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The biometric differences between fruits and seeds are useful characteristics that can provide important data for the investigation and preservation of the species and may be linked to environmental and genetic influences. In this sense, considering the importance of this species and the need for conservation, the objective was to carry out physical characterization of the fruits and seeds of Hymenaea martiana as well as to determine the seed imbibition curve. The experiment was conducted at the Seed Analysis Laboratory at the Agricultural Sciences Center at the Federal University of Paraíba in Areia, PB. The evaluations carried out were as follows: biometry of fruits and seeds, number of seeds per fruit, colorimetry of fruits and seeds, percentage of damaged seeds, weight of a thousand seeds, seed water content, mass and imbibition curve. The biometric data were subjected to descriptive analysis to determine the minimum, maximum, average value, standard deviation, asymmetry, and kurtosis of the fruits and seeds. In terms of the biometric characteristics of the fruits and seeds of H. martiana, there was a marked variation, with average fruit lengths of 90.28 mm, widths of 46.83 mm, thicknesses of 34.69 mm, weights of 65.86 g and four seeds per fruit. The average length, width, thickness and weight of the seeds were 23.75 mm, 18.34 mm, 12.71 g and 4.13 g, respectively. The fruits were darker than the seeds, and both the fruits and seeds had red tones. Compared with nonscarified seeds, scarified seeds absorb a greater amount of water.

‘Faveira’ (Dimorphandra gardneriana Tul.) is a medicinal plant of great commercial value, primarily due to its ability to produce rutin on a global scale. Furthermore, it serves as a source of raw materials for the extraction of other secondary metabolites. With this, this study aimed to standardize the methodology of the tetrazolium test and evaluate its applicability in estimating the viability of seeds from different parent plants of faveira. The viability and vigor of the seeds were determined using tetrazolium (2, 3, 5-triphenyl-tetrazolium chloride) in four concentrations (0.025, 0.050, 0.075, and 0.1%) and four immersion periods: 30, 60, 90, and 120 min, with the viability percentage and vigor levels being considered according to the topological staining pattern. Germination and seedling emergence tests were also conducted. The most suitable preparation for D. gardneriana seeds is preconditioning for 78 hours at 25 °C, followed by cutting in the region opposite the embryo. The tetrazolium test efficiently assesses the viability and vigor of D. gardneriana seeds, whose ideal seed color is obtained using a 0.075% tetrazolium solution for 120 min at 40 °C. In 20 parent plants, the seeds from the parent plants 2, 3, 6, 8, 9, 12, and 13 stood out as the most vigorous.

Crataeva tapia L. is a fruit native to the Brazilian savanna, the Caatinga, and is used in the production of soft drinks and other beverages. Given the importance of this species and the lack of knowledge about its seeds, this research aimed to evaluate the physiological quality of C. tapia L. seeds subjected to different environments and drying periods. Seeds were dried for the following time periods: 0 (no drying), 24, 48, 72, 96, and 120 hours, in the laboratory environment (25°C and 90% RH) and in a greenhouse (30°C and 80% RH). After the drying period, seeds from each of the treatments were used for determining the water content, germination, and vigor (using tests for emergence, first count of germination and emergence, rate of germination and emergence, length, and seedling dry weight). The experimental design was completely randomized and a factorial 2×6 scheme (local environment × drying periods) was used with four replicate sets of seeds. The data were subjected to analysis of variance and polynomial regression using quadratic models. The germination and seed vigor reduced as the drying periods increased. For optimum results, the seeds of C. tapia L. must be dried in the laboratory for a period of 48 hours. In addition, their desiccation resistance was classified as intermediate.

O objetivo neste trabalho foi avaliar a eficiência de diferentes métodos para a superação da dormência em sementes Dimorphandra gardneriana Tulasne, visando fornecer conhecimentos técnico-científicos que permitam a criação de um protocolo de germinação. Em um experimento realizado no Laboratório de Análise de Sementes do Centro de Ciências Agrárias da Universidade Federal da Paraíba (CCA-UFPB), em delineamento experimental inteiramente ao acaso, as sementes de D. gardneriana foram submetidas aos seguintes tratamentos: testemunha que consistiu de sementes não escarificadas, sementes escarificadas mecanicamente com lixa n° 120, sementes escarificadas mecanicamente com lixa e submetidas à embebição em água destilada por 6, 12, 18 e 24 horas, sementes submetidas ao desponte na região oposta ao hilo com alicate de unha, sementes submetidas ao desponte na região oposta ao hilo com alicate de unha e postas em embebição em água destilada por 6, 12, 18 e 24 horas, escarificação química com ácido sulfúrico concentrado por 5, 10 e 15 minutos. Após a aplicação dos tratamentos as sementes foram submetidas a testes de germinação e vigor (emergência, índice de velocidade de germinação e de emergência, comprimento e massa seca de hipocótilo e raízes). A escarificação mecânica com lixa e o desponte seguidos de imersão em água destilada por seis horas favorecem a porcentagem de germinação de sementes e emergência de plântulas de Dimorphandra gardneriana, e os tratamentos utilizando ácido sulfúrico reduziram drasticamente o vigor destas sementes.

Convolvuloideae is a group of plants formed by genera with n = 15 and high stability of chromosome numbers. Despite being stable, polyploidy is the main mechanism of karyotype evolution for the group and seems to be related to speciation events. The present work aimed to comparatively analyze the karyotypes of diploid species from Convolvuloideae, with emphasis on Ipomoea, using fluorochrome banding and genome size. New counts were recorded for five species belonging to Camonea and Ipomoea, all with 2n = 30. The basic number x = 15 has been suggested for Convolvuloidae. The first genome size records are presented here for the genera Camonea, Distimake and Stictocardia, as well as for six species of Ipomoea. Genome size ranged from 1C = 0.78 pg in I. bahiensis to 1.38 pg in Distimake dissectus. Two types of heterochromatin bands were identified in Convolvuloideae, CMA⁺ bands were the predominant type, while DAPI⁺ bands were less frequent, with four banding variation described. Small genome sizes and stable chromosome numbers possibly represent evolutionarily strategies associated with adaptation and speciation in the clade, while the implications of heterochromatin variation remain unknown.