Caroline Marques Rodrigues

In forest species with physical dormancy, defining the ideal harvest point is challenging because of the limited understanding of the relationships among maturation, physiological quality, and seed dormancy. Hymenaea martiana Hayne, a native species of the Caatinga (Brazil) biome with ecological and economic relevance and potential for use in restoration, still requires integrated information on these processes. This study aimed to identify the point of physiological maturity and the moment of establishment of physical dormancy in H. martiana seeds on the basis of the associations between fruit color and indicators of physiological quality. The experiment was conducted in a completely randomized design with a 6 × 2 factorial scheme (maturation stages × with and without scarification), and the physical characteristics and physiological quality of the seeds were evaluated. The data were analyzed using univariate and multivariate approaches, with inflection point analysis applied as a complementary method to identify structural changes throughout maturation. Maturation is characterized by a reduction in water content, accumulation of dry matter, and the progressive establishment of physical dormancy. Seed coat dormancy is the main limiting factor for germination, and it is efficiently overcome by mechanical scarification, which confirms the role of seed coat impermeability in controlling imbibition and seedling emergence. Stage V represents the most suitable harvest point under the conditions evaluated, at which point the seeds exhibit physiological maturity associated with the greatest expression of vigor and the best germination performance when subjected to scarification. Defining this interval as the ideal harvest point contributes to improving seed collection and handling strategies, particularly for seedling production.

Viviparity is rarely reported in species with seed physical dormancy. This is because physical dormancy, common in tropical trees, results from the impermeability of the seed tegument to water and regulates the timing of germination. Records of germination within the fruit in such species suggest greater functional plasticity than traditionally assumed. This study reports and quantifies viviparity in Hymenaea martiana seeds over four consecutive years (2019–2022) and assessed seed dormancy status through vigor tests. Sixty fruits were collected annually, and viviparity was estimated as the proportion of fruits containing at least one seed with radicle protrusion. Non-viviparous seeds were subjected to emergence tests with and without mechanical scarification, and cumulative emergence, percentages of dead and water-impermeable seeds, and seed water content were evaluated. Viviparity occurred consistently, affecting approximately 10–15% of the fruits, with no significant differences between years, indicating that the phenomenon was not associated with extreme environmental events. However, early germination did not result in seedling establishment because the emerging roots dehydrated while still inside the fruit. Mechanical scarification significantly increased emergence, confirming the presence of seed physical dormancy. These results show that, although viviparity was observed recurrently in the studied population of H. martiana, seed physical dormancy remains the main mechanism controlling germination in this species.

The aim of this study was to assess phenotypic variation and its implications for genetic diversity in natural populations of Spondias tuberosa. Fruits were harvested from 38 mother plants from three natural populations, and the physical traits of the fruits, endocarps, and physiological quality of the seeds were evaluated in a completely randomized design with four replicates of 25 fruits per genotype. The data were subjected to analysis of variance, and the means were grouped via the Scott–Knott method. Genetic diversity was evaluated via UPGMA and Tocher clustering methods, which are based on the Mahalanobis distance (D²) and canonical variables, whereas the relative importance of the characters was evaluated via the Singh method. The results indicated high phenotypic variability, with fruit length was the main discriminant trait among genotypes. The groupings formed six (UPGMA) and 12 groups (Tocher), indicating greater divergence within populations. The analysis of phenotypic data provides a solid basis for understanding the ecological dynamics of and supporting sustainable management practices for S. tuberosa, in line with bioeconomic objectives. This study highlights the importance of preserving phenotypic variability in populations, which is essential for the adaptation of species to environmental changes and for improving local bioeconomies.

Phenological studies are fundamental for species management and conservation and support research into genetic improvement by providing insights into plant life cycles and their relationship with phenophases and environmental conditions. This study aimed to determine the environmental variables and their influence on the vegetative and reproductive phenological patterns of Hymenaea martiana Hayne. Field observations were carried out in five areas located in the municipality of Areia, Paraíba State, Brazil. Between May 2021 and April 2023, the phenological events of budding, senescence, flower bud, flowering, and fruiting were assessed every 30 days. Statistical analyses were circular to verify the occurrence of the phenophase periods, their concentration, seasonality, and duration, and Spearman correlations were used to test the relationships between meteorological variables during the period and the phenophases. The patterns of budding, senescence, flower bud, and flowering phenophases of H. martiana were seasonal, with an annual periodicity and a continuous fruiting pattern. The average dates of occurrence of the budding phenophase were August (area 2), October (areas 1, 4, and 5), and November (area 3). The average date for senescence was July (area 2) and August (areas 1 and 3–5). The average date for the flower bud phase was November (area 5) and December (areas 1–4). Flowering occurred in January (areas 3 and 4), March (area 2), and December (areas 1 and 5). Rainfall and temperature had a significant impact on the period and occurrence of vegetative and reproductive phenological events in H. martiana. Under highland marsh conditions, H. martiana fruit should be collected in October, November, and December.

Hymenaea martiana is a species native to Brazil. It has ecological value, contributes to forest restoration, and is economically important because of the use of its wood and fruits. However, it is frequently exploited. Therefore, understanding genetic diversity becomes essential for guiding conservation strategies as well as ecological restoration actions in the face of climate change and anthropogenic pressures. Thus, this study aimed to evaluate the intraspecific diversity of 160 H. martiana mother plants on the basis of morphological descriptors of fruits and seeds and physiological indicators of seed quality, identifying the most discriminating characters. Eighteen traits were analyzed and subjected to analysis of variance and the Scott–Knott test (p < 0.05), with estimates of heritability and the ratio between genetic and environmental coefficients of variation. Phenotypic divergence was obtained via the Mahalanobis distance (D²) and grouped via UPGMA, whereas the relative contribution of the traits was estimated via the Singh method. The results revealed that seed length and weight, emergence speed index, and shoot dry mass were the most effective descriptors for discriminating parent plants. Multivariate analysis revealed the formation of eleven phenotypically distinct groups, demonstrating high variability. These findings support the selection of superior genotypes and representative seed collection, as well as practical initiatives such as the formation of germplasm banks, the selection of breeding stock for forest nurseries, and reintroduction programs. Thus, the data obtained offer technical and scientific support for biodiversity conservation and ecosystem recovery in the semiarid region of Brazil.

The Brazilian Atlantic Forest is recognized as a biodiversity hotspot with high levels of Cactaceae endemism, attracting significant attention for conservation efforts

Crateva tapia L. é uma espécie nativa, indicada para programas de recuperação de áreas degradadas e reflorestamento, porém, para o sucesso desses programas é necessário fazer uso de sementes de qualidade e, na avaliação do seu vigor tem-se o teste de envelhecimento acelerado. Assim, objetivou-se nesse trabalho adaptar a metodologia do teste de envelhecimento acelerado para sementes de C. tapia, expostas a diferentes condições. O trabalho foi desenvolvido no Laboratório de Análise de Sementes (LAS), no CCA, UFPB, Campus II. O experimento foi conduzido em delineamento inteiramente ao acaso, com os tratamentos distribuídos em esquema fatorial 5 x 3, correspondente a cinco períodos de exposição das sementes ao envelhecimento acelerado (0, 24, 48, 72 e 96 horas) e três temperaturas (41, 43 e 45 °C). As variáveis analisadas foram grau de umidade e a qualidade fisiológica das sementes. O grau de umidade das sementes aumentou independentemente da temperatura, em função dos períodos de envelhecimento. A máxima porcentagem de germinação ocorreu quando as sementes foram envelhecidas na temperatura de 45 °C (94,6%), mas reduziu em função dos períodos de envelhecimento. O tempo e a velocidade média de germinação não foram influenciados pelas soluções de envelhecimento. O aumento da temperatura e dos períodos de envelhecimento, reduziu até 36% no comprimento de plântulas. O teste de envelhecimento acelerado conduzido na temperatura de 45 °C por 24 h é a combinação adequada para avaliar o vigor das sementes de C. tapia.

Seed quality is essential for developing conservation, management, and ecological restoration techniques, selecting highquality seed lots, and understanding the genetic variability of species. Thus, the objective of this study was to evaluate the physiological quality of seeds from 80 mother trees in a natural population of Hymenaea martiana in Areia, Paraíba, Brazil. Seed vigor was assessed based on traits related to emergence and early seedling development. The data were subjected to analysis of variance (ANOVA), with means compared using the Scott-Knott test at a 5% significance level, and complemented by Pearson correlation and Principal Component Analysis (PCA). Mother trees M86, M145, M157, M171, M184, and M187 demonstrated superior performance in emergence traits, while M8, M86, M88, M117, and M152 exhibited greater shoot length. Mother trees M10, M11, M12, M14, M21, M24, M73, and M152 produced seedlings with greater root length, while M187 produced seedlings with higher root dry weight. In PCA, three principal components explained 81.63% of the total data variance, with emergence traits contributing most to PC1, mean emergence time to PC2, and root length and dry weight to PC3. In this context, the evaluated natural population of H. martiana mother trees exhibited variability in seed physiological quality, primarily driven by first emergence count, emergence speed index, and final emergence percentage.

The success of reforestation depends on seed quality, making it essential to assess their physiological potential. This evaluation can be carried out through vigor tests, such as the exudate pH test, which is considered quick and cost-effective. The objective of this study was to evaluate the exudate-phenolphthalein pH test in assessing the viability of seed lots of Crateva tapia L. A completely randomized design in a 2 × 5 × 5 factorial scheme was used, with two temperatures (20 and 30 °C), five soaking periods (30, 60, 90, 120, 150 min), and five seed lots (I: matrix 0, II: matrix 99, III: matrix 100, IV: matrix 101 from Juarez Távora, and V: matrix Remígio). In the Seed Analysis Laboratory, the physical and physiological characteristics of the seeds were determined, followed by exudate pH and germination tests to verify the results. The data were subjected to analysis of variance, and the means were grouped by the Scott-Knott test. Lot I showed the lowest vigor, a result confirmed by the exudate pH test. The tests for first count, percentage, and germination speed index were effective in evaluating seed lot quality. The pH test, conducted at 20 °C for 30 min, proved efficient in analyzing seed viability.

Species like Crateva tapia, valued for its ecological and nutritional importance, with discontinuous flowering and fruiting, make it challenging to anticipate the harvest time of fruits and determine the physiological maturity of seeds due to the variety of maturation stages on a single plant. Thus, the objective in this study was to determine the physiological maturity of C. tapia seeds. A completely randomized design was used, in a split plot scheme with four replicates. In the plots was evaluated the production cycles 2020-2021 (cycle I) and 2021-2022 (cycle II), and in the split plot was evaluated the maturation stages: 25, 40, 55, 70, 85, 100, 115, 130, 145, 160, and 175 days after anthesis. The evaluated characteristics included the physical (fruit and seeds) and physiological (seeds) traits throughout their development. As the fruits matured, their color changed from deep green to yellow, while the seeds transitioned from pink to dark brown. The seeds reached maximum germination capacity and vigor at 153 and 126 days in cycle I, respectively, and at 149 and 136 days after anthesis in cycle II, respectively. C. tapia seeds reach physiological maturity between 142 and 150 days after anthesis. Morphological aspects of the fruits, such as green coloration with small yellow traces, indicate the physiological maturation of the seeds. The development of C. tapia seeds involves morphological and physiological changes that affect their quality and germination capacity. Climatic conditions (temperature and precipitation) during seed formation influence the germination process and vigor.