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The identification of pod- and seed-related traits of soybean genotypes and their interaction with water uptake can be applied in breeding programs with a view to establishing cultivars developed for the production and maintenance of high-quality seeds. The objective was to evaluate the water uptake of pods and seeds of soybean cultivars with different lignin contents after different soaking periods. The experimental was arranged in a completely randomized, 7×10 factorial design, with four replications. The factors consisted of seven soybean cultivars and 10 soaking periods (1, 2, 3, 4, 5, 6, 7, 8, 24, 48 hours). The pods and seeds were grown in a greenhouse and harvested at the phenological growth stage R8 (at full maturation, when 95% of the pods had mature color). The following traits were evaluated: lignin content in pod and seed coat, moisture content, and rate of water uptake of pods and seeds. Soybean cultivars with pods with high lignin contents have a lower rate of water uptake. The lignin contents of the seed coats, within the chosen limits, did not affect the seed water uptake. [ABSTRACT FROM AUTHOR]

To maintain the physical, physiological and sanitary qualities of soybean seeds during storage, efficient control of pests must be considered. Fumigation is a technique used to eliminate pests that infest stored seeds, but there is no information on possible toxic effects on the seed and the microorganisms in the seeds fumigated several times during storage. An experiment was conducted to ascertain its effect on germination, viability, and vigor (tetrazolium, accelerated aging, and seedling length tests) and on the microorganisms associated with the soybean seeds. The study was conducted on soybean seeds which were exposed to three phosphine fumigations over the period of 210 days of storage in a completely randomized statistical design. The treatments were three concentrations of phosphine (PH3.m-3) at 1.0, 2.0 and 3.0 g.m-3 and the control without application of phosphine, applied three times on the same group of the seeds throughout the storage period. The fumigation chambers were made of plastic sheet impermeable to phosphine gas. Seed fumigation did not modify the physiological performance of the soybean seeds. It also did not affect the viability of the fungi and bacteria in the seeds. [ABSTRACT FROM AUTHOR]

The production of high quality seeds is linked to a good quality control system. In this system, the tetrazolium test plays an important role in the evaluation of the seed physiological quality, not only due to its relative quickness, but also because of the amount of information that the test presents, such as the indexes of viability and vigor, in addition to providing the diagnosis of possible seed quality problems, such as mechanical damage, insect damage, pre-harvest weathering and deterioration during storage. The development of the test had its beginnings at the end of the 19th century, with great evolution in its concepts and methods in the 20th century. For that, there was the dedication of dozens of professionals in several countries, such as Germany, Japan, Russia, Serbia (former Yugoslavia), United States, Argentina and Brazil. The test indirectly measures the respiration processes that occur in the mitochondria of the cells that make up the tissues of the seeds. The reducing reaction of the solution of the tetrazolium salt under the action of dehydrogenase enzymes results in triphenylformazan, which presents a red carmin coloration. By the interpretation of the resulting staining patterns, seed viability, vigor and the main problems affecting seed quality are determined. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Seed Science is the property of Associacao Brasileira de Tecnologia de Sementes and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Seed Science is the property of Associacao Brasileira de Tecnologia de Sementes and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Seed Science is the property of Associacao Brasileira de Tecnologia de Sementes and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Seed Science is the property of Associacao Brasileira de Tecnologia de Sementes and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Seed Science is the property of Associacao Brasileira de Tecnologia de Sementes and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Informativo Abrates is the property of Associacao Brasileira de Tecnologia de Sementes and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of this study was to evaluate the influence of pod wall permeability on the physiological quality of soybean seed. The cultivars studied were Sant'Ana, FT-2, FT-10, Bossier, Davis and the breeding line F 84-7-30, with a black seed coat. Pods were collected from plants at the R4, R5, R6, R7 and R8 development stages, which composed the treatments in regard to time of harvest. The parameters of permeability and the lignin content of the pods and the seeds within the pods were evaluated. The seeds were collected just after full maturity (R8), and the following tests were performed: germination, electrical conductivity, and tetrazolium, which determined seed viability and vigor. A randomized complete block design in a split-plot in time arrangement was used, with four replications per treatment. The soybean genotypes (six) composed the plots, and the split-plots consisted of the development stages (R4, R5, R6, R7 and R8). In seed evaluation, the same design was used, reducing the number of treatments to three in the split-plots (R6, R7 and R8). Pod permeability varied with the genotype and stage of development; this affected seed vigor, but not the viability of newly-harvested seeds. The pod lignin content did not show any influence on pod permeability. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Seed Science is the property of Associacao Brasileira de Tecnologia de Sementes and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The assessment of the germination test in wheat seeds varies from 4 to 15 days, because the species normally presents dormancy in freshly harvested seeds. The tetrazolium test can characterize seed viability in less than 24 hours including lots with dormancy seeds. The objective of this study was to develop a practical and efficient procedure for evaluating the viability of wheat seeds using the tetrazolium test. Five seed lots of the BRS 208 cultivar were used, where the following were tested: a) pre-conditioning between moist paper towels or direct immersion in water for 18 hours, at 20 °C; b) longitudinal section of the embryo and the endosperm; c) coloration on paper or by immersion for 2 and 3 hours, at 30 and 40 °C; and d) concentrations of tetrazolium solution at 0.075%, 0.1%, 0.5% and 1.0%. The tetrazolium test may be efficiently used to evaluate wheat seed viability by pre-conditioning the seeds between paper towels (18 hours, at 20 °C) and adopting the following combinations of preparation and coloration: coloration of both halves of the seed on paper (2 hours, at 30 °C), in a 1.0% tetrazolium solution; or coloration of one half of the seed by immersion (3 hours, at 30 °C), in a 0.1% tetrazolium solution; or coloration of one half of the seed by immersion (2 hours, at 40 °C), in a 0.075% tetrazolium solution. This latter procedure is recommended for identifying and discarding lots with lower viability. [ABSTRACT FROM AUTHOR]

Fumigation is a technique employed to eliminate insect pests in stored seeds by using gas. The aim of the experiment was to evaluate the effect of the gas phosphine on germination and on vigor (accelerated aging and seedling length) of soybean seeds. Soybean seeds of two cultivars with two vigor levels were used. Each treatment was replicated four times and each experimental unit consisted of two kilograms of seeds, which were placed in individual 1 m3 gas-tight capacity chambers with phosphine. The concentrations used were 1.0; 2.0 and 3.0 g PH3.m-3, achieved by applying 3.0; 6.0 and 9.0 g of Fertox® commercial formulation. During seven days, the phosphine gas concentration within each chamber was monitored using the Silochek® gas meter. After this period, the chambers were opened, the seeds were removed and the quality analyses were performed. Throughout the experiment, PH3 concentrations in the chambers remained at the concentrations required for the elimination of all life stages of insect pests of stored seed. Even in the lowest dosage, the gas concentration remained above 400 ppm that is considered the minimum concentration for eliminating insect pests. No detrimental effects were detected on the physiological quality of the fumigated seeds. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Seed Science is the property of Associacao Brasileira de Tecnologia de Sementes and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effect of constant temperature on the germination rate and percentage of two cotton seed lots was determined using a thermogradient plate. A gradient of 10 °C to 40 °C was established across the plate so that temperatures changed 2 °C for each 5 cm increment in length, resulting in sixteen different temperature treatments. The optimal temperature zone for germination was 28 °C to 30 °C. As temperature decreased from the optimal zone, the rate of germination also decreased but germination percentages during the 10-day period were significantly lower only below 20 °C. As temperature increased above the optimal zone, the rate of germination decreased and the percentage of germination sharply decreased above 32 °C - 34 °C. As expected, high quality cotton seed performed better than medium quality seed for a low temperature range (16 °C to 22 °C), but the most intriguing results were observed for the high temperatures range (36 °C to38 °C). The germination of medium quality cotton seed was consistently higher than for high quality seed, especially at 38 °C after the second day of evaluation. This response has not been reported in the literature and further research is needed to better understand the germination physiology of cotton seed at high temperatures. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Sementes is the property of Associacao Brasileira de Tecnologia de Sementes and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)