Miracle-dz/UniFAR-FTUs huggingface dataset:
Phytophagous Insects as Regulators of Forest Primary Production

Phytophagous insects are common, ubiquitous elements of most terrestrial ecosystems. Occasionally some species become so abundant that they threaten the stability or output of systems having high ecological, esthetic, or economic value. Forest ecosystems, in particular, support myriads of phytophagous insects, but only few cause dramatic defoliations and widespread destruction of trees. These are termed outbreak species. Four such species currently are stirring public concern in North America: the Douglas fir tussock moth, the gypsy moth, the eastern spruce budworm, and the southern pine bark beetle. Normal insect grazing (from 5 to 30 percent of annual foliage crops) usually does not impair annual plant (primary) production. In fact, it may accelerate growth. Although outbreaks (either local or extensive) do reduce plant production temporarily, they commonly occur in individual plants or in whole forest systems that are not particularly productive-that is, those which are under stress resulting from inadequate or excessive moisture, nutrient deficiencies, or pollution, or are senescent, having already passed their peak efficiencies in biomass production. Moreover, after an outbreak has subsided, there is evidence that the residual vegetation is more productive than the vegetation that was growing immediately before the outbreak. For almost a century, research on phytophagous insects has focused primarily on aspects of their population biology and dynamics and their short-term impact on host plant growth and survival. Only recently has attention been directed at understanding and elucidating their long-term interactions with such fundamental ecosystem processes as primary production and
Cinética de degradação e fermentação ruminal da Brachiaria brizantha cv. marandu colhida em diferentes idades ao corte

Fermentation kinetics of Brachiaria brizantha cv Marandu harvested on 28, 56, 84, and 112 days of growth was evaluated with the semi-automatic in vitro gas production technique. Regression equations between volume of gas and dry-matter digestibility during fermentation periods of treatments were linear. Marandu grass harvested on 28 and 56 days of growth showed the greatest rate of gas production around 18 hours of incubation, while the rate of gas production of forages cut at 84 and 112 days reached the peak at 36 hours of incubation. Cumulative gas production was higher on 28 and 56 days of harvest intervals than grass harvested on 84 and 112 days. Therefore, the best harvest stage for using Brachiaria brizantha cv Marandu were between 28 and 56 days due to highest ruminal fermentability.
Broad Scale Distribution of Ferns and Lycophytes along Environmental Gradients in Central and Northern Amazonia, Brazil

Establishing which factors determine species distributions is of major relevance for practical applications such as conservation planning. The Amazonian lowlands exhibit considerable internal heterogeneity that is not apparent in existing vegetation maps. We used ferns as a model group to study patterns in plant species distributions and community composition at regional and landscape scales. Fern species composition and environmental data were collected in 109 plots of 250 × 2 m distributed among four sites in Brazilian Amazonia. Interplot distances varied from 1 to ca 670 km. When floristically heterogeneous datasets were analyzed, the use of an extended Sørensen dissimilarity index rather than the traditional Sørensen index improved model fit and made interpretation of the results easier. Major factors associated with species composition varied among sites, difference in cation concentration was a strong predictor of floristic dissimilarity in those sites with pronounced heterogeneity in cation concentration. Difference in clay content was the most relevant variable in sites with uniform cation concentrations. In every case, environmental differences were invariably better than geographic distances in predicting species compositional differences. Our results are consistent with the ideas that: (1) the relative predictive capacity of the explanatory variables depend on the relative lengths of the observed gradients; and (2) environmental gradients can be hierarchically structured such that gradients occur inside gradients. Therefore, site‐specific relationships among variables can mask the bigger picture and make it more difficult to unravel the factors structuring plant communities in Amazonia.
New Technology for Producing Paste-like Fish Products using Lactic Acid Bacteria Fermentation

: To develop a new processing technique, mackerel mince was homogenized to obtain different media with protein concentration of 90, 45, 22.5 mg/mL, respectively. Lactic acid bacteria (LAB) were inoculated to the media. During 48 h fermentation at 37 °C, rapid growth of LAB, decline in pH, suppression of main microflora, and increases in whiteness, Hunter L and sensory quality were observed and the VBN of fermented samples was still below 25 mg/100g. After 24 and 48 h fermentation, the sensory evaluation and photographic records indicated the high acceptability of the fermented products. From this study, various LAB fermented fish products can be produced and this technique has very high commercial potential.
Characterization of esterases from abamectin-resistant and susceptible strains of Tetranychus urticae Koch (Acari: Tetranychidae)

ABSTRACT In this study the esterases involved in abamectin resistance have been characterized from the two-spotted spider mite, Tetranychus urticae Koch. The resistant strain of T. urticae showed ≥ 3000-fold resistance to abamectin compared with the susceptible strain. Enzyme assays revealed that esterase activity in the resistant strain was 2.14-fold and 1.33-fold higher than that of the susceptible strain when α-naphthyl acetate (α-NA) or α-naphthyl propionate (α-NP) was used as substrate, respectively. In contrast, there was no significant difference in the enzyme activity among the resistant and susceptible strains when β-naphthyl acetate (β-NA) or α-naphthyl butyrate (α-NB) were used as substrate. Km and Vmax values of the resistant strain to α-NA were 1.43 and 1.68 times lower and higher than that of susceptible strain, respectively. The results showed a significant difference in the esterase patterns and abamectin and rosemary essential oil showed a potent inhibitory effect on esterase in resistant and susceptible strains. The optimum temperature (30°C) and optimum pH (pH 6.5) for relative activity of esterase for both strains is the same. The effects of different concentrations of several reagents on the relative activity were also investigated.
Effects of Nutrient Availability and Herbivory on Polyphenolics in the Seaweed Fucus Versiculosus

Research seeking to explain intraspecific variations in plant phenolics has focused on two general paradigms, the resource availability (carbon/nutrient balance) and induced-defense models. We experimentally tested both hypotheses to explain changes in phlorotannin concentrations in the brown alga Fucus vesiculosus. Fucus was collected monthly from two estuarine sites (Cape Cod, Massachusetts, USA) differing in nitrogen availability, and analyzed for polyphenolic levels and tissue-nitrogen concentrations. In situ nutrient enrichment experiments were conducted to measure changes in polyphenolic levels related to N availability. Simulated grazing experiments examined the possibility of induced increases in polyphenolic concentrations in Fucus vesiculosus. Paired choice ex- periments conducted in the laboratory examined feeding selectivity by the snail Littorina littorea for either Fucus population. Field measurements and experiments revealed temporal and site-related changes in tissue constituents. Polyphenolic concentrations were consistently, sometimes two times, higher in Fucus vesiculosus from the low-N site compared with algae from the high-N site; tissue-N content was higher in the population from the high-N site. For both populations, tissue N was inversely correlated with polyphenolic concentrations. Only Fucus from the low-N site showed a significant reduction in polyphenolic concentrations under experi- mental enrichment. Regression analysis revealed a significant inverse relationship (R2 = 0.71) between phenolic concentrations and growth rates for Fucus at the high-N, but not the low-N site. This suggests a growth cost associated with phlorotannin production for this phenolic-poor population due, perhaps, to C-limited growth. Phlorotannin concentra- tions increased significantly in clipped Fucus at the low-N site in two of three simulated grazing experiments, indicating an inducible response. We did not find a significant in- ducible response for the high-N, phenolic-poor population, and our choice experiments revealed a clear preference for this population by Littorina littorea. Our results offer support for both the induced-defense and carbon/nutrient balance hypotheses as explanation for variations in phlorotannin concentrations in Fucus vesiculosus. We suggest that within- species variation in polyphenolics is due to a complex interaction of environmental (nutrient availability, irradiance levels) and defense-related (grazing activity) factors.
Time‐to‐kill: measuring attack rates in a heterogenous landscape with multiple prey types

Although spatial heterogeneity of prey and landscapes are known to contribute to variation around predator-prey functional response models, few studies have quantified these effects. We illustrate a new approach using data from winter movement paths of GPS-collared wolves in the Rocky Mountains of Canada and time-to-event models with competing risks for measuring the effect of prey and landscape characteristics on the time-to-kill, which is the reciprocal of attack rate (aN) in a Holling's functional response. We evaluated 13 a priori models representing hypothesized mechanisms influencing attack rates in a heterogeneous landscape with two prey types. Models ranged from variants on Holling's disc equation, including search rate and prey density, to a full model including prey density and patchiness, search rates, satiation, and landscape features, which were measured along the wolf's movement path. Movement rates of wolves while searching explained more of the variation in time-to-kill than prey densities. Wolves did not compensate for low prey density by increasing movement rates and there was little evidence that spatial aggregation of prey influenced attack rates in this multi-prey system. The top model for predicting time-to-kill included only search rate and landscape features. Wolves killed prey more quickly in flat terrain, likely due to increased vulnerability from accumulated snow, whereas attack rates were lower when wolves hunted near human-made features presumably due to human disturbance. Understanding the sources of variation in attack rates provides refinements to functional response models that can lead to more effective predator–prey management in human-dominated landscapes.
Mechanistic model of intake of tropical pasture, depending on the growth and morphology of forage at a vegetative stage

The present model is targeted to simulate the diet of animals in tropical pastures, starting from underlying measurements carried out at the level of the tiller. Practically, we used measurements carried out at the following two levels: (1) on many tillers identified in the sward with rings and measured in various conditions (stages of regrowth, more or less fertilised and or irrigated), (2) on plots grazed individually by heifers tethered during 24 h, with measurements of both the forage and the animal faeces, for assessing their diet. The first step consisted in building a mechanistic model of the morphological grass growth calibrated on measurements performed on Dichanthium spp. at five vegetative stages of growth. In the process of growth, the principal stem was the major driving force, and the senescence of leaves was followed by their disappearance. The compartments represent lengths of stem or leaves. Taking into account the diversity of kinetics of the leaf appearance and growth, they were pooled in three types, according to their appearance process (two lower leaves, four leaves in the middle and the others at the upper level). In a second step, the impact of animal bites was included as an auxiliary variable in the model, taking into account the information at the level of the tillers and at the plot level. The impact of animal depends on the characteristics of the tiller, the length (or mass) and of the leaf characteristics, e.g. the leaves fraction in the sward. Afterwards, the information obtained at the tiller level and from the plot was compared. With a bottom-up approach it is possible to predict at a daily scale, starting from the tiller measurements, the dry matter intake and the organic matter digestibility, both measured at the plot level. Conversely, in a top-down approach, the information measured at the plot level were useful for adjusting the information acquired at the level of the tillers, e.g. the estimates of organic matter digestibility of the stems and the leaves at the plot level, allowing to assess the factors of variation of the organic matter digestibility of the consumed parts of a tiller, by the animal. These first results are encouraging and this model seems to promise a more complete mechanistic model of grazing cattle in tropical environment.
Pathogenicity of Meloidogyne javanica and Rhizoctonia solani Alone and in Combination on Soybean in Three Different Soil Classes of Eastern Nigeria

ABSTRACT Soybean cultivar, Samsoy-1 was exposed to Meloidogyne javanica and Rhizoctonia solani in three soil classes of eastern Nigeria. The soil classes included Lithosol (Maku soil), Hydromorphic soil (Abakaliki soil) and Young soils derived from recently deposited materials (Anam soil). Infection of the soybean varied in these soils. While no nematode infection occurred in Hydromorphic Abakaliki soil, severe and scanty infections were obtained in Lithosol and Young soils derived from recently deposited material (Anam soil). The fungus, however, caused moderate and slight infections in Lithosol and Hydromorphic Abakaliki soils, respectively. Under concomitant infection, the activity of R. solani on the soybean was increased in Lithosol.
Integrated shrimp‐mangrove farming systems in the Mekong delta of Vietnam

In recent years, mangroves have been seriously threatened by shrimp culture development in the Mekong delta of Vietnam. As one way of protecting the mangroves, efforts have been made to develop shrimp-mangrove integrated farming systems through State Forestry Fisheries Enterprises (SFFEs), involving a participatory approach. The present study investigated the shrimp-mangrove farming systems in Ngoc Hien district at the southern tip of the Mekong delta through a detailed farm-level survey, including technical, environmental, social and economic factors. A total of 161 shrimp-mangrove farms on the east and west coasts of Ngoc Hien district were surveyed. The results showed that on the East coast of the delta, the pH of the bottom soil, the water alkalinity, gate width ratio (ratio of gate width to pond area), pond age and mangrove density, and flooding level of ‘flat’ (flat is where the mangroves are planted) in the dry and rainy seasons were significantly correlated with shrimp pond yields. On the west coast, the pH of the bottom soil, dissolved inorganic phosphorus, ditch area, and flooding level of ‘flat’ were found to be significantly correlated with shrimp pond yields. An economic analysis, based solely on the economic returns from shrimp culture showed that the farming systems with a mangrove coverage of 30-50% of the pond area gave the highest annual economic returns. The results demonstrate a better economic return to farmers who maintain mangroves in their farming systems.
Population Dynamics of Limnetic Cladocera in a Beaver Pond

In a small, shallow, predation free beaver pond near Georgian Bay, Ontario Ceriodaphnia quadrangula was monacmic and Daphnia ambigua and Bosmina longirostris triacmic. Each species peaked and declined rapidly, presumably overshooting the carrying capacity of a food limited environment. Embryonic development times of each species at different temperatures was determined in the laboratory and fitted with Bĕlahradek’s function. Calculated instantaneous rates of birth and death were normal for D. ambigua and C. quadrangula but too low to account for the rapid fluctuations in numbers of B. longirostris, suggesting occasional gross sampling errors. Bosmina longirostris may periodically abandon the limnoplankton for a benthic existence thus avoiding capture.
Changes in vegetation composition and plant diversity with rangeland degradation in the alpine region of Qinghai-Tibet Plateau

The changes in vegetation composition and plant diversity of three different alpine ecosystems: alpine meadow, alpine steppe and alpine desert, impacted by different levels of degradation (healthy, lightly degraded and moderately degraded) were examined across a large-scale transect on the Qinghai-Tibet Plateau. The alpine meadow was dominated by sedges, the alpine steppe was dominated by grasses and the alpine desert was dominated by shrubs. The alpine meadow had the highest species diversity, whereas the alpine steppe had the lowest and tended to be dominated by a few species. Forbs were the dominant and most diverse functional group in the alpine meadow and the alpine steppe, which was different from the alpine desert. The importance values of the dominant species and levels of diversity measured by various vegetation indices were only slightly different in the degraded sites as compared with the non-degraded alpine meadow and steppe, whereas the alpine desert showed large changes in the composition and diversity of the plant community in response to degradation. In conclusion, the plant composition of the alpine meadow and alpine steppe ecosystems was more stable and appeared more resistant to disturbance than that of the alpine desert ecosystem.
Effect of different budding methods and times on grafting success of walnut.

Vegetative propagation of walnut is difficult compared with that of other fruit and nut species. The present study assessed three methods of grafting (patch, shield, and chip) at various periods of walnut growth and with different timings of grafting in walnut. Early May was the best time for grafting, at which time the highest success rate was obtained by the patch method (96%), followed by chip-budding (75%), while shield-grafting showed the lowest efficiency (10%). Patch-grafting was also successful (75-80%) in early August and moderately successful in mid-June (51-55%), while the shield and chip methods had no success during these two times (0.00%). Patch-grafting was more efficient and also induced better callus formation and scion growth than the other two methods. The genotypes used did not affect grafting efficiency. The best results were obtained by patch-budding in both tested genotypes. The present findings show the potential value of patch-grafting in early May as a propagation method for walnut for establishment of guidelines for propagation.
Microbial fungicides in the control of plant diseases

As environmental and commercial requirements for new fungicides are increasingly demanding, antifungal compounds of microbial origin attract tremendous interest as a starting point in the development of environmentally sound agricultural fungicides. As seen in fenpiclonil, fludioxonil and synthetic derivatives of the strobilurins such as azoxystrobin and krexosim-methyl, this approach for the development of microbial fungicides has proven to be a promising and effective strategy for developing new fungicides. As a result, microbial metabolites face a revival as lead compounds. Recently, numerous antifungal compounds were discovered from diverse microbial sources using traditional activity-based screening techniques. These microbial compounds showed potent control efficacy against various plant diseases, including chronic diseases which are difficult to control with conventional synthetic fungicides. Advances in screening systems directed to specific targets of fungal metabolism have increased the opportunities to discover novel antifungal agents with selectivity over non-target organisms. Microbial metabolites have also been exploited as a source for non-fungicidal disease control agents that do not inhibit vegetative hyphal growth, but rather interfere specifically with the infection process of pathogenic fungi. The specificity of microbial fungicides is a highly preferred characteristic in terms of impacting the environment, where it is closely related to the occurrence of fungicide resistance. The most recently developed fungicides from microbial metabolites, the strobilurins, provide a cue for the high risk of resistance development of site-specific fungicides.
Missing Data Due to Culling of Pigs before Testing and the Effects on the Genetic Evaluation

Abstract The effects of culling of pigs before field performance testing was analysed using a stochastic simulation of a pig breeding unit with 100 sows and 15 boars. Ten years of data were generated for age at test (AGE) and sidefat thickness (FAT). Culling was performed at random (C-RAND), within litters (C-W/IN) or over litters (C-OVER), by deleting records according to the phenotypic value of AGE in the complete dataset. Genetic evaluations in the subsets of data were compared with the results in data with no culling (C-NO). For C-NO and C-RAND there was a good agreement between the true (TBVs) and predicted breeding values (PBVs) for both traits. In C-W/IN and C-OVER the PBVs were less favourable than the TBVs for AGE. C-OVER also showed a small effect on PBVs for FAT and on litter effects for AGE. Correlations between PBVs from models with or without a litter effect were . 94 for C-NO and C-OVER, . 97 for C-RAND and . 98 for C-W/IN in the case of AGE, whereas for FAT they were all above . 98.
Histopathology of leech, Austrobdella bilobata Ingram, infestation on the yellowfin bream, Acanthopagrus australis (Günther), in northern New South Wales

The histopathology of leech, Austrobdella bilobata, infestation on the upper palate and pelvic fin of the yellowfin bream, Acanthopagrus australis (Gunther), is described. The feeding site was often haemorrhagic and swelling surrounded the attachment site. Histological examination revealed massive cellular infiltration (predominantly lymphocyte and macrophage) in the submucosa beneath the feeding and attachment sites. The latter also had a complete erosion of the integument beneath the parasite. Localized proliferation of connective tissue fibres and zones of necrosis and oedema were present in some cases.
Amino Acid and Fatty Acid Composition of Tissues of the Dungeness Crab (Cancer magister)

Tissues of the Dungeness crab (Cancer magister Dana) were analyzed for content of total lipid, protein, amino acids, fatty acids, and glucosamine. Ovaries and hepatopancreas were the major lipid storage organs. Gonads (ovaries and testes) and skeletal muscle contained substantially more protein than the other tissues. All tissues except the exoskeleton had balanced amino acid compositions. The exoskeletal protein was deficient in arginine and lysine. Glucosamine was a prominent constituent of the exoskeleton and of the gills and the gastric apparatus. Palmitic, palmitoleic, oleic, eicosapentaenoic, and docosahexaenoic acids were the major fatty acids found in all tissues.