The prey-seeking behavior of three spiders (X1-Pirata subpiraticus, X2-Clubiona japonicola and X3-Tetragnatha japonica) for brown plant hopper (X4-Nilaparvata lugens) and rice spittle bug (X5-Cal-litettix versicolor) ...The prey-seeking behavior of three spiders (X1-Pirata subpiraticus, X2-Clubiona japonicola and X3-Tetragnatha japonica) for brown plant hopper (X4-Nilaparvata lugens) and rice spittle bug (X5-Cal-litettix versicolor) was investigated, as well as how interference between and within species occurred, by using a quadratic regression rotational composite design. Six predation models derived from the analysis of interactions among and within predators and preys were developed. The total predatory capacity of spiders on rice insect pests after coexistence for one day can be expressed as follows: Y3 = 32.795 + 2.25X1 + 1.083X2 + 0.5X3 + 10.167X4 + 3.167X5 - 1.67X12 - 2.42X22 - 3.295X32 - 0.045X42 + 0.455X52 - 3.125X1X2 + 0.375X1X3 -0.625X1X4 - 0.375X1X5 + 0.375X2X3 - 0.875X2X4 + 0.125X2X5 + 0.375X3X4 - 0.375X3X5 + 0.125X4X5. The principal efficiency analysis using this model indicated that increases in insect pest density significantly increased predation by predators; this was much greater than the effect of any single predator. X4 had a greater effect than X5; however, X4 and X5 demonstrated little interspecific interference and even promoted each other and increased predation rates as the densities of the two pests increased. Among the three predators, an increase in the density of X, had the greatest effect on the increase in predation, X3 had the second, X2 the third greatest effect. As predator density increased inter- and intra-species interference occurred, which were largely related to the size, activity, niche breadth, niche overlap and searching efficiency of the predators. X2 produced the greatest interference between different individuals and between any other predator species. X3 had the second greatest, which reduced predation levels at high predator densities. Because of these factors, the highest predation rate was obtained at a prey density of 120 per 4 rice-hills. The optimal proportion of the three predators in the multi-predator prey system was X1: X2: X3 = 5.6:1.3:4.1.展开更多
This paper presents and compares four mathematical models with unique spatial effects for a prey-predator system, with Tetranychus urticae as prey and Phytoseiulus persimilis as predator. Tetranychus urticae, also kno...This paper presents and compares four mathematical models with unique spatial effects for a prey-predator system, with Tetranychus urticae as prey and Phytoseiulus persimilis as predator. Tetranychus urticae, also known as two-spotted spider mite, is a harmful plant-feeding pest that causes damage to over 300 species of plants. Its predator, Phytoseiulus persimilis, a mite in the Family Phytoseiidae, effectively controls spider mite populations. In this study, we compared four mathematical models using a numerical simulation. These models include two known models: self-diffusion, and cross-diffusion, and two new models: chemotaxis effect model, and integro diffusion model, all with a Beddington-De Angelis functional response. The modeling results were validated by fitting experimental data. Results demonstrate that interaction scheme plays an important role in the prey-predator system and that the cross-diffusion model fits the real system best. The main contribution of this paper is in the two new models developed, as well as the validation of all the models using experimental data.展开更多
Spider mites are significant pests in agricultural production.The increasing resistance of spider mites,along with environmental pollution and ecological imbalance caused by their control,is primarily attributed to th...Spider mites are significant pests in agricultural production.The increasing resistance of spider mites,along with environmental pollution and ecological imbalance caused by their control,is primarily attributed to the long-term use of chemical acaricides in agriculture.In contrast,bioactive substances of biological origin offer advantages such as wide availability,environmental friendliness,and low tendency to induce resistance,making them a research hotspot for spider mite control.This review summarizes recent advances in the use of plant-derived active compounds(exemplified by extracts from Veratrum rhizomes),RNA interference(RNAi)technology,and microorganism-derived active substances for controlling spider mites.These bioactive agents exert acaricidal effects by disrupting the nervous system,interfering with metabolic processes,or silencing key genes in mites,demonstrating favorable efficacy and considerable potential for development.However,challenges remain,including poor environmental stability,slow action,high production costs,and insufficient understanding of their effects on non-target organisms.Therefore,future research should focus on the screening and development of novel bioactive substances of biological origin,elucidation of their mechanisms of action,optimization of formulation technologies,and assessment of their ecological safety.These efforts will provide valuable insights for promoting the advancement of bioactive substances and supporting sustainable agricultural development.展开更多
Shanghai Disney Resort broke ground on a new Spider⁃Man⁃themed land,a major expansion that represents a rising global investment interest in Chinas theme park sector.Located close to Zootopia,the new land includes the...Shanghai Disney Resort broke ground on a new Spider⁃Man⁃themed land,a major expansion that represents a rising global investment interest in Chinas theme park sector.Located close to Zootopia,the new land includes the parks first major Marvel⁃themed attraction-a high⁃energy thrill roller coaster featuring Spider⁃Man,one of the most popular Marvel superheroes,according to the company.展开更多
Soil spiders were pitfall-trapped once every month in three forest vegetation types of Ziwuling natural secondary forest region, Gansu Province from April to October, 2004. A total of 2 164 spiders were collected, bel...Soil spiders were pitfall-trapped once every month in three forest vegetation types of Ziwuling natural secondary forest region, Gansu Province from April to October, 2004. A total of 2 164 spiders were collected, belonging to 43 species in 19 families, captured in 630 pitfall trap collections. Linyphiidae, Gnaphosidae and Lycosodae were found to be the dominant families in all habitat types, and the composition of soil spider assemblages was different between the three habitats. Ecological indices of diversity, richness and evenness were significantly different between the three habitats （ P 〈 0.05）. The relative abundance of guilds （based on numbers of individuals） varied greatly （P 〈 0.01）, which may releet resource availability within habitat types. The existence of different patterns within the assemblages reflects the importance of maintaining habitat heterogeneity and vegetation types in order to preserve soil spider biodiversity.展开更多
Hainantoxin-II （HnTx-II）, a novel neurotoxin, was isolated from the venom of the Chinese bird spider （Haplopelma hainanum） by cation exchange chromatography and reverse-phase HPLC. The toxin was a single chain pol...Hainantoxin-II （HnTx-II）, a novel neurotoxin, was isolated from the venom of the Chinese bird spider （Haplopelma hainanum） by cation exchange chromatography and reverse-phase HPLC. The toxin was a single chain polypeptide with calculated molecular weight of 4 253.135 obtained by mass spectrometry. The complete amino acid sequence of HnTx-II was determined by Edman degradation and found to contain 37 residues with three disulfide bonds. Results showed HnTx-II can reversibly paralyze cockroaches for several hours after intra-abdominal injection with ED50 of 16 μg/g and kill the insects immediately at a dose of 60 μg/g. It was also shown to kill mice at a LD50 value of 1.41μg/g after intracerebroventricular injection. Hainantoxin-II shares 91% sequence homology with Huwentoxin-II （HwTx-II）, an insecticidal peptide from another bird spider （Haplopelma schmidti） with a unique scaffold. While HnTx-II and HwTx-II both exhibit toxic activities in insects and mammals, HnTx-II shows higher insecticidal activity and lower lethiferous activity of mammals than HwTx-II. These results help clarify structural-functional relationships of the polypeptide toxin.展开更多
Objective] Field and laboratory observation was conducted to investigate Clubiona corrugate. [Method] The trials investigated the bio-ecology and behavior of the spider C. corrugate. [Result] The spider overwintered w...Objective] Field and laboratory observation was conducted to investigate Clubiona corrugate. [Method] The trials investigated the bio-ecology and behavior of the spider C. corrugate. [Result] The spider overwintered with spiderlings, adults and instars turn into adults after 6-8 molts. It had 2-3 generations each year in Hunan, and it owned the character of overlapping of generation in paddies. The average duration of generations of C. corrugate was 158.2 days, and the survival days av-eraged 223.2 days. The female and male mated several times without cannibalistic behavior, average number of eggs female laid throughout its adult life was 371.5, and hatchability can get 85.4%. The sex ratio was 1∶1. Its capability of resistance to starvation and drought was strong. Through indoor observation, the spider can sur-vive 25-61 days under the condition of no water and food. [Conclusion] The behav-ior of C. corrugate was also recorded in detail, and female usual y has a strong a-bility to protect their egg-sacs and spiderlings. At present, the bio-ecology and be-havior of the spider C. corrugate had not been reported.展开更多
Immature embryos of rice varieties "Xiushui11" and "Chunjiang 11" precultured for 4d were infected and transformed by Agrobacterium tumefaciens strain EHA101/pExT7 (containing the spider insecticid...Immature embryos of rice varieties "Xiushui11" and "Chunjiang 11" precultured for 4d were infected and transformed by Agrobacterium tumefaciens strain EHA101/pExT7 (containing the spider insecticidal gene). The resistant cant were transferred onto the differentiation medium and plants were regenerated. The transformation frequency reached 56%-72% measured as numbers of Geneticin (G418)-resistant calli produced and 36%-60% measured as numbers of transgenic plants regenerated, respectively. PCR and Southern blot analysis of transgenic plants confirmed that the T-DNA had been integrated into the rice genome. Insect bioassays using T1 transgenic plants indicated that the mortality of the leaffolder (Cnaphalocrasis medinalis) after 7d of leaf feeding reached 38%-61% and the corrected mortality of the striped stem borer (Chilo suppressalis) after 7d of leaf feeding reached 16%-75%. The insect bioassay results demonstrated that the transgenic plants expressing the spider insecticidal protein conferred enhanced resistance to these pests.展开更多
The purpose of this study is to investigate total mercury （THg） distribution and its bioaccumulation up the soil-plant-grasshopperspider in the Huludao City, which is polluted seriously by chlor-alkali and zinc smel...The purpose of this study is to investigate total mercury （THg） distribution and its bioaccumulation up the soil-plant-grasshopperspider in the Huludao City, which is polluted seriously by chlor-alkali and zinc smelting industry in Northeast of China. Results indicated that average THg concentrations in soil, plant leaves, grasshopper Locusta migratoria manilensis and Acrida chinensis, and spider were 0.151, 0.119, 0.167 and 0.134 mg/kg, respectively. THg spatial distribution suggested that most of mercury came from the chlor-alkali plant and the two zinc smelteries. The highest mercury concentration was found in the wings among different grasshoppers’ organs. Although spiders are the predatory, THg concentrations in their bodies were not high, and only on the same level as in grasshoppers, which might be due to spiders’ special living habits. In the light of the mercury transportation at every stage of the soil-plant-grasshopper-spider food chain, the bioaccumulation factors were 0.03, 0.79–1.11 and 0.80–1.13 respectively. It suggested that mercury biomagnification up terrestrial food chains was not so large and obvious as it was in the aquatic food chain.展开更多
文摘The prey-seeking behavior of three spiders (X1-Pirata subpiraticus, X2-Clubiona japonicola and X3-Tetragnatha japonica) for brown plant hopper (X4-Nilaparvata lugens) and rice spittle bug (X5-Cal-litettix versicolor) was investigated, as well as how interference between and within species occurred, by using a quadratic regression rotational composite design. Six predation models derived from the analysis of interactions among and within predators and preys were developed. The total predatory capacity of spiders on rice insect pests after coexistence for one day can be expressed as follows: Y3 = 32.795 + 2.25X1 + 1.083X2 + 0.5X3 + 10.167X4 + 3.167X5 - 1.67X12 - 2.42X22 - 3.295X32 - 0.045X42 + 0.455X52 - 3.125X1X2 + 0.375X1X3 -0.625X1X4 - 0.375X1X5 + 0.375X2X3 - 0.875X2X4 + 0.125X2X5 + 0.375X3X4 - 0.375X3X5 + 0.125X4X5. The principal efficiency analysis using this model indicated that increases in insect pest density significantly increased predation by predators; this was much greater than the effect of any single predator. X4 had a greater effect than X5; however, X4 and X5 demonstrated little interspecific interference and even promoted each other and increased predation rates as the densities of the two pests increased. Among the three predators, an increase in the density of X, had the greatest effect on the increase in predation, X3 had the second, X2 the third greatest effect. As predator density increased inter- and intra-species interference occurred, which were largely related to the size, activity, niche breadth, niche overlap and searching efficiency of the predators. X2 produced the greatest interference between different individuals and between any other predator species. X3 had the second greatest, which reduced predation levels at high predator densities. Because of these factors, the highest predation rate was obtained at a prey density of 120 per 4 rice-hills. The optimal proportion of the three predators in the multi-predator prey system was X1: X2: X3 = 5.6:1.3:4.1.
文摘This paper presents and compares four mathematical models with unique spatial effects for a prey-predator system, with Tetranychus urticae as prey and Phytoseiulus persimilis as predator. Tetranychus urticae, also known as two-spotted spider mite, is a harmful plant-feeding pest that causes damage to over 300 species of plants. Its predator, Phytoseiulus persimilis, a mite in the Family Phytoseiidae, effectively controls spider mite populations. In this study, we compared four mathematical models using a numerical simulation. These models include two known models: self-diffusion, and cross-diffusion, and two new models: chemotaxis effect model, and integro diffusion model, all with a Beddington-De Angelis functional response. The modeling results were validated by fitting experimental data. Results demonstrate that interaction scheme plays an important role in the prey-predator system and that the cross-diffusion model fits the real system best. The main contribution of this paper is in the two new models developed, as well as the validation of all the models using experimental data.
文摘Spider mites are significant pests in agricultural production.The increasing resistance of spider mites,along with environmental pollution and ecological imbalance caused by their control,is primarily attributed to the long-term use of chemical acaricides in agriculture.In contrast,bioactive substances of biological origin offer advantages such as wide availability,environmental friendliness,and low tendency to induce resistance,making them a research hotspot for spider mite control.This review summarizes recent advances in the use of plant-derived active compounds(exemplified by extracts from Veratrum rhizomes),RNA interference(RNAi)technology,and microorganism-derived active substances for controlling spider mites.These bioactive agents exert acaricidal effects by disrupting the nervous system,interfering with metabolic processes,or silencing key genes in mites,demonstrating favorable efficacy and considerable potential for development.However,challenges remain,including poor environmental stability,slow action,high production costs,and insufficient understanding of their effects on non-target organisms.Therefore,future research should focus on the screening and development of novel bioactive substances of biological origin,elucidation of their mechanisms of action,optimization of formulation technologies,and assessment of their ecological safety.These efforts will provide valuable insights for promoting the advancement of bioactive substances and supporting sustainable agricultural development.
文摘Shanghai Disney Resort broke ground on a new Spider⁃Man⁃themed land,a major expansion that represents a rising global investment interest in Chinas theme park sector.Located close to Zootopia,the new land includes the parks first major Marvel⁃themed attraction-a high⁃energy thrill roller coaster featuring Spider⁃Man,one of the most popular Marvel superheroes,according to the company.
文摘Soil spiders were pitfall-trapped once every month in three forest vegetation types of Ziwuling natural secondary forest region, Gansu Province from April to October, 2004. A total of 2 164 spiders were collected, belonging to 43 species in 19 families, captured in 630 pitfall trap collections. Linyphiidae, Gnaphosidae and Lycosodae were found to be the dominant families in all habitat types, and the composition of soil spider assemblages was different between the three habitats. Ecological indices of diversity, richness and evenness were significantly different between the three habitats （ P 〈 0.05）. The relative abundance of guilds （based on numbers of individuals） varied greatly （P 〈 0.01）, which may releet resource availability within habitat types. The existence of different patterns within the assemblages reflects the importance of maintaining habitat heterogeneity and vegetation types in order to preserve soil spider biodiversity.
基金supported by the Research Project of the Education Department of Zhejiang Province, China (Y200805989)~~
文摘Hainantoxin-II （HnTx-II）, a novel neurotoxin, was isolated from the venom of the Chinese bird spider （Haplopelma hainanum） by cation exchange chromatography and reverse-phase HPLC. The toxin was a single chain polypeptide with calculated molecular weight of 4 253.135 obtained by mass spectrometry. The complete amino acid sequence of HnTx-II was determined by Edman degradation and found to contain 37 residues with three disulfide bonds. Results showed HnTx-II can reversibly paralyze cockroaches for several hours after intra-abdominal injection with ED50 of 16 μg/g and kill the insects immediately at a dose of 60 μg/g. It was also shown to kill mice at a LD50 value of 1.41μg/g after intracerebroventricular injection. Hainantoxin-II shares 91% sequence homology with Huwentoxin-II （HwTx-II）, an insecticidal peptide from another bird spider （Haplopelma schmidti） with a unique scaffold. While HnTx-II and HwTx-II both exhibit toxic activities in insects and mammals, HnTx-II shows higher insecticidal activity and lower lethiferous activity of mammals than HwTx-II. These results help clarify structural-functional relationships of the polypeptide toxin.
基金Supported by National Natural Science Foundation of China[31472017]National Natural Science Foundation of China[31272339]+1 种基金National Natural Science Foundation of China[31071943]Major Program of Department of Science and Technology of Hunan Province[2014FJ2003]~~
文摘Objective] Field and laboratory observation was conducted to investigate Clubiona corrugate. [Method] The trials investigated the bio-ecology and behavior of the spider C. corrugate. [Result] The spider overwintered with spiderlings, adults and instars turn into adults after 6-8 molts. It had 2-3 generations each year in Hunan, and it owned the character of overlapping of generation in paddies. The average duration of generations of C. corrugate was 158.2 days, and the survival days av-eraged 223.2 days. The female and male mated several times without cannibalistic behavior, average number of eggs female laid throughout its adult life was 371.5, and hatchability can get 85.4%. The sex ratio was 1∶1. Its capability of resistance to starvation and drought was strong. Through indoor observation, the spider can sur-vive 25-61 days under the condition of no water and food. [Conclusion] The behav-ior of C. corrugate was also recorded in detail, and female usual y has a strong a-bility to protect their egg-sacs and spiderlings. At present, the bio-ecology and be-havior of the spider C. corrugate had not been reported.
文摘Immature embryos of rice varieties "Xiushui11" and "Chunjiang 11" precultured for 4d were infected and transformed by Agrobacterium tumefaciens strain EHA101/pExT7 (containing the spider insecticidal gene). The resistant cant were transferred onto the differentiation medium and plants were regenerated. The transformation frequency reached 56%-72% measured as numbers of Geneticin (G418)-resistant calli produced and 36%-60% measured as numbers of transgenic plants regenerated, respectively. PCR and Southern blot analysis of transgenic plants confirmed that the T-DNA had been integrated into the rice genome. Insect bioassays using T1 transgenic plants indicated that the mortality of the leaffolder (Cnaphalocrasis medinalis) after 7d of leaf feeding reached 38%-61% and the corrected mortality of the striped stem borer (Chilo suppressalis) after 7d of leaf feeding reached 16%-75%. The insect bioassay results demonstrated that the transgenic plants expressing the spider insecticidal protein conferred enhanced resistance to these pests.
基金supported by the National Natural Science Foundation of China (No 40830535, 40803021)
文摘The purpose of this study is to investigate total mercury （THg） distribution and its bioaccumulation up the soil-plant-grasshopperspider in the Huludao City, which is polluted seriously by chlor-alkali and zinc smelting industry in Northeast of China. Results indicated that average THg concentrations in soil, plant leaves, grasshopper Locusta migratoria manilensis and Acrida chinensis, and spider were 0.151, 0.119, 0.167 and 0.134 mg/kg, respectively. THg spatial distribution suggested that most of mercury came from the chlor-alkali plant and the two zinc smelteries. The highest mercury concentration was found in the wings among different grasshoppers’ organs. Although spiders are the predatory, THg concentrations in their bodies were not high, and only on the same level as in grasshoppers, which might be due to spiders’ special living habits. In the light of the mercury transportation at every stage of the soil-plant-grasshopper-spider food chain, the bioaccumulation factors were 0.03, 0.79–1.11 and 0.80–1.13 respectively. It suggested that mercury biomagnification up terrestrial food chains was not so large and obvious as it was in the aquatic food chain.
