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Internal clocks drive rhythms in behaviour and physiology in all eukaryotic organisms. The period (per) gene of the fruit fly Drosophila melanogaster controls the period of a ∼24hr locomotor activity rhythm and a ~55 second cycle in the male courtship song. D. melanogaster is one of eight very closely related species which comprise the melanogaster subgroup of Drosophila. The locomotor activity behaviour and courtship songs of several species from the melanogaster subgroup were analysed. Drosophila yakuba was found to have a cycle period of 70-80 seconds in its courtship song - longer than either D. melanogaster (50-60 seconds) or D. simulans (30-40 seconds), two previously characterised members of the subgroup. The period of the locomotor activity rhythms of four members of the subgroup, D. yakuba, D. melanogaster, D. erecta and D. teissieri, were indistinguishable from each other. However, each species exhibited unique patterns of activity within each daily cycle. The D. yakuba per locus was cloned, using the D. melanogaster per gene as a probe. The DNA sequences of two D. yakuba genes were obtained, per itself and a small adjacent gene. A region of the per protein which has been implicated in the control of the song cycle period, a repeating series of threonine glycine pairs, is shorter than in D. melanogaster. A patchy distribution of amino acid replacements was found between the D. melanogaster and D. yakuba per proteins, probably due to differences in selective constraints in different regions of the protein. In an effort to determine whether per determines species-specific aspects of behavioural rhythms, attempts were made to transduce mixed species per gene constructs into arrhythmic (per mutant) strains of D. melanogaster. These attempts were unsuccessful.

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A ferrugem alaranjada da cana-de-açúcar, causada pelo fungo Puccinia kuehnii, é atualmente a doença que mais preocupa o setor sucroenergético brasileiro, devido a sua introdução recente no país e aos prejuízos causados em indústrias canavieiras ao redor do mundo. A doença é controlada com variedades resistentes e por isso há a necessidade de maiores informações sobre a reação das cultivares mais importantes no Brasil. Os objetivos deste trabalho foram: (i) avaliar a reação de variedades de cana-de-açúcar à ferrugem alaranjada, em condições de infecção natural no campo; (ii) determinar a melhor época para avaliação da doença; (iii) estabelecer um método, em casa de vegetação e com inoculação artificial do patógeno, para seleção rápida de variedades com resistência no campo. Dezessete variedades foram avaliadas quanto às suas reações a P. kuehnii em dois experimentos de campo, plantados em abril e julho de 2011; neste último, após a colheita em maio de 2012, a cana-soca também foi avaliada. Para multiplicar e uniformizar a distribuição do inóculo, a variedade suscetível SP89-1115 foi usada como bordadura e plantada entre os blocos e em duas linhas, dividindo cada experimento ao meio. Avaliou-se a severidade da doença a cada 15 dias e, a partir destes dados, calculou-se a área abaixo da curva de progresso da doença (AACPD) e obteve-se a severidade máxima da doença. Para identificar o melhor período de avaliação, realizou-se análise de correlação entre a AACPD e cada levantamento de severidade. Em casa de vegetação, seis variedades com reações distintas à doença, com base nos resultados obtidos no campo, foram inoculadas com uma suspensão de 104 urediniósporos viáveis mL-1 de P. kuehnii, com auxílio de pulverizador manual, 60 dias após o plantio. As plantas foram mantidas por 24 horas em câmara de orvalho e, posteriormente, transferidas para casa de vegetação. Foram determinados os períodos de incubação e latência, o número de pústulas por cm2 e a severidade da doença. Oito das 17 variedades avaliadas no campo mostraram alta resistência à doença. As cultivares RB72454 e SP89-1115 foram as mais suscetíveis, seguidas da SP79-2233; por isso, o cultivo das mesmas não é recomendado. As variedades RB925211, SP81-3250, RB855156 e RB92579 tiveram reação intermediária, sendo que as duas primeiras apresentaram maiores níveis da doença. Avaliações realizadas no mês de março foram as que mais se correlacionaram com a AACPD, portanto este é o melhor período para determinar a reação de variedades de cana-de-açúcar à ferrugem alaranjada. O comportamento das variedades em casa de vegetação foi semelhante ao observado no campo, especialmente em relação às cultivares suscetíveis e resistentes. Assim, o método aplicado em casa de vegetação mostrou potencial para selecionar, em poucos dias, cultivares com resistência à doença no campo, além de economizar espaço, mão de obra e de ser facilmente executado. / Currently, sugarcane orange rust, caused by Puccinia kuehnii, is the disease that most concerns the Brazilian sugarcane industry, due to its recent introduction in the country and the damage caused to sugarcane industries all over the world. The disease is controlled with resistant varieties; hence there is a need for more information about the reaction of the major cultivars in Brazil. The objectives of this work were: (i) to evaluate the reaction of sugarcane varieties to orange rust in field, under natural infection conditions; (ii) to determine the best time for disease assessment; (iii) to establish a method in greenhouse, based on artificial inoculation, for rapid selection of field resistant varieties. Seventeen varieties were studied in two field experiments, planted in April and July 2011; in the latter, after the harvest in May 2012, the ratoon was also evaluated. The susceptible variety SP89-1115 was used as border and planted between the blocks in two lines, dividing each experiment in two halves in order to multiply and standardize the inoculum in the area. Disease severity was evaluated every 15 days and the area under disease progress curve (AUDPC) was calculated and the maximum disease severity was obtained. To identify the best time for disease assessment, a correlation analysis between the AUDPC and each disease severity assessment was done. In greenhouse, six varieties with different reactions to the disease based on results obtained in field were inoculated with a suspension of 104 viable urediniospores mL-1 of P. kuehnii with a manual sprayer 60 days after planting. Plants were maintained in dew chamber for 24 hours and afterwards they were transferred to the greenhouse. The incubation and latent period were determined as well as the number of pustules cm-2 and disease severity. Eight out of 17 varieties evaluated in field showed high disease resistance. The varieties RB72454 and SP89-1115 were the most susceptible, followed by SP79-2233; therefore, their commercial cultivation is not recommended. The varieties RB925211, SP81-3250, RB855156 and RB92579 had intermediate reaction, with the first two showing higher disease levels. Evaluations performed in March showed the highest correlation with AUDPC, thus this period is the best for determining sugarcane reaction to orange rust. The varieties reaction in greenhouse was similar to that observed in the field, particularly in relation to susceptible and resistant cultivars. So, the method applied in greenhouse showed potential to select, in a few days, field disease-resistant varieties, besides saving space and labor and being easily implemented.

<p>As we approach the 21st Century, our society is increasingly being faced with technological advances. One of such areas of advancement is the reasearch involving human genes. The human genome-mapping project(HGMP) started on the first of october 1990 with a group of over 350 labs. but by late 90's, many important advances had been discovered concerning how to improve the human specie. With these advances came ethical questions and concerns.Both moral and legal questions have been raised as to the effectiveness and safty of this technology. It is the contention of this paper to give a clearer meaning and understanding of the ethics of genetic control.As such I will discuss the wide spread fears and anxiety brought about by the introduction of this new technology. To make this aim more comprehensible, I will pay particular attention to Joseph Fletcher and his books on Genetic control, and Humanhood: Essays In Biomedical Ethics. Fletchers ardent support for genetic control has developed worldwide debates from both ethicists and philosophers as to the safty and efficiency of genetic engineering.</p>