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OBJECTIVES: This study sought to explore and externally validate the Carpenter instrument's efficacy in predicting postdischarge fall risk among older adults admitted to the emergency department (ED) for reasons other than falls or related injuries. METHODS: A prospective cohort study was conducted on 779 patients aged ≥ 65 years from a tertiary hospital in São Paulo, Brazil, who were monitored for up to 6 months post-ED hospitalization. The Carpenter instrument, which evaluates the four risk factors nonhealing foot sores, self-reported depression, inability to self-clip toenails, and prior falls, was utilized to assess fall risk. Follow-up by telephone occurred at 30, 90, and 180 days to identify falls and mortality. Fine-Gray models estimated the predictive power of Carpenter instrument for future falls, considering death as a competing event and sociodemographic factors, frail status, and clinical measures as confounders. RESULTS: Among 779 patients, 68 (9%) experienced a fall within 180 days post-ED admission, and 88 (11%) died. The majority were male (54%), with a mean age of 79 years. Upon utilizing the Carpenter score, those with a higher fall risk (≥2 points) displayed more comorbidities, greater frailty, and increased clinical severity at baseline. Regression analyses showed that every additional point on the Carpenter score increased the hazard of falls by 73%. Two primary contributors to its predictive potential were identified: a history of falls in the preceding year and an inability to self-clip toenails. However, the instrument's discriminative accuracy was suboptimal, with an area under the curve of 0.62. CONCLUSIONS: While the Carpenter instrument associated with a higher 6-month postadmission fall risk among older adults post-ED visit, its accuracy for individual patient decision making was limited. Given the significant impact of falls on health outcomes and health care costs, refining risk assessment tools remains essential. Future research should focus on enhancing these assessments and devising targeted proactive strategies.

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Background: Emergency medical services (EMS) and critical care transport crews constantly face critically-ill patients who need ventilatory support in scenarios where correct interventions can be the difference between life and death; furthermore, challenges like limited staff working on the patient and restricted spaces are often present. Due to these, mechanical ventilation (MV) can be a support by liberating staff from managing the airway and allowing them to focus on other areas; however, these patients face many complications that personnel must be aware of. Aims: To establish the main complications related to out-of-hospital MV and ventilatory support through a systematic review. Methodology: PubMed, BVS and Scopus were searched from inception to July 2021, following the PRISMA guidelines; search strategy and protocol were registered in PROSPERO. Two authors carried out an independent analysis of the articles; any disagreement was solved by mutual consensus, and data was extracted on a pre-determined spreadsheet. Only original articles were included, and risk of bias was assessed with quality assessment tools from the National Institutes of Health. Results: The literature search yielded a total of 2,260 articles, of which 26 were included in the systematic review, with a total of 9,418 patients with out-of-hospital MV; 56.1% were male, and the age ranged from 18 to 82 years. In general terms of aetiology, 12.2% of ventilatory problems were traumatic in origin, and 64.8% were non-traumatic, with slight changes between out-of-hospital settings. Mechanical ventilation was performed 49.2% of the time in prehospital settings and 50.8% of the time in interfacility transport settings (IFTS). Invasive mechanical ventilation was used 98.8% of the time in IFTS while non-invasive ventilation was used 96.7% of the time in prehospital settings. Reporting of adverse events occurred in 9.1% of cases, of which 94.4% were critical events, mainly pneumothorax in 33.1% of cases and hypotension in 27.6% of cases, with important considerations between type of out-of-hospital setting and ventilatory mode; total mortality was 8.4%. Conclusion: Reported adverse events of out-of-hospital mechanical ventilation vary between settings and ventilatory modes; this knowledge could aid EMS providers in promptly recognizing and resolving such clinical situations, depending on the type of scenario being faced.

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The symbiotic N2-fixation process in the legume-rhizobia interaction is relevant for sustainable agriculture. The characterization of symbiotic mutants, mainly in model legumes, has been instrumental for the discovery of symbiotic genes, but similar studies in crop legumes are scant. To isolate and characterize common bean (Phaseolus vulgaris) symbiotic mutants, an ethyl methanesulphonate-induced mutant population from the BAT 93 genotype was analyzed. Our initial screening of Rhizobium etli CE3-inoculated mutant plants revealed different alterations in nodulation. We proceeded with the characterization of three non-nodulating (nnod), apparently monogenic/recessive mutants: nnod(1895), nnod(2353) and nnod(2114). Their reduced growth in a symbiotic condition was restored when the nitrate was added. A similar nnod phenotype was observed upon inoculation with other efficient rhizobia species. A microscopic analysis revealed a different impairment for each mutant in an early symbiotic step. nnod(1895) formed decreased root hair curling but had increased non-effective root hair deformation and no rhizobia infection. nnod(2353) produced normal root hair curling and rhizobia entrapment to form infection chambers, but the development of the latter was blocked. nnod(2114) formed infection threads that did not elongate and thus did not reach the root cortex level; it occasionally formed non-infected pseudo-nodules. The current research is aimed at mapping the responsible mutated gene for a better understanding of SNF in this critical food crop.

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OBJECTIVE: To explore trends and patterns of laypeople's activity for seeking telephone number of emergency medical services (EMS) based on analysis of online search traffic, including changes of the search activity with onset of the coronavirus disease 2019 (COVID-19) outbreak, in five countries - the United States of America (USA), India, Brazil, the United Kingdom (UK) and Russia. METHODS: Google Trends (GT) country-level data on weekly relative search volumes (RSV) for top queries to seek EMS number were examined for January 2018-October 2021, including a comparison of RSVs between pre-COVID-19 period (January 2018-October 2019) and COVID-19 period (January 2020-October 2021), and evaluation of temporal associations of RSVs with weekly numbers of new COVID-19 cases. RESULTS: The countries demonstrated diverse patterns of the search activity with significantly different mean RSVs (the USA 1.76, India 10.20, Brazil 2.51, the UK 6.42, Russia 56.79; p < 0.001). For all countries excepting the USA mean RSVs of the COVID-19 period were significantly higher compared with the pre-COVID-19 ones (India +74%, Brazil +148%, the UK +22%, Russia +9%; p ≤ 0.034), and exhibited positive correlations with numbers of new COVID-19 cases, more pronounced for 2021 (India rS = 0.538, Brazil 0.307, the UK 0.434, Russia 0.639; p ≤ 0.045). CONCLUSION: Laypeople's activity for seeking EMS telephone number greatly varies between countries. It clearly responds to the spread of COVID-19 and could be reflective of public need for obtaining emergency help. Further studies are required to establish the role of GT for conducting real-time surveillance of population demand for EMS.

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BACKGROUND: Despite a significant burden of injury-related deaths, the Plurinational State of Bolivia (Bolivia), a lower- middle-income country in South America, lacks a formalized trauma system. This study sought to examine Bolivian trauma care from the patient perspective in order to determine barriers to care and targets for improvement. METHODS: Investigators conducted 15 semi-structured interviews with trauma patients admitted at four hospitals in Santa Cruz de la Sierra, Bolivia in June and July of 2016. Interviews were transcribed, translated, and analyzed through content and discourse analysis to identify key themes and perceptions of trauma care. RESULTS: Participants primarily presented with orthopedic injuries due to road traffic incidents and falls. Only one participant reported receiving first aid from a layperson at the scene of injury. Of the 15 participants, 12 did not know any number to contact emergency medical services (EMS). Participants expressed negative views of EMS as well as concerns for slow response times and inadequate personnel and training. Two thirds of participants were initially brought to a hospital without adequate resources to care for their injuries. Participants generally expressed positive views regarding healthcare workers involved in their hospital-based medical care. CONCLUSIONS: This region of Bolivia has a disorganized, underutilized, and distrusted trauma system. In order to increase survival, interventions should focus on improving prehospital trauma care. Potential interventions include the implementation of layperson trauma first responder courses, the establishment of a medical emergency hotline, the unification of EMS, the implementation of basic training requirements for EMS personnel, and public education campaigns to increase trust in EMS.

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Introduction: San Diego has one of the busiest international land border crossings in the world. The epidemiology of prehospital care at the San Diego (California, USA)-Tijuana (Baja California, Mexico) border crossings are previously unreported. Investigators sought to describe prehospital care provided at the San Diego border crossings. Methods: This was a cross-sectional, retrospective data collection from April 2014 to March 2017 evaluating prehospital provider (PHP) contacts at 2 international border crossing addresses in San Diego. The 9-1-1 dispatch center and first response were provided by a single municipal fire agency with ambulance transportation provided by a contracting private agency. Patient dispatch data and electronic patient care records were queried for patient demographics, PHP arrival time, incident complaint, assessment narrative, and treatments provided. Natural language processing techniques were applied to map the narrative to the National Library of Medicine's Unified Medical Language System. Descriptive analysis was performed in the R software program. Results: A total of 6,261 PHP patient contacts were made at the 2 border crossings during the study period. 87% of the calls were at the San Ysidro border crossing compared to 13% at Otay Mesa. The population, composed of 50.8% males, had ages ranging from 0 days-103 years old, with a median age of 45 years old. There were 606 (9.7%) pediatric patients (<18 years) and 1,416 (22.6%) geriatric patients (>65 years). The top 3 incident complaints were respiratory distress (830, 10.8%), blunt trauma (827, 10.7%), and abdominal pain (814, 10.6%); and, the top 3 medications provided were oxygen (481, 7.7%), normal saline (393, 6.3%), and ondansetron (352, 5.6%). Conclusion: This was the first study of PHP assessment and care at the San Diego-Tijuana border crossings. We found a large diversity in patient ages. Respiratory distress and blunt trauma were the most frequent complaints and oxygen was the most frequent medication. The busiest day of the week was Sunday, and the busiest month of the year was July. Our newly described findings may assist EMS agencies with optimizing staff, equipment, and training at international border crossings.

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INTRODUCTION: Delays in recognizing stroke during pre-hospital emergency medical system (EMS) care may affect triage and transport time to an appropriate stroke ready hospital and may preclude patients from receiving time dependent treatment. All EMS transports in a large urban area in the stroke belt were evaluated for transport destinations, triage and transport time and stroke recognition following distribution ofan educational training video to local EMS services. HYPOTHESIS: Following video training, local paramedics will improve stroke recognition and shorten triage and transport time to appropriate stroke centers of care. METHODS: A training module (<10 min) containing a stroke triage scenario, instruction on the Cincinnati Prehospital Stroke Score (CPSS) and the Los Angeles Prehospital Stroke Score (LAPSS) and 'where to transport' stroke patients was distributed and viewed by 96 paramedics. Data was collected from February to October 2016. Stroke recognition was determined from one primary stroke center (PSC) hospital's confirmation of EMS delivered patients (Site A). Yearly stroke recognition percentages of 44% from Site A in 2014 were used as baseline. RESULTS: A total of 34,833 emergency 911 response transports were made with a total of 502 (1.4%) suspected strokes identified by paramedics. Median [IQR] triage and transport time for stroke transports was 33 [27-41] min. The PSC hospitals received a 5% increase in stroke transports and non-specific care facilities decreased by 7%. From 8,554 transports to site A (PSC) confirmed strokes totalled 107 transports with 139 suspected strokes by paramedics. Of these transports, 60 were correctly identified by paramedics (positive predictive value of 43%, sensitivity of 56%). By the second month following training, recognition percentages increased from baseline to 64%. At five months, percentages of correct stroke identification had dropped to 36%. CONCLUSION: Video based training improved stroke recognition by an additional 19%, but continual monthly or quarterly training is recommended for maintenance of increased stroke recognition.

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Objective: Demographic differences (race/ethnicity/sex) in 9-1-1 emergency medical services (EMS) access and utilization have been reported for various time-dependent critical illnesses along with associated outcome disparities. However, data are lacking with respect to measuring the various components of time taken to reach definitive care facilities following the onset of acute stroke symptoms (i.e., stroke onset to 9-1-1 call, EMS response, time on-scene, transport interval) and particularly with respect to any differences across ethnicities and sex. Therefore, the specific aim of this study was to measure the various time intervals elapsing following the first symptom onset (FSO) from an acute stroke until stroke hospital arrival (SHA) and to delineate any race/ethnic/sex-related differences among any of those measurements. Methods: The Florida-Puerto Rico Stroke Registry (FLPRSR) is an on-going, voluntary stroke registry of hospitals participating in the Get with the Guidelines-Stroke initiative. The study population included patients treated at Florida hospitals participating in the FLPRSR between 2010 and 2014 who had called 9-1-1 and were managed and transported by EMS. In total, 10,481 patients (16% black, 8% Hispanic, 74% white) had complete data-sets that included birthdate/year, sex, ethnic background, date/hour/minute of FSO and date/hour/minute of EMS response, scene arrival, and SHA. Results: Median time from FSO to SHA was 339 minutes (interquartile range [IQR] of 284-442), 301 of which constituted the time elapsed from FSO to the 9-1-1 call (IQR =249-392) versus only 10 from 9-1-1 call to EMS arrival (IQR =7-14), 14 on-scene (IQR =11-18) and 12 for transport to SHA (IQR =8-19). The FSO to 9-1-1 call interval, being by far the longest interval, was longest among whites and blacks (302 minutes for both) versus 291 for Hispanics (p = 0.01). However, this 11-minute difference was not deemed clinically-significant. There were neither significant sex-related differences nor any racial/ethnic/sex differences in the relatively short EMS-related intervals. Conclusions: Following acute stroke onset, time elapsed for EMS response and transport is relatively short compared to the lengthy intervals elapsing between symptom onset and 9-1-1 system activation, regardless of demographics. Exploration of innovative strategies to improve public education regarding stroke symptoms and immediate 9-1-1 system activation are strongly recommended.

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Through a longitudinal field experience and interviews with rural and urban clinic workers in Honduras, the following data were collated regarding the challenges to prehospital Emergency Medical Services (EMS) in this country. In Honduras, both private and public organizations provide prehospital emergency care for citizens and face both financial and resource constraints. These constraints manifest in operational concerns such as challenges of integration of EMS systems with each other, differences in medical direction oversight, and barriers to public access. Despite the availability of public health care services, authorities and locals alike do not recommend using the public systems due to lack of needed resources and time of emergency response.Private volunteer EMS organizations are scattered throughout the country and each operates as their own separate system. There is no single dispatch center available, nor is there a guarantee that calling for EMS will result in the patient's desired response. In this report, the challenges are discussed with possible solutions presented. BastHE, JenkinsJL. Challenges to prehospital care in Honduras. Prehosp Disaster Med. 2018;33(6):637-639.

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5-α-Reductase type 2 enzyme catalyzes the conversion of testosterone into dihydrotestosterone, a potent androgen responsible for male sexual development during the fetal period and later during puberty. Its deficiency causes an autosomal recessive disorder of sex development characterized by a wide range of under-virilization of external genitalia in patients with a 46,XY karyotype. Mutations in the SRD5A2 gene cause 5-α-Reductase deficiency; although it is an infrequent disorder, it has been reported worldwide, with mutational heterogeneity. Furthermore, it has been proposed that there is no genotype-phenotype correlation, even in patients carrying the same mutation. The aim of this review was to perform an extensive search in various databases and to select those articles with a comprehensive genotype and phenotype description of the patients, classifying their phenotypes using the external masculinization score (EMS). Thus, it was possible to objectively compare the eventual genotype-phenotype correlation between them. The analysis showed that for most of the studied mutations no correlation can be established, although the specific location of the mutation in the protein has an effect on the severity of the phenotype. Nevertheless, even in patients carrying the same homozygous mutation, a variable phenotype was observed, suggesting that additional genetic factors might be influencing it. Due to the clinical variability of the disorder, an accurate diagnosis and adequate medical management might be difficult to carry out, as is highlighted in the review.

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Study Objective The aim of this study was to evaluate Emergency Medical Services (EMS), use, injury mechanisms, prehospital assessments, and injuries among those receiving aid from the United States Border Patrol (USBP) in the El Paso (Texas USA) Sector. DESIGN: This is a time-series, retrospective analysis of all prehospital data for injuries among patients receiving care from USBP EMS on the US Mexico border in the El Paso sector from February 6, 2014 to February 6, 2016. RESULTS: A total of 473 documented EMS encounters occurred in this two-year period and demonstrated a male gender predominance (male 63%; female 37%) with the most prominent ages between 22-40 years old. The most prevalent EMS call types were medical (55%) and trauma (42%). The most common chief complaints were an injured or painful extremity (35%) and rash (13%). The most common USBP EMS provider primary impression was traumatic injury (34%), followed by fever/infection (17%) and extremity injury (7%); however, the most common secondary impression was also extremity injury (20%). The most common mechanism of injury was fall (26%) and motor vehicle accident (MVA; 22%). The USBP EMS was the first provider on scene in 96% of the MVAs. CONCLUSION: The author reports on injury patterns, mechanisms, chief complaints, EMS impressions, as well as demographics of patients reporting to USBP EMS. A knowledge of these injury patterns will be useful to EMS administrators and physicians along the US Mexico border. Baker RA . Border injuries: an analysis of prehospital demographics, mechanisms, and patterns of injuries encountered by USBP EMS agents in the El Paso (Texas USA) Sector. Prehosp Disaster Med. 2017;32(4):431-436.

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In shrimp aquaculture, reduction in the use of synthetic antibiotics is a priority due to the high incidence of resistant bacteria (Vibrio) in the white shrimp Litopenaeus vannamei. An increasing number of studies show bactericidal activity of natural treatments in aquaculture. The effectiveness of neem (Azadirachta indica) and oregano (Lippia berlandieri) aqueous extracts and colloidal silver against V. parahaemolyticus were evaluated in low salinity shrimp culture. Results show that aqueous extracts of oregano and neem each present a minimum inhibitory concentration (MIC) of 62.50 mg ml-1 and inhibitory halos of 12.0 to 19.0 mm. Colloidal silver gave a MIC of 2 mg ml-1, and the inhibitory halos were found to be between 11.8 and 18.8 mm, depending on treatment concentrations. An in vivo challenge test was conducted on white shrimp postlarvae cultured at low salinity (5 practical salinity units, PSU), and a significant increase (p < 0.05) in survival was demonstrated in the presence of the aqueous extracts (oregano 64%, neem 76% and colloidal silver 90%), when compared to the control (0%) in the challenge test. However, no significant differences were observed between treatments, suggesting that they all act as alternative bactericidal source agents against V. parahaemolyticus infections for L. vannamei postlarvae when cultured at 5 PSU.

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BACKGROUND: Bystander cardiopulmonary resuscitation (CPR) improves survival after prehospital cardiac arrest. While community CPR training programs have been implemented across the US, little is known about their acceptability in non-US Latino populations. OBJECTIVES: The purpose of this study was to identify barriers to enrolling in CPR training classes and performing CPR in San José, Costa Rica. METHODS: After consulting 10 San José residents, a survey was created, pilot-tested, and distributed to a convenience sample of community members in public gathering places in San José. Questions included demographics, CPR knowledge and beliefs, prior CPR training, having a family member with heart disease, and prior witnessing of a cardiac arrest. Questions also addressed barriers to enrolling in CPR classes (cost/competing priorities). The analysis focused on two main outcomes: likelihood of registering for a CPR class and willingness to perform CPR on an adult stranger. Odds ratios and 95% CIs were calculated to test for associations between patient characteristics and these outcomes. RESULTS: Among 371 participants, most were male (60%) and <40 years old (77%); 31% had a college degree. Many had family members with heart disease (36%), had witnessed a cardiac arrest (18%), were trained in CPR (36%), and knew the correct CPR steps (70%). Overall, 55% (95% CI, 50-60%) indicated they would "likely" enroll in a CPR class; 74% (95% CI, 70-78%) would perform CPR on an adult stranger. Cardiopulmonary resuscitation class enrollment was associated with prior CPR training (OR: 2.6; 95% CI, 1.6-4.3) and a prior witnessed cardiac arrest (OR: 2.0; 95% CI, 1.1-3.5). Willingness to perform CPR on a stranger was associated with a prior witnessed cardiac arrest (OR: 2.5; 95% CI, 1.2-5.4) and higher education (OR: 1.9; 95% CI, 1.1-3.2). Believing that CPR does not work was associated with a higher likelihood of not attending a CPR class (OR: 2.4; 95% CI, 1.7-7.9). Fear of performing mouth-mouth, believing CPR is against God's will, and fear of legal risk were associated with a likelihood of not attending a CPR class and not performing CPR on a stranger (range of ORs: 2.4-3.9). CONCLUSION: Most San José residents are willing to take CPR classes and perform CPR on a stranger. To implement a community CPR program, barriers must be considered, including misgivings about CPR efficacy and legal risk. Hands-only CPR programs may alleviate hesitancy to perform mouth-to-mouth. Schmid KM , Mould-Millman NK , Hammes A , Kroehl M , Quiros García R , Umaña McDermott M , Lowenstein SR . Barriers and facilitators to community CPR education in San José, Costa Rica. Prehosp Disaster Med. 2016;31(5):509-515.

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Response to the 2010 Haitian earthquake included an array of diverse yet critical actions. This paper will briefly review the evacuation of a small group of patients with burns to burn centers in the southeastern United States (US). This particular evacuation brought together for the first time plans, groups, and organizations that had previously only exercised this process. The response to the Haitian earthquake was a glimpse at what the international community working together can do to help others, and relieve suffering following a catastrophic disaster. The international response was substantial. This paper will trace one evacuation, one day for one unique group of patients with burns to burn centers in the US and review the lessons learned from this process. The patient population with burns being evacuated from Haiti was very small compared to the overall operation. Nevertheless, the outcomes included a better understanding of how a larger event could challenge the limited resources for all involved. This paper includes aspects of the patient movement, the logistics needed, and briefly discusses reimbursement for the care provided.

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Terminalia actinophylla has been used for anti-diarrheic and haemostatic purposes in Brazil. The fly spot data obtained after exposure of marker-heterozygous Drosophila melanogaster larvae to T. actinophylla ethanolic extract (TAE) in the standard (ST) and high bioactivation (HB) crosses revealed that TAE did not induce any statistically significant increment in any spot categories. Differences between the two crosses are related to cytochrome P450 (CYPs) levels. In this sense, our data pointed out the absence of TAE-direct and indirect mutagenic and recombinagenic action in the Somatic Mutation and Recombination Test (SMART). When the anti-genotoxicity of TAE was analyzed, neither mitomycin C (MMC) nor ethylmethanesulfonate (EMS) genotoxicity was modified by the post-exposure to TAE, which suggests that TAE has no effect on the mechanisms involved in the processing of the lesions induced by both genotoxins. In the mwh/flr(3) genotype, co-treatment with TAE may lead to a significant protection against the genotoxicity of MMC and a weak but significant effect in the toxic genetic action of EMS. The overall findings suggested that the favorable modulations by TAE could be, at least in part, due to its antioxidative potential.

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OBJECTIVE: To compare medical emergency response plan (MERP) and automated external defibrillator (AED) prevalence and define the incidence and outcomes of sudden cardiac arrest (SCA) in high schools before and after AED legislation. STUDY DESIGN: In 2011, Tennessee Secondary School Athletic Association member schools were surveyed regarding AED placement, MERPs, and on-campus SCAs within the last 5 years. Results were compared with a similar study conducted in 2006, prior to legislation requiring AEDs in schools. RESULTS: Of the schools solicited, 214 (54%, total enrollment 182 289 students) completed the survey. Compared with 2006, schools in the 2011 survey had a significantly higher prevalence of MERPs (84% vs 71%, P < .001), annual practice (56% vs 36%, P < .001), medical emergency communication systems (80% vs 62%, P < .001), and defibrillators (90% vs 47%, P < .001). No differences were noted in the prevalence of cardiopulmonary resuscitation training (20% vs 17%, P = .58) or full compliance with American Heart Association guidelines (11% vs 7%, P = .16). Twenty-two SCA victims were identified, yielding a 5-year incidence of 1 in 10 schools. CONCLUSIONS: After state legislation, schools demonstrated a significant increase in MERPs and on-campus defibrillators but rates of cardiopulmonary resuscitation training and overall compliance with guidelines remained low.

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Hexaploid oat genetic variability was compared in populations treated with physical and chemical mutagens by making a field evaluation of vegetative cycle. Experiments were carried out in two agricultural years in Pelotas, RS (1997/98 and 1998/99). Seeds were irradiated at the UFPel OncoloGy Center, with a dose rate of 0.25Gy min-1. The total absorbed doses for the physical mutagen were 100, 200 and 400Gy and, for the chemical mutagen 0.5, 1.5 and 3.0% per treatment of 1,200 seeds, in each evaluated genotype. A difference in efficiency between mutagens was detected. The physical mutagen was always superior to the chemical mutagen, regardless the generation evaluated, providing a higher increase in the number of phenotypic classes, either leading to a reduction or increase in the number of days between emergence and flowering. The genotypes showed a differential sensitivity to the doses of tested mutagens, indicating a range of treatment efficiency in altering the genetic variability either for early or late vegetative cycle. In general, the results pointed to a decrease in the character vegetative cycle when an increase in the mutagen dose was applied. The study of populations UPF 16 on the doses 100 and 200Gy subjected to treatment with the physical mutagen pointed to a higher degree of genetic divergence and dominance for the character vegetative cycle.

Comparou-se a campo a variabilidade genética em populações de aveia hexaplóide tratadas com agentes mutagênicos físico e químico, através do caráter ciclo vegetativo de plantas. Foram realizados experimentos em duas safras agrícolas em Pelotas, RS, em 1997/98 e 1998/99. As sementes foram irradiadas no Centro Regional de Oncologia da Faculdade de Medicina da UFPel, com uma taxa de dose de 0,25Gy min-1. As doses totais absorvidas para o mutagênico físico foram 100, 200 e 400Gy e, para o mutagênico químico 0,5, 1,5 e 3,0% por tratamento de 1200 sementes aproximadamente, em cada genótipo fixo de aveia avaliado. Foi obtida diferença na eficiência entre os agentes mutagênicos testados. O agente mutagênico físico foi sempre superior em relação ao agente mutagênico químico, independente da geração segregante avaliada, proporcionando assim um incremento maior no número de classes fenotípicas, tanto para redução quanto para o aumento do número de dias entre a emergência e o florescimento. Os genótipos mostraram sensibilidade diferenciada em relação à dose dos agentes mutagênicos avaliados, indicando que a eficiência dos tratamentos em alterar a variabilidade genética para precocidade e aumento do ciclo vegetativo foi variável. De modo geral, os dados indicaram decréscimo do caráter ciclo vegetativo com o acréscimo da dose dos agentes mutagênicos testados. O estudo das populações UPF-16 nas doses 100 e 200 gray submetidas ao tratamento com o agente mutagênico físico apontaram o maior grau de divergência genética e de dominância para o caráter ciclo vegetativo de plantas.

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Hexaploid oat genetic variability was compared in populations treated with physical and chemical mutagens by making a field evaluation of vegetative cycle. Experiments were carried out in two agricultural years in Pelotas, RS (1997/98 and 1998/99). Seeds were irradiated at the UFPel OncoloGy Center, with a dose rate of 0.25Gy min-1. The total absorbed doses for the physical mutagen were 100, 200 and 400Gy and, for the chemical mutagen 0.5, 1.5 and 3.0% per treatment of 1,200 seeds, in each evaluated genotype. A difference in efficiency between mutagens was detected. The physical mutagen was always superior to the chemical mutagen, regardless the generation evaluated, providing a higher increase in the number of phenotypic classes, either leading to a reduction or increase in the number of days between emergence and flowering. The genotypes showed a differential sensitivity to the doses of tested mutagens, indicating a range of treatment efficiency in altering the genetic variability either for early or late vegetative cycle. In general, the results pointed to a decrease in the character vegetative cycle when an increase in the mutagen dose was applied. The study of populations UPF 16 on the doses 100 and 200Gy subjected to treatment with the physical mutagen pointed to a higher degree of genetic divergence and dominance for the character vegetative cycle.

Comparou-se a campo a variabilidade genética em populações de aveia hexaplóide tratadas com agentes mutagênicos físico e químico, através do caráter ciclo vegetativo de plantas. Foram realizados experimentos em duas safras agrícolas em Pelotas, RS, em 1997/98 e 1998/99. As sementes foram irradiadas no Centro Regional de Oncologia da Faculdade de Medicina da UFPel, com uma taxa de dose de 0,25Gy min-1. As doses totais absorvidas para o mutagênico físico foram 100, 200 e 400Gy e, para o mutagênico químico 0,5, 1,5 e 3,0% por tratamento de 1200 sementes aproximadamente, em cada genótipo fixo de aveia avaliado. Foi obtida diferença na eficiência entre os agentes mutagênicos testados. O agente mutagênico físico foi sempre superior em relação ao agente mutagênico químico, independente da geração segregante avaliada, proporcionando assim um incremento maior no número de classes fenotípicas, tanto para redução quanto para o aumento do número de dias entre a emergência e o florescimento. Os genótipos mostraram sensibilidade diferenciada em relação à dose dos agentes mutagênicos avaliados, indicando que a eficiência dos tratamentos em alterar a variabilidade genética para precocidade e aumento do ciclo vegetativo foi variável. De modo geral, os dados indicaram decréscimo do caráter ciclo vegetativo com o acréscimo da dose dos agentes mutagênicos testados. O estudo das populações UPF-16 nas doses 100 e 200 gray submetidas ao tratamento com o agente mutagênico físico apontaram o maior grau de divergência genética e de dominância para o caráter ciclo vegetativo de plantas.

RESUMEN

The most important pest of the cupuaçu crop is the fruit borer, Conotrachelus humeropictus Fiedler (Coleoptera: Curculionidae), wich severely damages fruits and is disseminated all over North Brazil. The objectives of this study were evaluating the population fluctuations of C. humeropictus adults, infestation levels and to characterize the pest larval attack in cupuaçu fruits of agroforestry systems of the Rondonia State, Brazil. Population fluctuations from C. humeropictus adults were evaluated weekly from March/98 to July/00 in twenty cupuaçu plants, by shaking the tree branches, of two producer areas. During two harvest periods, fruits attacked by the borer were collected and examined for evaluation of larvae population. Pest infestation was determined by the percentage of damaged fruits. C. humeropictus adults occur year around on cupuaçu plants, but predominate at the stages of flowering, fruit formation and during the harvest period. It was observed that mature and non-mature fruits are attacked by the pest; larvae of different ages can occur in a same fruit; the insect may cause losses greater than 50% of fruit yield.

Dentre as pragas do cupuaçueiro Theobroma grandiflorum (Wild. ex Spreng.) Schum., a broca-dos-frutos, Conotrachelus humeropictus Fiedler (Coleoptera: Curculionidae), é a mais importante, devido aos danos causados e por estar disseminada em alguns Estados da região Norte do Brasil. Os objetivos deste trabalho foram avaliar a flutuação populacional de adultos de C. humeropictus, determinar a intensidade de infestação e caracterizar o ataque de larvas desta praga em frutos de cupuaçueiros, em sistemas agroflorestais no Estado de Rondônia. Para obter a flutuação populacional de adultos da broca, foram amostradas semanalmente, durante o período de março/98 a julho/00, 20 plantas de cupuaçu, pelo método do sacolejo, em duas áreas de agrossilvicultores. A avaliação da população de larvas foi realizada durante duas safras, onde foram coletados e abertos frutos atacados pela broca. A determinação da infestação da praga foi obtida através da porcentagem de frutos broqueados. Adultos de C. humeropictus ocorrem durante todo ano nas plantas de cupuaçu, na área estudada, mas predominam na floração, início da frutificação e durante o período de safra. Tanto os frutos verdes como os maduros são atacados, sendo que larvas de idades diferentes podem ocorrem em um mesmo fruto. Perdas superiores a 50% na produção de frutos, devido ao ataque da broca, ressaltam a importância desta praga na região.