The process of germination in six different wheat cultivars was monitored using NIR spectroscopy and the Rapid Visco Analyser (RVA) method. Near-infrared spectra provided insight into both chemical and physical changes that occur in the seed, in particular mobilization processes involving carbohydrates. RVA curves also contain physical and chemical information and can be interpreted as physicochemical spectra. The process of germination was followed sensitively through the RVA curves and some rheological parameters (peak viscosity, trough, breakdown, final viscosity, and setback) were highly correlated (R = 0.95-0.98) with predicted values calculated from NIR spectra. Viscosity data calculated from RVA curves collected at 200-480 sec showed the most characteristic changes during the early heat treatment stage of the pasting procedure. Strong intercorrelations were found between viscosity data and NIR spectra from the beginning of the swelling and gelatinization processes in germinating seed. The NIR and RVA methods were sensitive tools for the rapid investigation of the germination process, which is important both from a physiological and technological point of view.

Development of small white flower morningglory seeds were studied in the field and laboratory. Seeds reached their physical maturity and field maturity stage at day 21 and day 27 to 28 after blooming, respectively. Seeds collected at day 21 after blooming had 96 percent germination. Hardseeds developed at day 24 to 25 after blooming and germination decreased to 20 percent or less when harvested 25 days or more after blooming. The germination of seeds collected in the field at field maturity in the dry season was less than the seeds collected in the rainy season. Storage of hardseeds under room temperature for 66 weeks did not affect germination, but acid scarification increased germination. Storage of acid-scarified hardseeds under room temperature decreased their germination and coefficient of velocity but increased the percentage of non-viable seeds. At week 35 after storage, 48 percent of acid-scarified hardseeds seeds could germinate. The germination percentage of unscarified hardseeds stored in soil was reduced when increasing the period of storage. At week 77 after placing hardseeds in soil, 22 percent of seeds could germinate after acid scarification.

High temperature stress during seed filling in controlled environments reduces soybean [Glycine max (L.) Merrill] seed germination and vigor, but the effect of high temperature in the field has not been determined. Seeds of two soybean cultivars (Hutcheson, maturity group [MG] V, and DP4690, MG IV) were produced in the field in Kentucky, Mississippi, Arkansas, and Texas in 2000 to 2002. Air temperature during seed filling was monitored and brown (mature) pods were harvested, hand threshed, and all shriveled and abnormal seeds were removed before determining standard germination and vigor (accelerated-aging germination). Mean maximum temperatures during seed filling (growth stage R5 to R7) ranged from 24.0 (Kentucky) to 37.6°C (Texas). When seed lots infected with Phomopsis longicolla (Hobbs) were removed from the analysis, standard germination and accelerated-aging germination (AA) decreased as mean maximum temperature during seed filling increased, but the decrease was significant (P = 0.05) only for Hutcheson. Standard germination of Hutcheson declined linearly (r ² = 0.49) from near 100% at 24°C to 85% at 36°C, while the decrease in AA was curvilinear (R ² = 0.86) and germination reached 11% at 36°C. Seeds of Hutcheson were more sensitive to high temperature than seeds of DP4690 and seed vigor (AA) was much more sensitive to high-temperature stress than was standard germination. Our findings support the results of experiments in controlled environments by demonstrating that high temperature during seed filling in the field, without seed infection with P. longicolla or physical injury, reduced soybean seed germination and vigor.

High temperature stress during seed filling in controlled environments reduces soybean [Glycine max (L.) Merrill] seed germination and vigor, but the effect of high temperature in the field has not been determined. Seeds of two soybean cultivars (Hutcheson, maturity group [MG] V, and DP4690, MG IV) were produced in the field in Kentucky, Mississippi, Arkansas, and Texas in 2000 to 2002. Air temperature during seed filling was monitored and brown (mature) pods were harvested, hand threshed, and all shriveled and abnormal seeds were removed before determining standard germination and vigor (accelerated-aging germination). Mean maximum temperatures during seed filling (growth stage R5 to R7) ranged from 24.0 (Kentucky) to 37.6 degrees C (Texas). When seed lots infected with Phomopsis longicolla (Hobbs) were removed from the analysis, standard germination and accelerated-aging germination (AA) decreased as mean maximum temperature during seed filling increased, but the decrease was significant (P = 0.05) only for Hutcheson. Standard germination of Hutcheson declined linearly (r2 = 0.49) from near 100% at 24 degrees C to 85% at 36 degrees C, while the decrease in AA was curvilinear (R2 = 0.86) and germination reached 11% at 36 degrees C. Seeds of Hutcheson were more sensitive to high temperature than seeds of DP4690 and seed vigor (AA) was much more sensitive to high-temperature stress than was standard germination. Our findings support the results of experiments in controlled environments by demonstrating that high temperature during seed filling in the field, without seed infection with P. longicolla or physical injury, reduced soybean seed germination and vigor.

Mexican palo-verde is a serious woody weed in tropical parts of the world. Like many such leguminous species, it has relatively large seeds with hard-seeded (physical) dormancy. It therefore has the potential for long-lived seed banks that are difficult to manage. The physiology of hard-seeded dormancy is still relatively poorly understood but has important implications for weed management. We propose that wet heat is a potentially important dormancy release mechanism for summer rainfall tropical regions. We described the relationships between wet heat and dormancy release (in water; three seed sources) and germination (near saturation; single seed source) by testing seeds at constant temperatures between 10 and 60 C. The logistic transformation of the temperature––dormancy relationship was best described by a quadratic equation below a threshold of ∼∼ 33.6 C and a linear equation above that threshold. The relationship was the same for all seed sources other than a phase shift of up to 6.6 C, which is likely to be of biological significance. Germination occurred between 15 and 40 C and was limited by cold stress at ≤≤ 20 C and heat stress > 35 C. The sensitivity of dormancy to naturally encountered temperature ranges suggests that wet heat is an important dormancy release mechanism and one that can be exploited when developing management strategies for invasive populations.Nomenclature: Mexican palo-verde, Parkinsonia aculeata L. PAKAC.

We investigated the changes in the properties of water when exposed to sunlight for 40 days. We hypothesize and prove that solar irradiation to water entraps electromagnetic radiation as potential energy, which becomes kinetic energy in various systems. It is postulated that photochemically-induced energy transfers, associated with individual spectral emission of visible spectrum of solar light, exert diverse influences on biological systems. Bottles of distilled water, individually wrapped in spectral-colored cellophane were exposed to sunlight and compared to an unwrapped bottle to determine chemical and physical changes as well as modifications of biological properties. Each bottle of water was named according to the color of cellophane paper with letter E (stands for exposed) as a prefix with (E-violet, E-indigo, E-blue, E-green, E-yellow, E-orange, and Ered). E-control (without wrap) was exposed to polychromatic sunlight. This study addresses two main issues viz., the chemical and physical changes in E-water and its effect on biological activities. Chemical and physical composition analysis using inductively coupled plasma atomic emission spectrometry: physical conductance by a Wheatstone Bridge type conductivity meter: osmolarity by a vapor pressure osmometer: and, salt solubility profile of 10% sodium bicarbonate were determined. Furthermore, testing the effect of E-waters on human lymphocyte proliferation, mosquito larvae hatching and seed germination determined the functional role of solar radiation through specific spectrum/s of visible light on various biological processes. We found that water exposed to visible spectral emissions of sunlight had an altered elemental composition, electrical conductance, osmolarity and salt-solubility, as well as differences in bio-modulatory effects. A gradual increase in leaching of Boron from Eviolet to E-red was noted. E-indigo showed maximal increase in electrical conductance and maximal salt solubility of sodium bicarbonate. E-blue inhibited phyto-hemagglutinin-induced immune cell proliferation and mosquito larvae hatching. E-orange stimulated root elongation in seed germination. We conclude that 40-day exposure of water to specific solar spectrum changes chemical and physical properties and influences on biological activity.

We examined the relative roles of biotic resistance and abiotic factors in controlling the establishment and early survival of an invasive marine grass, Spartina anglica, in the Pacific Northwest. S. anglica can invade diverse estuarine habitats, including established salt marshes, mudflats, and cobble beaches; these vary in native species assemblages and in abiotic conditions, especially sediment salinity, water content, and composition. In four habitat types in northern Puget Sound, we conducted a seed addition experiment to quantify germination and early growth. In vegetated habitats we also manipulated plant neighbors. Seed germination and early growth varied with habitat and zone, but physical factors played a more important role than species interactions. Seedlings in low‐salinity marshes and mudflats grew almost 10 times larger than those in coarse‐grained or high‐salinity habitats. Patterns of seedling persistence among habitats matched those of natural seedling abundances and mirrored the degree of invasion in different habitat types in the region. The lack of biotic resistance may be due to the stressful nature of saline systems or the lack of species that can compete with or consume the invader. In such systems, managers should focus on how physical vulnerabilities of the habitat can provide invasion “windows of opportunity.”

Pepper transplants were grown in trays using 6 different growing media. Trays were filled in a loose and in a compact manner with the 5 different peats and coconut coir. Measurements were made for the most important physical parameters of each single medium studying their effect on transplant development. Results indicated that compaction had had a beneficial effect on the germination of the transplants and on the rate of their development.

A viticultura possui um relevante papel econômico, social e cultural na fruticultura nacional e mundial. No Brasil, a atividade apresentou uma considerável expansão nas últimas décadas, tanto pelo aumento da área cultivada nas regiões tradicionais, como pelo surgimento de novos pólos de produção. Atualmente, a grande maioria das cultivares comerciais utilizadas no Brasil é oriunda de zonas temperadas. Por conta disso, nos programas de melhoramento da videira busca-se a obtenção de cultivares adaptados às diferentes regiões do país, que apresentem alta produtividade e resistência às principais doenças fúngicas, bem como qualidade compatível com as exigências do mercado. Dentro desse processo de melhoramento da cultura, o baixo índice e o longo período requerido para a germinação das sementes são os principais gargalos. A baixa germinação dessas sementes é atribuída à dormência, que segundo a literatura é causada pela ação de inibidores químicos presentes nas sementes e/ou fruto. Em geral, os métodos utilizados atualmente na quebra dessa dormência são o uso do ácido giberélico e da estratificação. No entanto, esses métodos proporcionam porcentagens de germinação que raramente ultrapassam o valor de 50%, além de demandar um considerável período de tempo para a germinação. Os objetivos gerais desse trabalho foram avaliar tratamentos físicos e químicos aplicados às sementes, bem como o efeito das condições in vitro e ex vitro sobre a porcentagem e velocidade de germinação dessas sementes.Os tratamentos físicos aplicados às sementes consistiram em cortes nas regiões mediana e da micrópila. A imersão das sementes em soluções de ácido giberélico com diferentes concentrações por 24 horas foi o tratamento químico utilizado. No ambiente in vitro as sementes foram inoculadas em tubos de ensaio contendo meio MS e na condição ex vitro utilizou-se o substrato Plantmax®, esterilizado e distribuído em caixas de Gerbox de dimensões 63 x 98 mm. Os tratamentos físicos foram fundamentais para a porcentagem e velocidade de germinação das sementes dentro do período de avaliação do experimento. O GA3 teve efeito significativo na germinação das sementes das duas espécies utilizadas, Vitis vinifera L. cv. ‘Itália’ e Vitis x Labruscana L.H. Bailey cv. ‘Niágara Rosada’, entretanto, somente a velocidade de germinação do cv.’Itália’ foi aumentada com o uso de ácido giberélico. Observou-se também que o ambiente in vitro não é imprescindível à germinação das sementes e que apesar de apresentar menor porcentagem, a germinação ocorreu normalmente em ambiente ex vitro. | Viticulture plays a very important economic, social and cultural role in the national and world horticulture. In Brazil, the activity has grown considerably in the last decades, increasing the area cultivated in traditional regions, as well as bringing about new production regions. Recently, most commercial cultivars used in Brazil come from temperate regions. For these reasons, grapevine breeding programs aim for obtaining cultivars adapted to the different regions of the Country, which have high productivity and resistance to the main fungal diseases, as well as meeting the quality market demands. Within the process of grape breeding, the low rate and long period for seed germination are the main bottlenecks. Low germination, according to the literature, is attributed to dormancy, which is caused by the action of chemical inhibitors present in the seeds and/or fruit. In general, the current methods used for overcoming seed dormancy are gibberellic acid application and stratification. However, these methods provide germination rates rarely surpassing 50%, and demand a long period of time for germination. The objectives of this work were to evaluate physical and chemical treatments applied to the seeds, as well as the effect of in vitro and ex vitro conditions on the rate and speed of germination of these seeds. Physical treatments applied to seeds were done by cuts on the middle of the seeds and at the micropyle regions. Chemical treatment used was immersion of the seeds in gibberellic acid solution with different concentrations during 24 hours. Seeds treated were innoculated in vitro in MS medium, and at ex vitro condition in sterilized Plantmax® substratum distributed in Gerbox boxes with dimensions of 63 x 98 mm. The physical treatments applied were fundamental for the rate and speed of seed germination within the period of evaluation of the experiment. GA3 had significant effect on seed germination for both species, Vitis vinifera L. cv. 'Italia' and Vitis x Labruscana L.H. Bailey cv. ‘Niagara Rosada'. However, the speed of germination of cv.' Italia' was the only increased with the gibberellic acid application. It was also verified that in vitro environment is not essential to germination, and in spite of presenting lower rate and speed, the germination occurred normally at ex vitro environment. | Conselho Nacional de Desenvolvimento Científico e Tecnológico

Three Korean soybean varieties - Shinpaldal-2, Seomoktae and Seoritae - were investigated for changes in their physical properties and the amount of functional components (i.e. isoflavones and oligosaccharides), during germination. Soybeans were germinated at 20℃ for 96 hr in complete darkness. The dry weights of cotyledone, hypocotyl, seed coat, and hilum of Seoritae were heavier than those of other varieties. The dry weights of the three bean varieties decreased steadily in spite of root growth.