Collective and fractal properties of pion jets in the four-velocity space at intermediate energies

Experimental results are presented for study of collective and fractal properties of soft pion jets in the space of relative four-dimensional velocities. Significant decreasing is obtained for mean square of second particle distances from jet axis for pion-proton interactions at initial energies $\sim 3$ GeV in comparison with hadron-nuclear collisions at close energies. The decreasing results in power dependence of distance variable on collision energy for range $\sim 2 - 4$ GeV. The observation allows us to estimate the low boundary of manifestation of color degree of freedom in pion jet production. Cluster dimension values were deduced for pion jets in various reactions. Fractional values of this dimension indicate on the manifestation of fractal-like properties by pion jets. Changing of mean kinetic energy of jet particles and fractal dimension with initial energy increasing is consistent with suggestion for presence of color degrees of freedom in pion jet production at intermediate energies.Comment: The conference "Physics of fundamental interactions". ITEP, Moscow, Russia. November 23 - 27, 200

STUDY OF BIOCHEMICAL AND MOLECULAR MECHANISMS INVOLVED IN THE REGULATION OF RIPENING IN THE CLIMACTERIC PEACH (PRUNUS PERSICA L. BATSCH) FRUIT

Abstract Peach (Prunus persica[L.] Batsch) is temperate fruit species of economic importance, it ranks second in fruit production in Europe after apple. Peach fruit are classified by different flesh firmness, which strongly influences fruit shelf-life and storage, and ethylene evolution, which determinates the organoleptic quality of the ripening fruit. Concerning flesh texture, three main distinct peach fruit phenotypes are known, even if not all is understood in terms of their genetic determination and differences in biochemical pathways activated during the final stages of ripening which lead to the definition of phenotypic-specific characteristics. The first two phenotypes, described by Bailey and French, 1932, are the melting (M) and non-melting (NM) flesh. The M texture shows a prominent softening in the final stage of ripening. Variability of firmness is found within this phenotype and Yoshida (1976) distinguished between soft, medium and firm. The NM phenotype (the so called \u2018canning peach\u2019) shows a firm texture when fully ripe that never becomes soft. Rather, it becomes rubbery (for the loss of water from the tissues) during the senescence stage, when most cultivars could also display the development of peculiar off-flavours (Sherman et al., 1990). The third flesh texture phenotype was described by Yoshida (1976). He firstly classified a very firm and crispy, \u2018stony hard\u2019 (SH) flesh phenotype as belonging to the M family. However, these fruit never soften and resemble a NM phenotype, becoming rubbery when senescent. A possible fourth flesh texture trait resembles very much the SH flesh in firmness and crispiness, but when fully ripe becomes melting. This flesh texture is found in many recently developed new cultivars (nectarines, as \u2018Big Top\u2019, and standard peaches, e.g. \u2018Rich Lady\u2019 and \u2018Diamond Princess\u2019; Monet and Bassi, 2008). Availability of newly established peach cultivars with optimal organoleptic (as for M phenotypes) and durability [as for NM, SH and Slow Melting (\u2018Big Top\u2019) phenotypes] characteristics would represent an economic advantage improving shelf-life and economic value of the produce. To do this, and in order to plan proper breeding programmes, a possible strategy may consist in the identification of molecular markers linked to the \u201cflesh texture\u201d phenotype. In this work, particular attention has been devoted to the development of different characteristics of flesh texture as a function of the structure of the endo-PG gene and of fruit ethylene evolution and response. The research work was articulated in four main topics: 1. Chapter I reports the results of some physiological, biochemical and molecular aspects of the Melting of the \u2018Big Top\u2019 Nectarine Fruit. We have characterized the postharvest behavior of \u2018Big Top\u2019 fruit, treated or not with ethylene for five days after harvest (DAH), and compared it with that of \u2018193 Q XXVII 111\u2019, a SH peach selection (\u2018Ghiaccio\u2019), and with that of an accession with very firm flesh, \u2018D41-62\u2019. Pp-ACS1 expression, ethylene evolution, endo-PG production and softening characteristics have been evaluated in fruit of the three genotypes and referred to those of ripe melting flesh (M) \u2018Bolero\u2019 at harvest. Like \u2018Bolero\u2019, \u2018Big Top\u2019 fruit did express Pp-ACS1 and evolve ethylene, but with a 5-d delay during postharvest. Pp-endo-PG expression, production of an active endo-PG isoform typical of ripe peach fruits and fruit melting showed a parallel behavior; ethylene treatment further enhanced all the above features. In SH \u2018Ghiaccio\u2019 Pp-ACS1 expression, ethylene evolution, endo-PG production and softening were virtually absent during the first five DAH in air. \u2018Ghiaccio\u2019 neither expressed Pp-ACS1 nor evolved ethylene even after ethylene treatment, but responded by accumulating Pp-endo-PG transcripts and an active endo-PG protein, thus with consequent flesh melting. A similar behavior was observed in \u2018D41-62\u2019. Overall, the data confirm the pivotal role of ethylene in the regulation of endo-PG expression and activity, and thus in the determination of peach fruit flesh texture characteristics, and support the evidence that \u2018Big Top\u2019 could be classified as belonging to the \u2018melting\u2019 (\u2018slow melting\u2019) phenotype and \u2018D41-62\u2019 to the SH one. 2. Chapter II describes the EndoPG locus configuration in different peach genotypes. The work has been undertaken with the aim of ascertaining whether specific mutations (SNPs or InDel polymorphisms, assessed by CAPS or InDel analysis) at the level of the Pp-endoPG gene could be used as molecular markers for prediction of fruit phenotype. To do so, a preliminary screening has been conducted on a few established cultivars on the progenies of a few selected crosses identifying, at the level of the endoPG gene, the patterns of InDel amplification and CAPS restriction patterns and comparing them with fruit texture (M, NM, SH, Slow Melting) phenotype. The results, albeit preliminary and to be confirmed on a larger number of selection from controlled crosses, seemed to provide satisfactory matching between the molecular results and fruit phenotype. 3. Chapter III reports the isolation and preliminary analysis of Pp-endoPG promoter region in Melting, Non Melting amd Slow Melting flesh genotypes. The sequences of the 5\u2019 upstream region of the m Pp-endoPG clone of both NM \u2018Oro A\u2019 and M \u2018Bolero\u2019, of the M clone of M \u2018Bolero and of the BT clone of Slow Melting \u2018Big Top\u2019 were obtained. PLACE analysis showed the presence in different positions of the isolated promoter sequences of a few interesting cis-acting elements, differently involved in the plant responses to endogenous (phytohormones) and exogenous (light, water stress, etc.) factors suggesting a possible fine regulation of Pp-endoPG expression by several factors. Particularly interesting was retrieval of microsatellites, possibly exploitable as molecular markers for the identification of the fruit phenotype, and of an Ethylene Responsive Element (ERE). The latter one was present in the 5\u2019 upstream region of clones m-B and BT and in M clone, while in the 5\u2019 upstream region of clone m-O a SNP was identified an altered ERE motif. This result may possibly explain the lower expression of Pp-endoPG observed in the high ethylene-producing NM cultivar \u2018Oro A\u2019. Preliminary gel Electrophoresis Mobility Shift Assay (EMSA) gave the indication of a stronger interaction with nuclear protein of the promoter region of clone m-B (containing ERE motif) with respect to clone m-O. This result, though needing to be confirmed by further experiments, appears consistent with the different expression profiles of the Pp-endoPG gene as related to softening behaviour 4. Chapter IV describes the preliminary characterization of some physiological and biochemical traits of fruit of one (BO 95021043) of the selections available at the Di.Pro.Ve., and of their response to treatment, in the postharvest period, with ethylene and/or with its antagonist, 1-methyl-1-cyclo-propene (1-MCP). The results obtained confirmed that these fruit were blocked in the evolution of all the ripening-related parameters. This physiological blockade was accompanied by an overall extremely low and constant degree of expression of a few genes playing a key role in ripening-related process. Lack of endogenous ethylene evolution in SR mutants seemed related to block of the expression of the Pp-ACO1 gene. SR fruit, though, were able to respond to ethylene treatment as demonstrated by the ethylene-induced slight enhancement of ripening-related parameters. Cleaved Amplified Polymorphis Sequence (CAPS) investigation on the structure of the Pp-endoPG gene in the SR BO 92051043 selection indicated the presence of two SNPs (SNP390 and SNP1310) common also to \u2018Big Top\u2019, \u2018Ghiaccio\u2019 and \u2018Yumyeong\u2019, possibly indicative of a parentage between these lines

Battle in the New World: \u3ci\u3eHelicoverpa armigera\u3c/i\u3e versus \u3ci\u3eHelicoverpa zea\u3c/i\u3e (Lepidoptera: Noctuidae)

The corn earworm Helicoverpa zea (Boddie) and the old world bollworm Helicoverpa armigera (HuÈbner) (Lepidoptera: Noctuidae) are allopatric species and occur in important agricultural crops. In maize, both species tend to infest the ear. The introduction of H. armigera in Brazil has created a new scenario, where these Helicoverpa species might cohabit and interact with one another, affecting the prevalence of each species in the agroecosystem, integrated pest management, and insect resistance management. In this study, larval occurrence and proportion of these species in maize was assessed in three regions of Brazil during three crop seasons. Interaction between the species was evaluated in interspecific and intraspecific scenarios under laboratory and field conditions. Helicoverpa zea was predominant in Rio Grande do Sul and the Planaltina, DF (central Brazil). In western Bahia, H. zea was predominant in the first collection, but approximately equal in number to H armigera in the second crop season. Both species exhibit high cannibalism/predation rates, and larval size was the primary factor for larval survival in the interaction studies. Larva of H. zea had higher survival when interacting with H. armigera, indicating that H. zea has an advantage in intraguild interactions with H. armigera in maize. Overall, the results from this study indicate that maize might play a role as a source of infestation or a sink of insecticide or Bt protein unselected H. armigera populations, depending on the H. zea:H. armigera intraguild competition and adult movement in the landscape

Adaptações de metodologia para criação de Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae).

Helicoverpa armigera (Hübner) destaca-se entre os principais lepidópteros desfolhadores de culturas brasileiras nas duas últimas safras. Visando aprimorar as técnicas de criação de H. armigera em laboratório, foi avaliada uma metodologia de criação no Laboratório de Resistência de Plantas a Insetos e Plantas Inseticidas (LARESPI) da FCA/UNESP, Botucatu. Para criação, os adultos identificados quanto ao sexo e separados em casais são mantidos em gaiolas (tubos de PVC, 20 cm de diâmetro e 30 cm de altura). A face superior das gaiolas são vedadas com tecido voil, permitindo aeração e alimentação dos adultos. A face inferior é apoiada em prato de plástico (28 cm de diâmetro) recoberto com papel filtro. Internamente as gaiolas são forradas com papel kraft natural servindo de substrato para oviposição. Sobre o voil é acondicionada uma porção de algodão umedecido em solução de mel a 10%, e outra contendo apenas água. As lagartas são obtidas a partir das posturas colhidas diariamente no papel kraft e no tecido voil. As posturas são transferidas inicialmente para um recipiente plástico transparente de 500 mL, contendo aproximadamente 50g de dieta artificial. A partir do terceiro instar, é feita a transferência individual das lagartas para recipientes de 50 mL, contendo aproximadamente 5g de dieta artificial. Estes recipientes são vedados com tampas, e as lagartas são mantidas em seu interior até formação das pupas. As pupas são coletadas e acondicionadas em recipientes de acrílico transparente (11,5 x 11,5 x 3,5 cm) contendo vermiculita umedecida, permanecendo nesse ambiente até a emergência dos adultos. A criação é mantida sob temperatura de 25ºC, umidade relativa de 70±10% e fotofase de 12h. A iluminação natural é mantida por lâmpadas dos tipos fluorescente ?super luz do dia? (20W) e fluorescente ?plant light? (grolux F 20 W T12), nas prateleiras de criação. Para averiguação de temperatura e umidade relativa do ar utiliza-se o termohigrômetro digital. Para validação da criação descrita realizaram-se diversos experimentos preliminares. A metodologia apresentada possibilita a criação de H. armigera em diferentes escalas, permitindo a realização de ensaios diversos

External marking and behavior of early instar \u3ci\u3eHelicoverpa armigera\u3c/i\u3e (Lepidoptera: Noctuidae) on soybean

Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) is a pest of major agricultural crops, such as soybean and cotton. A better understanding of larval movement is important for its integrated management and resistance management. Studies with neonates through second instar larvae are still limited by the difficulties involving the handling and observation of these instars. Many studies require marking larvae, and most research involving marking is focused on moths. However, our study investigated aspects of larval behavior of the second instar of H. armigera on soybean plants. The dyes luminous powder red and Sudan Red 7B were tested as external larval markers. Both dyes successfully marked the larvae for most of 1 stadium (48 h) without deleterious effects, and are useful for short-period behavioral studies. Luminous powder red was selected for the H. armigera larval behavior study on soybean because of ease of detection during both day and night. Second instar on-plant movement was consistent, independent of the d period (morning, afternoon, evening). In general, larvae established their feeding site within a few hours of release, and remained feeding on soybean leaves. Second instar behavior suggests that management by nocturnal insecticide application, based on H. armigera larval movement, would not have an advantage over daytime application. Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) está entre as principais pragas de importancia para culturas agrícolas, como soja e algodão. Compreender o comportamento larval desta espécie, principalmente durante os estádios iniciais é de suma importância para seu manejo integrado e para o manejo de populações resistentes. No entanto, pesquisas com neonatas ou lagartas de segundo ínstar são limitadas devido às dificuldades envolvendo o manuseio e observação de insetos tão diminutos. Muitos desses estudos requerem a marcação de indivíduos, e até o momento, a maioria das pesquisas com marcação de insetos é focada em adultos. Assim, nosso estudo investigou aspectos do comportamento de lagartas de segundo instar de H. armigera em plantas de soja. Estudos prévios também foram realizados com o intuito de se avaliar métodos alternativos e eficazes para marcação de estádios iniciais das larvas desse noctuídeo e suas aplicações em estudos de comportamento. Para tanto, os corantes luminous powder (azul e vermelho) e Sudan (azul e vermelho 7B) foram testados por meio da incorporação em dieta artifical e polvilhamento sobre as lagartas. Baseado em nossos ensaios prévios de laboratório, os corantes incorporados na dieta artifical apresentaram efeitos variáveis sobre os parâmetros biológicos de H. armigera e baixa persistência após o segundo ínstar. Os corantes aplicados por polvilhamento marcaram com sucesso as lagartas e luminous powder vermelho foi selecionado para o estudo de comportamento de lagartas de segundo ínstar em plantas de soja. Lagartas de segundo ínstar apresentaram comportamento de movimento nas plantas semelhantes, independentemente do período de avaliação (manhã, tarde e noite). Em geral, a maioria das lagartas estabeleceram seu sítio de alimentação após algumas horas e permaneceram se alimentando sobre as folhas de soja. Os resultados de comportamento de larvas de H. armigera em segundo instar, documentado no presente trabalho, indicam que aplicacões noturnas de insecticidas não representa vantagem para aumento da eficiência de controle, quando comparado com aplicacões de inseticidas durante o dia

Jet Energy Density in Hadron-Hadron Collisions at High Energies

The average particle multiplicity density dN/deta is the dynamical quantity which reflects some regularities of particle production in low-pT range. The quantity is an important ingredient of z-scaling. Experimental results on charged particle density are available for pp, pA and AA collisions while experimental properties of the jet density are still an open question. The goal of this work is to find the variable which will reflect the main features of the jet production in low transverse energy range and play the role of the scale factor for the scaling function psi(z) and variable z in data z-presentation. The appropriate candidate is the variable we called "scaled jet energy density". Scaled jet energy density is the probability to have a jet with defined ET in defined xT and pseudorapidity regions. The PYTHIA6.2 Monte Carlo generator is used for calculation of scaled jet energy density in proton-proton collisions over a high energy range (sqrt s = 200-14000 GeV) and at eta = 0. The properties of the new variable are discussed and sensitivity to "physical scenarios" applied in the standard Monte Carlo generator is noted. The results of scaled jet energy density at LHC energies are presented and compared with predictions based on z-scaling.Comment: 11 pages, LaTeX, 8 figures, Presented at the XVII International Baldin Seminar on High Energy Physics Problems "Relativistic Nuclear Physics & Quantum Chromodynamics", Dubna, Russia, September 27 - October 2, 200

Feeding behavior of \u3ci\u3eAphis glycines\u3c/i\u3e (Hemiptera: Aphididae) on soybeans exhibiting antibiosis, antixenosis, and tolerance resistance

Aphis glycines Matsumura (Hemiptera: Aphididae) is a serious pest of soybean in North America. Plant resistance is a valuable tool for the management of this pest, and a better understanding of the interactions between aphid and soybeans expressing varying levels and different categories of resistance can assist in the development of aphid resistant or tolerant genotypes. The electrical penetration graph (EPG) technique was used to evaluate the feeding behavior of A. glycines (biotype 1) on 4 soybean genotypes: (1) ‘Dowling’ (contains Rag1 gene and exhibits antibiosis); (2) PI 200538 (contains Rag2 gene and exhibits antixenosis); (3) KS4202 (exhibits tolerance); and (4) ‘SD76RR’ (susceptible to aphid). Aphids spent shorter periods in the sieve element phase on ‘Dowling’ and exhibited a greater number of pathway phases, non-probing events, and a longer time in nonprobing events in PI 200538 and ‘Dowling.’ For ‘SD76RR’ and KS4202, aphids demonstrated more sustained phloem ingestion, spent shorter time in non-probing events, and exhibited fewer pathway phases and potential drops. These results indicate that resistance factors are present in the phloem of ‘Dowling.’ For PI 200538, it is suggested that antixenotic factors are involved in resistance to A. glycines. Because KS4202 is tolerant to biotype 1 of A. glycines, the suitability of this genotype was expected already. This study provides important data that contribute to the understanding of how soybean aphids (biotype 1) feed on soybean genotypes with various aphid resistant genes and categories. In addition to assisting in the distinction between resistance categories, these results are useful in soybean breeding programs focusing on developing genotypes with greater resistance to insects. Aphis glycines Matsumura (Hemiptera: Aphididae) é uma das principais pragas da cultura da soja na América do Norte. Dentre as técnicas de manejo da praga, a resistência de plantas a insetos se destaca como uma ferramenta valiosa. Assim, uma melhor compreensão sobre as interações entre o afídeo e plantas de soja que expressam variáveis níveis e diferentes categorias de resistência, pode auxiliar no desenvolvimento de genótipos resistentes ao inseto. A técnica de EPG foi utilizada para avaliar o comportamento alimentar de A. glycines (biótipo 1) em 4 genótipos de soja: (1) ‘Dowling’ (contém gene Rag1 e expressa antibiose); (2) PI 200538 (contém gene Rag2 e expressa antixenose); (3) KS4202 (expressa tolerância); e (4) ‘SD76RR’ (suscetível ao afídeo). Os afídeos demonstraram curtos períodos de alimentação na fase de seiva em ‘Dowling’ e exibiram uma grande quantidade de fases de caminhamento estiletar, número de períodos de não-prova e longos período de não-prova em PI 200538 e ‘Dowling.’ Para ‘SD76RR’ e KS4202, os afídeos mostraram um maior período de alimentação em vasos do floema, apresentaram curtos períodos de não-prova e exibiram poucas fases de caminhamento estiletar, além de menor número de quedas de potencial. Os resultados indicam que fatores de resistência estão presentes nos vasos floemáticos de ‘Dowling.’ Para PI200538, sugere-se que fatores antixenóticos estão envolvidos na resistência a A. glycines. Uma vez que KS4202 expressa tolerância ao biótipo 1 de A. glycines, a adequabilidade deste genótipo como fonte de alimento para o inseto já era esperada. Este estudo fornece importantes dados que contribuem para um melhor entendimento de como o pulgão-da-soja (biótipo 1) se alimentam de plantas de soja portadoras de diferentes genes e categorias de resistência. Além de auxiliar na distinção entre as categorias de resistência, esses resultados podem ser úteis em programas de melhoramento de soja, com intuito de selecionar genótipos mais resistentes a insetos

Feeding behavior of \u3ci\u3eAphis glycines\u3c/i\u3e (Hemiptera: Aphididae) on soybeans exhibiting antibiosis, antixenosis, and tolerance resistance

Aphis glycines Matsumura (Hemiptera: Aphididae) is a serious pest of soybean in North America. Plant resistance is a valuable tool for the management of this pest, and a better understanding of the interactions between aphid and soybeans expressing varying levels and different categories of resistance can assist in the development of aphid resistant or tolerant genotypes. The electrical penetration graph (EPG) technique was used to evaluate the feeding behavior of A. glycines (biotype 1) on 4 soybean genotypes: (1) ‘Dowling’ (contains Rag1 gene and exhibits antibiosis); (2) PI 200538 (contains Rag2 gene and exhibits antixenosis); (3) KS4202 (exhibits tolerance); and (4) ‘SD76RR’ (susceptible to aphid). Aphids spent shorter periods in the sieve element phase on ‘Dowling’ and exhibited a greater number of pathway phases, non-probing events, and a longer time in nonprobing events in PI 200538 and ‘Dowling.’ For ‘SD76RR’ and KS4202, aphids demonstrated more sustained phloem ingestion, spent shorter time in non-probing events, and exhibited fewer pathway phases and potential drops. These results indicate that resistance factors are present in the phloem of ‘Dowling.’ For PI 200538, it is suggested that antixenotic factors are involved in resistance to A. glycines. Because KS4202 is tolerant to biotype 1 of A. glycines, the suitability of this genotype was expected already. This study provides important data that contribute to the understanding of how soybean aphids (biotype 1) feed on soybean genotypes with various aphid resistant genes and categories. In addition to assisting in the distinction between resistance categories, these results are useful in soybean breeding programs focusing on developing genotypes with greater resistance to insects. Aphis glycines Matsumura (Hemiptera: Aphididae) é uma das principais pragas da cultura da soja na América do Norte. Dentre as técnicas de manejo da praga, a resistência de plantas a insetos se destaca como uma ferramenta valiosa. Assim, uma melhor compreensão sobre as interações entre o afídeo e plantas de soja que expressam variáveis níveis e diferentes categorias de resistência, pode auxiliar no desenvolvimento de genótipos resistentes ao inseto. A técnica de EPG foi utilizada para avaliar o comportamento alimentar de A. glycines (biótipo 1) em 4 genótipos de soja: (1) ‘Dowling’ (contém gene Rag1 e expressa antibiose); (2) PI 200538 (contém gene Rag2 e expressa antixenose); (3) KS4202 (expressa tolerância); e (4) ‘SD76RR’ (suscetível ao afídeo). Os afídeos demonstraram curtos períodos de alimentação na fase de seiva em ‘Dowling’ e exibiram uma grande quantidade de fases de caminhamento estiletar, número de períodos de não-prova e longos período de não-prova em PI 200538 e ‘Dowling.’ Para ‘SD76RR’ e KS4202, os afídeos mostraram um maior período de alimentação em vasos do floema, apresentaram curtos períodos de não-prova e exibiram poucas fases de caminhamento estiletar, além de menor número de quedas de potencial. Os resultados indicam que fatores de resistência estão presentes nos vasos floemáticos de ‘Dowling.’ Para PI200538, sugere-se que fatores antixenóticos estão envolvidos na resistência a A. glycines. Uma vez que KS4202 expressa tolerância ao biótipo 1 de A. glycines, a adequabilidade deste genótipo como fonte de alimento para o inseto já era esperada. Este estudo fornece importantes dados que contribuem para um melhor entendimento de como o pulgão-da-soja (biótipo 1) se alimentam de plantas de soja portadoras de diferentes genes e categorias de resistência. Além de auxiliar na distinção entre as categorias de resistência, esses resultados podem ser úteis em programas de melhoramento de soja, com intuito de selecionar genótipos mais resistentes a insetos