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The objective of this study was to estimate the genetic effects on in vitro germination and development of chili peppers. For this, four genotypes (UFPB-132, -134, -137, and -390) were used as parents. They were crossed in a complete diallel scheme. The parents (4) and hybrid (12) seeds were germinated in glass bottles containing MS media. The following variables were evaluated: seed germination percentage, deformed seedlings percentage, radicle emission percentage, root length, root number, hypocotyl length, hypocotyl width, definitive leaf number, leaf length, and leaf width. The data were submitted to analysis of variance and the means were grouped by the Scott-Knott criteria (P ≤ 0.05). The diallel analysis was performed according to the Griffing method, method I, fixed model. Significant differences for all analysed variables were observed. Additive and non-additive effects were observed influencing the performance of the genotypes in relation to the evaluated variables. The genitor 132 showed the highest general combining ability for almost all evaluated characteristics, except seed germination percentage and deformed seedlings percentage. This study revealed dominance effects are responsible for genotypic variation for almost all evaluated traits. In addition, we found significant reciprocal effects for all studied characters. For the traits to which non-additive variances were important (germination percentage, deformed seedlings percentage, root number, hypocotyl length, hypocotyl width, and definitive leaf number, leaf length, and leaf width), there was an additional opportunity for developing F1 hybrid.

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Poincianella pyramidalis (Tul.) L.P. Queiroz is an endemic Caatinga (Brazilian savannah biome) species that has been exploited for different purposes, although information is necessary about still existing natural populations. The objective of this study was to evaluate the genetic diversity among 20 P. pyramidalis individuals occurring in a population localized in the Caatinga biome of Paraíba State, aiming at seed collection, using RAPD markers. For the DNA extraction, young shoots of the individuals were used, and amplification was carried out using 20 primers. The obtained markers were converted to a binary matrix, from which a genetic dissimilarity matrix was built using the arithmetic complement of Jaccard's coefficient, and the dendrogram was built by the UPGMA analysis. No amplified fragment was monomorphic, resulting in 100% polymorphism of the analyzed population. The mean genetic diversity among the matrices was 63.28%, ranging from 30.9 to 97.7%. Individuals 09 and 17 showed relevant genetic proximity, and thus planting their seedlings at close sites would not be indicated. The population evaluated in this study showed high genetic diversity, originating twelve groups from the UPGMA hierarchical cluster analysis. Based on the results, individuals 09 and 17 can provide plant material for the evaluation of the physiological performance of P. pyramidalis seeds, and the set of individuals of this population has a high genetic diversity that characterizes them as adequate matrices for projects of restoration and conservation of the seed species.

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Abstract The buriti, Mauritia flexuosa, is the most common palm in Brazil, where it has considerable ecological and economic importance. However, few data are available on the phenology of the species, mainly in coastal restinga ecosystems. The present study monitored the reproductive phenology of M. flexuosa in the restinga of Barreirinhas, in the Brazilian Northeast, and investigated the relationship between phenophases and climatic variables. The presence/absence of flowers and fruits was recorded monthly in 25 individuals of each sex between August, 2009, and October, 2012. There was no difference in the phenology of male and female specimens, with flowering and fruiting occurring exclusively in the dry season. We believe that the specific abiotic characteristics of the study environment, such as the intense sunlight and availability of water in the soil, contribute to the reproductive success of M. flexuosa in the dry season, with consequent germination and establishment of seedlings occurring during the subsequent rainy season.

Resumo Popularmente conhecido como buriti, Mauritia flexuosa é a palmeira mais abundante no Brasil, com grande importância ecológica e econômica, porém ainda são poucos os estudos sobre a sua fenologia, não existindo nenhum em ambiente de Restinga. O presente trabalho teve como objetivo estudar a fenologia reprodutiva de M. flexuosa na Restinga de Barreirinhas, no Nordeste do Brasil, verificando como as fenofases se correlacionam com os fatores climáticos. Foram acompanhados mensalmente 25 indivíduos de cada sexo, de agosto/2009 a outubro/2012, verificando a presença/ausência de floração e frutificação. Não houve diferença no padrão fenológico entre indivíduos femininos e masculinos de M. flexuosa, com floração e queda dos frutos exclusivamente na estação seca. Acreditamos que as características abióticas específicas do ambiente estudado, como a forte incidência solar e a disponibilidade de água no solo, contribuíram para o sucesso reprodutivo de M. flexuosa na estação seca, com consequente germinação e estabelecimento de plântulas no período chuvoso.

Assuntos

RESUMO

The buriti, Mauritia flexuosa, is the most common palm in Brazil, where it has considerable ecological and economic importance. However, few data are available on the phenology of the species, mainly in coastal restinga ecosystems. The present study monitored the reproductive phenology of M. flexuosa in the restinga of Barreirinhas, in the Brazilian Northeast, and investigated the relationship between phenophases and climatic variables. The presence/absence of flowers and fruits was recorded monthly in 25 individuals of each sex between August, 2009, and October, 2012. There was no difference in the phenology of male and female specimens, with flowering and fruiting occurring exclusively in the dry season. We believe that the specific abiotic characteristics of the study environment, such as the intense sunlight and availability of water in the soil, contribute to the reproductive success of M. flexuosa in the dry season, with consequent germination and establishment of seedlings occurring during the subsequent rainy season.(AU)

Popularmente conhecido como buriti, Mauritia flexuosa é a palmeira mais abundante no Brasil, com grande importância ecológica e econômica, porém ainda são poucos os estudos sobre a sua fenologia, não existindo nenhum em ambiente de Restinga. O presente trabalho teve como objetivo estudar a fenologia reprodutiva de M. flexuosa na Restinga de Barreirinhas, no Nordeste do Brasil, verificando como as fenofases se correlacionam com os fatores climáticos. Foram acompanhados mensalmente 25 indivíduos de cada sexo, de agosto/2009 a outubro/2012, verificando a presença/ausência de floração e frutificação. Não houve diferença no padrão fenológico entre indivíduos femininos e masculinos de M. flexuosa, com floração e queda dos frutos exclusivamente na estação seca. Acreditamos que as características abióticas específicas do ambiente estudado, como a forte incidência solar e a disponibilidade de água no solo, contribuíram para o sucesso reprodutivo de M. flexuosa na estação seca, com consequente germinação e estabelecimento de plântulas no período chuvoso.(AU)

Assuntos

RESUMO

The buriti, Mauritia flexuosa, is the most common palm in Brazil, where it has considerable ecological and economic importance. However, few data are available on the phenology of the species, mainly in coastal restinga ecosystems. The present study monitored the reproductive phenology of M. flexuosa in the restinga of Barreirinhas, in the Brazilian Northeast, and investigated the relationship between phenophases and climatic variables. The presence/absence of flowers and fruits was recorded monthly in 25 individuals of each sex between August, 2009, and October, 2012. There was no difference in the phenology of male and female specimens, with flowering and fruiting occurring exclusively in the dry season. We believe that the specific abiotic characteristics of the study environment, such as the intense sunlight and availability of water in the soil, contribute to the reproductive success of M. flexuosa in the dry season, with consequent germination and establishment of seedlings occurring during the subsequent rainy season.

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Pepper species exhibit broad genetic diversity, which enables their use in breeding programs. The objective of this study was to characterize the diversity between the parents of different species and their interspecific hybrids using morphological and molecular markers. The parents of Capsicum annuum (UFPB-01 and -137), C. baccatum (UFPB-72), and C. chinense (UFPB-128) and their interspecific hybrids (01x128, 72x128, and 137x128) were used for morphological and molecular characterization. Fruit length and seed yield per fruit (SYF) traits showed the highest variability, and three groups were formed based on these data. CVg/CVe ratio values (>1.0) were calculated for leaf length (1.67) and SYF (5.34). The trait that most contributed to divergence was the largest fruit diameter (26.42%), and the trait that least contributed was pericarp thickness (0.33%), which was subject to being discarded. The 17 primers produced 58 polymorphic bands that enabled the estimation of genetic diversity between parents and hybrids, and these results confirmed the results of the morphological data analyses. The principal component analysis results also corroborated the morphological and random-amplified polymorphic DNA data, and three groups that contained the same individuals were identified. These results confirmed reports in the literature regarding the phylogenetic relationships of the species used as parents, which demonstrated that C. annuum was closer to C. chinense as compared to C. baccatum.

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The aim of this study was to relate flower bud size with microspore developmental stages and the induction of embryos in the anthers of different ornamental pepper (Capsicum annuum L.) genotypes. Flower buds were randomly collected and visually divided into three classes based on both petal and sepal size. The length and diameter of the bud as well as the length of the petal, sepal, and anther were then measured. The microspore stage was also determined for each anther of the bud where it was found. The data were subjected to analysis of variance (P ≤ 0.01), and the means were separated by Tukey's test (P ≤ 0.01). The broad sense heritability, the CVg/CVe relation, and the Pearson correlation between characters were also determined. Anthers from 10 C. annuum genotypes were cultivated in four culture media types for the induction of embryos. The data were transformed by Arcsin (x) and subjected to analysis of variance (P ≤ 0.01), and the means were separated by Tukey's test (P ≤ 0.01). The majority of anthers in the second class had uninucleate microspores. No correlation was observed between bud size and the number of uninucleate microspores. Genotype 9 specimens grown in M2 medium induced the highest number of embryos (16) compared to the other treatments, which indicates a significant interaction effect between culture media and genotypes.

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Brazil has a great diversity of Capsicum peppers that can be used in breeding programs. The objective of this study was to evaluate genetic variation in traits related to the physiological quality of seeds of Capsicum annuum L. in a segregating F2 population and its parents. A total of 250 seeds produced by selfing in the F1 generation resulting from crosses between UFPB 77.3 and UFPB 76 were used, with 100 seeds of both parents used as additional controls, totaling 252 genotypes. The seeds were germinated in gerboxes containing substrate blotting paper moistened with distilled water. Germination and the following vigor tests were evaluated: first count, germination velocity index, and root and shoot lengths. Data were subjected to analysis of variance, and means were compared by Scott and Knott's method at 1% probability. Tocher's clustering based on Mahalanobis distance and canonical variable analysis with graphic dispersion of genotypes were performed, and genetic parameters were estimated. All variables were found to be significant by the F test (P ≤ 0.01) and showed high heritability and a CVg/CVe ratio higher than 1.0, indicating genetic differences among genotypes. Parents (genotypes 1 and 2) formed distinct groups in all clustering methods. Genotypes 3, 104, 153, and 232 were found to be the most divergent according to Tocher's clustering method, and this was mainly due to early germination, which was observed on day 14, and would therefore be selected. Understanding the phenotypic variability among these 252 genotypes will serve as a basis for continuing the breeding program within this family.

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Two accessions of ornamental pepper Capsicum annuum L., differing in most of the characters studied, were crossed, resulting in the F1 generation, and the F2 generation was obtained through self-fertilization of the F1 generation. The backcross generations RC1 and RC2 were obtained through crossing between F1 and the parents P1 and P2, respectively. Morpho-agronomic characterization was performed based on the 19 quantitative descriptors of Capsicum. The data obtained were subjected to generation analysis, in which the means and additive variance (σa(2)), variance due to dominance deviation (σd(2)), phenotypic variance (σf(2)), genetic variance (σg(2)) and environmental variance (σm(2)) were calculated. For the full model, we estimated the mean effects of all possible homozygotes, additives, dominants, and epistatics: additive-additive, additive-dominant, and dominant-dominant. For the additive-dominant model, we estimated the additive effects, dominant effects and mean effects of possible homozygotes. The character fruit dry matter had the lowest value for broad sense heritability (0.42), and the highest values were found for fresh matter and fruit weight, 0.91 and 0.92, respectively. The lowest value for narrow sense heritability was for the minor fruit diameter character (0.33), and the highest values were found for seed yield per fruit and fresh matter, 0.87 and 0.84, respectively. The additive-dominant model explained only the variation found in plant height, canopy width, stem length, corolla diameter, leaf width, and pedicel length, but in the other characters, the epistatic effects showed significant values.

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The objective of this study was to determine the effects of the general and specific combining abilities (GCA and SCA, respectively) of 15 characteristics and to evaluate the most promising crosses and the reciprocal effect between the hybrids of six parents of the Capsicum annuum species. Six parents, belonging to the Horticultural Germplasm Bank of Centro de Ciências Agrárias of Universidade Federal da Paraíba, were crossed in complete diallel manner. The 30 hybrids generated and the parents were then analyzed in a completely randomized design with three replicates. The data were submitted to analysis of variance at 1% probability, and the means were grouped by the Scott-Knott test at 1% probability. The diallel analysis was performed according to the Griffing method, model I and fixed model. Both additive and non-additive effects influenced the hybrids' performance, as indicated by the GCA/SCA ratio. The non-additive effects, epistasis and/or dominance, played a more important role than the additive effects in pedicel length, pericarp thickness, fresh matter, dry matter content, seed yield per fruit, fruit yield per plant, days to fructification, and total soluble solids. The GCA effects were more important than the SCA effects in the fruit weight, fruit length and diameter, placenta length, yield, vitamin C, and titratable acidity characteristics. The results found here clearly show that ornamental pepper varieties can be developed through hybridization in breeding programs with C. annuum.

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