Salinity problems are increasing in the semi-arid regions of northeastern Brazil. Thus, detailed studies of the region’s cultured crops, primarily salt-tolerant species, are important. Therefore, the aim of the present study was to evaluate the salt stress tolerance of lima bean (Phaseolus lunatus L.) seeds at different temperatures. This study was conducted in the Seed Analysis Laboratory, Agricultural Sciences Center, Federal University of Paraíba (Areia, PB, Brazil) by using seeds of four lima bean cultivars (Branca, Orelha de Vó, Rosinha, and Roxinha) in a randomized experimental design. Sodium chloride (NaCl) was used as a solute for salt-stress simulation at the following concentrations: 0.0 (control), 1.5, 3.0, 4.5, 6.0, 7.5, and 9.0 dS m-1; temperatures were maintained constant at 25°C, 30°C, and 35°C. Germination and vigor tests were performed to evaluate the treatment effects (first count, germination rate index, seedling length, and dry matter). Germination rate of lima bean seeds increased in salt concentrations up to 9 dS m-1, and seeds of Roxinha cultivar exhibited the highest salinity tolerance. The development of lima bean cultivar seedlings was negatively affected at 35°C under high-salinity conditions.

The demand for vegetable seeds with high quality and the achievement of vigorous seedlings is increasing, because these characteristics determine the success of the production. The use of some areas such as arid and semiarid regions runs into some obstacles such as salinity and potential sodicity of water used for irrigation, whose main purpose is to provide adequate moisture for growth and development of plants in order to increase productivity and consequently, reduce the effects of drought. This study aims to assess the seed germination and vigor of broccoli (Brassica oleracea L. var. itálica) cv. Santana, under the influence of salt stress. The experiment was conducted at the Laboratory of Analysis of Seeds and Seedlings of the Centro de Ciências e Tecnologia Agroalimentar da Universidade Federal de Campina Grande, PB-Pombal, in completely randomized design, with treatments arranged in 2x5 factorial scheme, corresponding to two lots of seeds (not aged and aged) and osmotic potentials of five soaking solution (0, –0.2, –0.4, –0.6 and –0.8 MPa). Seeds were germinated in Petri dishes on two sheets of filter paper moistened with saline (NaCl) at different concentrations and maintained in germination temperature of 20-30º C and photoperiod-eight hours, after were subjected to assessment of their physiological quality through tests of germination and vigor. The presence of salts in the soaking solution resulted in decreased seed vigor as the osmotic potential of the soaking solution has become more negative, indicating that the seeds of broccoli cultivar Santana has low tolerance to salinity

Germination is negatively influenced by water scarcity and by temperatures above or below the optimal range of the species, so it is necessary to know the critical point of absorption for the species or cultivar. The objective of this work was to evaluate the effect of water stress, simulated by solutions of polyethylene glycol 6000 (PEG 6000) at different temperatures, on the germination and vigor of seeds of four cultivars (Branca, Orelha de Vó, Rosinha and Roxinha) of beans (Phaseolus lunatus L.). The water stress simulation was performed using PEG 6000 solutions at concentrations of 0.0, -0.2, -0.4, -0.6, -0.8, -1.0, and -1.2 MPa at temperatures of 25, 30, and 35 ° C. The analyzed variables were percentage of germination at first count, germination speed index, length of aerial part and primary root of seedlings, and dry mass of the respective parts of the seedlings. The seeds of the cultivar Orelha de Vó were more sensitive to water stress, with 88% germinating up to the potential of -0.6 MPa at the tested temperatures. The cultivars Branca, Rosinha, and Roxinha germinated (94, 100, and 100%, respectively) up to the potential of -0.8 MPa. Water stress simulated by PEG (6000) negatively affects seed twinning and seed vigor of bean cultivars.

Seeds with a good physiological quality are essential to high productivity. However, for some seeds, Phaseolus lunatus L., the viability and vigor analyze show deficiency in quality. This work aimed to evaluate the physiological quality of Phaseolus lunatus L. seeds using several vigor tests. The study was realized at the Laboratory of Seed Analysis of the Agricultural Sciences Center of the Federal University of Paraíba, in Areia – PB, Brazil. We used seeds from five cultivars of P. lunatus (Branca, Orelha de Vó, Cearense, Rosinha, and Roxinha). To determine the physiological quality, we measured the water content, the viability and vigor test (germination, emergence, electrical conductivity, tetrazolium, first germination count and emergence, seedling length and dry mass). We used a completely randomized design for seeds evaluation, and the field test was performed in randomized blocks. The water content of P. lunatus did not differ among the cultivars, indicating a uniformity in the percentage of moisture. Also, the percentage and speed of emergency and the dry mass of seedlings did not differ among the varieties. The tetrazolium and electrical conductivity tests indicated that Rosinha cultivar had the worst viability concerning the other cultivars, showing a low percentage of living tissue and lower electrical conductivity. The seeds of Roxinha cultivar had the better physiological quality, and the Cearense cultivar had the worst quality evaluation. We recommend the tetrazolium test but not the electrical conductivity test to evaluate the vigor of P. lunatus.

Crateva tapia L. is a native tree species of the Caatinga biome, with medicinal and allelopathic properties. This study aimed to characterize the biometric and morphological traits of fruits, seeds, seedlings, and young plants of C. tapia, as well as to evaluate the germination pattern of its seeds under different temperatures, in order to understand the reproductive strategies and optimal conditions for its propagation. The results are intended to support conservation efforts, ecological restoration, and the sustainable use of the species within the Caatinga biome. The research was carried out at the Seed Analysis Laboratory of the Federal University of Paraíba, Campus II, Areia–PB, Brazil. The biometric data were obtained from 100 fruits and 100 seeds obtained from eight mother plants. The imbibition curve was determined from the weight of the seeds during 216 h at different temperatures, and the germination test was performed concomitantly. The fruits were morphologically described regarding the external and internal aspects of the pericarp. The seeds were described according to their consistency, color, texture, shape, hilum, and embryo. The fruits of C. tapia vary in size, fresh mass, and number of seeds, characterized as amphisarcidium, indehiscent, and polyspermic. The seeds are small, brown, reniform, and biting, with a cotyledonary embryo with a poorly differentiated hypocotyl–radicle axis, with a well-developed hilum and surrounded by a fleshy mesocarp. The germination of C. tapia seeds is epigeal-phanerocotyledonous; the seedlings have white axial roots containing absorbent hairs.

Cajanus cajan is used as fertilizer or as food for human and animal. Since salinization of soils is a worldwide problem, it is necessary to look for resistant species. Thus, this study aimed to evaluate the effect of NaCl on germination, emergence and vigor of C. cajan. Therefore, seeds of the pintadinho cultivar and five concentrations of NaCl (1.5; 3.0; 4.5; 6.0; and 7.5 dSm-¹) and control were used. A completely randomized design was performed with four repetitions of 50 seeds for each treatment. Data were submitted to analysis of variance, using the F test to compare mean squares, and the polynomial regression analysis for quantitative effects. The progressive addition of salt had no significant effect on germination and emergence of C. cajan seedlings, however it reduced its vigor.