Non-destructive and high performance analyses are highly desirable and important for assessing the quality of forest seeds. The aim of this study was to relate parameters obtained from semi-automated analysis of radiographs of Leucaena leucocephala seeds to their physiological potential by means of multivariate analysis. To do so, seeds from five lots collected from parent trees from the region of Viçosa, MG, Brazil, were used. The study was carried out through analysis of radiographic images of seeds, from which the percentage of damaged seeds (predation and fungi), and measurements of area, perimeter, circularity, relative density, and integrated density of the seeds were obtained. After the X-ray test, the seeds were tested for germination in order to assess variables related to seed physiological quality. Multivariate statistics were applied to the data generated, with use of principal component analysis (PCA). X-ray testing allowed visualization of details of the internal structure of seeds and differences regarding density of seed tissues. Semi-automated analysis of radiographic images of Leucaena leucocephala seeds provides information on seed physical characteristics and generates parameters related to seed physiological quality in a simple, fast, and inexpensive manner.

The use of new methodological approaches and inclusion of non-destructive evaluations in determining the quality of forest seeds has proven to be of great importance for the development of forest production. The aim of this study was to evaluate the effectiveness of the use of a semi-automated tool for measurement of digital images obtained by the X-ray test in seed lots of Leucaena leucocephala and their relationship to seed physiological quality. Seeds were collected from five mother trees in Viçosa, MG. The study was performed through analysis of radiographic images of the seeds. It was determined the percentage of damaged seeds (predation and fungi) and measured: the area, perimeter, circularity, relative density, and integrated density of the seeds. After the X-ray test, a germination test was performed on the seeds, from which ten variables related to seed physiological quality were extracted, including a vigor index. The use of semi-automated measurement tools associated with the X-ray test was effective for evaluating the internal morphology of Leucaena leucocephala seeds, and the variables determined are related to seed physiological quality.

The definition of methodologies that allow evaluating the physiological potential of chickpea seeds is important to ensure the commercialization of lots with high performance. Thus, this research aimed to determine the most suitable conditions for conducting the electrical conductivity test in chickpea seeds to classify lots according to vigor level. Therefore, seeds from five lots of cultivar BRS Aleppo and four lots of cultivar Cícero were subjected to tests to characterize their initial quality and the results were compared with those obtained in the electrical conductivity test. To assess electrical conductivity, five soaking periods (2, 4, 8, 12, and 24 hours) were combined with four volumes of water (75, 100, 150, and 250 mL) at 25 °C temperature. The results show that the electrical conductivity test is efficient in evaluating the physiological potential of chickpea seeds, providing information equivalent to other vigor tests. For the electrical conductivity test, it is recommended to use 50 seeds soaked in 150 mL of water, for 24 h, at 25 °C.

-The exudate coloring test has been promising in order to quickly evaluate the quality of coffee seeds. The objective of the research was to adjust the coloring exudate test for coffee seeds and to evaluate the influence of the water content of seeds and of the imbibition period on the test results. Seeds from five lots of 'Catuaí 44' were used, with the following water contents: 30%, 20% and 12%. For the exudate coloring test, the parchment and silver skin (spermoderm) from the seeds were removed. Then, the seeds were distributed on a paper towel, moistened with water, and kept in a germinator at 25 °C for 24, 48, 72, 96 and 120 h. Four classes of coloring intensity were established: absence of color (A), light (L), medium (M) and strong (S) intensities, assigning the values 0, 3, 5 and 10 for each class, respectively. The Viability Index (VI) was calculated by the equation VI=100-(0xA)-(3xL)-(5xM)-(10xS). The exudate coloring test may be recommended to estimate the viability of coffee seeds, providing results correlated to the germination test. The best results were obtained for the seeds with 12% moisture content imbibed for 72, 96 and 120 h and seeds with 30% moisture content after 72 and 120 h of imbibition.

Seeds vigor can influence seed performance under stress conditions. The objectives of this study were to evaluate the effect of water and thermal stress on germination and performance of melon seedlings, and to verify if germination under stress conditions is an efficient parameter to evaluate the vigor of these seeds. Four lots of ‘Golden Mine’ melon had their initial quality characterized by germination, first count, accelerated aging and seedling emergence tests. Germination under water stress was performed on a paper moistened with PEG 6000 solution at 0.06, -0.3, -0.6 and -0.9 MPa. The percentage and speed of germination, length and dry mass of the seedlings were evaluated. For the thermal stress experiment, cold test and germination at sub- (15 ºC) and supra-optimal (35 ºC) temperatures were performed, as well as at the ideal temperature (25 ºC). The germination of melon seeds under water stress induced by PEG 6000 at -0.3 and -0.6 MPa is an efficient method to detect differences in the physiological potential of lots of melon seeds, but these differences disappear under severe water stress (-0.9 MPa). Germination under sub-optimal temperatures also allows to identify differences in seeds performance and to classify them according to the vigor level.

The tetrazolium test has been recommended for evaluating the viability of seeds with slow and ununiform germination, especially agroforestry species. The aim of this study was to propose a methodology to evaluate the viability of J. curcas L. seeds using the tetrazolium test and to generate visual aids to support the interpretation of the test. In the first trial, methods of seed preparation and staining were evaluated. The most promising methodologies were used to conduct the second test, which consisted of the evaluation of different concentrations (0.10 and 0.25%) and times (2 and 3 h) of immersion of the seeds in the tetrazolium solution, using five lots. The seeds were analyzed individually and classified as viable or non-viable. At the same time, germination, first count, emergence and seedling emergence speed index tests were conducted. The tetrazolium test is efficient for evaluating the viability of seeds of J. curcas L. providing results correlated with germination and seedling emergence. Pre-soaked seeds should have their integument removed and then sectioned longitudinally and medially lengthwise for immersion in 0.10% solution of 2,3,5-triphenyl chloride tetrazolium for three hours at 35 °C.

The chickpea crop has been expanding in Brazil and, thus, the demand for high quality seeds along with it. The aim of this study was to adapt the methodology for evaluation of chickpea seed vigor by the accelerated aging test and to analyze whether antioxidant enzyme activity is related to the physiological potential of these seeds. Seeds from five seed lots of the cv. BRS Aleppo and from four seed lots of the cv. Cícero were initially tested to characterize their physiological potential. The accelerated aging test was conducted by the traditional method (100% RH) and with a saturated NaCl solution (76% RH), both at 41 °C, for 24, 36, 48, and 72 h. The activity of the SOD, CAT, and APX enzymes were also determined. The accelerated aging test using 41 °C/48 h with a saturated NaCl solution is recommended for assessment of chickpea seed vigor. The activity of CAT and APX enzymes may be related to the physiological potential of these seeds, but this is not the case with SOD.

Computerized seedling analysis is a promising tool for assessing seed vigor, providing reliable and less subjective results. The aim of this study was to define a method for evaluating the vigor of chickpea seeds through computerized image analysis, using the Seedling Analysis System (Sistema de Análise de Plântula - SAPL®) as a basis. Two chickpea cultivars were evaluated, consisting of five seed lots of cv. BRS Aleppo and four seed lots of cv. Cícero. Test were performed on the seeds of each cultivar for initial characterization of the physiological potential of the lots, and the results were compared with the determinations made via SAPL®. The results showed high correlations between the variables obtained from computerized analysis and from traditional vigor tests, especially for the close relationship between the cold test and low temperature germination test with the corrected vigor index (r > 0.9) evaluated on the fourth day after the beginning of the test. The total length of seedlings, length of the primary root, and growth and corrected vigor indices obtained through computerized analysis of seedlings on the 4th day after sowing allowed separation of the lots regarding vigor. Computerized analysis of seedlings using SAPL® is effective in determining the vigor of chickpea seed lots.