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Background: The spider family Sicariidae Keyserling, 1880 represented by the synanthropic Mediterranean recluse spider, Loxosceles rufescens (Dufour, 1820), is reported in the Philippines for the first time, based on morphological and molecular data. The introduced spider was observed in a small cave (Kamantigue Cave) in Lobo, Batangas Province. Considering the medical importance of this spider, the proximity of its habitat to human habitation and tourist sites poses a potential public health concern. New information: This study reports on the first record of the family Sicariidae in the Philippines and the fourth recorded occurrence of L. rufescens in Southeast Asia. [ABSTRACT FROM AUTHOR]

In today's culture, some people think that because they are struggling financially, they can simply relocate and start working as soon as they graduate from high school. This is especially true for females who were judged to have continued with college if premarital sex or teenage pregnancies prevented them from finishing. However, this may not be the case. The first-generation female graduates' lived experiences were examined in this phenomenological study with an emphasis on their lived experiences before, during, and after college, and their aspirations for the future. Using a transcendental research design based on Moustakas' Stevick-Colaizzi-Keen approach, the study's key themes, and the essence of the study's findings were developed. Eight graduates of the City College of Calamba were selected as participants through purposeful sampling. Data analysis revealed that being a financially challenged student means college survival through selfsupport. Their goals for their families were crucial to their diligence and success in the courses. It reflects their struggles with finishing, which is the essence of surviving by doing major things (working and studying) simultaneously. Furthermore, their experiences of surviving are diverse in how they are shaped and re-shaped by pursuing learning and finishing. The study shows that four challenging long years of college are worth fighting for since they achieved a 360-degree twist in their lives and are now an inspiration for other members of the family and other people who know them. [ABSTRACT FROM AUTHOR]

Actual observations and documentation of cacao pests feeding on the pods in the field are very few. The cacao mirid bug, Helopeltis bakeri Poppius, was laboratory-reared and released [21 pairs = Tree 1; 17 pairs = Tree 2; 21 pairs = Tree 3] in three randomly chosen cacao trees under controlled settings from October 2019-March 2020 with the aim of observing and documenting cacao pests feeding on the pods in the field to have insights into the proper pest action threshold. A coefficient score of 4.93 on a 0-5 rating scale described "heavy damage" as > 50% of feeding lesion marks on 28 out of 30 pods (93%) were visible. The first feeding lesions were observed in an average of 37 days but came as early as 10 d upon release of H. bakeri. Within this time of observing the initial feeding lesions, there would only be 39 d before the whole pod is scorched due to black pod disease. The study shows the harmfulness of this cacao pest and highlights the need for integrated pest management to reduce the reliance on chemical control, which has been the default strategy for too long. [ABSTRACT FROM AUTHOR]

The fruit and vegetable sector produce waste significantly, causing social, environmental, and economic loss. Thus, a study was conducted at Pasig Mega Market, Pasig City to describe the fruit and vegetable vendors' waste management practices. Vendors and government employees participated in focus group discussions and key informant interviews. Results showed an average of 100-200 kilograms of waste were collected in the market daily, with leafy vegetables, watermelon, melon, and saba as common types. Focus group discussions revealed that discounted prices for suboptimal items, quality assurance methods, adherence to First-In-First-Out principles, and marketing strategies were the vendors' efforts to reduce waste. The identified approaches in handling wastes were, giving them as animal feed, creating alternative products, and returning damaged products to suppliers. Key informant interviews disclosed that the local government and market administration practices in waste management were composting and donation as animal feed for the local zoo. Moreover, it revealed improvement in the management of implementing the ordinances. Problems encountered were focused on supplier issues, weather, market competition, and consumer preferences. Overall, their waste management reduces food waste disposed of in landfills. Recommended strategies for vendors and administration are valorizing food waste, organizing awareness and livelihood programs, and conducting regular evaluations. [ABSTRACT FROM AUTHOR]

Co-designing research-informed guidelines with youth for adapting research methods to other contexts has received little research attention. We report on guidelines co-designed with youth for adapting arts-based methods (ABM) for youth mental health (MH) research in online environments. Seven youth co-researchers participated in 3 co-design workshops and 2 graphic recording focus groups. Data analysis involved a thematic analysis approach. We identified one overarching theme (sustaining mindful presence when conducting research) and 4 subthemes (creating a safe space, youth having a say, facilitating meaningful engagement, paying receptive attention throughout the research process). Facilitating participants' authentic expression in online environments requires: 1) Letting youth self-identify; 2) incorporating diversity and inclusion; 3) providing accommodations, recognition, and compensation; 4) language considerations; 5) offering ABM training and resources for creating art; 6) using virtual platforms youth use; 7) being mindful of ethical considerations and technology fatigue; 8) addressing barriers in accessing and using technology; 9) providing choice in type of ABM and research methods used; and 10) providing options for communicating during research activities and for engaging in research outside of allotted time (e.g., email, group chat). These research-informed guidelines can be useful for conducting youth MH research and other youth research in online environments. [ABSTRACT FROM AUTHOR]

The unique Philippine spiny stick insect genus Stenobrimus, was reviewed. One new species, S. pilipinus Eusebio, Lit & Lucañas, sp. nov., is described from the forest over limestone outside the Cavinti Underground River and Cave Complex (CURCC) in Cavinti, Laguna Province. S. pilipinus, sp. nov., is unique among Stenobrimus species in having post-median mesonotal spines in both males and females. Its morphologically nearest congeners, S. bolivari Redtenbacher and S. tagalog Rehn & Rehn, are redescribed. The distribution of the genus in relation to karst forests and the historical biogeography of the Philippines is briefly discussed. Revised keys to the identification of Stenobrimus species for males, females, and eggs are presented. [ABSTRACT FROM AUTHOR]

Co-designing research-informed guidelines with youth for adapting research methods to other contexts has received little research attention. We report on guidelines co-designed with youth for adapting arts-based methods (ABM) for youth mental health (MH) research in online environments. Seven youth co-researchers participated in 3 co-design workshops and 2 graphic recording focus groups. Data analysis involved a thematic analysis approach. We identified one overarching theme (sustaining mindful presence when conducting research) and 4 subthemes (creating a safe space, youth having a say, facilitating meaningful engagement, paying receptive attention throughout the research process). Facilitating participants' authentic expression in online environments requires: 1) Letting youth self-identify; 2) incorporating diversity and inclusion; 3) providing accommodations, recognition, and compensation; 4) language considerations; 5) offering ABM training and resources for creating art; 6) using virtual platforms youth use; 7) being mindful of ethical considerations and technology fatigue; 8) addressing barriers in accessing and using technology; 9) providing choice in type of ABM and research methods used; and 10) providing options for communicating during research activities and for engaging in research outside of allotted time (e.g., email, group chat). These research-informed guidelines can be useful for conducting youthMH research and other youth research in online environments. [ABSTRACT FROM AUTHOR]

This study aimed to examine the phytochemical levels of crude "tabon-tabon" (Atuna racemosa Raf.) fruit extracts subjected to air-drying, oven-drying, and freeze-drying. It also sought to validate the claims of previous literature on the fruit's antimicrobial properties by using its aqueous extracts as an antibacterial wash for green ice leaf lettuce. Phytochemical analysis revealed significantly higher (p < 0.05) levels of alkaloids and tannins compared to coumarins, saponins, and terpenoids. The highest alkaloid content (16.25 ± 1%) was obtained using ovendrying, whereas the highest tannin content was obtained using freeze-drying (14.14 ± 1.13%). In vivo antibacterial assay against Escherichia coli was performed to test the aqueous extracts alongside 200 ppm chlorine solution and water for comparison. Artificially-inoculated lettuce samples were individually soaked in 15-mL solution at 2- and 5-min contact times. Bacterial load was determined at a 2-d interval for a period of 8 d. Results of the microbiological analysis showed no significant interaction in the soaking time used. However, the treatments were independently found to have significant effects on Days 0, 4, and 6. The highest antibacterial effect in green ice lettuce was exhibited up to Day 6. [ABSTRACT FROM AUTHOR]

Global biodiversity decline is continuing largely unabated. The International Union for Conservation of Nature (IUCN) Red List of Threatened Species (hereafter, Red List) provides us with the gold standard for assessments, but taxonomic coverage, especially for invertebrates and fungi, remains very low. Many players contribute to the Red List knowledge base, especially IUCN Red List partners, IUCN-led assessment projects, and the Specialist Groups and Red List Authorities (RLA) of the IUCN Species Survival Commission. However, it is vital that we develop the next generation of contributors and bring in new, diverse voices to build capacity and to sustain the huge assessment effort required to fill data gaps. Here, we discuss a recently established partner network to build additional capacity for species assessments, by linking academia directly into the assessment processes run by Specialist Groups and RLAs. We aim to increase Red List "literacy" amongst potential future conservationists and help students to increase publication output, form professional networks, and develop writing and research skills. Professors can build Red List learning into their teaching and offer Red Listing opportunities to students as assignments or research projects that directly contribute to the Red List. We discuss the opportunities presented by the approach, especially for underrepresented species groups, and the challenges that remain. [ABSTRACT FROM AUTHOR]

Mass media plays an important role in the construction and circulation of risk perception associated with animals. Widely feared groups such as spiders frequently end up in the spotlight of traditional and social media. We compiled an expert-curated global database on the online newspaper coverage of human-spider encounters over the past ten years (2010–2020). This database includes information about the location of each human-spider encounter reported in the news article and a quantitative characterisation of the content—location, presence of photographs of spiders and bites, number and type of errors, consultation of experts, and a subjective assessment of sensationalism. In total, we collected 5348 unique news articles from 81 countries in 40 languages. The database refers to 211 identified and unidentified spider species and 2644 unique human-spider encounters (1121 bites and 147 as deadly bites). To facilitate data reuse, we explain the main caveats that need to be made when analysing this database and discuss research ideas and questions that can be explored with it. Measurement(s) Newspaper articles on human-spider encounters Technology Type(s) Manual extraction Sample Characteristic - Organism Spiders (Arachnida: Araneae) Sample Characteristic - Environment Online Sample Characteristic - Location Global [ABSTRACT FROM AUTHOR]

Helopeltis bakeri Poppius is a major insect pest of cacao, Theobroma cacao L. in the Philippines. It is one of the four Helopeltis species endemic to the Philippines, easily recognizable for its sexual dimorphism. Up to date, no developmental biology and host plant list have been recorded for H. bakeri. Here, we report its life history, conduct surveys, and present potential host plant species. Biological characteristics of H. bakeri reared on Ipomea batatas (L.) Poir. shoots were observed in the laboratory at 27 ± 1 °C, 59 to 73% RH, and L12:D12. Five nymphal stages were recorded. Egg incubation period was 7.49 ± 0.43 days, and the duration of each of the five developmental stages was 3.11 ± 0.53, 1.51 ± 0.37, 2.07 ± 0.11, 4.40 ± 0.32 and 4.45 ± 0.17 days, respectively. Adult longevity was not significantly different between both sexes. We also provided morphological descriptions and measurements of the immature stages to aid proper nymphal identification of H. bakeri. No choice tests and field observations revealed four potential host plants, i.e., Chromolaena odorata (L.) R King & H Robinson, Cucumis sativus L., Hibiscus rosasinensis L., and Psidium guajava L., and two plants, i.e., Polyscias scutellaria (Burm. f.) Fosb. and Ipomea batatas (L.) Poir with confirmed host association. The information gathered on the life history, and host plant associations of H. bakeri would help decide the appropriate pest management strategy for controlling the population of this insect pest in the country's cacao-growing areas. [ABSTRACT FROM AUTHOR]

In the heightened effects of the pandemic, health resources have been in constant limbo as supplies and availability of hospital resources take a toll as COVID-19 cases surge, resulting in shortages. Thus, health systems are overwhelmed, resulting in a higher fatality rate since the capacity to provide medical attention is diminished. In this paper, hospital resources refer to mechanical ventilators, ICU, isolation, and ward beds which are the critical factors of the case fatality rate (CFR) of COVID-19 in the Philippines. Data were retrieved from the Department of Health (DOH) Case Bulletins from October 26, 2020, to June 30, 2021, with 248 total observations. This research used the Ordinary Least Squares (OLS) Multiple Regression to determine if hospital resources are the predictors of the case fatality rate of COVID-19. Furthermore, the results show a significant relationship between the hospital resources and the case fatality rate of COVID-19 in the Philippines. This study can become a framework for further research concerned about hospital resources as the predictors of case fatality rates of different diseases in a pandemic. [ABSTRACT FROM AUTHOR]

One of the primary and underutilized benefits of Model Based Systems Engineering is reuse. Most users of Model Based Systems Engineering lack the understanding of the process involved to develop a project tree that enables use of projects in other projects to facilitate that multi‐dimensional reuse. Although the benefits speak for themselves, few practitioners fully grasp the modeling techniques and rigor necessary to facilitate a model that is fully traced, modular, and reusable. The Model of Models Methodology satisfies these needs, accomplishing the Digital Engineering needs on the project as well as enabling significant time and cost savings. [ABSTRACT FROM AUTHOR]

Papilio chikae and P. hermeli are two endemic swallowtail butterflies in the Philippines found primarily in the Cordillera region and Mindoro Island, respectively. Their species status is still subject to debate due to opposing interpretations of their genitalia and morphological traits. This study aims to delineate these taxa through the use of mitochondrial cytochrome C oxidase subunit I (COI) gene marker, with additional information on their cytochrome C oxidase subunit II (COII) gene. The COI nucleotide sequences from our Philippine P. chikae samples were surprisingly identical to P. hermeli EF514465.1 on the GenBank, whereas our P. hermeli samples showed a 100% similarity with P. hermeli EF514464.1. Based on our phylogenetic analysis, P. chikae and P. hermeli exhibit distinct COI barcodes supported by a high bootstrap value (85%). The P. hermeli voucher specimen with GenBank Acc. No. EF514465.1 clustered with our P. chikae samples, separate from the cluster containing our P. hermeli specimens. Nonetheless, the 3.1-3.4% genetic distance observed in the COI region supported by the formation of two separate clusters suggests species status for these taxa. Moreover, species-specific molecular markers obtained from the COII region displayed a 2.4% distance between these two taxa. These molecular markers could therefore be utilized to distinguish P. chikae from P. hermeli. Nevertheless, a thorough examination of their morphology, behavior, and ecology is still imperative to firmly establish their taxonomic status. [ABSTRACT FROM AUTHOR]

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The iron, zinc, phosphorus, and manganese contents of dehulled and well-milled pigmented and non-pigmented rice varieties were determined. Pigmented rice had the highest mineral content compared to the non-pigmented rice, regardless of variety. However, non-pigmented had higher phosphorus content. Among the non-pigmented rice varieties, Jasmin rice contains the highest zinc content. Sinandomeng contains the highest iron content, IR 64 contains the highest manganese content, and Milagrosa contains the highest phosphorus content. On the other hand, upon comparing the pigmented rice varieties, Dinorado contains the highest zinc and phosphorus content, Perurutong contains the highest iron, and Malagaya Tapul contains the highest manganese content. The dehulled varieties of pigmented rice contain high mineral content compared to well-milled rice. However, Ballatinao and Malagaya Tapul contain high levels of zinc and manganese in well-milled rice and high levels of iron and phosphorus in dehulled rice. [ABSTRACT FROM AUTHOR]

Very little is known about the arthropods associated with the wild ancestors of agricultural crops. Given that wild relatives of crop plants are subjected to human pressures of habitat loss and transgene flow, baseline levels of arthropod biodiversity and community composition are urgently needed to detect declines associated with anthropogenic disturbance. Here, we sampled arthropod abundance and community composition on the wild ancestor of cultivated rice, Oryza rufipogon Griffiths, in the Mekong Delta of Vietnam to ask: 1) Do arthropods associated with O. rufipogon fluctuate temporally and spatially in terms of community composition, diversity, and abundance? 2) What is the abundance and diversity of lepidopteran and hemipteran species associated with O. rufipogon across sites and seasons? We found a total of 578 arthropod taxa, distributed across 178 families in 17 orders. Rarefied species richness and arthropod abundance did not vary across the sampled stands of O. rufipogon, but did vary across the years. Arthropod abundance and metrics dependent upon abundance generally declined over the observation period, suggesting that the sampling effects or other unobservable factors may have contributed to the decline in the arthropod community. Overall, predators dominated the community composition, followed by detritivores and herbivores. Predatory and herbivorous taxa were the most speciose guilds. We found 45 unique taxa of Lepidoptera, many of which were previously undescribed on rice. Given that wild relatives such as Oryza rufipogon support a diverse arthropod community, this study provides a baseline evaluation of the arthropod community in this important native habitat. [ABSTRACT FROM AUTHOR]

Insect pest management depends on simple, rapid, and reliable sampling methods that should also be standardized and optimized. We tested structured inventory, community characterization, and sampling optimization approaches on the invertebrate fauna of Philippine irrigated rice, undisrupted by pesticides, using seven field methods and species richness models. Canopy and floodwater invertebrates were intensively and repetitively sampled from 600 quadrats (~0.1-m² planar area) over dry and wet cropping seasons in one field at the International Rice Research Institute in the Philippines. In the canopy, pooled counts from D-Vac and plant dissections (PD) on the same rice hills ("absolute methodology") were compared with three other methods (i.e., FARMCOP, Blower-Vac, sweep-net), while, in the floodwater, the area collector ("absolute methodology") was compared with three other methods (i.e., FARMCOP, Blower-Vac, strainer-net). Overall, 25 and 50% of the observed richness of canopy and floodwater taxa, respectively, were caught by all four methods. Estimated inventory completeness for the canopy and floodwater averaged 82 and 98%, respectively, after all methods were pooled. To maximize observed richness, optimization results for the canopy recommended allocating the highest sampling effort to D-Vac and PD, followed by the Blower-Vac, whereas the area collector should be assigned the highest sampling effort in the floodwater, followed by the strainer-net or Blower-Vac. Our results suggest that structured inventory and species richness models are useful tools for setting optimization criteria and stopping rules for sampling crop-invertebrate assemblages based on inventory completeness and for enabling more informative biodiversity comparisons. [ABSTRACT FROM AUTHOR]

Although it is well established that biodiversity plays an important role in pest control, there is limited knowledge on how the origins of agriculture may shape arthropod biodiversity. Arthropod food webs likely have coevolved with wild crop relatives before domestication, but not all arthropod taxa may be able to inhabit cultivated habitats. We sampled wild and cultivated rice fields in the Mekong Delta of Vietnam to determine how season (dry versus wet) and rice cultivation influenced arthropod diversity and community composition. We found that cultivated rice fields supported ≈50% fewer taxa than wild rice fields, and that there were widespread losses in taxonomic richness within all of the major orders. Wild rice fields supported 173 unique taxa that were not found in any cultivated rice fields, whereas cultivated rice (Oryza sativa L.) supported only 23 unique taxa. Furthermore, wild and cultivated rice supported different arthropod communities. Predators and parasitoids were the most abundant in wild rice during the dry season. Herbivore densities were similar in wild and cultivated rice, but were reduced in wild rice (Oryza rugipogon L.) during the wet season. Neither season nor habitat influenced the densities of detritivores, but aquatic predators were more abundant during the dry season. This study provides empirical evidence that large-scale losses of species richness and changes in arthropod community structure are associated with the cultivation of domesticated rice. [ABSTRACT FROM AUTHOR]

Replicated field plot trials were carried out to evaluate the role of fish as biocontrol agents of insect pests of rice in the Philippines. Evidence from suction sampling, examination of fish gut contents, and rice plant damage assessment strongly suggest that Common Carp Cyprinus carpio (L.) and Nile Tilapia Oreochromis niloticus (L.) do significantly reduce the densities of stemboring moths and chironomid midges, while the abundance levels of other arthropods are not significantly affected. This impact by fish often was more important in the wet season when heavy rains and wind likely caused the arthropods to become dislodged from the plant and fall onto the water. Predation by fish was particularly evident during the first 45 days of the crop during the wet season when adult chironomid midge abundance was high. The fish gut content analysis revealed that all insect guilds are represented in the diet of both of the fish species regardless of whether the life-cycle of the arthropod prey is aquatic, semi-terrestrial, or terrestrial. Thus, fish in rice fields are part of the assemblage of natural enemies of rice pests. While fish alone cannot completely suppress rice pest populations below the economic threshold, their significant contribution should not be overlooked. [ABSTRACT FROM AUTHOR]

1. Fallowing, a type of rotation where no crop is grown, deprives insect pests of food. In tropical irrigated rice, it is not known whether fallow periods deplete natural enemy populations and reduce their pest control effectiveness in post-fallow crops. We tested the null hypothesis that small-scale synchronous cropping (embedded in asynchronously planted rice landscapes) does not significantly increase pest densities during post-fallow periods in the presence of a large, diverse natural enemy complex undisrupted by insecticides. We tested this null hypothesis by comparing the invertebrate fauna before and after fallowing. 2. In six molluscicide-only fields at the International Rice Research Institute (IRRI) in southern Luzon and at Zaragoza in central Luzon, Philippines, canopy and floodwater invertebrates were vacuum-sampled over two cropping seasons, dry and wet. 3. Thirty-three of the ubiquitous common taxa dominated the samples in both seasons at each site. Most species were natural enemies of rice pests and recyclers of organic matter in the floodwater and waterlogged sediments; some were rice pests. 4. Fallowing depleted populations of more ubiquitous taxa at Zaragoza (four natural enemies, one detritivore) than at IRRI (one herbivore, one natural enemy). At both sites, only green leafhoppers, Nephotettix virescens and Nephotettix nigropictus, had consistently higher post-fallow densities than pre-fallow densities. 5. At both sites, fallowing did not affect rice-invertebrate faunas differently between seasons with regard to community structure, trajectories and accumulation rates of guild members. 6. Synthesis and applications. In tropical irrigated rice fields, small-scale synchronous fallowing combined with low-pesticide inputs and pest-resistant rice varieties did not induce pest outbreaks or notably diminish populations of natural enemies when embedded in asynchronous cropping on larger, regional scales. Our results suggest that small-scale... [ABSTRACT FROM AUTHOR]

Rainfed wetland rice (RWR) had more species in common with irrigated wetland than dryland rice agroecosystems. Across ecosystems, higher pest densities and losses were recorded in RWR sites. We hypothesise that under low pressure from natural enemies, vegetative stage losses became particularly high due the combination of whorl maggot and caseworm damage combined with the physiological stress of transplanting shock. Both of these pest groups benefited from an expanded vegetative period common in RWR agroecosystems. Losses in older rice were probably due to stemborers. RWR is more prone to an array of physiological stresses than irrigated rice that we believe minimises crop compensation to accentuate insect losses. Chemical control is uneconomical mainly due to the low yield potential of RWR and the poor efficacy of applied insecticide. [ABSTRACT FROM AUTHOR]

In the Philippines most of the dryland rice pests are distinct from those of wetland culture. Partitioned-growth-stage yield loss studies revealed the highest losses in dryland rice were due to sown-seed and seedling pests (ants, field crickets, mole crickets, and termites) as well as root feeders (white grubs and root aphids) and early seedling pests (seedling maggot and flea beetle) more than the common foliar wetland pests. Losses (5-71%) were highest in the sites with the smallest rice area in which pests were concentrated and the poorest soils (which constrain yield compensation) along a continuum of dryland rice habitats. Crop management practices such as overseeding and fertility management can mitigate potential losses to a large degree. Therefore integrated crop management plays a central role in integrated pest management in dryland rice cultivation where the use of insecticides should be minimized for economic and environmental reasons. [ABSTRACT FROM AUTHOR]

Beneficial arthropods were monitored in monthly plantings over 4 years in a rainfed, triple-maize cropping system in southern Mindanao, Philippines. Generalist predators and two egg parasitoids of the Asian corn borer Ostrinia furnacalis (Guenée) (ACB) did not show significant differences in abundance with respect to calendar month of planting over 39 crops. Two species of Trichogramma (T. evanescens Westwood and T. chilonis Ishii) collectively parasitized 67% of ACB egg masses and 58% eggs over the study becoming more abundant as the crop aged. The closeness of the two parasitism rates suggests that to increase parasitoid efficacy, particularly early in the crop, the best strategy would be augmentation and to increase longevity of wasps by providing carbohydrate sources to extend their searching time. Unparasitized egg masses tended to be smaller showing they were more likely to be overlooked. The ratio between the two parasitoids was 56:44 in favour of the former. Trichogramma evanescens had been introduced 2 years earlier by a government project, whereas T. chilonis probably was introduced by sugarcane estates. Prior to their introduction there were no ACB egg parasitoids in the Philippines and both are firmly established as annual parasitism levels did not continue to rise during the study. Parasitoid activity caused significant reductions in neonate ACB larval numbers beginning 7 weeks after crop emergence in an average crop. Egg parasitism rates were positively and linearly correlated with ACB egg mass density. A quadratic regression model was established between mean egg parasitism rates and egg masses size with peak parasitism rates occurring at 25 eggs per mass. Collectively 32 species of generalist predators averaged 0.9 - 1.5 individuals per plant based on weekly samplings. If ants were excluded, the average dropped to 0.1 - 0.3 per plant. Ants, dominated by Solenopsis geminata (F.), fed on ACB eggs and larvae. Coccinellids as the next most numerous were represented by three species where Micraspis crocea (Mulsant) in particular tracked ACB egg masses and probably the corn leaf aphid Rhopalosiphum maidis (Fitch) as well. Four species of orthropterans also tracked ACB egg masses. The third most abundant guild was 17 spiders with the oxyopid Oxyopes javanus Thorell and the araneid Araneus inustus (C.L. Koch) highly correlated with ACB egg mass densities. Other spiders targeted ACB moths and Atherigona oryzae Malloch adults. The predatory mirid Cyrtorhinus lividipennis Reuter probably targeted the corn leafhopper Cicadulina bimaculata (Evans) and possibly thrips Thrips palmi Karny and Megalurothrips usitatus (Bagnall). The lacewing Chrysopa sp. was abundant late in the crop when aphids were present on tassels. [ABSTRACT FROM AUTHOR]

Monthly plantings conducted over 4 years in a rainfed triple maize cropping system in southern Mindanao, Philippines, revealed the Asian corn borer (ACB) Ostrinia furnacalis (Guenée) as the most important insect pest. Of minor importance and being restricted to one crop stage were rice seedling maggot Atherigona oryzae Malloch, thrips Thrips palmi Karny and Megalurothrips usitatus (Bagnall), corn leafhopper Cicadulina bimaculata (Evans), corn earworm Helicoverpa armigera (Hübner), and corn leaf aphid Rhopalosiphum maidis (Fitch). Farmers escape damage from ACB, seedling maggot, and thrips by planting the first crop in April. Planting of the second crop should be shifted from August to September to avoid ACB damage. Pest damage was low during the third crop, thus planting time is not an important consideration. Additional information on ACB bionomics was revealed in the study. Mean egg mass size was 36 eggs (range 1 - 169). Oviposition was found to be positively correlated with cumulative rainfall over the previous 3 - 8 weeks indicating that females seek healthy crops. Most (70%) oviposition occurred over a 4-week period in the 39 crops studied as a single peak between late-whorl through mid-tasseling stages when developing larvae would be more assured of feeding on the more nutritious pollen. The strong attraction of maize at early tasseling along with heavy parasitism in older maize become population synchronizing agents in the year round cropping study area, although less perfect than winters in temperate regions. Yield loss in southern Mindanao ranged from 20 to 49% which was more closely correlated with larval tunnels than moth exit holes. Correlations were significant only when damage was related to yield loss but not yield. [ABSTRACT FROM AUTHOR]

Biodiversity studies in ecology often begin with the fitting and documentation of sampling data. This study is conducted to make function approximation on sampling data and to document the sampling information using artificial neural network algorithms, based on the invertebrate data sampled in the irrigated rice field. Three types of sampling data, i.e., the curve species richness vs. the sample size, the curve rarefaction, and the curve mean abundance of newly sampled species vs.the sample size, are fitted and documented using BP (Backpropagation) network and RBF (Radial Basis Function) network. As the comparisons, The Arrhenius model, and rarefaction model, and power function are tested for their ability to fit these data. The results show that the BP network and RBF network fit the data better than these models with smaller errors. BP network and RBF network can fit non-linear functions (sampling data) with specified accuracy and don't require mathematical assumptions. In addition to the interpolation, BP network is used to extrapolate the functions and the asymptote of the sampling data can be drawn. BP network cost a longer time to train the network and the results are always less stable compared to the RBF network. RBF network require more neurons to fit functions and generally it may not be used to extrapolate the functions. The mathematical function for sampling data can be exactly fitted using artificial neural network algorithms by adjusting the desired accuracy and maximum iterations. The total numbers of functional species of invertebrates in the tropical irrigated rice field are extrapolated as 140 to 149 using trained BP network, which are similar to the observed richness. [ABSTRACT FROM AUTHOR]

Field data suggest that ants may be important predators of mantises which, in turn, may be important predators of jumping spiders (Salticidae). Using a tropical fauna from the Philippines as a case study, the reactions of mantises to ants, myrmecomorphic salticids (i.e. jumping spiders that resemble ants) and ordinary salticids (i.e. jumping spiders that do not resemble ants) were investigated in the laboratory. Three mantis species ( Loxomantis sp., Orthodera sp., and Statilia sp.) were tested with ten ant species, five species of Myrmarachne (i.e. myrmecomorphic salticids), and 23 ordinary salticid species. Two categories of the myrmecomorphic salticids were recognized: (1) ‘typical Myrmarachne’ (four species with a strong resemblance to ants) and (2) Myrmarachne bakeri (a species with less strong resemblance to ants). Ants readily killed mantises in the laboratory, confirming that, for the mantises studied, ants are dangerous. In alternate-day testing, the mantises routinely preyed on the ordinary salticids, but avoided ants. The mantises reacted to myrmecomorphic salticids similarly to how they reacted to ants (i.e. myrmecomorphic salticids appear to be, for mantises, Batesian mimics of ants). Although myrmecomorphic salticids were rarely eaten, M. bakeri was eaten more often than typical Myrmarachne. Because the mantises had no prior experience with ants, ant mimics or ordinary salticids, our findings suggest that mantises have an innate aversion to attacking ants and that this aversion is generalized to myrmecomorphic salticids even in the absence of prior experience with ants. © 2006 The Linnean Society of London, Biological Journal of the Linnean Society, 2006, 88, 23–32. [ABSTRACT FROM AUTHOR]

Balimau Putih [an Indonesian cultivar tolerant to rice tungro bacilliform virus (RTBV)] was crossed with IR64 (RTBV, susceptible variety) to produce the three filial generations F1, F2 and F3. Agroinoculation was used to introduce RTBV into the test plants. RTBV tolerance was based on the RTBV level in plants by analysis of coat protein using enzyme-linked immunosorbent assay. The level of RTBV in cv. Balimau Putih was significantly lower than that of IR64 and the susceptible control, Taichung Native 1. Mean RTBV levels of the F1, F2 and F3 populations were comparable with one another and with the average of the parents. Results indicate that there was no dominance and an additive gene action may control the expression of tolerance to RTBV. Tolerance based on the level of RTBV coat protein was highly heritable (0.67) as estimated using the mean values of F3 lines, suggesting that selection for tolerance to RTBV can be performed in the early selfing generations using the technique employed in this study. The RTBV level had a negative correlation with plant height, but positive relationship with disease index value. [ABSTRACT FROM AUTHOR]

The rice white stemborer (WSB) Scirpophaga innotata (Walker) supplanted the closely related rice yellow stemborer (YSB) S. incertulas (Walker) in irrigated, double-rice culture in both Koronadal, South Cotabato, Philippines and Java, Indonesia. In Java, WSB became a serious pest but not in Koronadal where damage levels remained unchanged. The species shift and subsequent outbreaks are seen as independent events. The former occurred just after the El Niño droughts in 1982 – 1983 which suggests that climatic factors triggered the demise of YSB which does not aestivate. A contributing factor may have also been the crop failures from pest outbreaks that occurred during the same period creating long fallows which would have allowed WSB larvae selectively to survive. WSB larvae have been known to diapause for up to 10 – 12 months and consequently is able to survive climatically driven long fallows. Diapause is terminated by rainfall >10 mm after larvae have rested for a minimum of 4 months. Supportive evidence in favour of climate as the causal agent of change is that the distribution of WSB in Asia and Oceania overlaps that of the Intertropical Convergence Zone of the Southern Oscillation. YSB on the other hand is more adapted to a monsoon climate. It is also hypothesised that WSB, normally associated with single-crop, rainfed-rice culture, was able to adapt to double-cropped, irrigated culture due to the introduction of early maturing rices. From what is known about rice stemborer ecology, five cultural practices and natural events were postulated as the reasons keeping WSB densities in check in Koronadal: (1) medium maturing varieties to reduce the dry season fallow, (2) low inorganic N levels, (3) natural enemies, (4) destruction of crop residue harbouring larvae and pupae during land preparation, and (5) rainfall in the dry season causing suicide flights. Control strategies for areas where WSB is a pest should be based on: (1) reducing the fallow period by growing longer maturing varieties and (2) undertaking early ploughing for the wet season crop. [ABSTRACT FROM AUTHOR]

Although the rice white stemborer (WSB) Scirpophaga innotata (Walker) has been an epidemic pest in other locations in the Philippines and Indonesia, its population has remained at chronic pest levels in Koronadal, southern Mindanao, Philippines. Field studies were undertaken to determine the role of egg parasitoids and general predators in suppressing WSB numbers. The results revealed greater mortality levels on WSB than in any other location where beneficials have been assessed. Four hymenopteran parasitoids ( Tetrasticus schoenobii Ferriere [Eulophidae], Telenomus rowani (Gahan) [Scelionidae], Telenomus dignus (Gahan), and Trichogramma japonicum Ashmead [Trichogrammatidae]) combined to parasitise 65% of eggs in the second 1990 – 1991 rice crop. Multiple parasitism occurred in 61% of parasitised egg masses. Egg predation averaged 44% principally by the tettigoniids Conocephalus longipennis (de Haan) and C. maculatus (Leth.). Generalist predators steadily built up over the rice crop. A contributing factor to the high success of natural enemies could be related to the special situation of two irrigation systems interspersed among each other. Communal systems fed by artesian wells resulted in asynchronous planting areas where farmers can plant five crops in 2 years juxtaposed to a larger river diversion system typified by highly synchronous double rice cropping. The heterogeneous habitat created by the two irrigation systems could favour the density-dependent T. schoenobii , the keystone parasitoid in the rice ecosystem, which acts as both a parasitoid and predator. [ABSTRACT FROM AUTHOR]

Rice seedling maggot Atherigona oryzae Malloch is a minor pest of upland rice Oryza sativa L. and maize Zea mays L. in the Philippines. Two cultural control methods, early planting and overseeding, were evaluated separately on upland rice in an eroded, high rainfall area in Northern Mindanao. Farmers plant maize ahead of upland rice in separate fields with the onset of the rainy season. Regression analysis from data over six seasons showed on average the first 50% of farmers who planted ahead of their neighbours suffered damage significantly below the 5% deadheart action threshold. When early rice planting relative to one's neighbours was combined with earliness with regard to sowing maize, damage was further reduced. Useful methods for forecasting deadhead incidence 1-2 months ahead of rice planting were developed. The deadheart incidence rate was highly correlated with the amount of rain that fell in February and March as well as with the number of adults collected from bait traps in March or April. Six seeding rates were compared in 20-kg increments from 50 to 150 kg/ha with and without insecticide seed treatment. There was no significant yield response over the seeding rates tested when protected by insecticide, but when untreated, the highest yield occurred at 120 kg seed/ha and the greatest return at 90 kg/ha. Yields declined above the 120 kg/ha level from interplant competition Rice seedling maggot egg density decreased but the deadheart incidence rate increased with increasing plant densities, both linearly. Perhaps higher plant densities led to greater larval survival and dispersal. Planting rice early is dependent on early maize planting. Planting maize early and following maize within the generation period of rice seedling maggot with rice sown from 90 to 120 kg/ha would be particularly beneficial in years when the rice seedling maggot is predicted to be a high risk. [ABSTRACT FROM AUTHOR]

Soil sampling over a two-year period in Claveria, Northern Mindanao, Philippines, revealed the presence of five white grub species (Coleoptera: Scarabaeidae) in the deforested, infertile, and highly eroded grassland environment being converted to small farms. Population dynamics data point to Leucopholis irrorata (Chevrolat), Holotrichia mindanaoana Brenske, and H. flachi Brenske being biennial with Adoretus luridus Blanchard and Anomala humeralis Burmeister being annual species. The three biennial species are synchronized to even-numbered years. Small subpopulations of the biennial species show evidence of annual or allochronic cycles. L. irrorata has an annual cycle in other areas of the Philippines on sugarcane but takes two years to develop in Claveria probably due to infertile soils and a longer feeding period. Other subpopulations of young larvae and emerged adults occurring in the late rainy season were 'attempts' at multiple generations or delayed development, but were considered suicidal due to the impending dry season. Synchronization of life stages occurs with pupation and adult emergence with early rains. Habitat preferences of the five species were elucidated by topography, cultivation, and presence of trees. L. irrorata and H. mindanaoana adults were found in 30 flight trees. Most (81%) of the larval stages were found within the top 20 cm of soil but some dug to 70 cm depth. Peak third instar larval densities reached 25.5/m[sup 2] for all five species combined, but due to the biennial cycles of the major species, white grubs present economic importance to upland rice and maize only in odd numbered years. Control efforts are most economically directed during even numbered years giving a two-year benefit in population reduction. [ABSTRACT FROM AUTHOR]

Experiments were conducted to determine the extent to which populations of Bradyrhizobium sp. strain Tal 209SR were suppressed by the antagonistic activity of a Streptomyces sp. isolated from a highly weathered tropical soil. The activity of the actinomycete was evaluated in culture medium in the presence or absence of clay minerals and in the soil from which the actinomycete was isolated after sterilization by gamma-irradiation. The presence of the actinomycete in culture medium was associated with a significant reduction in the density of Bradyrhizobium sp. (Tal 209SR). Nevertheless, the density of the Bradyrhizobium sp. surviving in the medium in the presence of the actinomycete was much higher than that normally observed when comparable densities of rhizobia are introduced into non-sterile soils. The presence of the antagonistic actinomycete in culture medium was associated with a drastic decrease in the optical density of the medium. This decrease was accompanied by a significant decrease in the insoluble exopolysaccharide content of the medium in addition to the significant decrease in bradyrhizobial cells. The actinomycete did not appear to significantly influence the growth and survival of the test Bradyrhizobium sp. in sterile soil. The inability of the actinomycete to significantly antagonize the test bacterium in sterile soil was not adequately explained by the presence of clay minerals. [ABSTRACT FROM AUTHOR]

Evaluates the effects of insecticide spraying on insect pest population dynamics in a rice ecosystem in the Philippines. Cofana spectra; Sogatella furcifera; Recilia dorsalis; Natural enemies; Population fluctuations.

In Los Baños in the Philippines (Laguna, Luzon), Scytodes sp. indet. is a web-building spitting spider (Scytodidae) that preys primarily on jumping spiders (Salticidae) and Portia labiata is an aggressive-mimic jumping spider that preys especially frequently on Scytodes. Tactics by which three species of Portia (P. africana , P. fimbriata , and P. labiata ) and, for Portia labiata , three disjunct populations (Sri Lanka and, in the Philippines, Sagada and Los Baños) capture this especially dangerous prey are compared. Local adaptation to Scytodes by the Los Baños P. labiata is discussed. The Los Baños P. labiata uniquely made consistent use of tactics (soft plucking with palps and signal–detour–leap sequences) that were apparently responsible for greater prey-capture success and more effective avoidance of being spat on. Inter- and intraspecific differences were evident despite having used Portia that were reared in the laboratory with no prioir experience with scytodids. [ABSTRACT FROM AUTHOR]