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Salmonella is one of the leading causes of foodborne disease worldwide, usually related to contaminated poultry or poultry products, such as eggs. Since egg contamination with Salmonella depends on multiple factors that make it challenging to control, consumers' knowledge about food safety and the proper handling of eggs is crucial. The aims of the study were (1) to determine the prevalence of Salmonella in eggs from conventional and alternative production systems, (2) to characterize the Salmonella isolates according to phenotypic-genotypic and antimicrobial-resistant traits, and (3) to understand how consumers manage the hazards related to egg contamination in the household. A total of 426 egg samples were analyzed (conventional systems = 240; alternative systems = 186). Culture-based and molecular microbiological methods were used to identify Salmonella and bioinformatics analysis of whole genome sequences was used to determine the serotype and antimicrobial-resistant genes. Salmonella enterica serotype Enteritidis was detected only in eggs from alternative systems (1.1%, 2/186). Isolates showed resistance to nalidixic acid (100%, 2/2), and the aac(6′)-Iaa gene and a mutation in the gyrA gene were identified in both isolates. Overall, consumers demonstrated knowledge regarding food safety; however, many still engage in practices that pose a risk of acquiring foodborne illnesses. [ABSTRACT FROM AUTHOR]

Social media has changed the landscape of adolescence, altering how young people communicate and connect with peers. This study explores how young women of color living in marginalized neighborhoods perceive, manage, and make meaning of social media threats and conflict. Previous research shows that social media narratives tend to reify gender differences and devalue the experiences of conflict among girls and young women. Focus group discussions among 41 youth, living in a disinvested neighborhood of Hartford, CT, and participating in a development program for adolescents at risk for violence involvement, suggest that girls use social media platforms to define, negotiate, and meet their developmental needs and enhance their wellbeing. These adolescents are intentional in their choices to enter the social media world; they use social media to cultivate their identity, protect their reputation, manage relationships, or simply be seen and heard. While corroborating previous findings concerning perceptions of social media conflicts, these girls were not passive consumers of social media; they had a nuanced sense of this tool and used it to resist violence and benefit their image. Identifying adolescent insights about how particular social media features influence conflict is critical to creating effective interventions. [ABSTRACT FROM AUTHOR]

Graciela Olivárez became the first Latina law professor in 1972, thirty-two years after the first Latina was admitted to a state bar in the United States. Fifty years after Graciela Olivárez became a law professor, a group of Latina law professors gathered for the 2022 Inaugural Graciela Olivárez Latinas in the Legal Academy ("GO LILA") Workshop. As a result of the workshop, we learned that we have accomplished much despite many obstacles. We also learned that we lag behind, including in our efforts to organize a collective movement to improve our professional opportunities in the legal academy. There is much work left to do. The GO LILA Workshop will hopefully create a space for Latinas in the Legal Academy ("LILA" or "LILAs") to come together una para todas y todas para una. This paper documents what we hope will be the first of many GO LILA Workshops, to memorialize the event for LILAs who come after. [ABSTRACT FROM AUTHOR]

In Mexico, some plants of the Salvia genus are employed against digestive problems, circulatory problems, infections, and some hematological alterations. We evaluated the effect of Salvia purpurea Cav. (Labiateae) on the proliferation of mouse hematopoietic cells. The extracts were prepared by consecutive maceration with hexane, dichloromethane, methanol, and water from three mixtures of the aerial structures of the plant: flower; flower-leaf, and flower-leaf-stem. Their hematopoietic capacity was determined in cultures of mouse bone marrow and spleen utilizing concentrations of 1, 10, and 100 µg/mL of each extract. The 100-µg/mL concentration of the flower extracts obtained with hexane, dichloromethane, and water established the proliferation of bone-marrow cells. The 10-µg/mL concentration of the hexanic and dichloromethanic extracts reduced cellularity by 34 ad 33%, respectively (p <0.005). Likewise, the 10-µg/mL concentration of the hexanic extract reduced the cell count by 30% (p <0.025). The 100-µg/mL concentration of the four flower-leaf extracts increased the concentration from 135-174%. Of the 36 extracts tested in bone marrow, 14 were stimulants, 19 were cytostatic, and three, cytotoxic. The remaining extracts increased the cellular concentration from 127 to 199.6%. In spleen cultures, the 100-µg/mL concentration of the flower-leaf-stem, and the hexanic and methanolic extracts increased the cellular concentration. The 100-µg/mL concentration of the flower-leaf extracts obtained with dichloromethane and water gave rise to 4.0 and 3.4 increments in the cell count, respectively. The phytochemical study revealed the presence of phenolic and saponin compounds. [ABSTRACT FROM AUTHOR]

In addressing the grand challenge to build healthy relationships to end violence, social workers continue to engage in helping individuals affected by intimate partner violence (IPV). IPV often results in negative mental health and physical health outcomes. This qualitative study explored Latina immigrant women's experiences of IPV by using an intersectional Chicana feminist approach. Twenty Latina undocumented immigrants who experienced IPV shared their testimonio interviews to denounce the injustices they experienced when seeking help. A narrative analysis is presented to illustrate some of the ineffective responses the participants experienced when seeking help as well as effective responses that provided them support. The analysis of the survivors' testimonios also offered detailed stories to help us understand the intersectional experiences related to the survivors' gender, ethnicity, social class, and undocumented immigration status when seeking help. Providing support to Latina immigrant survivors requires a better understanding of the unique help-seeking barriers they encounter in the United States. Implications from this study suggest that in order to effectively support the health of undocumented survivors of IPV, social workers need to consider trust building and be prepared to respond to the current political climate and institutional barriers when providing services for undocumented immigrant survivors. [ABSTRACT FROM AUTHOR]

In the article, the author examines the disproportional effects of COVID-19 on African Americans. Also cited are the number of Americans who were infected and died due to the disease as of October 2020, the factors affecting African American communities in the U.S. like poor social policies and programs and unfair economic arrangements, and how social rights can advance people's citizenship and participation in society.

Research demonstrates a growing number of exploited and trafficked children in the United States, but few studies address how practitioners continue to respond to these issues. Multiple efforts identify victims of human trafficking and provide services since the passing of the Trafficking Victims Protection Act (TVPA) in 2000 and its reauthorization. However, the TVPA oftentimes failed to protect the most vulnerable. This qualitative study included four focus group sessions with 28 practitioners from various disciplines (e.g., social work, healthcare, legal) to examine how the state of Connecticut has expanded services and programs for children and youth trafficking victims. The findings describe current statewide partnerships along with challenges and successes when working with child victims of human trafficking, offering practice and policy recommendations. [ABSTRACT FROM AUTHOR]

This paper investigates how high school students in an introductory computer science (CS) course approach computing in the logic programming (LP) paradigm. This qualitative study shows how novice students operate within the LP paradigm while engaging in foundational computing concepts and skills: students are engaged in a cyclical process of abstraction, reasoning, and creating representations of their ideas in code while also being informed by the (procedural) requirements and the revision/debugging process. As these computing concepts and skills are also expected in traditional approaches to introductory K-12 CS courses, this paper asserts that LP is a viable paradigm choice for high school novices. [ABSTRACT FROM AUTHOR]

Increasing inoculation time during Agrobacterium-mediated transformation has been shown to favour transformation efficiency in several plant species. The effect of inoculation time in combination with spermidine (Spd) on efficiency was determined during Agrobaterium-mediated transformation of the Musa cultivar 'Grande naine' (AAA). Banana embryogenic cell suspensions (ECSs) were incubated with the bacterial strain EHA 105 carrying the binary vector pFAJ3000. Six different inoculation conditions (6 h, 6 h+Spd, 12 h, 12 h+Spd, 24 h, 24 h+Spd) were compared based on transient GUS expression and number of embryo colonies formed. Moreover, leaf fragments from 24 randomly chosen regenerated plantlets were assayed presence and expression of the transgenes. Consequently, samples that were inoculated for 24 h in medium supplemented with 1 mM spermidine showed the highest transformation efficiency, expressed as number of blue foci and regenerated colonies after the selection treatment. Here we showed for the first time that longer inoculation times in combination with spermidine enhance the efficiency of Agrobacterium-mediated transformation of the banana cultivar 'Grande naine'. [ABSTRACT FROM AUTHOR]

Insect pollination is of great importance to crop production worldwide and honey bees are amongst its chief facilitators. Because of the decline of managed colonies, the use of sensor technology is growing in popularity and it is of interest to develop new methods which can more accurately and less invasively assess honey bee colony status. Our approach is to use accelerometers to measure vibrations in order to provide information on colony activity and development. The accelerometers provide amplitude and frequency information which is recorded every three minutes and analysed for night time only. Vibrational data were validated by comparison to visual inspection data, particularly the brood development. We show a strong correlation between vibrational amplitude data and the brood cycle in the vicinity of the sensor. We have further explored the minimum data that is required, when frequency information is also included, to accurately predict the current point in the brood cycle. Such a technique should enable beekeepers to reduce the frequency with which visual inspections are required, reducing the stress this places on the colony and saving the beekeeper time. [ABSTRACT FROM AUTHOR]

The codling moth, Cydia pomonella (L.), is the key pest of apple production worldwide. Insecticide resistance has been reported in all producing countries, based on five different mechanisms. Codling moth in Chile has resistance to azinphos-methyl and tebufenozide in post-diapausing larvae. However, there are no studies about the susceptibility of these populations to insecticides from other chemical groups. Therefore, the efficacy of azinphos-methyl, chlorpyrifos-ethyl, esfenvalerate, methoxyfenozide, tebufenozide, and thiacloprid on neonate and post-diapausing larvae from six field populations was investigated, and identified resistance mechanisms in this species were evaluated. Neonate larvae were susceptible to all insecticides studied, but post-diapausing larvae from four populations were resistant to chlorpyrifos, one of them was also resistant to azinphos-methyl, and another one was resistant to tebufenozide. The acetylcholinesterase insensitivity mutation was not detected, and the sodium channel knockdown resistance mutation was present in a low frequency in one population. Detoxifying enzymatic activity of glutathione S-transferases, esterases, and cytochrome P-450 monooxygenases in adults differed among populations, but chlorpyrifos resistance was associated only with a decreased esterase activity as shown by a significant negative correlation between chlorpyrifos mortality and esterase activity. [ABSTRACT FROM PUBLISHER]

The article discusses gender equality in America in relation to the various ways in which man-made professional and workplace norms silence professional women as of 2015. Women’s rights are addressed, along with U.S. federal courts and the author’s personal experiences with adacdemic feminism and the legal academy. Discrimination against women in the workplace is examined, including incidents involving American law professor Anita Hill and Libyan attorney Iman al-Obeidi.

The extraction methods of genomic DNA are usually laborious and hazardous to human health and the environment by the use of organic solvents (chloroform and phenol). In this work a protocol for in situ extraction of genomic DNA by alkaline lysis is validated. It was used in order to amplify regions of DNA in four species of plants and fungi by polymerase chain reaction (PCR). From plant material of Saccharum officinarum L., Carica papaya L. and Digitalis purpurea L. it was possible to extend different regions of the genome through PCR. Furthermore, it was possible to amplify a fragment of avr-4 gene DNA purified from lyophilized mycelium of Mycosphaerella fijiensis. Additionally, it was possible to amplify the region ap24 transgene inserted into the genome of banana cv. 'Grande naine' (Musa AAA). [ABSTRACT FROM AUTHOR]

The article presents an evaluation of a symposium conducted on the book "Presumed Incompetent: The Intersections of Race and Class for Women in Academia." It mentions that professors of law including Angela Mae Kupenda, Stephanie M. Wildman and Angela Onwuachi-Willig shared their experiences and perspectives at the symposium. It also discusses the difficulties faced by women due to discriminations on basis of sex, race and class and several ways to overcome silence towards similar problems.

African-American and Latino voter turnout during the 2008 and 2012 presidential elections hit record numbers. Polls show that the immigration debate influenced Latino voter turnout and preference. Presidential candidate Barack Obama's voiced support of comprehensive immigration reform strengthened his lead among Latino voters in 2008 and, once in office, his executive policy of granting temporary protection to DREAMers solidified his lead among Latino voters in 2012. Both elections showed the power that minority groups can exert when they vote in support of the same candidate. If the demographic changes continue as currently estimated, African Americans and Latinos will contribute in large part to the making of the United States into a "majority-minority" nation and will play an increasingly important role in local and national politics. Therefore, it is important for Americans to become more inclusive of all minority groups and to expand discussions of race relations beyond the Black-White paradigm and discussions about immigration beyond the Latino-White paradigm. Av the polarized reactions to the Zimmerman verdict showed, there is much work to be done as the people of the United States continue the project of forming "a more perfect Union. Honest assessments of how individuals and groups interact are crucial to opening borders and encouraging exchanges beyond socially constructed boundaries, like race, and racialized politics. African Americans and Latinos often compete with each other for political representation and other resources. In addition, the political consideration of immigration law and policy includes a racial dimension that is often camouflaged, but denial and silence about this reality do nothing to move the country forward. Therefore, immigration provides an opportunity to examine race relations and the potential for inter-group coalitions between African Americans and Latinos. For this reason, this Article also explores, through the lens of immigration, the role that race may play in the attitudes of African Americans and Latinos toward each other. One of the goals of this Article is to spark a candid dialogue that promotes a better understanding of race and its impact on interactions between African Americans and Latinos in the United States. [ABSTRACT FROM AUTHOR]

Antibiotic and herbicide resistance genes have been used in transgene technology as powerful selection tools. Nonetheless, once transgenic events have been obtained their presence is no longer needed and can even be undesirable. In this work, we have developed a system to excise the selectable marker and the cre recombinase genes from transgenic banana cv. 'Grande Naine' ( Musa AAA). To achieve this, the embryo specific REG- 2 promoter was isolated from rice and its expression pattern in banana cell clumps, somatic embryos and regenerated plantlets was characterized by using a pREG2::uidA fusion construct. Subsequently, the REG- 2 promoter was placed upstream of the cre gene, conferring Cre functionality in somatic embryos and recombination of lox sites resulting in excision of the selectable marker and cre genes. PCR analysis revealed that 41.7 % of the analysed transgenic plants were completely marker free, results that were thereafter confirmed by Southern blot hybridization. These results demonstrate the feasibility of using developmentally controlled promoters to mediate marker excision in banana. This system does not require any extra handling compared to the conventional transformation procedure and might be useful in other species regenerating through somatic embryogenesis. [ABSTRACT FROM AUTHOR]

The article discusses U.S. immigration law and the role of judicial discretion in the removal of lawful permanent residents as of March 2012, focusing on the U.S. Supreme Court case United States v. Booker which deals with the nation's Sentencing Guidelines and reportedly returned judicial discretion back to the federal judges. The relationship between immigration law and removal (deportation) is analogized with the relationship between criminal law and punishment.

Abstract: Tuta absoluta (Meyrick) resistance to insecticides has become a significant problem in many tomato production areas in South America. New insecticides are now available for the management of this pest (i.e. spinosad), however there is scarce information about their efficacy on field populations. With the aim of determining the susceptibility of T. absoluta to spinosad we evaluated the response of second instar larvae, from five field populations (Azapa 1, Azapa 2, Lluta, Colín and Valdivia) and a laboratory reference strain (S), to a diagnostic concentration of the insecticide. We also determined the activity of the detoxifying enzymes mixed-function oxidases (MFO), glutathione-S-transferases (GST) and esterases (EST) in the same larval stage. Larval mortality in field populations was significantly lower in Azapa 1 (50.0%), Azapa 2 (44.9%), Lluta (39.9%) and Colín (53.5%) when compared to the laboratory strain (91.7%). MFO activities in field populations were between 1.8 and 4.6 times higher than those observed in the S strain, while for EST, the ratio varied from 1.7 to 14.7. The lowest ratios were observed for the GST (0.5–2.7), however, significant differences were detected for the three enzyme systems. We conclude that the evaluated mechanisms would be involved in spinosad resistance of populations of T. absoluta, presenting an increased MFO activity in all populations. [Copyright &y& Elsevier]

Abstract: Despite the frequent and widespread applications of organophosphates against Cydia pomonella this species has developed low levels of resistance to this chemical group. Investigations concerning the mechanisms involved in resistance are scarce, and usually consider only one of the potential mechanisms. With the aim of a better understanding the resistance mechanisms and their possible interaction, four of these mechanisms were investigated simultaneously in one sensitive (Sv) and two resistant strains (Raz and Rdfb) of this insect. Resistant strains displayed an increased mixed function oxidase activity, whereas carboxylesterase activity varied upon the substrate used. The three strains had similar β-naphtyl acetate activity, and the hydrolysis of α-naphthyl acetate and p-nitrophenyl valerate was higher in the Sv strain. The p-nitrophenyl acetate activity was highest in the resistant strains and was strongly inhibited by azinphos and DEF. The Raz strain has a modified acetylcholinesterase (AChE), which resulted in a 0.7-, 3.2- and 21.2-fold decrease in the susceptibility to chlorpyriphos-ethyl-oxon, azinphos-methyl-oxon, and paraoxon-methyl, respectively. These combined resistance mechanisms only conferred to Raz a 0.6-, 7.9- and 3.1-fold resistance to the related insecticides. Organophosphates resistance in C. pomonella results from a combination of mechanisms including modified affinities to carboxylesterase substrates, and increased metabolisation of the insecticide. The apparent antagonism between increased functionalisation and reduced sensitivity of the AChE target is discussed. [ABSTRACT FROM AUTHOR]

Genetic breeding of bananas by genetic transformation requires an efficient selection system. One of the selection markers most widely used is the bar gene from Streptomyces hygroscopicus, which encodes phosphinothricin acetyltransferase and confers resistance to phosphinothricin and glufosinate-ammonium, the active ingredients in several commercial herbicides such as BASTA®, Finale® and Liberty®. The present investigation was aimed to determine the minimum lethal concentration of glufosinate-ammonium (Finale®) on embryogenic cell aggregates, in vitro cultured shoots and plants grown in greenhouse of banana cv. 'Grande naine' (Musa AAA). Different concentrations of this herbicide were used in the culture embryogenic cell clusters (5.0, 10.0, 15.0, 20.0, 25.0 mg l-1), in vitro cultured shoots (0, 1.0, 1.5, 2.0, 3.0, 4.0 mg l-1). This was also applied to the foliage of plants in greenhouse (0, 5.0, 10.0, 20.0, 30.0, 40.0 g l-1). Results showed that the minimum lethal concentration in embryogenic cell clusters was 20.0 mg l-1 glufosinate ammonium,in in vitro shoots 3.0 mg l-1 and in plants in greenhouse 30.0 g l-1. Results also demonstrated that the use of glufosinate ammonium as a selective agent of transformants carrying the bar gene is possible. [ABSTRACT FROM AUTHOR]

The article reports on the resistance monitoring in codling moth. It discusses that the resistance to azinphosmethyl, methoxyfenozide and lambda-cyhalothrin was associated with reduced residual activity in the field. It infers that the codling moth is one of the primary pests in the world. It is also inferred that the broad-spectrum resistance presents serious problems for management of the codling moth in Michigan. In addition. apple plots were treated with labeled with labeled field rate doses of four insecticides.

The article presents a discussion which calls for fairness and responsibility in the administration of immigration law in the U.S. According to the article, immigrants have made important contributions in he country, through imparting their skills and knowledge to the society. In addition, the author relates that it is important to have fairness and equality among citizens in the state.

The article presents a study which underscores the diversity of insecticide resistance mechanisms and spectrum in European populations of the Cydia pomonella L. It is forwarded that only a few of the registered insecticides against Cydia pomonella L. are still efficient in areas where insecticide resistance has appeared in the past. In this study, the efficacy of ten insecticides was examined along with the resistance mechanisms expressed in four laboratory strains and 47 field populations of C. pomonella from five countries. It is found that all populations showed a lessened susceptibility to at least one insecticide when compared with the susceptible laboratory strain.

Regular applications of insecticides have been the main management practice against codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae) in Chile. Organophosphates are the most widely used insecticides, and azinphos-methyl is an important element in spray programs. In particular, we evaluated diagnostic doses of azinphos-methyl on neonate and postdiapausing larvae from seven apple (Malus spp.) orchards. We also evaluated the activity of detoxifying enzymes, such as glutathione S-transferases (GSTs), cytochrome P450 polysubstrate monooxygenases (PSMOs), and esterases, which are likely to be involved in resistance to insecticides. Such responses were compared with an insecticide-susceptible strain that has been maintained in the laboratory for several years. Neonate larval mortality of field populations to azinphos-methyl was not significantly different from of the susceptible strain. In contrast, postdiapause larval mortality was significantly lower in the six analyzed populations than in the susceptible strain. The C. pomonella populations with reduced postdiapause mortality to azinphos-methyl also showed statistically higher GST activity. Finally, no significant differences were found in total esterase or PSMO activity between C. pomonella populations. Therefore, the observed reduction in postdiapause larval mortality to azinphos-methyl seems to be associated with an increase in GST activity. [ABSTRACT FROM AUTHOR]

Abstract: Two strains of Cydia pomonella (L.) (Lepidoptera: Tortricidae) were selected in the lab by exposure to increasing concentrations of diflubenzuron (Rdfb strain) or azinphos-methyl (Raz strain). Insecticide bioassays showed that the adults of the Rdfb strain exhibited a 2.6-fold and a 7.7-fold resistance ratio to azinphos-methyl and carbaryl, respectively compared to a susceptible strain (S) whereas the adults of the Raz strain exhibited a 6.7-fold resistance ratio to azinphos-methyl and a 130-fold resistance ratio to carbaryl. In the Raz strain, a target site resistance mechanism was suggested by the inhibition of acetylcholinesterase (AChE) activity. In fact the ki values did not discriminate the S and Rdfb strains, while the Raz strain exhibited a 1.7-fold and a 14-fold increase in ki value compared to the S strain for azinphos-methyl oxon and carbaryl, respectively. To verify this hypothesis, two cloned AChE cDNAs sequences (named cydpom-ace2 e cydpom-ace1) were compared between the susceptible and the resistant strains. No difference in the deduced amino acid sequence was found in cydpom-ace2 (orthologous to the Drosophila melanogaster AChE). In the putative cydpom-ace1 (paralogous to the Drosophila AChE), a single amino acid substitution F399V was exclusively present in the Raz strain. The F399 lined the active site of the enzyme and the F399V substitution likely could influence the accessibility of different types of inhibitors to the catalytic site of the insensitive cydpom-ace1. [Copyright &y& Elsevier]

The Lepidopteran pest of tomato, Tuta absoluta, is native to South America and is invasive in the Mediterranean basin. The species' routes of invasion were investigated. The genetic variability of samples collected in South America, Europe, Africa and Middle East was analyzed using microsatellite markers to infer precisely the source of the invasive populations and to test the hypothesis of a single versus multiple introductions into the old world continents. This analysis provides strong evidence that the origin of the invading populations was unique and was close to or in Chile, and probably in Central Chile near the town of Talca in the district of Maule. [ABSTRACT FROM AUTHOR]

Somatic embryogenesis is a useful process for clonal propagation and genetic improvement by induction of mutations. This work was carried out with the objective of determining the effect of 60Co source Gamma radiations on embryogenic cell suspensions of banana cv. 'Grande naine' (Musa AAA) until conversion to plants. Different doses of radiation (0, 30, 40, 50, 60, 70 and 80 Gy) were applied to embryogenic cell suspensions in the multiplication phase and the embryos were later formed, matured and germinated. To determine the ex vitro response of the population of plants obtained these were transferred to greenhouse. The results showed that with somatic embryos formed fresh mass no differences were observed between the effect of the different doses of radiation applied and the control. However, the radiation dose affected the percentage of somatic embryo formation and germination. Plants with phenotypic variations were regenerated with 40 Gy. The results at the greenhouse showed that as radiation doses increasedup to 50 Gy, the frequency of variations increased. With higher doses of radiation the survival of the plants was affected. [ABSTRACT FROM AUTHOR]

Bananas and plantains are grown in tropical and subtropical regions of the world. These plants required high humid conditions; therefore water deficit affects their growth and productivity. Through biotechnology, new drought tolerant genotypes could be obtained. These genotypes can be selected from in vitro culture by adding osmo-stressor agents to the media. The aim of this work was to determine the response of in vitro banana plants cv. 'Grande naine' (Musa AAA) to water stress induced by polyethylene glycol. Morphological (height and number of shoots per explant), physiological (total chlorophyll and relative water chlorophyll contents) and biochemical (proline, malondialdehyde and hydrogen peroxide contents) traits of water stress were determined on stressed and unstressed plants. On stressed plants, a decrease in height and number of shoots per explant, and the increase in proline and malondialdehyde contents were observed. However, total chlorophyll, hydrogen peroxide and relative water contents were not affected. These findings showed that polyethylene glycol can be used as osmo-stress inducer for in vitro selection of drought tolerant banana plants. [ABSTRACT FROM AUTHOR]

The somatic embryogenesis response is close linked with the development phase of the explant donor plant. Therefore, the objective of this work was to determine the effect of male flower position in the plant on the embryogenic responses in plantain cv. 'FHIA-21' (Musa AAAB). In this study male flower were collected at 0, 10, 20 and 30 cm from the last female flower. After 20 weeks on culture, the number of callus with somatic structures was evaluated. Thereafter, the effect of the callus morphology in the establishment of embryogenic cell suspensions was assessed. The results showed that the development phase of immature male flower (measured by the distance to the last female flower) was an important factor on the embryogenic callus induction. The best response on embryogenic callus formation (8.77%) was obtained with explants collected just after the last female flower (0 cm). Although, it was possible to assess that 85.0% of the callus composed by pro-embryogenic masses and somatic embryos in the early stage of its ontogeny development, resulted in embryogenic cell suspensions with the major volume of settled cell aggregated. As a result, it was possible to conclude that the age of the male flower play an important role on the somatic embryogenic process in plantain cv. 'FHIA-21'. [ABSTRACT FROM AUTHOR]

Abstract: Selectable marker genes are indispensable for efficient production of transgenic events, but are no longer needed after the selection process and may cause public concern and technological problems. Although several gene excision systems exist, few have been optimized for vegetatively propagated crops. Using a Cre-loxP auto-excision strategy, we obtained transgenic banana plants cv. Grande Naine (Musa AAA) devoid of the marker gene used for selection. We used T-DNA vectors with the cre recombinase gene under control of a heat shock promoter and selectable marker gene cassettes placed between two loxP sites in direct orientation, and a gene of interest inserted outside of the loxP sites. Heat shock promoters pGmHSP17.6-L and pHSP18.2, from soybean and Arabidopsis respectively, were tested. A transient heat shock treatment of primary transgenic embryos was sufficient for inducing cre and excising cre and the marker genes. Excision efficiency, as determined by PCR and Southern hybridization was 59.7 and 40.0% for the GmHSP17.6-L and HSP18.2 promoters, respectively. Spontaneous excision was not observed in 50 plants derived from untreated transgenic embryos. To our knowledge this is the first report describing an efficient marker gene removal system for banana. The method described is simple and might be generally applicable for the production of marker-free transgenic plants of many crop species. [Copyright &y& Elsevier]

The most important papaya variety in Cuba is Red Maradol. However, it is susceptible to the main viral diseases that attack this crop. For this reason, it is necessary to establish a method for plant regeneration via somatic embryogenesis as the base to develop a protocol for genetic transformation to obtain resistant plants. The objective of this work was to obtain somatic embryos of papaya Red Maradol starting from zygotic embryos. The effect of different factors in somatic embryogenesis and plant regeneration, starting from immature zygotic embryos, was evaluated. The somatic embryos were obtained in a culture medium MS with 5 mg.l-1 2,4-D. Also, the use of 2 mg.l-1 of this plant growth regulator had a positive effect in the secondary multiplication of somatic embryos. The addition of 5 mg.l-1 AIB favored the buds rooting (78.0%), but its longitude was inferior to 1.85 cm. The culture of buds in liquid elongation medium allowed them to reach an average longitude of 3.05 cm and 4.50 leaves, which permitted its appropriate survival in the acclimatization phase. [ABSTRACT FROM AUTHOR]

Comparison of two methods for the establishment of embryogenic cell suspensions obtained from the culture of male flower directly in liquid culture medium and embryogenic callus of banana cv. 'Grande naine' (Musa AAA) was studied in this work. Establishment of homogeneous embriogenic cell suspensions from the culture of both explants in liquid medium was achieved though floral bud range eight showed the best results. Differences in the growing of cell suspension, somatic embryos formation and germination was not observed when the suspensions were compared. Nevertheless the methodology proposed in this work was faster than the 'callus' methodology and percentage of establishment was higher. [ABSTRACT FROM AUTHOR]

The present work had the objective of determining the minimum lethal doses of the selective agent phosphineotricine, to establish the adequate conditions for the selection of genetically transformed cellular embryogenic aggregates of banana cultivar Grande Naine. Schenk and Hildebrandt culture medium, modified by Bieberach, was used , adding different concentrations of the selective agent at (0, 3, 6, 9 and 12 mg ·l-1). The evaluation of the survival of the explants was carried out visually to the 30 days of culture using the scale elaborated in this work, as well as the cellular vitality for staining with Diacetate of Fluoresceine (DAF). The concentrations of the selective agent used, were the cause of the plant cells death. This effect was increased when increasing the concentration and the time of exposition from the vegetable material to the culture medium with the selective agent (increase of the toxicity). The minimal lethal doses selected was 6 mg·l-1 because the total necrosis in the banana cells and death of the tissue produced when was observed to the microscope the vitality of the cellular aggregates. [ABSTRACT FROM AUTHOR]

Sugarcane (Saccharum spp.) is a crop of great economic importance that has been propagated by tissue culture through organogenesis and somatic embryogenesis. The present research had as objective to determine the phenotypic variability in the field of sugar cane cv. 'C87-51' plants obtained by somatic embryogenesis in liquid culture media. Plants regenerated from somatic embryos were planted in the field next to plants propagated via organogenesis and from cuttings that were used as control. The evaluations were carried out seven months after planting in cane plant and first shoot and the variables evaluated were stem height, stem diameter, number of stems per seedlings, number of active leaves per stem and Brix. Besides, morphological characteristics were described. Plants out of type were not found in the evaluated populations. The results demonstrated that the plant regeneration pathway significantly influences the development of plants under field conditions. The propagation of sugarcane plants cv. 'C87-51' by somatic embryogenesis in liquid culture medium only induces phenotypic changes in field associated with in vitro rejuvenation similar to those previously reported for plants obtained by organogenesis. Therefore, it can be used as a method of mass propagation of plants. [ABSTRACT FROM AUTHOR]

Abstract: The codling moth Cydia pomonella L. is controlled mostly with chemical insecticides in Greece and control failures have been reported. However, there are no insecticide resistance studies in the country as yet. We examined the insecticide resistance status of 33 and 38 populations of fifth-instar non-diapausing and diapausing larvae, respectively by applying bioassays, biochemical and DNA diagnostics. Diagnostic concentrations of azinphos-methyl, phosalone, deltamethrin, thiacloprid, fenoxycarb, tebufenozide, methoxyfenozide and diflubenzuron were used in bioassays. Almost all populations showed reduced susceptibility to at least one insecticide and approximately half of them to all insecticides examined compared to a laboratory susceptible strain used as reference. However, only one out of six populations tested showed reduced susceptibility in ovicidal tests with fenoxycarb. Cross-resistances were observed among most insecticides, except from the pairs fenoxycarb–phosalone and thiacloprid–phosalone, in non-diapausing larvae. The more obvious biochemical marker associated with the reduced susceptibility observed in both larval instars was elevated cytochrome P450 polysubstrate monooxygenases activity, followed by elevated glutathione-S-transferase activity and reduced carboxylesterases activity. Neither sodium channel nor AChE known resistance mutations were found in any of the approximately 1000 individuals of each larval instar screened with diagnostic PCR. Actions for Integrated Resistance Management and application of alternative control methods are discussed. [Copyright &y& Elsevier]

Somatic embryogenesis (SE) has been developed in several species of plants with different objectives. Even though, the mass production of plants and the evaluation of field behaviour in big populations been achieved in few cases. Somatic embryogenesis has been developed in some cultivars of Musa spp. to facilitate protocols of genetic transformation. Though, this technique can be an alternative to increase the efficiency for mass production of in vitro plants to commercially scale for cultivation in productive areas. The aim of this paper was to determine the field behaviour of dwarf Cavendish plants obtained by somatic embryogenesis. The evaluations were carried out about the stability of the some morphological and quantitative characters of the plants related to the yield components were evaluated. The agricultural yield, under production conditions, of this plants compared to plants derived from suckers, conventionally cultured, was also determined. Results indicated that plants obtained by SE presented very few indexes of morphological variation in both productive cycles. The agricultural yield was superior with regard to the plants obtained by suckers in both cycles. Results of a population evaluated of more than 5 000 plants, obtained by SE in the cultivar 'Dwarf Cavendish', constituted a reliable evidence to recommend this method as a viable alternative for the in vitro mass propagation of plants in this cultivar. [ABSTRACT FROM AUTHOR]

The season of the year is one of the possible factors to consider for taking the initial explants to develop somatic embryogenesis. This work was carried out to determine the influence of the season of the year on the callus with embryogenic structures formation, in the banana cultivar 'Grande naine' (Musa AAA) to collect immature male inflorescences are. Male inflorescences were collected for three years, every month. Nodal fascicles closest to the floral meristem were extracted and placed in semisolid medium. The number of contaminated explants and the embryogenic response for each time was quantified, six months after culture. The percentage of microbial contamination and the percentage of fascicles that formed callus with high frequency somatic embryogenesis were calculated using these data. In addition, it the relationship of these variables with the values of average temperatures and precipitations during the three years were also studied. The percentages of contamination were highly variable depending on the season of the year in which the inflorescences were collected in the field (0 - 82.5%). The analysis did not show correlation between embryogenic response and percentage of contamination, in relation to rainfall and temperature values recorded during the three years of research. Embryogenic response ranged from 0-11.5%. Results showed that the season of the year to collect immature male inflorescences did not influence the formation of somatic embryos in this cultivar of banana. [ABSTRACT FROM AUTHOR]

The present work was carried out with the objective to obtain plantain transgenic plants of 'Navolean' (Musa AAB) cultivar and to evaluate them, under field conditions during the first crop cycle, for Black Sigatoka disease. Embryogenic cell suspensions obtained from scalp were used for the transformation by Agrobacterium tumefaciens. The bacterial strain EHA-105 was used with the binary plasmid pHGA-91, which contained a combination of genes that encode for the antifungal glucanase enzyme and the AP24 osmotin. Twenty putative transformed lines of the construct were obtained after two months of selection in the culture medium. The transgenic events were verified by means of PCR and Southern hybridisation. These confirmed the stable integration and expression of the transgenes in transgenic plants that were selected in field showing differences with non-transgenic plants used as control. [ABSTRACT FROM AUTHOR]

Plant regeneration protocols are a requirement to develop plants transformation systems.The capacity of Phaseolus acutifolius A. Gray to regenerate plants from embryogenic callus formation was investigated. Two explants were used to form calli on a culture medium containing thidiazuron and indole-3-acetic acid. The embryonic axes showed better capacity than cotyledons to form embryos. Solar light was the most favourable to develop the in vitro plants. The 32% of somatic embryos with complete germination was achieved. These results indicate that somatic embryos formation and their germination in Phaseolus acutifolius A. Gray depended on the explant, culture medium and illumination conditions. In vitro-germinated plantlets were established in the greenhouse. [ABSTRACT FROM AUTHOR]

The study aimed to develop somatic embryo (Es) formation of cv. 'FHIA-21' (Musa AAAB) in a liquid culture medium, based on embryogenic cell suspensions. Four inoculation densities (0.5, 1.0, 1.5 and 2.0g of fresh mass (GMF) of embryogenic cell aggregates) in 250 ml Erlenmeyer capacity, which contained 30 ml of culture medium, were studied. Evaluations were made within 30 days of culture. The following variables were identified: number of Es, length (mm), and morphological and histological features. Results showed the regulatory effect of inoculation density on the formation and morphological development of Es. In this sense, the low density (0.5 and 1.0 GMF) brought about a lower amount of ES, which was larger and with more advanced ontogenetic development. However, the high density of inoculation (1.5 and 2.0 GMF) produced a larger number of uniform size Es and in the globular stage. [ABSTRACT FROM AUTHOR]

The acclimatization stage of in vitro cultured papaya (Carica papaya L.) remains one of the main problems. This study evaluated the influence of the type of cover and length of in vitro plants on their survival in the acclimatization phase. Plants of papaya, variety red Maradol, obtained by somatic embryogenesis were used. An 80% survival rate was reached using a nylon and mesh cover. Results demonstrated that in vitro plants should be transferred to greenhouse conditions larger than 3 cm and with taproot present. This is a decisive influence on the development of plants in ex vitro conditions. [ABSTRACT FROM AUTHOR]

Somatic embryogenesis in papaya has been subjected to much research. However, the effect of ex vitro and in vitro environments on this process has been little studied. The objectives of this work were to determine the influence of the seasons for fruit harvest on the formation of papaya somatic embryo stage, based on zygotic embryos of immature fruits and the effect of the kind of culture flask on the formation and germination of somatic embryo stages. Results demonstrated that the season for the collection of immature fruits did not influence the formation of somatic embryos. Besides the use of glass culture flasks allowed to obtain 63.7% of embryos that developed zygotic embryos. The best results were achieved using this kind of culture flask, with a 90.7% germination of somatic embryos. [ABSTRACT FROM AUTHOR]