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Most commercial plantations of passion fruit is propagate plants by seed, but germination is irregular, which hinders the growth of seedlings and uniformity, and is connected with the plant genotype. The objective of this study was to evaluate the germination and early growth of passion fruit hybrid seedlings, obtained from different genetic combinations. The hybrids were obtained from the cross between progenies from the breeding program of the Universidade Federal de Viçosa with hybrids of the Empresa Brasileira de Pesquisa Agropecuária and of the Viveiros Flora Brasil. The experimental design was completely randomized with six hybrids, five replicates and fifty seeds per experimental unit. Germination was assessed daily until the 28 days, and at the end of the period it was obtained the mean time germination, emergence speed index, seedling height, the length of shoots and roots, and the individual seedling dry matter (root + shoot)was assessed. Among the passion fruit hybrids evaluated, hybrid HB2 (UFVM0212 × BRS Sol do Cerrado) showed the highest germination and seedling biometric values and might be a genotype with potential for breeding programs for seed quality. The specific combining ability of parents can influence the quality of seeds and the vigor of passion fruit seedlings. A factor must be considered is the correct choice of maternal and paternal parents, since they influence the quality of seeds.Keywords: biometrics, combining ability, emergency, Passiflora edulis Germinação de sementes e vigor de híbridos de maracujazeiro ResumoA maioria das plantações comerciais de maracujazeiro é propagada por sementes, mas a germinação é irregular, o que dificulta o crescimento das mudas e sua uniformidade, e está ligado ao genótipo da planta. Objetivou-se no trabalho, avaliar a germinação e o crescimento inicial em plântulas de híbridos de maracujazeiro, obtidos de diferentes combinações genéticas. Os híbridos foram obtidos do cruzamento de progênies do programa de melhoramento da Universidade Federal de Viçosa com híbridos comerciais da Empresa Brasileira de Pesquisa Agropecuária e do Viveiro Flora Brasil. O delineamento experimental utilizado foi o inteiramente casualizado, com seis híbridos, cinco repetições e cinquenta sementes por unidade experimental. A germinação foi avaliada diariamente até 28 dias, e ao final do período foi obtido o tempo médio de germinação, o índice de velocidade de emergência, a altura da planta, o comprimento da parte aérea e da raiz e massa seca individual das plântulas (raiz + parte aérea). Entre os híbridos de maracujazeiro avaliados, o híbrido HB2 (UFVM0212 × BRS Sol do Cerrado) apresentou os maiores valores de germinação e biométricos de mudas e pode ser um genótipo com potencial para programas de melhoramento para qualidade de semente. A capacidade específica entre os pais pode influenciar a qualidade das sementes e o vigor das mudas de maracujazeiro. Um fator que deve ser considerado é a escolha correta dos pais maternos e paterno, uma vez que eles influenciam a qu...

Guava is an important fruit in Brazil and worldwide. However, research has yet to advance on its breeding and seed technology, an essential factor for the development of productive genotypes with germination potential which would support the continuity of breeding programs. In search of a methodology for routine analysis testing of guava seeds under genetic control, this study examined the effect of temperature and substrate on the germination of guava seeds from full-sib families. The experiment was laid out in a completely randomized design with a 5 × 4 factorial arrangement consisting of the combination of five temperatures (25, 30, 35, 20-30 and 25-35 °C) and four substrates (paper roll, on-paper, in-sand and on-sand), with eight replicates of 50 seeds. Germination, germination speed index and live ungerminated seeds were evaluated. The alternating temperatures of 20-30 and 25-35 °C and the paper roll, on-paper and in-sand substrates are adequate conditions for germination tests with guava seeds.

-The propagation of passion fruit in commercial orchards is carried out by seeds. However, passion fruit seed germination occurs irregularly. The goal of this study was to evaluate the emergence and development of passion fruit seedlings under different luminosities and sowing depths. The experimental design was completely randomized with six replications of 25 seeds, with a 3 x 5 factor scheme, in which three light conditions (absence of light, presence of 12 h light and 12 h dark and the presence of light for 24 h) were combined with five sowing depths (1, 2, 3, 4 and 5 cm). The emergence test was conducted in a BOD-type germination chamber, with alternating temperatures of 20-30 °C, at intervals of 12 h and the established luminosities. The evaluated characteristics were the emergence percentage for weekly counts, the emergence speed index for 28 days; the total shoot and root length on evaluation day 28 and the individual dry weight. The lack of luminosity accelerates the emergence of passion fruit seedlings, but it produces low quality seedlings. However, the alternation of luminosity associated to a lower sowing depth helps both the emergence and the quality of seedlings produced from passion fruit 14 days after sowing.

Guava is of great economic importance in Brazil. The development of new cultivars by obtaining inbreeding lines has been a promising option. The objective of this work was to evaluate the S 2 families of Psidium guajava using seed attributes. Different characters of physiological quality of guava seeds were studied, in addition to performing digital phenotyping of characteristics of geometry, texture and colors of the seeds. The variables were analyzed simultaneously using the Ward-Modified Location Model (MLM) method and carried out individual analyses of variance for estimating genetic parameters of the population. The formation of more than one group of divergent genotypes was observed, the geometry characteristics were more impacting for the discrimination of the genotypes, a high phenotypic correlation was observed with the germination variables and dry matter weight. High heritabilities were verified for the variables related to seed quality, indicating success in selecting vigorous genotypes. The Ward-MLM method is a useful tool to detect genetic diversity among genotypes of inbred guava. Thus, the most divergent genotypes with high germination potential can be recommended for future crosses or self-fertilized to obtain new lines in the guava breeding program.

Resumo -Os pomares comerciais e domésticos de pitangueira, em sua maioria, são formados por plantas propagadas através de sementes. As informações sobre as exigências das sementes de pitanga quanto às exigências de fotoperíodo para que ocorra a germinação são mínimas. O trabalho teve como objetivo avaliar a emergência de plântulas de pitangueira sob fotoperíodo. O experimento foi conduzido em delineamento inteiramente casualizado, com três tratamentos (ausência de luz; fotoperíodo de 12 h e luz constante) e quatro repetições em câmara climatizada. A emergência foi avaliada do 18º até o 60º dia e, ao final do experimento, foi avaliado o tempo médio de emergência, o índice de velocidade de emergência, a altura das plântulas, comprimento de raiz e parte aérea e massa seca das plântulas. O fotoperíodo não interfere na percentagem de emergência de plântulas de pitangueira. No entanto, na ausência de luz, o índice velocidade de emergência foi maior. A massa seca das plântulas submetidas à presença constante de luz foi significativamente superior à massa observada nas condições de ausência de luz e fotoperíodo de 12 horas. A emergência das plântulas de pitangueira ocorre tanto na ausência quanto na presença de luz. A pitangueira pode ser considerada como fotoblástica neutra para emergência de plântulas.Palavras-chave: Germinação de Sementes; Fotoblastismo; Myrtaceae. Emergence of surinan cherry (Eugenia uniflora L.) seedlings under different photoperiodsAbstract -The commercial and domestic orchards of surinan cherry, for the most part, are formed by plants propagated through seeds. Information on the requirements of surinan cherry seeds for photoperiod requirements for germination is minimal. The objective of this work was to evaluate the emergence of surinan cherry seedlings under photoperiod. The experiment was conducted in a completely randomized design, with three treatments (absence of light, 12 h photoperiod and constant light) and four replications in a heated room. The emergence was evaluated from the 18 th to the 60 th day and at the end of the experiment the mean time of emergence, the rate of emergence, seedling height, root length and aerial part and dry mass of the seedlings were evaluated. The photoperiod does not interfere with the percentage of emergence of surinan cherry seedlings. However, in the absence of light, the rate of emergence was higher. The dry mass of the seedlings submitted to the constant presence of light was significantly higher than the mass observed in the conditions of absence of light and photoperiod of 12 hours. The emergence of surinan cherry seedlings occurs both in the absence and in the presence of light. The surinan cherry can be considered as neutral photoblastic for emergence of seedlings.Keywords: Seed germination; Photoblastism; Myrtaceae. Emergência de plântulas de pitangueira (Eugenia uniflora L.) sob diferentes fotoperíodos Cremasco et al.

Guava, Psidium guajava L., is a species of economic importance for several countries. The production of new varieties of guava from seeds with good germination and vigor potential has been investigated. In this scenario, the present study characterized and estimated the genetic diversity of seeds of 42 genotypes of guava from an S2 family based on germination response, vigor tests, and digital phenotyping analysis. The experiment was laid out in a randomized-block design with four replicates. Descriptive statistics were carried out for each of the analyzed variables and multivariate analyses were used to estimate genetic diversity based on Gower's Distance. Digital analysis was performed using the GroundEye S120 system, which extracted color, geometry, texture, and histogram data. In total, three color, two geometry, five texture, four physiological analysis, and 17 histogram variables were used. The physiological variables and those obtained by digital phenotyping were efficient to discriminate the genotypes, indicating that there is genetic variability to be exploited within the guava breeding program. The traits that most contributed to genetic diversity were those related to the histogram. The genotypes belonging to groups I and III had the highest means for germination percentage, thousand-seed weight, and shoot length. Based on the results, two options are viable for conducting the guava breeding program. The most vigorous individuals can be self-pollinated for the development of lines and the superior and most divergent ones from groups I and III can be crossed to exploit heterosis. Thus, crosses between the most vigorous individuals from groups I and III are recommended, as they exhibited higher means for the traits of germination percentage, thousand-seed weight, and shoot length.

Anthurium solitarium Schott is a species that might be used both as potted plant and cut foliage, but it is indispensable to have an adequate substrate to achieve desirable growth and commercial standard. Thus, the present research aimed at evaluating the ornamental potential and commercial quality of Anthurium solitarium grown in bamboo compost. The experimental design was in randomized blocks, with six substrates and three replicates with five plants in each experimental plot. Seedlings were grown for 270 days in substrates containing different percentages (v:v) of bamboo compost (BC) and coconut fiber (CF): T1 (100% CF), T2 (75% CF + 25% BC), T3 (50% CF + 50% BC), T4 (25% CF + 75% BC), T5 (100% BC); and a control treatment, T6 -commercial substrate Basaplant ® (100% CS). The number of leaves, the leaf area, leaf (LDW) and root dry weight (RDW), root length and volume, LDW/RDW ratio and total dry weight. Leaf nutrient contents were determined. The ornamental potential, commercial acceptance and quality of the plants were also evaluated. Plants grown in substrates with BC showed higher growth, ornamental potential, market quality and acceptance than those grown in CF and CS.