Abstract The present study was performed for the morphological and cytogenetic description of F1 hybrids obtained from a cross between Passiflora coccinea Aubl. and Passiflora hatschbachii Cervi. Hybridization was confirmed by genomic in situ hybridization (GISH). Corona banding was the most relevant floral descriptor for separating the hybrids into two groups, the cultivars P. 'Vivis' and P. 'Jhovi', and the parents and hybrids had diploid chromosome number 2n = 18. The F1 progenies exhibited normal meiotic behavior with normal tetrad production, which guaranteed high pollen viability (>70%) and fertile hybrids. Therefore, P. 'Vivis' and P. 'Jhovi' have the potential to be used for ornamental plants market.

RESUMO. Tendo em vista a importância do cultivo do maracujazeiro, é de grande relevância o aprimoramento dos trabalhos de melhoramento genético a fim de possibilitar com maior rapidez o desenvolvimento de novas cultivares. O objetivo do presente trabalho foi comparar quatro índices de seleção e o método REML/BLUP na avaliação de ganhos genéticos preditos das características de interesse. Foram avaliadas 81 progênies de irmãos-completos, oriundas do terceiro ciclo de seleção recorrente, em uma safra, em um ambiente. O delineamento experimental utilizado foi o de blocos ao acaso com parcelas constituídas por cinco plantas. As características avaliadas foram: número de frutos, produção total, massa do fruto, diâmetro longitudinal do fruto, diâmetro transversal do fruto, porcentagem de polpa do fruto, espessura da casca e teor de sólidos solúveis totais. O índice de seleção de Mulamba & Mock proporcionou os melhores resultados para a seleção das progênies. O método REML/BLUP mostrou-se mais eficiente, tendo selecionado progênies com ganhos genéticos preditos melhores que os dos índices de seleção testados.

ABSTRACT. Breeding programmes must be improved to accelerate the development of new cultivars due to the commercial importance of passion fruit. This study compared four selection indexes and the REML/BLUP methodology in an assessment of predicted genetic gains in the traits of interest. A total of 81 full-sib progenies derived from the third cycle of recurrent selection were assessed for one harvest in one environment. The experiment was arranged in a randomized complete block design with five plants per plot. The following traits were assessed: number of fruits, total yield, fruit mass, fruit longitudinal diameter, fruit transverse diameter, fruit pulp percentage, shell thickness and content of soluble solids. The Mulamba & Mock index produced the best results for the selection of progenies. The REML/BLUP method was the most efficient and selected progenies with predicted genetic gains better than the selection indexes tested.

Abstract Guava plays an important role in Brazilian agribusiness. Among other goals, guava breeding programs aim to achieve more productive cultivars and improved fruit quality. Thus, the present study aimed to investigate genetic variability in full-sib progenies of Psidium guajava (guava) and estimate the genetic progress obtained from different selection criteria in order to select the most promising genotypes. This is the first work that uses these criteria of selection to guava. The experiment was conducted in randomized block design with 2 replicates, and 10 progenies were assessed, with 12 plants per plot. Direct and indirect selection and the classic index with 2 economic weights were used for predicting the genetic gain between and within progenies. The 5 best progenies among those analyzed and 4 plants within the progenies were selected. Direct selection provided higher gains for number of fruits, and indirect selection generated small gains for the other traits. When the trial values were used as economic weight, the classic index was the selection criterion that showed the best results for gains in fruit number and fruit weight, being indicated as the most appropriate selection strategy for genetic breeding in the studied population.

The genus Passiflora encompasses many species that are endemic to the Brazilian territory, including some with economic value. Studies on genetic diversity in this genus are fundamental because they allow understanding genetic variability and distance. The present study aimed to determine the genetic variability and distances among 10 species of the genus Passiflora by using microsatellite markers (Simple Sequence Repeat, SSR). Twenty-eight heterologous microsatellite markers were tested, but only 12 were used in the diversity analysis because they amplified in at least 80% of the species. A clear separation was observed among the subgenuses studied, as well as wide variation among the accessions of Passiflora. This knowledge enables breeders to explore diversity and transfer favorable alleles found in wild species.

O maracujazeiro pertence à família Passifloraceae, sendo o gênero Passiflora considerado o de maior importância econômica. O objetivo deste trabalho foi quantificar a diversidade genética entre progênies de maracujazeiro-azedo, a fim de definir possíveis grupos heteróticos, com base em descritores morfo-agronômicos por meio do procedimento Ward-MLM, auxiliando, assim, o avanço de geração no programa de melhoramento genético do maracujazeiro-azedo, via seleção recorrente, em desenvolvimento na Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF). Para isso, avaliaram-se 81 progênies de irmãos completos pertencentes ao terceiro ciclo de seleção recorrente (C03). Foram utilizados 23 descritores, sendo cinco qualitativos e 18 quantitativos. As variáveis quantitativas e qualitativas foram analisadas simultaneamente utilizando o procedimento Ward-MLM para composição dos grupos. Pelo procedimento da função da verossimilhança foi determinado como cinco o número ideal de grupos. A estratégia de classificação Ward-MLM para análise dos dados morfo-agronômicos permitiu a constituição dos cinco grupos em 26, 5, 15, 16 e 19 progênies. Observou-se um distanciamento do grupo III em relação aos demais grupos e a aproximação dos grupos I, II, IV e V. Esse distanciamento do grupo III com os demais grupos pode ser um indicativo de possíveis cruzamentos, visando exploração da heterose, objetivando a piramidização de alelos favoráveis para as características de interesse. O procedimento estatístico Ward-MLM consistiu em uma ferramenta útil para detectar divergência genética e agrupar as progênies utilizando simultaneamente variáveis quantitativas e qualitativas.

Passion fruit belongs to the family Passifloraceae, and the genus Passiflora is regarded the most economically important. The present study aimed to quantify genetic diversity among progenies of sour passion fruit, in order to define potential heterotic groups, based on morpho-agronomic descriptors, using the Ward-MLM procedure. It is useful for generation advancement in the passion fruit breeding program, via recurrent selection, under development at the Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF). For such, 81 full-sib progenies belonging to the third recurrent selection cycle (C03) were assessed. Twenty-three descriptors were used, five of which were qualitative and 18, quantitative. The quantitative and qualitative variables were analyzed simultaneously using the Ward-MLM procedure for the composition of groups. The likelihood function determined that five was the ideal number of groups. The Ward-MLM classification strategy for morpho-agronomic data analysis allowed the formation of five groups into 26, 5, 15, 16 and 19 progenies. A certain distance was observed for group III, compared to the other groups while groups I, II, IV and V showed approximation. This greater distance of group III compared to the other groups may indicate crosses, aiming at the exploitation of heterosis, for the pyramiding of favorable alleles for traits of interest. The Ward-MLM statistical procedure was a useful tool to detect genetic divergence and group progenies using simultaneously quantitative and qualitative variables.

Plantas clonais de Passiflora alata foram submetidas a quatro níveis de sombreamento (0; 25; 50 e 75%) aos 75 dias após o estaqueamento (DAE). Dez dias após, aplicou-se nitrogênio (N) nas dosagens de 0; 25;50; 100 e 200 mg N kg-1 de solo. Verificou-se, aos 175 DAE, interação significativa (p<0,05) entre níveis de sombreamento (NS) e doses de N, para todos os parâmetros fotossintéticos avaliados. Observou-se um aumento na taxa fotossintética líquida com a elevação de NS e de N até a dose de 146 mg N kg-1. A taxa transpiratória apresentou efeito quadrático tanto para NS quanto para N, tendendo a aumentar com o incremento de NS e N até 50% de sombreamento e 137 mg N kg-1, respectivamente. A espessura dos tecidos do mesofilo foliar foi reduzida com a intensificação de NS. Os teores de clorofila a, b e total aumentaram com a elevação de NS e N. Todos os parâmetros de crescimento analisados não apresentaram diferenças significativas (p<0,05) para a interação NSxN. O maior acúmulo de biomassa seca total foi obtido em 69% de sombreamento e na dose de 113 mg N kg-1, ocorrendo um declínio nos NS nas e doses de N subsequentes. Em suma, os resultados demonstraram que o sombreamento moderado (50%), associado a um suprimento moderado de N, promoveu maior eficiência fotossintética e, consequentemente, incremento na biomassa seca, na planta toda.

Passiflora alata clonal plants were submitted to four shading levels (0, 25, 50 and 75%) at 75 days after cutting establishment (DAC). Ten days later, nitrogen (N) was applied at 0, 25, 50, 100 and 200 mg N kg-1 of soil. A significant interaction (p<0.05) was observed between shading levels (SL) and N concentrations for all photosynthetic parameters evaluated at 175 DAC. There was an increase in the net photosynthetic rate with the increase of the SL and the N, up to 146 mg N kg-1 of soil. The transpiration rate showed a quadratic effect for both SL and N, increasing with the rise of SL and N, up to 50% shading and 137 mg N kg-1, respectively. The leaf mesophyll thickness was reduced with SL intensification. The total chlorophyll and chlorophyll a and b content increased with the increase of SL and N. There were no significant differences (p<0.05) in the SLxN interaction, for all growth parameters analyzed. The higher accumulation of total dry biomass was obtained at 69% of shading and 113mg N kg-1, with decline in the highest SL and N levels. The results showed that a moderate shade (50%) combined with an adequate N supply, increase the photosynthetic rate and biomass of the whole plant.

Ornamental hybrids of passion flowers are thoroughly diffused in many countries and used in the decoration of houses and gardens. However, the cultivation of ornamental passion fruits practically unexploited in Brazil. This study aimed at evaluating the growth and blooming of F1 hybrids of Passiflora L. (P. sublanceolata J.M. MacDougal [ex P. palmeri var. sublanceolata Killip] vs. P. foetida var. foetida L.) cultivated in ceramic and concrete pots under different shading levels. The vegetative and flower evaluations were carried out weekly, in clonal cuttings 60 days after rooting. The height, leaf length and width, the number of internodes and leaves and stem diameter were evaluated using a randomized complete design in a factorial scheme which corresponded to two genotypes, two types of pot, three shading levels (25 %, 50 %, 75 %) and seven weeks of evaluation, with four replications. For the variable number of flowers, the same experimental design was adopted. However, the number of evaluations was modified for three periods, but this was not considered for the flower diameter and leaf area. The shading levels of 25 % and 50 % were the most favorable to the growth in height, whereas hybrid genotypes under 25 % shade had greater increase in the number of leaves, internodes and stem diameter, showing tolerance to moderate shade. The higher values for length, width and leaf area were observed at 75 % shade. The greatest number of flowers was verified at 25 % shadow in concrete pots. As for the types of pot, the ceramic ones were more favorable to the growth of hybrid plants during the first weeks of acclimatization to the treatments, and the concrete ones were more propitious to blooming. Thus, the use of hybrid plants in concrete pots for the ornamentation of internal environments is recommended, if they are well illuminated.

O presente trabalho objetivou caracterizar o sistema reprodutivo de Passiflora capsularis L. e P. rubra L. Foram realizadas polinizações controladas in vivo, germinação in vitro do pólen e razão pólen:óvulo (P:O). Nas autopolinizações, polinizações intra-específicas e interespecíficas, P. capsularis apresentou em média 62,5, 68,7 e 48,4% de flores fertilizadas, enquanto em P. rubra a média foi de 67,2, 62,5 e 46,9%, respectivamente. Na germinação in vitro, 52,2% dos grãos de pólen de P. capsularis germinaram, enquanto em P. rubra o percentual foi 64,4%. A razão P:O foi 22,4 para P. capsularis e 27,4 para P. rubra, que as incluiu na categoria de autógamas obrigatórias. Passiflora capsularis e P. rubra podem se reproduzir por autopolinização e polinização cruzada, e cruzamentos entre as duas espécies foram bem sucedidos mesmo com baixa taxa de sucesso (menos de 50%). As características do sistema reprodutivo de ambas as espécies permitem a utilização de maiores opções de métodos de melhoramento para produção de plantas ornamentais de Passiflora.

This study aimed to characterize the reproductive system of Passiflora capsularis L. and P. rubra L. In vivo controlled pollinations, in vitro pollen germination and pollen-ovule (P:O) ratio evaluation were conducted. In self-pollination, intraspecific and interspecific pollination, P. capsularis showed means of 62.5, 68.7 and 48.4% of fertilized flowers, while in P. rubra, the averages were 67.2, 62.5 and 46.9%, respectively. For in vitro germination, 52.2% of P. capsularis pollen grains germinated while in P. rubra, the percentage was 64.4. The P:O ratio was 22.4 for P. capsularis, and 27.4 for P. rubra, which included them in the category of obligatory autogamous. Passiflora capsularis and P. rubra can reproduce both by self-pollination and cross-pollination, and crossings between the two species succeeded though the success rate was lower than 50%. The characteristics of the reproductive system of both species allow the use of greater range of options on breeding methods for production of ornamental Passiflora plants.

(Hibridação entre espécies silvestres de passifloras). As passifloras são apreciadas por seu valor ornamental, pois suas flores são vistosas e com enorme diversidade de cores, e muitos híbridos têm sido produzidos e utilizados em outros países. As fontes para seleção de plantas com características ornamentais são progênies híbridas utilizadas em variadas estratégias de cruzamentos. Assim, os objetivos do trabalho foram obter híbridos interespecíficos, realizar retrocruzamentos e obter progênies de cruzamentos entre híbridos e, desta forma, verificar a compatibilidade reprodutiva entre os genitores envolvidos. Foram registrados o percentual de flores fertilizadas e de germinação, além do número de frutos, de sementes e de plantas obtidos por cruzamento. Realizaram-se 374 hibridações envolvendo sete espécies e dois híbridos. Cruzamentos como Passiflora gibertii N. E. Brown vs. P. kermesina Link & Otto e P. gibertii vs. P. alata Curtis produziram frutos que não formaram sementes. Para o cruzamento entre P. gardneri Mast. vs. P. cincinnata Mast. registrou-se o maior percentual de flores fertilizadas (86%), porém as sementes produzidas não apresentaram endosperma. Foram obtidos híbridos interespecíficos dos cruzamentos P. gardneri vs. P. alata, P. watsoniana Mast. vs. P. alata, P. watsoniana vs. P. gardneri e P. gardneri vs. P. gibertii. Sementes geradas de retrocruzamentos envolvendo os híbridos P. sublanceolata (sin. P. palmeri var. sublanceolata (Killip) J. M. MacDougal) vs. P. foetida var. foetida (HD13-133 e HD13-141) e F2 atingiram elevados valores percentuais de germinação.

(Hybridization among wild passionflower species). Passion fruits are appreciated for their ornamental value, since their flowers are showy and display a wide variety of colors. In addition, many hybrids have been produced and used in other countries. The genotypes used in selection of plants with ornamental characteristics are hybrid progenies which are used in various crossing strategies. Thus, the aim of this work was to obtain interspecific hybrids, perform backcrossing and obtain progenies from crossings between hybrids, and to determine the reproductive compatibility between the progenitors involved. The percentage of fertilized flowers, germination, and the number of fruits, seeds and plants obtained through crossing were recorded. A series of 374 crossings involved seven species and two hybrids. Crossings such as Passiflora gibertii N. E. Brown vs. P. kermesina Link & Otto and P. gibertii vs. P. alata Curtis did not produce seeds. The largest percentage of fertilized flowers (86%) was recorded for the crossing P. gardneri Mast.vs. P. cincinnata Mast.; yet, the seeds produced did not show endosperm. Interspecific hybrids were obtained from the crossings P. gardneri vs. P. alata, P. watsoniana Mast.vs. P. alata, P. watsoniana vs. P. gardneri and P. gardneri vs. P. gibertii. Seeds generated from backcrossings involving the hybrids P. sublanceolata (sin. P. palmeri var. sublanceolata (Killip) J. M. MacDougal) vs. P. foetida var. foetida L. (HD13-133 and HD13-141) and F2 reached high germination percentages.