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Disease resistance gene pyramiding is a widely used strategy to enhance resistance durability. Marker-assisted selection (MAS) was applied to pyramide the alleles Run1 and Ren3, which confer resistance against grape powdery mildew (Erysiphe necator). Two F1 full-sibs carrying Run1 and Ren3 in heterozygosity were selfed to develop the breeding populations used in the analysis. From the 637 genotyped plants, 313 (50.6%) had the Run1 and Ren3 pyramided. Seven (1.1%) of them exhibited the two resistance alleles in homozygosity. Plants without any resistance alleles had the highest disease severity ( = 7.3), while the ones with the Run1 allele both in homozygosity and heterozygosity were highly resistant ( = 1.5). Similar level of resistance was observed in the plants containing Run1 and Ren3 pyramided ( = 1.3). Plants containing Run1 and Ren3 pyramided in homozygosity are important genetic resources for grape breeding programs in Brazil.

Plinia phitrantha and P. cauliflora are Myrtaceae species with recognized horticultural and pharmacological potential. Nevertheless, studies on molecular genetics and the evolution of these species are absent in the literature. In this study, we report the complete plastid genome sequence of these species and an analysis of structural and evolutive features of the plastid genome within the tribe Myrteae. The two plastid genomes present the conserved quadripartite structure and are similar to already reported plastid genomes of Myrteae species concerning the size, number, and order of the genes. A total of 69-70 SSR loci, 353 single nucleotide polymorphisms, and 574 indels were identified in P. phitrantha and P. caulifora. Observed evolutive features of the plastid genomes support the development of programs for the conservation and breeding of Plinia. The phylogenomic analysis based on the complete plastid genome sequence of 15 Myrteae species presented a robust phylogenetic signal and evolutive traits of the tribe. Ten hotspots of nucleotide diversity were identified, evidence of purifying selection was observed in 27 genes, and relative conservation of the plastid genomes was confirmed for Myrteae. Altogether, the outcomes of the present study provide support for planning conservation, breeding, and biotechnological programs for Plinia species.

Scale insects Stigmacoccus paranaensis (Foldi, 2006) associated with bracatinga trees (Mimosa scabrella) in Santa Catarina, Brazil, can play an important economic role and guarantee the production of “bracatinga honeydew honey”. This scale insect has the ability to excrete large amounts of honeydew, of economic importance for beekeepers, especially due to the natural occurrence of host plants at high density, known as “bracatingais”. In this sense, the objective of this study was to evaluate the honeydew produced by scale insects associated with M. scabrella in the Bom Retiro, Santa Catarina, Brazil. We determined the density of the host plant in the studied area, the intensity of infestation by scale insects, and the volume and sugar concentration of excreted honeydew. The average density of bracatinga was 437.5 individuals ha-1, and the average density of scale insects per plant was 8,287. During 10 minutes, the average rate of honeydew excretion by scale insects was 0.45 µl and 0.34 µl, respectively, in 2002 and 2004. The estimated volume of honeydew production was 0.54 L in 2002 and 0.41 L in 2004 tree-1 day-1. The highest sugar concentration was observed in 2004 (28.13%). The excretion rate was affected by climatological factors and the size of the insects. This is the first study presenting a systematic evaluation of honeydew production by scale insects in Southern Brazil. The results of the present study support production of honeydew honey in the Serra Catarinense region as an important sustainable economic and traditional activity.

Producing high-quality seeds for agroecological agriculture is needed because the plants will be exposed to a diversity of environments and management practices. Sowing times and population densities can influence the quality of seeds produced by landraces. Further, seeds for agroecological cultivation must not be contaminated by transgenes. In this context, it is necessary to know the agronomic performance of landraces outside of the recommended growing period to avoid gene flow with transgenic cultivars. Thus, the objective of this work was to determine the germination rate, vigor and sanitary quality of seeds of maize genotypes cultivated in an agroecological system at different sowing times and densities. A split-split-plot design was used in the 2016/2017 and 2017/2018 growing seasons. The physiological quality evaluation was based on germination and vigor tests, and the sanitary quality was obtained by visually examining the seeds. The results showed a significant simple effect of genotype, sowing time and density, as well as double and triple interactions among factors for all evaluated traits. The most suitable time for sowing the corn landraces evaluated in an agroecological system in western Santa Catarina is September, when the seeds exhibited the highest percentage of germination and vigor and there was a lower incidence of pathogens. At this time, a density of 55,000 plants·ha–1 had the best result for germination. Late sowing was tested to avoid gene flow from transgenic varieties that usually are sown in September, but the results indicated penalties, such as a decrease in seed yield and quality.

The objective of this work was to identify the minimum base temperature (Tb) and the maximum base temperature (TB) to predict the thermal time for six phenological stages of feijoa (Acca sellowiana) accessions. During ten noncontinuous harvests (2004 to 2017), 247 feijoa accessions, maintained in the Feijoa Active Germplasm Bank, in São Joaquim, in the state of Santa Catarina, Brazil, had their data recorded for: initial sprouting (IS), initial flowering (IF), end of flowering (EF), beginning of harvest (BH), and end of harvest (EH). Tb and TB were estimated by the Arnold’s method of least variability, and the TT requirements were obtained by Ometto’s method. Tb at 7.76°C and TB at 17.0°C were necessary when feijoa plants started growing (IS stage) just after winter; and Tb at 10.6°C and TB at 19.5°C were the calculated values from IS until BH. The budding stage of the accessions began in the mid-September (50.6%); flowering occurred predominantly in November (90%); and harvest began in March and lasted until May. About 176 days, with 1,014.4 growing degree-days, are necessary to complete the productive cycle from IS until BH. The early, intermediary, and late fruit-ripening accessions show different thermal time requirements.

The objective of this work was to use a marker-assisted selection for pyramiding the resistance loci Rpv1 and Rpv3.1 in grapevine (Vitis vinifera), and to evaluate their conferred resistance against Brazilian downy mildew (Plasmopara viticola) isolates. A progeny of 23 plants, segregating for the two resistance loci, was obtained by the cross between the Gf 2000-305-122 and Gf.Ga-52-42 genotypes. The progeny was genotyped with four microsatellite markers and phenotyped for resistance to P. viticola using a bioassay with leaf discs. Six plants containing the Rpv1 and Rpv3.1 pyramided loci were identified by the molecular analysis. Plants harboring the Rpv1 + Rpv3.1, Rpv3.1, and Rpv1 loci showed 12.8, 30.0, and 33.1 sporangiophores per leaf disc, respectively. Plants with no resistance loci showed a dense sporulation. The phenotypic analysis of the expression of the two pyramided loci was only confirmed for four plants that showed the highest resistance level, i.e., mean value of 1.8 sporangiophores. A high-throughput method for pyramiding the Rpv1 and Rpv3.1 loci was developed, which confirmed the increased resistance to P. viticola. The selected elite genetic material shows a high resistance to downy mildew and elevated enological potential for grapevine breeding in Brazil. Resumo: O objetivo deste trabalho foi o emprego da seleção assistida por marcadores moleculares para piramidação dos locos de resistência Rpv1 e Rpv3.1, em videira (Vitis vinifera), e avaliar o nível de resistência conferido por eles contra isolados brasileiros de míldio (Plasmopara viticola). Uma progênie de 23 plantas, com segregação para os dois locos de resistência, foi obtida do cruzamento entre os genótipos Gf2000-305-122 e Gf.Ga-52-42. A progênie foi genotipada com quatro marcadores microssatélites e fenotipada, quanto à resistência a P. viticola, em discos foliares. A análise molecular identificou seis plantas com os locos Rpv1 e Rpv3.1 piramidados. Plantas com os locos Rpv1 + Rpv3.1, Rpv3.1 e Rpv1 apresentaram 12,8, 30,0 e 33,1 esporangióforos por disco foliar, respectivamente. As plantas sem locos de resistência tiveram esporulação densa. A análise fenotípica da expressão dos dois locos piramidados foi confirmada somente para quatro plantas que mostraram o maior nível de resistência, isto é, média de 1,8 esporangióforos. Desenvolveu-se uma metodologia de alto rendimento para a piramidação dos locos Rpv1 e Rpv3.1, que confirmou o aumento da resistência a P. viticola. O material genético superior selecionado apresenta alta resistência ao míldio e elevado potencial enológico para o melhoramento da videira no Brasil.

Downy mildew (Plasmopara viticola) is the main grapevine disease in humid regions. In the present investigation, marker-assisted selection (MAS) was used to develop grapevine lines homozygous in loci Rpv1 and Rpv3 for resistance against P. viticola. The experimental populations UFSC-2013-1 (n = 420) and UFSC-2013-2 (n = 237) were obtained by self-pollination of two 𝐅 𝟏 full-sib plants, originated from a cross between two distinct breeding lines containing the downy mildew resistance loci Rpv1 and Rpv3 in heterozygosity. The two experimental populations were genotyped with four microsatellite markers flanking the two downy mildew resistance loci. Among 637 genotyped plants, 300 (48.2%) were homozygous for at least one resistance locus and 10 (1.57%) were homozygous for both Rpv1 and Rpv3 alleles. These 10 plants challenged with P. viticola inoculum showed a clearly enhanced level of resistance. These plants have a great potential as resistance donors in grapevine breeding.

Among the cultivation problems of apple production in Brazil, Apple Leaf Spot (ALS) disease represents one of the main breeding challenges. This study aims at analyzing the genetic diversity among 152 apple scion accessions available at the Apple Gene Bank of EPAGRI, located in Caçador, Santa Catarina/Brazil. Eleven genomic SSR loci were analyzed to assess genetic diversity of ALS resistant and susceptible accessions. Results revealed high genetic diversity of the studied accessions, being 120 exclusive alleles (67 unique) from scion accessions resistant to ALS, and a mean PIC of 0.823. The locus Probability of Identity (I) ranged from 0.017 to 0.089. The combined I was 4.11 x 10-16, and the Power of Exclusion was 99.99999259%. In addition, the DNA fingerprint patterns will contribute as additional descriptors to select parental for crosses and early identification of apple accessions for breeding purposes, and also for cultivar protection.

Woolly apple aphid (WAA; Eriosoma lanigerum Hausm.) is a major insect pest that has significant economic impact on apple growers worldwide. Modern breeding technologies rely on several molecular tools to help breeders select genetic determinants for traits of interest. Consequently, there is a need for specific markers linked to the genes of interest. Apple scions and rootstocks have an additional barrier to the introduction of pest resistance genes due to the presence of self-incompatibility S-RNase alleles. The genetic characterization and early identification of these alleles can amplify the contribution of a breeding program to the selection of resistant genitors that are as compatible as possible. In this study, we identified the Er1 gene involved in the resistance to WAA in Malus prunifolia var. ringo, also known as ‘Maruba Kaido’ rootstock, and we analyzed the inheritance pattern of the WAA resistance Er1 gene in a segregant population derived from Malus pumila ‘M.9’ and ‘Maruba Kaido’ rootstocks. The self-incompatibility of S-RNase alleles S6S26 of ‘Maruba Kaido’ were also identified along with their inheritance pattern. We also confirmed the identification of the S1S3 alleles in the ‘M.9’ rootstock. To the best of our knowledge, this is the first study to characterize WAA resistance and RNase S-alleles in ‘Maruba Kaido’. Furthermore, we discuss the potential use of the genetic markers for these genes and their potential impact on apple breeding programs.

Em Santa Catarina, foi observado aumento da cobertura florestal nas últimas décadas, o que vem construindo uma paisagem florestal retalhada por um grande mosaico de fragmentos de vários estádios sucessionais. Neste trabalho, buscou-se avaliar o dinamismo do processo sucessional de dois diferentes estádios sucessionais. Em área florestal de 40 ha localizada no Município de São Pedro de Alcântara, SC, abandonada pelo uso agropecuário em meados de 1970, foram estabelecidas aleatoriamente parcelas permanentes (50 x 50 m), duas em estádio florestal secundário médio (SM) e quatro em estádio secundário avançado (SA). As avaliações anuais durante o período de 1994 a 2000 de todas as plantas arbóreas com DAP >5 cm revelaram que no SM os valores da densidade de plantas, residentes, recrutadas, mortas e ramificadas foram superiores em relação aos no SA. No entanto, a riqueza de espécies, área basal e distribuição diamétrica foram superiores no SA. Botanicamente, foram observadas com muita clareza as espécies e as famílias dominantes de cada estádio e igualmente o dinamismo sucessional desse grupo de espécies, aumento explosivo e posterior declínio e substituição, evidenciando-se perfeitamente a funcionalidade dos grupos ecológicos nessa tipologia florestal. Por fim, destacou-se que a densidade de plantas ramificadas é notadamente superior em estádios florestais secundários iniciais, embora as taxas de incremento corrente anual fossem similares. As avaliações florísticas mostraram, ainda, que as florestas no litoral catarinense se encontravam em dinâmica sucessional, em que espécies climáxicas vêm substituindo paulatinamente o grupo de espécies pioneiras, elevando a diversidade de espécies e a biomassa florestal.

O objetivo deste trabalho foi avaliar o número de anteras por flor, grãos de pólen por antera e capacidade germinativa do pólen de diferentes cultivares de macieiras. O trabalho foi executado no Laboratório de Fisiologia do Desenvolvimento e Genética Vegetal da Universidade Federal de Santa Catarina, e as coletas a campo foram realizadas na Epagri/Estação Experimental de Caçador-SC, em outubro de 2005. Foram utilizadas as seguintes cultivares comerciais de macieira desenvolvidas no Brasil: Primícia, Princesa, Fred Hough, Catarina, Baronesa, Lisgala, Suprema, Condessa, Daiane, Duquesa, Imperatriz e Joaquina. As cultivares de macieira Condessa, Princesa, Eva, Duquesa, Imperatriz, Gala, Fred Hough, Daiane, Baronesa e Suprema produzem pólen em quantidade suficiente e com boa capacidade germinativa. A cv. Condessa, embora apresente alta capacidade germinativa de pólen, produz menos anteras e grãos de pólen por antera que as demais. A cv. Princesa é a que apresenta o melhor perfil como polinizadora, por conjugar número de anteras/flor, número de grãos de pólen/antera e capacidade germinativa do pólen mais satisfatórios. The objective of this study was to evaluate the number of anthers per flower, the number of pollen grains per anther and the pollen germination capacity of different cultivars of apple trees. The study was performed at the Physiology and Plant Genetics Laboratory of Federal University of Santa Catarina. The field collecting were performed at Epagri / Caçador Experimental Station, in Santa Catarina State during October, 2005. It was used the following apple cultivars developed in Brazil: Primícia, Princesa, Fred Hough, Catarina, Baronesa, Lisgala, Suprema, Condessa, Daiane, Duquesa, Imperatriz and Joaquina. It was concluded that the apple cultivars Condessa, Princesa, Eva, Duquesa, Imperatriz, Gala, Fred Hough, Daiane, Baronesa and Suprema produce pollen grains of satisfactory quantity and of good germination capacity. The cv. Condessa, although having high pollen germination capacity, produces less anthers and less pollen grains per anther than the others. Princesa is the cultivar of best pattern as pollinizer, once it combines number of anthers/flower, number of pollen grains/anther and pollen germination capacity in a better satisfactory level.

O objetivo deste trabalho foi avaliar o desenvolvimento do tubo polínico em cruzamentos entre cultivares brasileiras de macieira. Realizou-se a polinização dirigida entre cultivares com mesma época de floração (34 cruzamentos). As polinizações foram realizadas em três estigmas de cada uma das dez flores emasculadas por cruzamento. O crescimento dos tubos polínicos foi avaliado por meio da técnica da fluorescência, em flores coletadas 120 horas após a polinização. Na grande maioria das polinizações cruzadas, houve alta percentagem de tubos polínicos que cresceram até o ovário. O acompanhamento do crescimento do tubo polínico pela técnica de fluorescência permite separar cruzamentos compatíveis ou parcialmente compatíveis dos incompatíveis. The objective of this study was to evaluate pollen tube growth in crosses between Brazilian apple cultivars. Artificial pollination was carried out among cultivars that bloom at the same time (34 crosses). Pollination was done on three stigmas in each of the ten emasculated flowers per crossing. Fluorescence was used to visualize pollen tube growth in flowers collected 120 hours after pollination. In most of the cross-pollinations, high percentage of pollen tubes reached the ovary. The visualization of pollen tube growth by the fluorescence technique permitted the separation of compatible or partial compatible crosses from the incompatible ones.

Identifica e analisa criticamente a produção científica brasileira, no campo da saúde pública, sobre os organismos geneticamente modificados, no que concerne à (in)segurança alimentar. Para tanto, realizou-se uma revisão bibliográfica nos portais do Scientific Eletronic Library Online (SciELO) e da Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (Capes). Dos 716 trabalhos encontrados, apenas oito abordam a segurança alimentar dos transgênicos, através, principalmente, da exposição aos riscos e das incertezas desses produtos para a saúde e o meio ambiente. A principal conclusão do estudo refere-se ao fato de que os oito trabalhos analisados discursam, não sobre a segurança, mas sobre a insegurança dos alimentos geneticamente modificados. Based on a bibliographic review, the article identifies and offers a critical analysis of scientific production by the public health field in Brazil on genetically modified organisms and food (in)security. Of the 716 articles found on the portals of the Scientific Electronic Library Online (SciELO) and the Coordinating Agency for the Development of Higher Education (Capes), only 8 address the food security of transgenic products, primarily in terms of risk exposure and the uncertainties about how these products impact health and the environment. The main conclusion involves the fact that the eight analyzed articles do not speak to the question of the security but rather the insecurity of genetically modified foods.

O objetivo deste trabalho foi avaliar os componentes da variância fenotípica para o caráter rendimento de grãos a fim de gerar informações que auxiliem o melhoramento de plantas e verificar a sensibilidade genotípica entre genótipos de feijão do grupo preto. Para tanto, foi avaliado o caráter rendimento de grãos de 12 genótipos de feijão em 10 ambientes do Estado de Santa Catarina, por meio do método REML/BLUP. A decomposição dos componentes da variância fenotípica permitiu ampliar as inferências sobre os resultados obtidos para o caráter rendimento de grãos além daquelas tradicionalmente utilizadas na avaliação de linhagens. O genótipo BRS Campeiro foi o que apresentou maior média de rendimento de grãos e ainda o que obteve o maior valor predito, podendo ser indicado para todos ambientes avaliados. Nos ambientes 1 (2004/Canoinhas), 2 (2005/Canoinhas), 9 (2004/Ponte Serrada) e 10 (2005/Ponte Serrada), o valor de rendimento de grãos, em todos os genótipos avaliados, foi acima da média geral. Os genótipos CHP 9858, CHP 9859, CHP 9954 e CHP 9965 revelaram uma adaptabilidade específica ao ambiente 6 (2005/Ituporanga). This study aimed to evaluate the phenotypic variance components for grain yield characters on the sense to be useful for breeding programs, and verify the genetic sensibilility among genotypes of black beans group. The grain yield character was evaluated in twelve black beans genotypes in ten environments of the Santa Catarina Estate through the REML / BLUP method. With the phenotypic variance components decomposition it was possible to provide additional information than traidicionally utilized in line evaluations for grain yield character. The highest grain yield average and the highest predicted value was obtain at genotype BRS Campeiro, which may be suitable for all evaluated environments. In the environments 1 (2004/Canoinhas), 2 (2005/Canoinhas), 9 (2004/Ponte Serrada) e 10 (2005/Ponte Serrada) higher grain yield has been obtained above general mean in all evaluated genotypes. The genotypes CHP 9858, CHP 9859, CHP 9954 and CHP 9965 presented specific adaptability to environment 6 (2005/Ituporanga).

Among all of the temperate fruit trees, the apple tree is the one that has attracted more attention when it comes to obtaining rootstocks with characteristics of good adaptation, resistance or sanity. The development of an efficient method to characterize genotypes with tolerance to the aluminum is the first step for the accomplishment of genetic mechanisms studies involved in the inheritance of this character. Thus, the present work aimed to evaluate the tolerance to aluminum of the apple tree rootstocks M.9 and Marubakaido in five concentrations (0, 50, 150, 250 and 350 µM L-1) in nutritious solution. The cuttings of Marubakaido, in the intermediate concentration of aluminum presented smaller root and aerial growth. M.9 showed smaller root growth in the concentrations of 250 and 350 µM of aluminum. The evaluated growth characteristics permitted to identify the apple rootstock Marubakaido as more tolerant than the M.9, and the concentration of 350 µM L-1 is the most efficient to identify the tolerance to aluminum in the 15 days of cultivation in nutritious solution. It is expected that later, this data can be used in works of individuals' selection in segregated populations accomplished in crossings with these two apple rootstocks.

O maracujazeiro-doce, Passiflora alata Curtis, é uma planta frutífera que vem despertando interesse econômico principalmente para o consumo in natura. Contudo, precisam ser superados alguns entraves tecnológicos em relação ao seu cultivo, tais como a ausência de cultivares que apresentem frutos com alto rendimento de polpa, resistência mecânica e elevado teor de sólidos solúveis totais. Nesse sentido, este trabalho teve por objetivo estimar a herdabilidade (h²) e o ganho genético esperado com a seleção, para os caracteres peso do fruto, peso da polpa, espessura da casca, sólidos solúveis totais e rendimento de polpa em maracujazeiro-doce, por meio da avaliação de 36 cruzamentos envolvendo seis genitores femininos e seis masculinos. Os resultados obtidos evidenciaram uma ampla variação na magnitude dos valores da h² entre os cruzamentos e a predominância de efeitos gênicos de aditividade no controle genético dos caracteres. Assim, é necessário levar em consideração o grande efeito do fator cruzamento na estimativa da h², bem como a realização da seleção direta na maioria das progênies avaliadas em razão de que os efeitos aditivos predominaram no controle da maioria dos caracteres estudados.

The objetive of this work was to rescue immature embryos of apple rootstocks Malus prunifolia (Marubakaido) and Malus pumila (M9) after 40-60 days of pollination and to put them into MS culture media supplemented with agar (6 g L-1) and casein hydrolysate (500 mg L-1). Embryos originated from interspecific crosses and open pollination showed differences in the in vitro responses, depending on the female parent, the developmental stage of the embryo, and the culture medium composition. Embryos of the M. pumila rootstock, rescued within 40 days after pollination and put in culture medium supplemented with indolacetic acid (IAA), gibberellic acid (GA3), kinetin and maltose, resulted in a normal development of plantlets. However, embryos originating from hand-pollination, cultivated in medium supplemented with 14 µM IAA, 5 µM kinetin and 1.5 µM Ga3 (MS1), mainly those of M. prunifolia x M. pumila, showed a high percentage of rusted embryos (96.2%). Embryos from open pollination of M. prunifolia and M. pumila formed calluses. It was possible to identify the influence of the female parent by the enhanced development of M. pumila shoots derived from open or hand-pollination. The crossing of responsive species and the use of the technique of embryo culture provided a rapid and uniform germination and, consequently, the development of fully normal seedlings.

No presente trabalho, estudaram-se características associadas à germinação in vitro e ao desenvolvimento in vivo do tubo polínico em seis variedades-copa e de porta-enxertos de macieira como subsídios para o estabelecimento de programas de melhoramento genético. Utilizou-se de pólen de seis cultivares de macieira inoculado em meio de cultura com ágar (10 g.L-1) em água destilada, combinados com concentrações de sacarose (0; 10; 20; 30; 40 e 50%) e ácido bórico (0 e 40 mg.L-1). Para o estudo do desenvolvimento do tubo polínico, realizou-se coleta das flores em quatro períodos (6; 12; 24 e 48 horas após as polinizações) em M9 x Marubakaido e a autofecundação em M9, sendo os tubos polínicos analisados em coloração de azul de anilina acidificada/carmim acético e em fluorescência. A sacarose, em concentrações entre 15% a 25%, pode ser empregada com sucesso para a germinação in vitro de grãos de pólen da macieira. O ácido bórico não teve efeito positivo para esta característica. Na ausência do ácido bórico e na presença de 15% de sacarose, observaram-se os maiores percentuais de germinação: Fuji (51,1%), Imperatriz (31,7%), M.9 (20,8%), Catarina (19,2%), Gala (13,7%) e Marubakaido (6,1%). Quanto ao desenvolvimento do tubo polínico, com 12 horas da polinização, iniciou-se a germinação no pólen, no estigma, no cruzamento M.9 x Marubakaido, e após 24 horas da polinização observou-se 83% de germinação. As técnicas de coloração com azul de anilina acidificada com carmim acético e de visualização em fluorescência foram eficientes na visualização e coloração dos grãos de pólen e do desenvolvimento dos tubos polínicos. In the present work it was studied features associated to the germination of pollen and the development of pollen tubes in six apple varieties as subsidies for the establishment of genetic improvement programs. Pollen grains were inoculated in culture medium with distilled water, agar (10 g. L-1), combined with sucrose at 0, 10, 20, 30, 40 and 50% and boric acid at 0 and 40 mg. L-1. For the study of pollen tubes development flowers were collected at 6, 12, 24 and 48 hours after antesis in M.9 x Marubakaido and in the self-pollinated M.9, being the pollen tubes analyzed in staining with blue aniline with acetic carmim and in fluorescence. Sucrose in concentrations ranging from 15% to 25% can successfully be used for the in vitro germination of pollen grains. Boric acid was not effective in promoting in vitro germination of pollen grains. In the absence of boric acid and in the presence of 15% of sucrose it was observed the largest germination rates: Fuji (51.1%), Imperatriz (31.7%), M.9 (20.8%), Catarina (19.2%), Gala (13.7%), and Marubakaido (6.1%). In the crossing M.9 x Marubakaido after 12 hours of pollination the pollen germination began in the stigma and after 24hrs it was observed 83% of germination. The techniques employed were efficient in the visualization and coloration of the pollen grains and of development of tube pollen.

A dormência em sementes de macieira é um dos fatores limitantes para o avanço nos programas de melhoramento genético nesta espécie. Assim, o presente estudo objetivou estudar a germinação in vitro de embriões dormentes do porta-enxerto de macieira M9, oriundos da EE São Joaquim da EPAGRI/SC. Os embriões foram excisados de sementes maduras e inoculados em meio basal MS, adicionado de sacarose (30 g.L-1), ágar (6 g.L-1), água de coco (15%), caseína hidrolisada (CH) (500 mg.L-1), AIA (0 e 14 µM); AG3 (0 e 1,5 µM), Kin (5 µM), 2-iP (12 µM); BAP (4 µM). As culturas foram mantidas no escuro por 10 dias e transferidas para sala de crescimento sob regime de luz de 16 horas, temperatura de 25 ± 2°C e 40 µmol de radiação luminosa. A maior percentagem de germinação (75%) foi obtida em meio MS suplementado com CH (500 mg.L-1), AIA (14 µM), AG3 (1,5 µM) e Kin (5 µM). Quando a Kin foi substituída por BAP (4µM), observou-se a formação de calo, sobre o qual se originaram gemas e brotações, cujos valores médios foram de 2,3 brotos por embrião e 12,3 gemas por brotação. Em relação ao comprimento das brotações, não houve diferença significativa entre os tratamentos. A maior percentagem de indução de calos ocorreu em meio de cultura suplementado com AIA, Kin e 2-iP. O meio de cultura MS/2 suplementado com CH e água de coco e isento de fitorreguladores, resultou em 25% de germinação. Já, o número de raízes foi maior no meio de cultura MS suplementado com AIA (14 µM), AG3 (1,5 µM) e CH. O comprimento médio das raízes (4,0 cm) não foi afetado por nenhum tratamento em particular. Desta forma, esta técnica é uma alternativa eficiente ao uso de tratamentos de frio para a superação da dormência. The embryo dormancy in apple is a limiting factor in breeding programs with this species. Thus the present work was carried out in order to study the in vitro germination of M9 apple dormant embryos, originated from the Experimental Station of São Joaquim (EPAGRI/SC). The embryos, excised from mature seeds were inoculated in the basal culture medium MS supplemented with of sucrose (30 g.L-1), coconut water (15%), casein hydrolysate (CH) (500 mg.L-1), AIA (0 and 14 µM); GA3 (0 and 1.5 µM); and three citokinins sources: (Kin (5 µM); 2iP (12 µM) and BAP (4 µM). The culture medium was gellified with agar (6 g.L-1). The cultures were maintained in the dark during 10 days, then transferred to growth room under 16 hours of light period, 25 ± 2°C, temperature, and 19 µE.m-2.s-1 of luminous radiation. The results showed that the highest value for embryo germination (75%) was obtained in MS culture medium supplemented with CH, AIA (14 µM), GA3 (1.5 µM), and Kin (5 µM). When, in this treatment the Kin was replaced by BAP (4 µM), it was observed the callus induction and the subsequent proliferation of buds and shoots, reaching values of 2.3 shoots/embryos and 12.3 buds/shoot. The length of shoots was 4 cm, without statistical differences between the different treatments. The highest percentage of callus induction occurred in culture medium supplemented with AIA, Kin, and 2-iP. The culture medium MS half strength supplemented with CH, coconut water and free of growth regulators resulted in values of 25% of germination. The root number was highest in the culture medium supplemented with AIA (14 µM), GA3 (1.5 µM), and CH. The average root length (4.0) was not affected by any particular treatment. Thus, this technique is an efficient alternative to the cool treatments for dormancy suppression.

A cultura in vitro de embriões permite desenvolver estudos nas áreas de fisiologia e melhoramento, possibilitando o resgate de embriões imaturos, oriundos de cruzamentos que podem ser incompatíveis. Em macieira, geralmente, os embriões imaturos apresentam dormência e baixa germinação. O objetivo deste trabalho foi testar concentrações de BAP (6-benzilaminopurina) em diferentes períodos de imersão para superação da dormência e germinação de embriões imaturos de macieira. Os embriões foram extraídos de sementes retiradas de frutos oriundos do cruzamento entre os porta-enxertos de macieira Marubakaido (Malus prunifolia) x M9 (Malus pumilla), realizado em plantas matrizes cultivadas na Epagri -- São Joaquim (SC). Os 50 frutos colhidos ao acaso foram submetidos a uma esterilização com etanol 96º por 10 min e após com solução de hipoclorito de sódio a 2% por 20 min. As sementes foram submetidas a uma desinfestação, utilizando-se etanol 70% por 30 s e solução de hipoclorito de sódio 1,25% por 15 min, seguindo-se três lavagens com água esterilizada e autoclavada. Os embriões foram inoculados em 10 ml de meio MS/2, suplementado com 100 mg.L-1 de mio-inositol, 30 g.L-1 de sacarose e com BAP (0, 6 e 12 mg.L-1) e 6 g.L-1 de agar, com pH ajustado para 5,8. Os embriões foram mantidos por 24 ou 48 horas neste meio e depois transferidos para um meio MS/2 sem regulador vegetal. Não ocorreu contaminação nem oxidação em nenhum embrião. A concentração de BAP que promoveu maior crescimento dos embriões foi de 6 mg.L-1, mas o melhor aspecto quanto à intensidade de coloração e formação de brotos foi obtido utilizando-se 12 mg.L-1. The embryos culture in vitro allows studies in the physiology breeding areas, facilitating the rescue of immature embryos, originated from incompatible crossings. In apple, the immature embryos generally present dormancy and lower germination. The objective of this work was to test concentrations of BAP in different immersion periods for break of the dormancy and germination of apple immature embryos. The embryos were extracted from fruits seeds originated from the crossing between apple rootstock Marubakaido and M.9, accomplished in adult plants in Epagri - São Joaquim (SC). The 50 collected fruits were submitted to a sterilization with alcohol 96º for 10 minutes and after with NaClO solution (2%) for 20 minutes. The removed seeds were submitted to a disinfestations treatment with alcohol 70% for 30 seconds and with NaClO solution (1,25%) for 15 minutes, followed by three washes with sterilized water and autoclaved. The embryos were inoculated in 10 ml of MS/2 culture medium, to which was added 100 mg.L-1 of myo-inositol, 30 g.L-1 of sucrose and with BAP (0, 6 and 12 mg.L-1) and 6 g.L-1 of agar and with pH adjusted to 5.8. The embryos were maintained by 24 or 48 hours in this medium and later transferred for a medium MS/2 without growth regulators. There was no contamination or oxidation. The concentration that promoted larger growth of the embryos was of 6 mg.L-1. However, the best general aspect in the coloration intensity and formation of sprouts was obtained when medium containing 12 mg.L-1 was utilized.

A discussão mundial sobre os riscos e impactos dos OGMs na saúde humana e animal e ao meio ambiente, bem como seus impactos socioeconômicos, estão longe de terminar, pois pouca informação científica foi gerada. Parte dessa informação suporta hipóteses de riscos previamente levantadas. Assim, em vários casos, já foi constatada a presença de genes de plantas transgênicas em outras plantas e em outros organismos. Portanto, a disseminação de genes tanto para plantas da mesma espécie como para espécies bem diferentes já pode ser considerado um risco real. O princípio da equivalência substancial está permitindo que as plantas transgênicas sejam liberadas para o cultivo comercial com testes de curta duração e em quantidade e qualidade insuficientes para que os alimentos derivados das mesmas sejam considerados sadios e seguros. Dessa forma, o uso do princípio da precaução se constituiu na medida mais adequada para este momento, até que os dados científicos indiquem os reais impactos destas plantas na saúde humana, animal e no meio ambiente. The potential risks of GMOs, their impact on human and animal health, and on the environment, as well as their socioeconomic effects, have generated a worldwide discussion which is far from drawing to a close for lack of sufficient scientific information. Part of this information supports risk-hypotheses previously put forward. Thus the presence of transgenic plant genes in other plants and in other organisms has been confirmed in several occasions. Therefore, gene dissemination to plants of the same species as well as to widely different species is already regarded as an actual risk. The principle of substantial equivalence has opened the way for the liberation of transgenic plants for commercial crops, despite short-term tests, which are quantitatively and qualitatively insufficient to certify that the foods deriving from those plants are healthy and safe. Thus, the adoption of the so-called precautionary principle (PP) has turned out to be the most adequate safety measure to date, or else until scientific data should be able to demonstrate the actual impact of transgenic plants on human and animal health, and on the environment.

Visando ao desenvolvimento de um novo protocolo para a micropropagação da goiabeira serrana (Acca sellowiana (Berg) Burret) foram estabelecidos experimentos com segmentos nodais e microestacas. As citocininas 6-Benzilaminopurina (BAP), Cinetina (Kin) e 2-Isopenteniladenina (2-iP) foram adicionadas ao meio de cultura Woody Plant Midium-WPM, visando à proliferação de brotações múltiplas dos genótipos 53B-7, 101, 529 e 152-12 x 458. As microestacas obtidas in vitro foram submetidas a diferentes períodos de indução, em 20 miM de ácido indolbutírico (AIB) e, posteriormente, transferidas para meio de cultura isento desse fitorregulador para a indução de raízes ou, alternativamente, submetidas a diferentes concentrações e tempos de exposição em AIB e transferidas para substrato. As citocininas empregadas não promoveram aumento na taxa de proliferação de brotos em relação à testemunha. O meio de cultura basal WPM, adicionado de Kin (5 miM), proporcionou maior altura média dos brotos. Segmentos nodais do acesso 101 cultivados em meio de cultura WPM, isento de fitorreguladores, apresentaram maiores taxas médias de proliferação. Pulsos de seis dias com AIB (20 miM) induziram uma maior taxa de enraizamento (68,9%), um maior número médio de raízes (1,3 raízes) e raízes com maior comprimento médio (5,6miM). Microestacas enraizadas ex vitro, pela imersão em AIB (100 miM) por 60 minutos, resultaram em maior altura das plantas (45,3mm), número de raízes secundárias (11,3 raízes), massa fresca (1069mg) e seca das raízes (282mg). The objective of this study was to establish a micropropagation protocol for Acca sellowiana (Berg) Burret. Nodal segments of in vitro cultivated plantlets of the genotypes 53B-7, 101, 529 and 152-12 x 458 were inoculated in test tubes containing 15ml of Woody Plant Medium-WPM solid medium supplemented with the cytokinins BAP, Kin, and 2-iP. For rooting purpose the microcuttings were submitted to different inductive periods of time with indolilbutiric acid-IBA (20 muM), then transferred to a basal solid medium free of growth regulators, or alternatively to ex vitro substrate in a phytotron. The three cytokinins did not improve the multiple shoot regeneration rates when compared with the control. The highest shoot height was observed in the WPM medium supplemented with Kin (5 muM). Nodal segments of the genotype 101, cultivated in WPM medium free of growth regulators showed higher regeneration rates than the other treatments. Six days pulses of IBA (20 muM) induced 68.9%, of microcutting rooting as well the highest values for root (5.6mm) and length number (1.3 roots). ex vitro rooting treatment of micropropagated microcuttings with IBA (100 muM) for 60min resulted in the highest values for plantlet height (45.3mm), secondary root number (11.3 roots), fresh (1069mg) and dry weight (282mg).of roots.