The two-spotted spider mite, Tetranychus urticae Koch (Tetranychidae), is considered one of the most important species of pest-mites because it is cosmopolite and polyphagous. This species has been described as attack...The two-spotted spider mite, Tetranychus urticae Koch (Tetranychidae), is considered one of the most important species of pest-mites because it is cosmopolite and polyphagous. This species has been described as attacking over 1,100 plant species in 140 families of economic importance. On the other hand, Phytoseiulus macropilis (Banks) (Phytoseiidae) is a predatory mite of group I, specialist as predatory mite from the Tetranychus genus. Thus, the objective of this work was to evaluate predatory potential of P. macropilis in its different stages—nymphs, female and male adults—preying on T. urticae also in different stages—eggs, larvae, nymphs, and adults—and to know the functional and numerical responses in lab studies. Both the experiments were carried out on arenas made of Jack-bean leaflets’ discs [Canavalia ensiformis (L.)—Fabaceae] with 3 cm in diameter over agar-water at 3% inside 5 cm in diameter uncapped Petri dishes. To know the predatory activity, forty T. urticae and one predatory mite were placed in each arena with the respective phases of the developmental life cycle to be evaluated. To know the potential of predation, the no killed mites were counted after 24 hours. To know the functional and numerical responses, immature T. urticae in densities of 1 to 300/arena were offered for P. macropilis. The results for the predatory potential showed that larvae and male adult of T. urticae were the most killed stages, and the female predatory mites were the one that consumed most prey. The functional response showed a positive and significant correlation, suggesting a type II functional response (convex), a cyrtoid curve rising at a decreasing rate to a plateau, where the consumption remains constant regardless of prey density.展开更多
The remaining phosphorus (Prem), P concentration that remains in solution after shaking soil with 0.01 mol L-1 CaCl2 containing 60μg mL-1 P, is a very useful index for studies related to the chemistry of variable cha...The remaining phosphorus (Prem), P concentration that remains in solution after shaking soil with 0.01 mol L-1 CaCl2 containing 60μg mL-1 P, is a very useful index for studies related to the chemistry of variable charge soils. Although the Prem determination is a simple procedure, the possibility of estimating accurate values of this index from easily and/or routinely determined soil properties can be very useful for practical purposes. The present research evaluated the Prem estimation through multiple regression analysis in which routinely determined soil chemical data, soil clay content and soil pH measured in 1 mol L-1 NaF (pHNaF) figured as Prem predictor variables. The Prem can be estimated with acceptable accuracy using the above-mentioned approach, and pHNaF not only substitutes for clay content as a predictor variable but also confers more accuracy to the Prem estimates.展开更多
Background： Recent technological advances in genomics have allowed the genotyping of cattle through single nucleotide polymorphism（SNP） panels. High-density SNP panels possess greater genome coverage and are useful...Background： Recent technological advances in genomics have allowed the genotyping of cattle through single nucleotide polymorphism（SNP） panels. High-density SNP panels possess greater genome coverage and are useful for the identification of conserved regions of the genome due to selection, known as selection signatures（SS）. The SS are detectable by different methods, such as the extended haplotype homozygosity（EHH）; and the integrated haplotype score（i HS）, which is derived from the EHH. The aim of this study was to identify SS regions in Canchim cattle（composite breed）, genotyped with high-density SNP panel.Results： A total of 687,655 SNP markers and 396 samples remained for SS analysis after the genotype quality control. The i HS statistic for each marker was transformed into pi HS for better interpretation of the results.Chromosomes BTA5 and BTA14 showed pi HS 〉 5, with 39 and nine statistically significant SNPs（P 〈 0.00001）,respectively. For the candidate selection regions, i HS values were computed across the genome and averaged within non-overlapping windows of 500 Kb. We have identified genes that play an important role in metabolism,melanin biosynthesis（pigmentation）, and embryonic and bone development.Conclusions： The observation of SS indicates that the selection processes performed in Canchim, as well as in the founder breeds（i.e. Charolais）, are maintaining specific genomic regions, particularly on BTA5 and BTA14. These selection signatures regions could be associated with Canchim characterization.展开更多
The use of biochar can have several effects on plant germination,depending on raw material,preparation method and application dose.However,the molecular mechanisms that lead to those results have yet to be elucidated....The use of biochar can have several effects on plant germination,depending on raw material,preparation method and application dose.However,the molecular mechanisms that lead to those results have yet to be elucidated.The aim of this research was to improve the understanding of these mechanisms by characterizing the metabolic effects of sugarcane bagasse biochar on soybean germination.Three types of biochars were prepared by pyrolysis at 300℃(SCB300),400℃(SCB400)and 600℃(SCB600).Then,each one was mixed into sand at 1%,3%,5%(w/w)dose,respectively.The experiment was performed in 8 days of incubation,when the number of germinated seeds and the average radicle length were determined.To evaluate the metabolome,the dry biomass(DB)was subjected to extraction with a mixture of methanol-d4 and D2O(1:1 v/v).The extracts were submitted to metabolomics analysis by Proton Nuclear Magnetic Resonance.The Relative Germination,Relative Average Radicle Growth and Germination Index increased in all treatments compared to control.On the other hand,the DB increased in all treatments,except for SCB300,at doses of 1%and 3%w/w.Seven metabolites(alanine,asparagine,acetic acid,citric acid,glycerol,fatty acids and sucrose)were identified and quantified in DB extracts as the most influential finding for the separation of treatments.Taken together,these results strongly suggested that biochars accelerated the catabolism of triacylglycerols to sucrose and induced a slight osmotic stress.展开更多
Background： Beef cattle breeding programs in Brazil have placed greater emphasis on the genomic study of reproductive traits of males and females due to their economic importance. In this study, genome-wide associati...Background： Beef cattle breeding programs in Brazil have placed greater emphasis on the genomic study of reproductive traits of males and females due to their economic importance. In this study, genome-wide associations were assessed for scrotal circumference at 210 d of age, scrotal circumference at 420 d of age, age at first calving, and age at second calving, in Canchim beef cattle. Data quality control was conducted resulting in 672,778 SNPs and 392 animals.Results： Associated SNPs were observed for scrotal circumference at 420 d of age（435 SNPs）, followed by scrotal circumference at 210 d of age（12 SNPs）, age at first calving（six SNPs）, and age at second calving（four SNPs）. We investigated whether significant SNPs were within genic or surrounding regions. Biological processes of genes were associated with immune system, multicellular organismal process, response to stimulus, apoptotic process, cellular component organization or biogenesis, biological adhesion, and reproduction.Conclusions： Few associations were observed for scrotal circumference at 210 d of age, age at first calving, and age at second calving, reinforcing their polygenic inheritance and the complexity of understanding the genetic architecture of reproductive traits. Finding many associations for scrotal circumference at 420 d of age in various regions of the Canchim genome also reveals the difficulty of targeting specific candidate genes that could act on fertility; nonetheless,the high linkage disequilibrium between loci herein estimated could aid to overcome this issue. Therefore, al relevant information about genomic regions influencing reproductive traits may contribute to target candidate genes for further investigation of causal mutations and aid in future genomic studies in Canchim cattle to improve the breeding program.展开更多
The species of mite Oligonychus ilicis (McGregor) (Tetranychidae) is an important pest of dicotyledonous plants, cosmopolitan and polyphagous, reported in seven countries from four continents, feeding on 34 plant spec...The species of mite Oligonychus ilicis (McGregor) (Tetranychidae) is an important pest of dicotyledonous plants, cosmopolitan and polyphagous, reported in seven countries from four continents, feeding on 34 plant species of 15 families. The spider mite O. ilicis is known in Brazil as coffee red spider mite, and as southern red mite most in other countries. In Brazil O. ilicis has been reported as the second most important pest of “Conillon” coffee, Coffea canephora Pierre & Froehner, in the state of Espírito Santo. Depending on the number of mites per leaf of arabica coffee, Coffea arabica L., the rate of potential photosynthesis can be reduced by 37% to 50%. In the present study, it was investigated the potential of the two predatory mites which, among others, naturally occurs in coffee plantations, Euseius alatus DeLeon and Amblyseius herbicolus (Chant) (Phytoseiidae), in the control of O. ilicis in coffee plants. It was used potted coffee plants in this research, with approximately 100 cm high, growing in a greenhouse covered with transparent plastic and shading material of 50% sun protection factor, and with fine mesh on all the sides. Results showed that both species of predatory mites, A. herbicolus and E. alatus, are efficient in reducing the mobile phases—larvae, protonymphs, deutonymphs and adults—of the southern red mite O. ilicis. So, the importance of conservation and increase number of these predatory mites in the field coffee growing is essential for implementing the southern red mite integrated management tactic, since these species are of natural occurrence in coffee plants.展开更多
A spectral method based on Hermite cubic splines expansions combined with a collocation scheme is used to develop a solution for the vector form integral S-model kinetic equation describing rarefied gas flows in cylin...A spectral method based on Hermite cubic splines expansions combined with a collocation scheme is used to develop a solution for the vector form integral S-model kinetic equation describing rarefied gas flows in cylindrical geometry. Some manipulations are made to facilitate the computational treatment of the singularities inherent to the kernel. Numerical results for the simulation of flows generated by pressure and thermal gradients, Poiseuille and thermal-creep problems, are presented.展开更多
Aims: Cabraleadiol (1), Ocotilone (2) and Odoratone (3) are three triterpenes isolated from Cabralea canjerana (Vell.) Mart. (Meliaceae). They were chemically characterized, and their effect was tested on the light re...Aims: Cabraleadiol (1), Ocotilone (2) and Odoratone (3) are three triterpenes isolated from Cabralea canjerana (Vell.) Mart. (Meliaceae). They were chemically characterized, and their effect was tested on the light reaction of photosynthesis. Study Design: Natural products were used as models to find new models for inhibitors of photosynthesis. Place and Duration of Study: Departmento de Química, Universidade Federal de São Carlos and Departmento de Bioquímica, Facultad de Química, Universidad Nacional Autonoma de México, between May 2013 and January 2014. Methodology: The natural products had their effect on the light reaction of photosynthesis studied by pollarography and Chlorophyll a (Chl a) fluorescence transients. Results: The compounds inhibited ATP synthesis and electron transport rate (basal, phosphorylating and uncoupled). Therefore, they act as Hill reactions inhibitors. Their inhibition site were located in the range of electron flow from OEC complex and between P680 to QA of PS II, and inhibited the photosystem II (PS II) by inducing the appearance of a K-band which is an indicative that the photochemical apparatus is failing at the donor side of PS II interacting at the OEC complex and by transforming active reaction centers to “heat sinks” or the formation of silent reaction centers unable to reduce QA. Conclusion: Furthermore, these triterpenes inhibit PS II and induce the appearance of small G band which is related with the decreased plastoquinone (PQ) pool reduction.展开更多
In this work we consider the following class of elliptic problems{−Δ_(A)u+u=a(x)|u|^(q−2)u+b(x)|u|^(p−2)u in R^(N),u∈H_(A)^(1)(R^(N)),(P)with 2<q<p<2^(∗)=2N/N−2,a(x)and b(x)are functions that can change sig...In this work we consider the following class of elliptic problems{−Δ_(A)u+u=a(x)|u|^(q−2)u+b(x)|u|^(p−2)u in R^(N),u∈H_(A)^(1)(R^(N)),(P)with 2<q<p<2^(∗)=2N/N−2,a(x)and b(x)are functions that can change sign and satisfy some additional conditions;u∈H_(A)^(1)(R^(N))and A:R^(N)→R^(N) is a magnetic potential.Also using the Nehari method in combination with other complementary arguments,we discuss the existence of infinitely many solutions to the problem in question,varying the assumptions about the weight functions.展开更多
基金the Conselho Nacional de Desenvolvimento Científico e Tecnológico—National Council for Scientific and Technological Development—CNPq for the financial support and the fellowships granted
文摘The two-spotted spider mite, Tetranychus urticae Koch (Tetranychidae), is considered one of the most important species of pest-mites because it is cosmopolite and polyphagous. This species has been described as attacking over 1,100 plant species in 140 families of economic importance. On the other hand, Phytoseiulus macropilis (Banks) (Phytoseiidae) is a predatory mite of group I, specialist as predatory mite from the Tetranychus genus. Thus, the objective of this work was to evaluate predatory potential of P. macropilis in its different stages—nymphs, female and male adults—preying on T. urticae also in different stages—eggs, larvae, nymphs, and adults—and to know the functional and numerical responses in lab studies. Both the experiments were carried out on arenas made of Jack-bean leaflets’ discs [Canavalia ensiformis (L.)—Fabaceae] with 3 cm in diameter over agar-water at 3% inside 5 cm in diameter uncapped Petri dishes. To know the predatory activity, forty T. urticae and one predatory mite were placed in each arena with the respective phases of the developmental life cycle to be evaluated. To know the potential of predation, the no killed mites were counted after 24 hours. To know the functional and numerical responses, immature T. urticae in densities of 1 to 300/arena were offered for P. macropilis. The results for the predatory potential showed that larvae and male adult of T. urticae were the most killed stages, and the female predatory mites were the one that consumed most prey. The functional response showed a positive and significant correlation, suggesting a type II functional response (convex), a cyrtoid curve rising at a decreasing rate to a plateau, where the consumption remains constant regardless of prey density.
基金Project supported by the State of Sao Paulo Research Foundation-FAPESP, Brazil (No. 98/01502-8).
文摘The remaining phosphorus (Prem), P concentration that remains in solution after shaking soil with 0.01 mol L-1 CaCl2 containing 60μg mL-1 P, is a very useful index for studies related to the chemistry of variable charge soils. Although the Prem determination is a simple procedure, the possibility of estimating accurate values of this index from easily and/or routinely determined soil properties can be very useful for practical purposes. The present research evaluated the Prem estimation through multiple regression analysis in which routinely determined soil chemical data, soil clay content and soil pH measured in 1 mol L-1 NaF (pHNaF) figured as Prem predictor variables. The Prem can be estimated with acceptable accuracy using the above-mentioned approach, and pHNaF not only substitutes for clay content as a predictor variable but also confers more accuracy to the Prem estimates.
基金the Brazilian Agricultural Research Corporation(EMBRAPA)for providing the data used in this studythe Sao Paulo Research Foundation(FAPESP)(grant 2013/09050-0,2014/02253-6,2015/08939-0,and 2013/19335-2,respectively)supported by a fellowship from the National Council of Technological and Scientific Development(CNPq)
文摘Background： Recent technological advances in genomics have allowed the genotyping of cattle through single nucleotide polymorphism（SNP） panels. High-density SNP panels possess greater genome coverage and are useful for the identification of conserved regions of the genome due to selection, known as selection signatures（SS）. The SS are detectable by different methods, such as the extended haplotype homozygosity（EHH）; and the integrated haplotype score（i HS）, which is derived from the EHH. The aim of this study was to identify SS regions in Canchim cattle（composite breed）, genotyped with high-density SNP panel.Results： A total of 687,655 SNP markers and 396 samples remained for SS analysis after the genotype quality control. The i HS statistic for each marker was transformed into pi HS for better interpretation of the results.Chromosomes BTA5 and BTA14 showed pi HS 〉 5, with 39 and nine statistically significant SNPs（P 〈 0.00001）,respectively. For the candidate selection regions, i HS values were computed across the genome and averaged within non-overlapping windows of 500 Kb. We have identified genes that play an important role in metabolism,melanin biosynthesis（pigmentation）, and embryonic and bone development.Conclusions： The observation of SS indicates that the selection processes performed in Canchim, as well as in the founder breeds（i.e. Charolais）, are maintaining specific genomic regions, particularly on BTA5 and BTA14. These selection signatures regions could be associated with Canchim characterization.
基金Fundacao Coordenacao de Aperfeicoamento de Pessoal de Nível Superior (CAPES), Fundacao de Amparo a Pesquisa do Estado de Minas Gerais (FAPEMIG [grant number APQ-02349-21])Universidade do Estado de Minas Gerais (UEMG [Productivity Researcher of the UEMG – PQ/UEMG]) for their financial support and fellowships
文摘The use of biochar can have several effects on plant germination,depending on raw material,preparation method and application dose.However,the molecular mechanisms that lead to those results have yet to be elucidated.The aim of this research was to improve the understanding of these mechanisms by characterizing the metabolic effects of sugarcane bagasse biochar on soybean germination.Three types of biochars were prepared by pyrolysis at 300℃(SCB300),400℃(SCB400)and 600℃(SCB600).Then,each one was mixed into sand at 1%,3%,5%(w/w)dose,respectively.The experiment was performed in 8 days of incubation,when the number of germinated seeds and the average radicle length were determined.To evaluate the metabolome,the dry biomass(DB)was subjected to extraction with a mixture of methanol-d4 and D2O(1:1 v/v).The extracts were submitted to metabolomics analysis by Proton Nuclear Magnetic Resonance.The Relative Germination,Relative Average Radicle Growth and Germination Index increased in all treatments compared to control.On the other hand,the DB increased in all treatments,except for SCB300,at doses of 1%and 3%w/w.Seven metabolites(alanine,asparagine,acetic acid,citric acid,glycerol,fatty acids and sucrose)were identified and quantified in DB extracts as the most influential finding for the separation of treatments.Taken together,these results strongly suggested that biochars accelerated the catabolism of triacylglycerols to sucrose and induced a slight osmotic stress.
基金supported by the “Conselho Nacional de Desenvolvimento Científico e Tecnológico”(CNPq)-449,564/2014–2supported by a fellowship from CNPq.NBS received a Post-Doctoral fellowship from CAPES/PNPDsupported by the Sao Paulo Research Foundation(Fapesp)fellowship(2015/08939-0 and 2013/13972-0)
文摘Background： Beef cattle breeding programs in Brazil have placed greater emphasis on the genomic study of reproductive traits of males and females due to their economic importance. In this study, genome-wide associations were assessed for scrotal circumference at 210 d of age, scrotal circumference at 420 d of age, age at first calving, and age at second calving, in Canchim beef cattle. Data quality control was conducted resulting in 672,778 SNPs and 392 animals.Results： Associated SNPs were observed for scrotal circumference at 420 d of age（435 SNPs）, followed by scrotal circumference at 210 d of age（12 SNPs）, age at first calving（six SNPs）, and age at second calving（four SNPs）. We investigated whether significant SNPs were within genic or surrounding regions. Biological processes of genes were associated with immune system, multicellular organismal process, response to stimulus, apoptotic process, cellular component organization or biogenesis, biological adhesion, and reproduction.Conclusions： Few associations were observed for scrotal circumference at 210 d of age, age at first calving, and age at second calving, reinforcing their polygenic inheritance and the complexity of understanding the genetic architecture of reproductive traits. Finding many associations for scrotal circumference at 420 d of age in various regions of the Canchim genome also reveals the difficulty of targeting specific candidate genes that could act on fertility; nonetheless,the high linkage disequilibrium between loci herein estimated could aid to overcome this issue. Therefore, al relevant information about genomic regions influencing reproductive traits may contribute to target candidate genes for further investigation of causal mutations and aid in future genomic studies in Canchim cattle to improve the breeding program.
基金the Conselho Nacional de Desenvolvimento Cientifico e Tecnologico—National Council for Scientific and Technological Development—CNPq,and Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior—Coordination for the Improvement of Higher Education Personnel—CAPES,for financial support and fellowships granted.
文摘The species of mite Oligonychus ilicis (McGregor) (Tetranychidae) is an important pest of dicotyledonous plants, cosmopolitan and polyphagous, reported in seven countries from four continents, feeding on 34 plant species of 15 families. The spider mite O. ilicis is known in Brazil as coffee red spider mite, and as southern red mite most in other countries. In Brazil O. ilicis has been reported as the second most important pest of “Conillon” coffee, Coffea canephora Pierre & Froehner, in the state of Espírito Santo. Depending on the number of mites per leaf of arabica coffee, Coffea arabica L., the rate of potential photosynthesis can be reduced by 37% to 50%. In the present study, it was investigated the potential of the two predatory mites which, among others, naturally occurs in coffee plantations, Euseius alatus DeLeon and Amblyseius herbicolus (Chant) (Phytoseiidae), in the control of O. ilicis in coffee plants. It was used potted coffee plants in this research, with approximately 100 cm high, growing in a greenhouse covered with transparent plastic and shading material of 50% sun protection factor, and with fine mesh on all the sides. Results showed that both species of predatory mites, A. herbicolus and E. alatus, are efficient in reducing the mobile phases—larvae, protonymphs, deutonymphs and adults—of the southern red mite O. ilicis. So, the importance of conservation and increase number of these predatory mites in the field coffee growing is essential for implementing the southern red mite integrated management tactic, since these species are of natural occurrence in coffee plants.
基金CNPq of Brazil for partial financial support of this work.
文摘A spectral method based on Hermite cubic splines expansions combined with a collocation scheme is used to develop a solution for the vector form integral S-model kinetic equation describing rarefied gas flows in cylindrical geometry. Some manipulations are made to facilitate the computational treatment of the singularities inherent to the kernel. Numerical results for the simulation of flows generated by pressure and thermal gradients, Poiseuille and thermal-creep problems, are presented.
基金financial support of the DGAPA-UNAM IT102012-3#FAPESP(Fundacao de Amparo a Pesquisa do Estado de Sao Paulo)+1 种基金#CNPq(Conselho Nacional de Pesquisa e Desenvolvimento)CAPES(Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior).
文摘Aims: Cabraleadiol (1), Ocotilone (2) and Odoratone (3) are three triterpenes isolated from Cabralea canjerana (Vell.) Mart. (Meliaceae). They were chemically characterized, and their effect was tested on the light reaction of photosynthesis. Study Design: Natural products were used as models to find new models for inhibitors of photosynthesis. Place and Duration of Study: Departmento de Química, Universidade Federal de São Carlos and Departmento de Bioquímica, Facultad de Química, Universidad Nacional Autonoma de México, between May 2013 and January 2014. Methodology: The natural products had their effect on the light reaction of photosynthesis studied by pollarography and Chlorophyll a (Chl a) fluorescence transients. Results: The compounds inhibited ATP synthesis and electron transport rate (basal, phosphorylating and uncoupled). Therefore, they act as Hill reactions inhibitors. Their inhibition site were located in the range of electron flow from OEC complex and between P680 to QA of PS II, and inhibited the photosystem II (PS II) by inducing the appearance of a K-band which is an indicative that the photochemical apparatus is failing at the donor side of PS II interacting at the OEC complex and by transforming active reaction centers to “heat sinks” or the formation of silent reaction centers unable to reduce QA. Conclusion: Furthermore, these triterpenes inhibit PS II and induce the appearance of small G band which is related with the decreased plastoquinone (PQ) pool reduction.
基金grants from FAPESP 2017/16108-6grants from FAPESP 2019/24901-3 and CNPq 307061/2018-3supported by CAPES/Brazil and the paper was completed while the second author was visiting the Departament of Mathematics of UFJF whose hospitality she gratefully acknowledges.
文摘In this work we consider the following class of elliptic problems{−Δ_(A)u+u=a(x)|u|^(q−2)u+b(x)|u|^(p−2)u in R^(N),u∈H_(A)^(1)(R^(N)),(P)with 2<q<p<2^(∗)=2N/N−2,a(x)and b(x)are functions that can change sign and satisfy some additional conditions;u∈H_(A)^(1)(R^(N))and A:R^(N)→R^(N) is a magnetic potential.Also using the Nehari method in combination with other complementary arguments,we discuss the existence of infinitely many solutions to the problem in question,varying the assumptions about the weight functions.
