve into unique systems serving a diverse assemblage of organisms and sustaining a staple grain for many people. With food demand rising, agricultural intensification through agrochemical application is a common practice used to boost food production in developing countries, including Sri Lanka. The aim of the present study was to assess the concentration of pesticide residues in water in rice ecosystems and discover their potential impacts on both environmental health and the most common fauna groups across a cropping year in Sri Lanka. A total of 270 water samples from waters associated with paddy fields within a watershed were analyzed for 20 commonly used pesticides; in addition, local farm holders were surveyed to assess pesticide usage details in three selected paddy tracts. We then used the Cornell University environmental impact quotient (EIQ) calculator and the ECOTOX Knowledgebase to determine the exposure risk associated with individual pesticides relative to their application rates and aquatic concentrations. Survey results demonstrate that several pesticides were overapplied at rates 1.2–11 times the recommended application, and the EIQ demonstrated high environmental risk of two of the agrochemicals detected, 2‐methyl‐4‐chlorophenoxyacetic and diazinon. Fish, amphibians, insects, and beetles were found to have a wide range of potential adverse outcomes from exposure to diazinon, captan, thiamethoxam, and chlorantraniliprole. To balance the trade‐offs between food security and ecosystem sustainability, the present study recommends that adoption of quantifiable environmental health indicators be considered as part of the national policy regulating pesticide use. Environ Toxicol Chem 2022;41:343–355. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

The desire to increase agricultural productivity through the high usage of agrochemicals is causing substantial environmental deterioration. Many developing countries lack the capacity to quantify agro-pollution, especially in the case of chemical inputs such as pesticides, preventing them from formulating action plans to mitigate the negative environmental impacts of agro-chemicals. This study aims to address the knowledge gap in Sri Lanka by assessing water quality at a temporal and geospatial scale, focusing on areas with significant agricultural inputs in the Deduru Oya river basin of Sri Lanka. To assess water quality, 183 samples were collected biweekly in the 2019 dry season (Yala) and 2019/2020 wet season (Maha) and analyzed for 39 parameters, including pesticides, heavy metals, minerals and physico-chemical properties. Of the twenty pesticides tested, ten were detected in the water samples (pretilachlor, oxyfluorfen, thiamethoxam, chlorantraniliprole, fenobucarb, fipronil, diazinon, etofenprox, tebuconazole, and captan) and concentrations of all detected pesticides exceeded national regulatory threshold limits. Heavy metal residues were not detected in the water. Pesticide and mineral levels varied widely and exhibited lack of evenness across seasons and locations. Pesticide contamination was higher in the wet season than the dry season. Temporal variation was more pronounced than spatial variation for many of contaminants. No clear trend in contaminant accumulation was observed as sampling progressed downstream from the main reservoir. In both seasons, natural or inorganic fertilizer mineralization and pesticide inputs into the agricultural systems were identified as the main factors underlying water pollution in the study area.

Overuse of seed and chemical inputs is a major constraint for sustainable rice production in Vietnam. In this study, two seasons of field trials were conducted to compare different crop establishment practices for rice production in the Mekong River Delta using environmental and economic sustainability performance indicators. The indicators including energy efficiency, agronomic use efficiency, net income, and greenhouse gas emissions (GHGEs) were quantified based on four treatments including manual broadcast-seeding, blower seeding, drum seeding, and mechanized transplanting. Across the four treatments, yields ranged from 7.3–7.5 Mg ha−1 and 6.2–6.8 Mg ha−1 in the Winter-Spring (WS) and Summer-Autumn (SA) seasons, respectively. In comparison with direct seeding methods, mechanized transplanting decreased the seed rate by 40%. It also led to a 30–40% reduction in pesticide use during the main crop season (WS). Mechanized transplanting required higher inputs, including machine depreciation and fuel consumption, but its net energy balance, net income and GHGE were at a similar level as the other non-mechanized planting practices. Mechanized transplanting is a technology package that should be promoted to improve the economic and environmental sustainability of lowland rice cultivation in the Mekong River Delta of Vietnam.

The advent of ‘conservation agriculture’ (CA) farming using zero- or no-tillage practices and an accompanying change in crop rotations in the last 10–15 years has potentially led to less disturbance of mouse burrows and increased cover and food supply. Given the irregular outbreaks of mice in grain cropping regions in Australia and the damage they cause, it is important to understand when and where mouse populations increase so that management strategies can be improved. We utilised a 20-year long-term mouse population data set collected prior to the introduction of CA farming practices and a more recent 8-year data set after CA to compare changes in mouse population abundance in a typical dryland grain cropping system in north-western Victoria, Australia. Mouse trapping data were used to compare abundance in crop and margin habitats during crop growth and non-crop (fallow) periods before (‘conventional’) and after introduction of CA. Mice are now resident year-round within crops and stubble and appear to only spill over into margin habitats. Previously developed recommendations for mouse management that include their control while in margin habitats may no longer be valid.

Several rodent species damage rice crops and commensal rodents cause damage to stored produce and infrastructure, hygienic problems and they can transmit zoonotic pathogens. In the first such study in Sri Lanka, we identified the main rodent and shrew species and the extent of post-harvest damage caused in rice storage facilities of smallholder farmers. Netting of rice bags was trialled as a new measure of protection. Field experiments were performed in the three main agro-ecological zones of Sri Lanka. Five rodent species and one shrew species were captured in storage facilities. Rattus rattus, Bandicota indica and Suncus murinus were the dominant species in storage facilities. The small mammal composition was more related to season than to region. In storage, depending on region, 3.2?9.1% (mean 7.6%) of rice was lost to rodents when rice was stored indoors in unprotected polyethylene bags. Netting around bags reduced damage by 89% equivalent to the annual rice consumption of one person per storage facility, reduced the presence of rodent droppings by 92% and the bag area damaged by rodents by 96%. Our findings clearly show the considerable amount of damage caused by rodents to rice post-harvest across three agro-ecological zones of Sri Lanka and indicate that netting bags considerably reduces damage and contamination. This netting can be used to aid the development of an ecologically-based rodent management (EBRM) program tailored to local conditions. More detailed studies are needed to fully understand the population and breeding ecology of the relevant rodent pest species in relation to damage patterns to optimize management beyond individual structural measures.

The rice field rat, Rattus argentiventer, is a significant pest of rice in Southeast Asia. Fertility control methods have the potential to provide safe and effective alternatives to control methods that often include indiscriminate use of rodenticides or electric barriers. The aim of this laboratory study was to assess uptake of bait coated with different concentrations of the contraceptive hormones, quinestrol (E) and levonorgestrel (P), delivered alone and in combination (i.e. EP-1) and determine the short-term effects on reproductive parameters of adult male and female R. argentiventer. In Experiment 1, 2 concentrations of E, P, and EP-1 (10, 20 ppm) were fed to groups of wild-caught rats for 7 days. In females, both E and EP-1 induced uterine edema. In males, EP-1 reduced epididymis and seminal vesicle weights and lowered sperm motility. However, these responses were inconsistent due to low bait acceptance, especially with increasing concentrations. In Experiment 2, EP-1 (0, 20, 50, 100 ppm) was administered by oral gavage daily for 7 days to male R. argentiventer. There were significant reductions in epididymal and seminal vesicle weights for all oral doses of EP-1, in sperm counts for the 50 ppm dose, and in sperm motility for the 20 and 50 ppm doses compared to the control group. To select the optimum dose of EP-1, we must address the poor acceptance of contraceptive-coated baits by rice field rats. Further research is required to improve the palatability of EP-1 and to test its uptake under field conditions.

The multimammate mouse, Mastomys natalensis, is the most common rodent pest species in sub-Saharan Africa. Currently, rodenticides are the preferred method used to reduce the population of rodent pests, but this method poses direct and indirect risks to humans and other non-target species. Fertility control is a promising alternative that has been argued to be a more sustainable and humane method for controlling rodent pests. In this study, we compared the effectiveness of fertility control bait EP-1 (quinestrol (E) and levonorgestrel (P), 10 ppm) and an anticoagulant rodenticide bait (bromadiolone, 50 ppm) on the population dynamics of M. natalensis in maize fields in Zambia during 2 cropping seasons. M. natalensis was the most abundant species in maize fields (77% of total captures). Fertility control reduced the number of juveniles and suppressed population growth of M. natalensis at the end of the 2019-2020 cropping season. The population density initially decreased after rodenticide treatment, but the population rapidly recovered through immigration. None of the treatments influenced maize damage by rodents at germination (F2,67 = 1.626, P = 0.204). Applying the treatments during the maize seeding time was effective at suppressing population growth at the end of the cropping season than application the month before maize seeding. This research indicates that a single-dose delivery of EP-1 and rodenticide have comparable effects on the population dynamics of M. natalensis. These findings are important in developing fertility control protocols for rodent pest populations to reduce maize crop damage and improve yields.

Pneumocystis fungi are opportunistic parasites of mammalian lungs whose evolution, ecology and host specificity in natural host populations remain poorly understood and controversial. Using an extensive collection of 731 lung samples from 27 rodent species sampled in five Southeast Asian countries, and nested PCR amplification of mitochondrial and nuclear genes, we investigated the host specificity and genetic structure of Pneumocystis lineages infecting wild rodents. We also identified the rodent species playing a central role in the transmission of these parasites using network analysis and centrality measurement and we characterized the environmental conditions allowing Pneumocystis infection in Southeast Asia using generalized linear mixed models. Building upon an unprecedented Pneumocystis sampling from numerous rodent species belonging to closely related genera, our findings provide compelling evidence that the host specificity of Pneumocystis lineages infecting rodents is not restricted to a single host species or genus as often presented in the literature but it encompasses much higher taxonomic levels and more distantly related rodent host species. The phylogenetic species status at both mitochondrial and nuclear genetic markers of at least three new Pneumocystis lineages, highly divergent from Pneumocystis species currently described, is also suggested by our data. Our models show that the probability of Pneumocystis infection in rodent hosts is positively correlated to environmental variables reflecting habitat fragmentation and landscape patchiness. Synanthropic and habitat-generalist rodents belonging to the Rattus, Sundamys and Bandicota genera played a role of bridge host species for Pneumocystis spreading in these heterogeneous habitats, where they can reach high population densities. These are critical findings improving our understanding of the ecology of these enigmatic parasites and the role played by cospeciation and host switches in their evolution. Our results also confirmed the role of land-use change and habitat fragmentation in parasite amplification and spillover in rodents.

Identifying the adverse impacts of pesticide exposure is essential to guide regulations that are protective of wildlife and human health. Within rice ecosystems, amphibians are valuable indicators because pesticide applications coincide with sensitive reproductive and developmental life stages. We conducted two experiments using wild cane toads (Rhinella marina) to test 1) whether environmentally relevant exposure to a commercial formulation of butachlor, an acetanilide herbicide used extensively in rice, affects amphibian development and 2) whether cane toad tadpoles are capable of acclimatizing to sub-lethal exposure. First, we exposed wild cane toads to 0.002, 0.02, or 0.2 mg/L of butachlor (Machete EC), during distinct development stages (as eggs and hatchlings, as tadpoles, or continuously) for 12 days. Next, we exposed a subset of animals from the first experiment to a second, lethal concentration and examined survivorship. We found that cane toads exposed to butachlor developed slower and weighed less than controls, and that development of the thyroid gland was affected: exposed individuals had smaller thyroid glands and thyrocyte cells, and more individual follicles. Analyses of the transcriptome revealed that butachlor exposure resulted in downregulation of transcripts related to metabolic processes, anatomic structure development, immune system function, and response to stress. Last, we observed evidence of acclimatization, where animals exposed to butachlor early in life performed better than naïve animals during a second exposure. Our findings indicate that the commercial formulation of butachlor, Machete EC, causes thyroid endocrine disruption in vertebrates, and suggest that exposure in lowland irrigated rice fields presents a concern for wildlife and human health. Furthermore, we establish that developmental assays with cane toads can be used to screen for adverse effects of pesticides in rice fields.

Sustainability of rice production systems is a prime concern for Asia to maintain food security and to support economic growth. This gain in productivity not only depends on agricultural inputs but also depends on social and environmental factors. To address these emerging issues, new resource- and capital-efficient and profitable technologies have been introduced. The conventional method of rice production (puddling and manual transplanting, PTR) is considered as highly input intensive. As an alternative, dry direct seeded rice (DSR) using seed drill has been promoted to save labor and production costs compared with PTR. Similarly, machine transplanted rice (MTR) has been also considered and promoted in many rice growing countries of South and East Asia. Economic, environmental, and social performances of DSR and MTR (alternative rice establishment technologies) were compared to the PTR using Sustainable Rice Platform (SRP) defined 12 Performance Indicators (PIs) (version 1.0) as a gauge to measure their sustainability. For that, a household survey was conducted on 652 households in Odisha India during 2016. The gaps, i.e., the target to achieve better sustainability, were computed for most of the indicators from the difference between top 10th percentile and the population mean value of the indicator. The results indicated a yield gap of 1.35 t ha(-1) , a profit gap of $273 ha(-1), labor productivity gap of 21 kg day(-1), nitrogen (N) use efficiency gap of 22 kg grain kg(-1) N, phosphorus (P) use efficiency gap of 105 kg grain kg(-1) P, and water productivity gap of 0.00010 kg grain L-1 water in rice production systems in Odisha. Among the compared technologies, MTR results in the highest yield, profit, labor productivity, nitrogen-, phosphorus-use efficiency, and water productivity (at par), and is positive for children's welfare and the overall energy productivity, indicating better sustainability and has the potential to replace PTR. Direct seeded rice has the highest yield gap (1.57 t ha(-1); 38%) but has the lowest production cost (can reduce the cost of production by $130 ha(-1)), and the highest greenhouse gas (GHG) reduction potential. SRP PIs are capable for assessing the sustainability of rice establishment technologies except for a few indicators, for example food safety and workers health and safety, which are more applicable to watershed and household level indicators, respectively. The SRP PIs provide scientific evidence and practical impetus for the selection and promotion of sustainable rice production technologies. (C) 2019 The Authors. Published by Elsevier Ltd.

Post-harvest losses by rodents are estimated to be similar as for pre-harvest losses; somewhere from 0.25% to 25% or more, but generally considered to average around 5-10%, which is similar to the level of post-harvest losses caused by insects. There have been very few studies measuring post-harvest rodent damage and losses. The main pests are the widespread commensal rodent species. Rodents cause direct losses by consuming grain, but they also spoil grain (contamination with hair, urine and faeces), and expose grains to further mould or insect damage. There is a risk of transfer of diseases and zoonoses to humans and livestock. Rodents damage infrastructure such as the warehouses and stores themselves, but also cables and water pipes. There is little information about the ecology of the main rodent pest species in grain stores. Therefore, this remains an important research topic to improve management recommendations about the timing and location of control strategies.