The cultivation of passion fruit occupies an important place in Brazilian fruit culture; however, there have been successive declines in production. The main cause of this retraction in production is an increase in the incidence of Cowpea aphid-borne mosaic virus. This virus can cause severe deformation of the fruit and make passion fruit production inviable. Due to a lack of cultivars resistant to this virus, the Universidade Estadual do Norte Fluminense Darcy Ribeiro passion fruit breeding program has sought to develop resistant cultivars. The objective of this work was to evaluate the resistance to CABMV of a passion fruit second generation backcross (BC 2 ) segregating population via the REML/BLUP procedure aiming at selecting resistant genotypes with agronomic characteristics to start a recurrent selection program and possibly produce a new passion fruit cultivar. Virus resistance was measured by the average area under the disease progress curve using a score scale, evaluating the percentage of symptoms in the plant and young leaves. The total fruit mass produced per plant was used to assess fruit production. Based on this information, the components of variance and genetic value were estimated via REML/BLUP. The highest values estimated for genetic parameters, for the two characteristics evaluated, were ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 20 (1): gmr18687 R.F. Vidal et al. 2based on the average of each family. The BC 2 -17 family showed the best additive genetic gain concerning resistance to CABMV and the worst for fruit production. The BC 2 -293 family, had the highest estimated value of genetic gain for fruit production. The genetic variability found in the BC 2 segregating population allows us to select superior genotypes. Twenty-nine genotypes were selected to start the recurrent selection program aimed at resistance to CABMV. The -Two genotypes (BC 2 -89 and BC 2 -323) showed potential to be launched as CABMV resistant passion fruit cultivars.

Torres 2 -UEMASUL Alex Guimarães Sanches 3 -UNESP RESUMO O bacurizeiro é uma espécie frutífera e madeireira, está distribuída por toda a Região Amazônica, de alto valor extrativistas, sendo raros os pomares para exploração da polpa com essa espécie. Diante disso o trabalho objetivou avaliar a influência de bioestimulantes no pré-tratamento de sementes de bacurizeiro e a eficácia desses ao longo da etapa de armazenamento. Para o experimento foram utilizadas 3500 sementes, as quais foram revestidas com uma solução pastosa (talco+ álcool) com os seguintes bioestimulantes: cinetina, ácido giberélico, ácido indolbutírico e ácido indolacético ambos na concentração de 50 mg L-1, além das sementes que não foram envolvidas representando o tratamento testemunha. A germinação das sementes foi influenciada pelos tratamentos de frio e condutividade elétrica demostrando ser sensível a baixas temperaturas e apresentar melhores condições de germinação com alto teor de água nas sementes armazenadas.

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Crossing and developing inbred lines have been promising options for guava breeding programs. The purpose of this study was to evaluate the genetic divergence among genotypes of S1 inbred guava families by means of the Gower’s technique and the Ward-MLM methodology, to verify the correlation and relative contribution of traits, as well as to identify descriptors with minimum efficiency for this species. The experiment was implemented at the Estação Experimental da Ilha Barra do Pomba, in the municipality of Itaocara, RJ, Brazil. A randomized block design with 18 inbred families, three replicates, and ten plants per plot was used for the experimental design. After 19 months from the planting of the experiment, the 61 earliest and most productive genotypes (individual plants) were evaluated. For this purpose, 29 descriptors were evaluated, of which fifteen were qualitative and fourteen, quantitative. The characteristics required to obtain the distance matrix were analyzed based on the Gower algorithm, and a comparative cluster between the dendrograms of the morphoagronomic variables was achieved from this matrix. Lastly, the Ward-MLM procedure was applied to form the clusters of inbred families. By using all 29 descriptors, greater efficiency was achieved in cluster discrimination. Hence, according to the results identified, it is not possible to indicate minimum descriptors for the culture. Using the Ward-MLM method, the descriptors that most contributed to the divergence among the genotypes were fruit flesh mass, fruit weight, fruit diameter, fruit flesh thickness, fruit placental mass, and fruit length. The most divergent genotypes can be recommended for further crosses or self-pollinations to develop new lines in the guava breeding program of UENF.