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Climate change models predict temperature increases, which may affect germination, an important stage in the recruitment of individuals in agroecosystems. Therefore, it is crucial to conduct research on how temperature will impact the germination of multipurpose native species. Leucaena diversifolia (Schltdl.) Benth. is native to America and is commonly cultivated around the world due to having a high protein content in seeds, and their trees are used in agrosilvopastoral systems because they fix nitrogen and provide shade and cattle feed. However, climate change affects the critical phases of its life cycle and influences its growth, reproduction, phenology, and distribution. To assess the germination performance of Leucaena diversifolia under different temperatures throughout thermal times, we estimated germination variables and determined cardinal temperatures and thermal time; we also analysed germination and potential distribution under two climate change scenarios. We found significant variations in seed germination (78–98%) and differences in cardinal temperatures (Tb = 5.17 and 7.6 °C, To = 29.42 and 29.54 °C, and Tc = 39.45 and 39.76 °C). On the other hand, the sub-optimal and supra-optimal temperature values showed little differences: 51.34 and 55.57 °Cd. The models used showed variations in germination time for the analysed scenarios and the potential distribution. We confirm that the populations and distribution of L. diversifolia will be altered due to climate changes, but the species retains the ability to germinate under warmer conditions. [ABSTRACT FROM AUTHOR]

Cuphea pulchra Moric. is a species native to the Cerrado and Caatinga biomes that grows in environments with high temperatures and low rainfall and can be adapted as an ornamental plant for pots. Tests were carried out on C. pulchra seeds, as well as the cultivation of plants from both seeds and cuttings in a greenhouse. Seeds at different stages of maturity (green, almost ripe, and mature) were placed on agar and paper for germination tests. The cultivated plants were pruned as necessary. Two cutting tests were carried out according to the age of the donor plant. The flowering period was monitored. Germination was successful with the almost ripe seeds. Drastic pruning was able to produce compact plants in pots. Cutting tests had greater sprouting with younger donor plants. Cuphea pulchra stood out in terms of the length of the flowering period, which lasted up to ten months. Greenhouse cultivation produced viable plants for the ornamental plant market. [ABSTRACT FROM AUTHOR]

The seed industry plays a crucial role in global food production but it faces a persistent challenge in ensuring the health and quality of seeds, particularly those of tomato and pepper seeds, which represent key seed commodities on the global market. Seeds can serve as potential pathways for the introduction and dissemination of seed-borne bacteria, which may have devastating effects on crop yield, farmers' remunerability, and food security. Therefore, fungicides and other antimicrobial compounds are extensively used to disinfect the seeds, thus increasing the input of chemicals in the agri-environment. In this review, we address aspects that connect disease epidemiology with seed infection and health, including seed contamination, endophytic colonization, and seed-borne infections. We focused on the main bacterial diseases affecting tomato and pepper seeds by discussing their official seed testing methods as requirements supporting a smooth seed trade. Moreover, we present a survey on the past and recent innovations for seed treatments, focusing on sustainable disinfection methods. Therefore, this review will be a short but indispensable guide for seed technologists and pathologists involved in the production of high-quality seeds, providing indications and suggestions to contrast seed-borne pathogen dissemination and avoid international controversies and complaints by phytosanitary authorities, extension services, and farmers. [ABSTRACT FROM AUTHOR]

The crises of biodiversity loss, climate change and food security are challenges faced by the conservation and agriculture sectors.We outline, via presentations from the Australasian Seed Science Conference, how seed science is addressing these challenges. Research is focused on practical solutions for seed bank management, seed use and biodiversity conservation. Emerging trends include understanding the role of seed microbiota on plant performance and the roles of seeds in society and culture. [ABSTRACT FROM AUTHOR]

Background and Aims Seed germination is strongly influenced by environmental temperatures. With global temperatures predicted to rise, the timing of germination for thousands of plant species could change, leading to potential decreases in fitness and ecosystem-wide impacts. The thermogradient plate (TGP) is a powerful but underutilized research tool that tests germination under a broad range of constant and alternating temperatures, giving researchers the ability to predict germination characteristics using current and future climates. Previously, limitations surrounding experimental design and data analysis methods have discouraged its use in seed biology research. Methods Here, we have developed a freely available R script that uses TGP data to analyse seed germination responses to temperature. We illustrate this analysis framework using three example species: Wollemia nobilis , Callitris baileyi and Alectryon subdentatus. The script generates >40 germination indices including germination rates and final germination across each cell of the TGP. These indices are then used to populate generalized additive models and predict germination under current and future monthly maximum and minimum temperatures anywhere on the globe. Key Results In our study species, modelled data were highly correlated with observed data, allowing confident predictions of monthly germination patterns for current and future climates. Wollemia nobilis germinated across a broad range of temperatures and was relatively unaffected by predicted future temperatures. In contrast, C. baileyi and A. subdentatus showed strong seasonal temperature responses, and the timing for peak germination was predicted to shift seasonally under future temperatures. Conclusions Our experimental workflow is a leap forward in the analysis of TGP experiments, increasing its many potential benefits, thereby improving research predictions and providing substantial information to inform management and conservation of plant species globally. [ABSTRACT FROM AUTHOR]

Most of the quality indicators regulated by the standard for seed potato certification are determined by the subjective component, that is, the competence of the personnel. However, the regulatory framework does not establish criteria for assessing competence, which poses uncontrolled risks in the laboratory. The purpose of the study is to develop and investigate the methodology for assessing the competence of laboratory personnel involved in the testing of seed potatoes and determine the extent of application of the methodology. The methods of probability theory and mathematical statistics are used for the tasks of selection and research of statistical criteria that correspond to the law of distribution of the obtained data and provide the necessary reliability for the available sample volumes. The statistics and the method of determining the threshold value, which mathematically describes the decision-making on competence, are provided for the binomial distribution law. The properties of the proposed statistical method for assessing the competence of personnel in terms of finding the maximum differences in the results of the analysis, at which the personnel are recognised as competent, are investigated. The study demonstrates the dependence of the method capacity on the data volume. It is determined that to obtain a confidence probability of 0.95 for quality indicators, the content of which in the average sample according to the technical conditions is minimal, the sample size should be 600-1000 tubers. At the same time, up to 100 tubers are sufficient for indicators whose content is under 5%. The method proposed by the authors showed that the average sample of 250 tubers recommended by the standard is entirely justified in terms of attracting resources during certification but must be adjusted during competence monitoring in a testing laboratory that confirms its competence by the requirements of DSTU ISO IEC 17025:2019. The findings presented can be used by the personnel in the seed testing laboratories as a measure to minimise the risks caused by the impact of personnel incompetence . [ABSTRACT FROM AUTHOR]

Optimal oil palm (Elaeis guineensis) crop yields rely on the purity of the tenera fruit form. The high yielding hybrid tenera fruit form is the consequence of heterozygosity for one of nine genetic variants within the SHELL gene. High-throughput genotyping allows cost-efficient screening prior to planting to decrease unintentional non-tenera palm cultivation. We present a paradigm for dramatically reducing non-tenera cultivation by SHELL genotyping a ~ 10% sampling of seeds per seed production fruit bunch. Identification and seed supply chain removal of bunches above a predetermined non-tenera threshold represent a new paradigm for applying SHELL genetic testing in the industry. In a demonstration involving 121,896 embryos from 1304 independent dura x pisifera controlled crosses from two independent seed production units, we found that 38.4% of bunches achieved a 100% pure tenera prediction rate. The remaining bunches (61.6%) had predicted non-tenera contamination ranging from 1.0 to 89.6%, with an overall average of 3.32% seeds per bunch. SHELL genotyping of expected tenera embryos identified rare aneuploid embryos, confirmed by whole genome sequencing-based heterozygosity and copy number analyses. [ABSTRACT FROM AUTHOR]

The Australian native seed sector is critical for undertaking ecological restoration but faces serious challenges from interacting factors, including native vegetation loss and habitat fragmentation, low funding levels, and climate change impacts. The Australian Native Seed Survey was conducted in 2016–2017 to better understand sector structure, practitioner perceptions, and practice. It found that most native seed is collected from small and fragmented tenures and from geographic ranges that greatly exceed "local provenance"; that the diversity of species available for restoration is typically low; that native seed is seldom quality tested; and that most annual seed collections (wild or production) are small in volume suggesting overall seed yields are modest in quantity and not sufficient to support large‐scale restoration. Together, survey findings raise serious concerns about the ability of the sector, as currently constituted and resourced, to meet projected future increases in the demand for seed or for achieving the effectiveness and efficiency required to meet UN‐Decade type ecological restoration outcomes. Central to recommendations for sector improvement are the following focus areas: maturing the native seed sector; sustainability; seed production; licensing; seed testing and tracking; and research. [ABSTRACT FROM AUTHOR]

Tomato brown rugose fruit virus (ToBRFV) represents an emerging viral threat to the productivity of tomato and pepper protected cultivation worldwide. This virus has got the status of quarantine organism in the European Union (EU) countries. In particular, tomato and pepper seeds will need to be free of ToBRFV before entering the EU and before coming on the market. Thus, lab tests are needed. Here, we develop and validate a one-step reverse transcription LAMP platform for the detection of ToBRFV in tomato and pepper leaves, by real-time assay [reverse transcription loop-mediated isothermal amplification (RT-LAMP)] and visual screening (visual RT-LAMP). Moreover, these methods can also be applied successfully for ToBRFV detection in tomato and pepper seeds. The diagnostic specificity and sensitivity of both RT-LAMP and visual RT-LAMP are both 100%, with a detection limit of nearly 2.25 fg/μl, showing the same sensitivity as RT-qPCR Sybr Green, but 100 times more sensitive than end-point RT-PCR diagnostic methods. In artificially contaminated seeds, the proposed LAMP assays detected ToBRFV in 100% of contaminated seed lots, for up to 0.025–0.033% contamination rates in tomato and pepper, respectively. Our results demonstrate that the proposed LAMP assays are simple, inexpensive, and sensitive enough for the detection of ToBRFV, especially in seed health testing. Hence, these methods have great potential application in the routine detection of ToBRFV, both in seeds and plants, reducing the risk of epidemics. [ABSTRACT FROM AUTHOR]

From 50 to 90% of wild plant species worldwide produce seeds that are dormant upon maturity, with specific dormancy traits driven by species' occurrence geography, growth form, and genetic factors. While dormancy is a beneficial adaptation for intact natural systems, it can limit plant recruitment in restoration scenarios because seeds may take several seasons to lose dormancy and consequently show low or erratic germination. During this time, seed predation, weed competition, soil erosion, and seed viability loss can lead to plant re‐establishment failure. Understanding and considering seed dormancy and germination traits in restoration planning are thus critical to ensuring effective seed management and seed use efficiency. There are five known dormancy classes (physiological, physical, combinational, morphological, and morphophysiological), each requiring specific cues to alleviate dormancy and enable germination. The dormancy status of a seed can be determined through a series of simple steps that account for initial seed quality and assess germination across a range of environmental conditions. In this article, we outline the steps of the dormancy classification process and the various corresponding methodologies for ex situ dormancy alleviation. We also highlight the importance of record‐keeping and reporting of seed accession information (e.g. geographic coordinates of the seed collection location, cleaning and quality information, storage conditions, and dormancy testing data) to ensure that these factors are adequately considered in restoration planning. [ABSTRACT FROM AUTHOR]

Downy mildew of common sage (Salvia officinalis), caused by Peronospora salviae-officinalis, has become a serious problem in sage production worldwide. The effect of temperature was determined for conidia germination and disease development. In vitro, conidial germination rate was highest at temperatures between 10 °C and 20 °C and was strongly reduced at temperatures above 25, but conidia were also able to germinate at 2 °C. Temperatures between 15 and 20 °C were most favourable for infection and disease progress in infection experiments in climate chambers, with highest sporulating leaf area observed at 15 and 20 °C, and highest symptomatic leaf area at 20 °C. P. salviae-officinalis is still able to infect sage plants at 5 °C, but sporulation was only observed at higher temperatures. Oospores developed 14 days after inoculation at 15 °C, and 8 days after inoculation at 20 and 25 °C. The infection trials also showed that dark incubation is not a prerequisite for successful infection of sage. Furthermore, P. salviae-officinalis needs two events of leaf wetness or high humidity to complete its asexual life cycle. First, a leaf wetness event of at least three hours is needed for conidial germination and penetration of the host. Second, high humidity of at least 90% is needed at the end of the infection cycle for sporulation. Seed washing revealed the presence of P. salviae-officinalis oospores in seed lots of sage suggesting that infested seeds might play a major role in the fast spread of sage downy mildew, which is an important finding for phytosanitary or quarantine measures. [ABSTRACT FROM AUTHOR]

Many seed quality tests are conducted by first randomly assigning seeds into replicates of a given size. The replicate results are then used to check whether or not any problems occur in the realization of the test. The two main tools developed for this verification are the ratio of the observed variance of the replicate results to a theoretical variance and the tolerance for the range of the results. In this paper, we derive the theoretical distribution and its related properties of the sequence of numbers of seeds with a given quality attribute present in the replicates. From these theoretical results, we revisit the two quality checking tools widely used for the germination test. We show a precaution to be taken when relying on the variance ratio to check for under- or over-dispersion of the replicate results. This has led to the development of tables providing credible intervals of the variance ratio. The International Seed Testing Association tolerance tables for the range of the results are also compared with tolerances computed from the exact theoretical distribution of the range, leading us to recommend a revision of these tables. [ABSTRACT FROM AUTHOR]

Germination of three soybean cultivars: Abelina, SG Anser and Merlin was examined in a laboratory study as affected by products containing effective microorganisms: EM5, EM Farma and EM Mulit Grower. Germination in an aqueous environment was the control treatment. Analysis of germination capacity after 5 and 10 days from the beginning of the experiment (as indicated by International Seed Testing Association) was based on two-way analysis of variance. A logistic function was used to analyse the average number of germinating seeds over time (for each cultivar × product). Based on this function, the rate of germination and the time (day) when the greatest number of seeds germinated were determined. Regardless of the applied product, cv. Abelina had the best germination performance at the first and second date of counting as its germination capacity was 55 and 86%, respectively. An application of EM Farma contributed to a significant increase in seed germination capacity at both the dates compared with the control and the remaining products. No significant differences in the number of germinated seeds counted after 5 and 10 days following EM application were found for cv. Merlin only. The highest number of germinated seeds at the logistic curve inflection point was observed for all the cultivars treated with EM Farma, their germination rate ranging from over 7 to 19% per 24 hrs. [ABSTRACT FROM AUTHOR]

An experiment was conducted during 2014-2015 to standardize the seed testing method in Kabuli chickpea MNK-1 by number of seeds and number of germination papers. Among the different testing methods 25 seeds per replication recorded highest seed germination percentage (91.58%), less number of fresh un-germinated seeds (1.91%), abnormal seedlings (4.00%), diseased seeds (2.33%) and significantly higher seedling vigour index-I and II (2215 and 6863), among the number of germination papers used 2+1 as in between paper method(Bottom 2 and one paper above) recorded significantly higher germination percentage (92.12%), less number of fresh un-germinated seeds (1.41%), abnormal seedlings (3.66%), diseased seeds (2.33%) and significantly higher seedling vigour index-I and II (2463 and 6900), when compared to other. Irrespective of number of germination paper and seeds used however, interaction of 25 seeds per replication and 2+1 between paper method of seed germination testing showed significantly germination percentage (96.50%), less number of fresh un-germinated seeds (0.00%), abnormal seedlings (1.00%), diseased seeds (1.00%) and significantly higher seedling vigour index-I and II (2844 and 7792) followed by 50 seeds per replication. [ABSTRACT FROM AUTHOR]

The present investigation was carried out for genetic divergence of barnyard millet (Echinochloa frumentacea (Roxb.) Link) germplasm during Kharif, 2014 at Research Block, Department of Crop Improvement and Seed Testing at Department of Seed Science and Technology, V. C. S. G. Uttarakhand University of Horticulture and Forestry, College of Forestry, Ranichauri (Uttarakhand) with 35 diverse genotypes as EC-134192, IC-543, EC-578, IEC-411, RAU-11, VL-222, IC-595, PRB-402, EC-756, RAU-2, VL-232, IEC-515, IC-542, IEC-111, TNAU-149, PRB-802, IEC-546, PRB-903, VL-174, IEC-523, PRB-401, IEC-566, IEC-513, PRB-904, VL-230, VL-239, TNAU-155, IEC-636, IEC-531, VL-182 and PRB-9402, of barnyard millet including three checks viz., VL-172, VL-207 and PRJ-1. In genetic divergence, all thirty-five genotypes were grouped by using Mahalanobis D? stastistic into 6 clusters irrespective of geographical diversity, indicating no parallelism between geographic and genetic diversity. The cluster pairs exhibiting very high inter-cluster distances were cluster IV and VI, cluster IV and V, cluster II and IV, cluster III and VI, cluster I and IV and cluster III and IV. Considering cluster mean and genetic distance the crossing between genotypes of clusters IV with genotypes of cluster VI and those genotypes of cluster V would be fruitful for obtaining transgrassive segregants for developing high yielding and better quality barnyard millet varieties. [ABSTRACT FROM AUTHOR]

Held on July 2017 during the 20th EAPR Conference in Versailles, France, the workshop intended (1) to review—and exchange with participants—some recent advances and concerns for the seed potato sector (new regulations, seed health, multiplication schemes including true potato seed, seed crop management, etc.) and (2) to define the main challenges for future research and improvement for seed potatoes production and regulation systems to secure the whole chain of potato production. [ABSTRACT FROM AUTHOR]

According to International Rules for Seed Testing, a germination test is performed with 400 seeds, subdivided into four replicates of 100 seeds. The empirical variance between the four replicate results was found by many authors to be smaller than random sampling variation. Hypotheses for sources for this underdispersion were developed, but no experimental proof was possible, as the population's true germination value is unknown. To overcome this obstacle, we performed two online ring tests with computer- generated seedling images. Seedlings had to be classified as normal, if the shoot/root ratio was between 0.5 and 2.0, otherwise as abnormal. Results showed significantly smaller variances between empirical replicate results than between true replicate values, confirming underdispersion. Rates of false normal and false abnormal classification of seedlings were 19.5 and 3.5%, respectively. Error rates are different between analysts and depend on the true replicate value. In replicates with many abnormal seedlings, the false normal rate is higher and the false abnormal rate is lower than in samples with few abnormal seedlings. This is the source of underdispersion and a direct result of decisions made by seed analysts. Pooling of replicate results of all analysts and recombining showed that underdispersion can be reduced significantly when each replicate is tested by a different analyst. Hence, replicates should be blinded and every replicate evaluated by another analyst. [ABSTRACT FROM AUTHOR]

Canada is the world's largest producer and exporter of flaxseed. In 2009, DNA from deregistered genetically modified (GM) CDC Triffid was detected in a shipment of Canadian flaxseed exported to Europe, causing a large decrease in the amount of flax planted in Canada and a major shift in export markets. The flax industry in Canada undertook major changes to ensure the removal of transgenic flax from the supply chain. To demonstrate compliance, Canada adopted a protocol involving testing grain samples (post-harvest) using an RT-PCR test for the construct found in CDC Triffid. Efforts to remove the presence of GM flax from the value chain included reconstituting major flax varieties from GM-free plants. The reconstituted varieties represented the majority of planting seed in 2014. This study re-evaluates GM flax presence in Canadian grain stocks for an updated dataset (2009-2015) using a previously described simulation model to estimate low-level GM presence. Additionally, losses to the Canadian economy resulting from the reduction in flax production and export opportunities, costs associated with reconstituting major flax varieties, and testing for the presence of GM flax along the flax value chain are estimated. [ABSTRACT FROM AUTHOR]

Micromorphological characteristics of the seed testa of 38 species belonging to 19 sections and seven subgenera of Allium from central Asia have been evaluated with a scanning electron microscope (SEM). Several taxonomically significant characters were found. The results showed that the epidermis consists of polygonal cells with different dimensions, that the cellular arrangement is tight or loose with or without reticulate tissue, and that the arrangement of cells is regular or irregular. The main variation was found in the anticlinal walls, of which the outline could be straight, straight to arched, arched or undulating like an S or U. Convex and (or) concave verrucate periclinal walls occurred in all species investigated. Based on the characteristics of the anticlinal and periclinal walls of the 38 species, six groups of Allium were distinguished, and a dichotomous key for them is presented. The cellular arrangement and periclinal and anticlinal wall traits of the 38 species of Allium were found stable and distinct within a species, but showed great differences among species. We conclude that seed epidermal characteristics provide useful and important information for distinguishing species of Allium, and thus they have taxonomic significance. [ABSTRACT FROM AUTHOR]

BACKGROUND There is a need to minimize economic damage by sorting infected seeds from healthy seeds before seeding. However, current methods of detecting infected seeds, such as seedling grow-out, enzyme-linked immunosorbent assays, the polymerase chain reaction (PCR) and the real-time PCR have a critical drawbacks in that they are time-consuming, labor-intensive and destructive procedures. The present study aimed to evaluate the potential of visible/near-infrared (Vis/NIR) hyperspectral imaging system for detecting bacteria-infected watermelon seeds. RESULTS A hyperspectral Vis/NIR reflectance imaging system (spectral region of 400-1000 nm) was constructed to obtain hyperspectral reflectance images for 336 bacteria-infected watermelon seeds, which were then subjected to partial least square discriminant analysis (PLS-DA) and a least-squares support vector machine (LS-SVM) to classify bacteria-infected watermelon seeds from healthy watermelon seeds. The developed system detected bacteria-infected watermelon seeds with an accuracy > 90% (PLS-DA: 91.7%, LS-SVM: 90.5%), suggesting that the Vis/NIR hyperspectral imaging system is effective for quarantining bacteria-infected watermelon seeds. CONCLUSION The results of the present study show that it is possible to use the Vis/NIR hyperspectral imaging system for detecting bacteria-infected watermelon seeds. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Copyright of Botany is the property of Canadian Science Publishing 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.)

Clavibacter michiganensis subsp. insidiosus (Cmi) is a seed-borne pathogen that causes bacterial wilt of lucerne (alfalfa, Medicago sativa). The pathogen has a limited distribution worldwide and is included in the A2 pest list of the European and Mediterranean Plant Protection Organisation (OEPP/EPPO). In South Africa, Cmi was first reported in 1967 in a few regions (Western Cape province and in the Eastern Cape), with the last doubtful listing in 1983 also reporting it from the Transvaal region (currently known as Gauteng, Limpopo, North West and Mpumalanga provinces). Subsequently, lucerne plants exhibiting bacterial wilt symptoms have not been observed in any region of South Africa. Nevertheless, for South Africa, Cmi is listed as "present, restricted occurrence" by the OEPP/EPPO. Therefore, the status of Cmi in South Africa was re-investigated through field inspections and seed testing. Field inspections of lucerne seed crops conducted in all production regions from 2006 to 2014 did not reveal any symptomatic plant. Seed testing of 67 representative commercial seed lots showed that Cmi was absent from all of the seed lots. Prior to testing the commercial seed lots, artificially inoculated seed lots were used to show that the serial dilution plate method was sensitive (0.1% detection limit). It was also shown that a published Cmi semi-selective glucose-yeast-carbonate agar medium containing kanamycin and cycloheximide was able to more readily reveal the presence of presumptive Cmi colonies than the media of the EPPO diagnostic protocol, and the International Seed Health Initiative ring test. [ABSTRACT FROM AUTHOR]

In 2012, Colletotrichum isolates were collected from field-grown safflower ( Carthamus tinctorius) crops in central Italy from plants exhibiting typical anthracnose symptoms. Colletotrichum isolates were also collected from seed surfaces and from within seeds. The genetic variability of these isolates was assessed by a multilocus sequencing approach and compared with those from Colletotrichum chrysanthemi and Colletotrichum carthami isolates from different geographic areas and other Colletotrichum acutatum sensu lato-related isolates. Phylogenetic analysis revealed that all of the strains isolated from C. tinctorius belonged to the species described as C. chrysanthemi, whereas all of the strains belonging to C. carthami had been isolated from Calendula officinalis. Phenotypic characterization of isolates was performed by assessing growth rates at different temperatures, morphology of colonies on potato dextrose agar ( PDA) and the size of conidia. All C. chrysanthemi isolates from safflower had similar growth rates at different temperatures, comparable colony morphologies when grown on PDA and conidial sizes consistent with previously described C. chrysanthemi isolates. Pathogenicity tests were performed by artificially inoculating both seeds and plants and confirmed the seedborne nature of this pathogen. When inoculated on plants, C. chrysanthemi caused the typical symptoms of anthracnose on leaves. This is the first record of this pathogen on C. tinctorius in Italy, and it presents an updated characterization of Colletotrichum isolates pathogenic to safflowers in Europe. [ABSTRACT FROM AUTHOR]

[Objective] This study aimed to investigate the inspection methods and quality grading standards for Codonopsis pilosula seeds. [Method] A total of 27 shares of C. pilosula seeds were collected and surveyed from six counties in Shanxi, Gansu and Shaanxi provinces. The inspection methods of various indicators, such as purity, 1 000-grain weight, germination rate, vitality and moisture content, were investigated in accordance with Rules for Agricultural Seed Testing (GB/T 3543.1-7, 1995), to develop the appropriate quality inspection method for C. pilosula seeds. Based on the developed inspection method and procedures, the quality of 27 shares of C. pilosula seed samples from different regions was inspected, thus establishing quality grading standards for C. pilosula seeds with K-center clustering method. [Result] C. pilosula seeds are suitable to be cultivated in cool regions. The optimal germination temperature was 25 °C; the optimal germination bed was gauze bed; the optimal staining conditions were: staining temperature 40 °C, TTC concentration 0.5%, staining time 4 h. On the basis of cluster analysis, the quality of C. pilosula seeds could be divided into three grades according to five indicators, including the purity, 1 000-grain weight, moisture content, vitality, and germination rate. Specifically, vitality and germination rate were important factors of grading standards due to the significant differences, followed by purity, 1 000-grain weight and moisture content. [Conclusion] This study provided an important basis for standardized cultivation and industrial development of C. pilosula. [ABSTRACT FROM AUTHOR]

Copyright of Acta Scientiarum: Agronomy is the property of Universidade Estadual de Maringa 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 Revista Brasileira de Biociencias is the property of Revista Brasileira de Biociencias 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.)

Fungi are important in soils as both decomposers and plant symbionts, and an understanding of the composition of their complex communities is thus indispensable to answer a variety of ecological questions. 454 Pyrosequencing is currently the method of choice for the in-depth analysis of fungal communities. However, the interpretation of its results is complicated by differences in data analysis approaches that make inter-study comparisons difficult. The pyrosequencing studies published so far have also used variable molecular targets in fungal rDNA. Although the ITS region and, in particular, ITS1 appear to be the most frequent sequencing targets, the use of various primers with different coverages of fungal groups remains a serious problem. Sequence length limits also vary widely across studies, and in many studies, length differences may negatively affect sequence similarity clustering or identification. Unfortunately, many studies neglect the need to correct for method-dependent errors, such as pyrosequencing noise or chimeric sequences. Even when performed, error rates in sequences may be high, and consensus sequences created by sequence clustering therefore better represent operational taxonomic units. We recommend a data analysis workflow that includes sequence denoising, chimera removal, sequence trimming before clustering and random resampling before calculating diversity parameters. The newly developed free pipeline (SEED) introduced here can be used to perform all the required analytical steps. The improvement and unification of data analysis procedures should make future studies both more reliable and comparable and allow meta-studies to be performed to provide more general views on fungal diversity, biogeography or ecology. [ABSTRACT FROM AUTHOR]

Although farmers in the Malian Sahel depend on millet for survival, demand and supply constraints have impeded their use of certified seed. We use data collected from households, vendors and seed samples to test the way market purchases of grain and seed affect household food consumption and millet genetic diversity. Purchase of millet grain in markets contributes to food security but reduces dietary diversity - suggesting that scarce cash was directed toward meeting staple food needs first. Farmers purchased millet grain for seed only in the site with riskier rainfall and smaller market fairs. Although they were more likely to purchase in markets where the genetic dissimilarity of seed was higher, purchasing seed in markets was negatively associated with on-farm diversity. Seed shortage rather than variety experimentation appears to be the motivation for seed purchase. hitroducing certified seed in rural markets through small-scale traders will require the provision of market services and promotional efforts. [ABSTRACT FROM AUTHOR]

We have determined the parameters of oil expression process for non-typical seeds of oil-producing plants, such as quince tree, safflower, fennel-flower, cuckoo-flower, tarweed, lallemantia, sea-buckthorn, borage, evening primrose, mustard, and others. The relative moisture of most of the seeds tested ranged from 5.5% to 8.9%. The values of the oil point pressure obtained for the seeds permitted detailed classification of the plant species under study into 7 seed hardness groups. The largest group belonged to the pressure range from 10 to 15 MPa (oil flax, spring rapeseed cvs Bronowski, Mazowiecki, and Star, spring rape cv. Porkland and local population, oil radish, spring camelina, mustard cv. Małopolska, evening primrose cv. UWM). The oil content in this group was above 30%, and in the case of rapeseed cv. Mazowiecki and Bronowski it was 40%. The values of compression energy obtained for the materials studied in the oil test ranged from 3.69 J (oil sunflower cv. Wielkopolski) to 64.18 J (sea-buckthorn). [ABSTRACT FROM AUTHOR]

The detection and quantification of the prevalence of genetically modified organism (GM) contamination in seed exports is a critical element of regulatory compliance. While the procedures to reliably detect high levels of GM contamination are well understood, no comparable statistical approaches are available for the quantification of levels of GM prevalence below the established detection rate of standard tests. We present a simple statistical approach based on simulation modelling for the quantification of low levels of GM contamination. The approach can be modified to match any sampling regime and can account for rates of false positive and negative assay results. The application of this method is demonstrated using the low level of contamination in Canadian flax breeder seed lots by the GM flax variety ‘Triffid’. We show that GM contamination is likely present in seed lots at rates between two GM seeds per million and six seeds per hundred thousand. We also show that this low level of presumed contamination is indistinguishable from the number of positive tests expected from a clean seed lot given the potential rates of false positive tests. [ABSTRACT FROM AUTHOR]

This paper briefly reviews research on the causative agents of blackleg and soft rot diseases of potato, namely Pectobacterium and Dickeya species, and the disease syndrome, including epidemiological and aetiological aspects. It critically evaluates control methods used in practice based on the avoidance of the contamination of plants, in particular the use of seed testing programmes and the application of hygienic procedures during crop production. It considers the perspective of breeding and genetic modification to introduce resistance. It also evaluates the application of physical and chemical tuber treatments to reduce inoculum load and examines the possibility of biocontrol using antagonistic bacteria and bacteriophages. [ABSTRACT FROM AUTHOR]

The seed-borne mycoflora of sorghum and foxtail millet collected from different growing areas in South Korea were isolated and taxonomically identified using dry inspection, standard blotter and the agar plate method. We investigated the in vitro and in vivo germination rates of disinfected and non-disinfected seeds of sorghum and foxtail millet using sterilized and unsterilized soil. The percent recovery of seed-borne mycoflora from the seed components of sorghum and foxtail millet seeds was determined and an infection experiment using the dominant species was evaluated for seedling emergence and mortality. A higher number of seed-borne fungi was observed in sorghum compared to that of foxtail millet. Eighteen fungal genera with 34 fungal species were identified from the seeds of sorghum and 13 genera with 22 species were identified from the seeds of foxtail millet. Five dominant species such as Alternaria alternata, Aspergillus flavus, Curvularia lunata, Fusarium moniliforme and Phoma sp. were recorded as seed-borne mycoflora in sorghum and 4 dominant species (Alternaria alternata, Aspergillus flavus, Curvularia lunata, Fusarium moniliforme) were observed in foxtail millet. The in vitro and in vivo germination rates were higher using disinfected seeds and sterilized soil. More seed-borne fungi were recovered from the pericarp compared to the endosperm and seed embryo. The percent recovery of seed-borne fungi ranged from 2.22% to 60.0%, and Alternaria alternata, Curvularia lunata and 4 species of Fusarium were isolated from the endosperm and embryo of sorghum and foxtail millet. Inoculation of the dominant seed-borne fungi showed considerable mortality of seedlings. All the transmitted seed-borne fungi might well be a primary source of infection of sorghum and foxtail millet crops. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the influence of different soaking and cooking methods on contents of selected nutrients in legume seeds. The experimental material were dried kidney-bean seeds and soya bean seeds originating from the collection of Krakow's Plants and Seeds Horticulture POLAN LTD. Technological treatment of seeds was performed in two stages: (1) cold and hot soaking, (2) cooking with three different devices: electric and induction stoves and microwave apparatus. The experimental material was determined for contents of: dry, matter, protein, fat, ash. carbohydrates and selected mineral compounds (Ca, Mg, Na, K). The soaking and cooking of the seeds were observed to affect an increase in contents of protein, fat, ash, calcium and sodium in dry matter as well as a decrease in contents of digestible carbohydrates, potassium and magnesium. A more favorable method of soaking kidney bean seeds turned out to be hot soaking, which caused smaller losses of nutrients and shortened significantly the whole process. Cooking soya bean and kidney bean seeds with electric and induction stoves facilitated better protein preservation in comparison to the thermal treatment performed in a combined microwave oven. [ABSTRACT FROM AUTHOR]

Methanolic extract of ajwain seeds (wild celery seed) has been analyzed by GC-MS to establish its chemical constituents. The extract is found to have good antibacterial property to selected micro-organisms and hence has been applied on cotton fabric to impart antimicrobial property and to evaluate its wash durability. It is found that the treated fabric shows good antibacterial property to both Gram positive and Gram negative organisms, but has poor wash durability. Hence, to fix the herbal extract on cotton fabric different techniques, like microencapsulation, cross-linking and a combination of both, have been employed. It is observed that herbal extract encapsulated with acacia gum is durable up to 15 normal wash cycles. Herbal extract cross-linked with a resin is found to be durable up to 10 washes. In both the cases, fabric lost one of the physical properties like crease recovery angle or tensile strength. However, a combined technique shows that treated fabrics are durable up to 15 washes without compromising physical properties. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental 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 Field & Vegetable Crops Research / Ratarstvo i povrtarstvo is the property of Institute of Field & Vegetable Crops 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.)

Effective germplasm conservation through seed banking requires that the viability status of every accession in the seed bank be known. This is normally done by conducting a germination test but is, at times, constrained by the presence of seed dormancy in some of the species. While dormancy release protocols have been developed for a majority of species, the same are lacking for others. The objective of this study was to determine the dormancy releasing procedure of selected species in the family Amaranthaceae to develop a germination-testing protocol for them. In this study, the influence of chilling, incubation temperature, potassium nitrate (KNO3), and dehusking was investigated for 10 wild species. The effect of temperature on seed germination of species in the family was found to be significant (p ≤ .05) with most species performing better at alternating temperatures of 35°C/20°C as compared with constant ones. The effect of dehusking was highly significant on seed germination with the removal of seed covering structures promoting germination in Gomphrena celosioides and Aerva lanata. Application of chilling or KNO3 treatment as dormancy release mechanisms, while causing a positive effect in some species, reduced germination in others. Out of the 10 species that were investigated in the present study, 6 had their seed-testing protocols successfully developed. [ABSTRACT FROM AUTHOR]

The fungus Alternaria padwickii has been frequently detected in seed tests of rice collected from commercial crops in Corrientes Province, Argentina. This pathogen causes germination inhibition, seedling death or spotted grains and is the causal agent of Alternaria leaf spot. The pathogen survives as mycelia and sclerotia on seeds, plant debris and soil. Four detection methods were compared in laboratory tests, to select the best for a quick identification of the fungus in seeds. The methods were (i) Blotter Test (ii) Potato glucose agar, (iii) Bean agar (BA) and (iv) Malt extract agar. Twenty seed samples of different varieties of rice collected from Empedrado, Goya, Itá Ibaté, La Cruz, Mercedes, Paso de los Libres and Perugorría localities (Corrientes, Argentina), were analyzed in the assays. Theanova test and the Tukey multiple range test were applied on the data to compare the A. padwickii incidence among the varieties and detection methods. BA method was found more sensitive than other methods for A.  padwickii. The incidence values ranged from 3.6 to 76%. The statistical analysis demonstrated that the BA method was the most efficient for the detection of seed pathogens, and it could be useful in studies of transmission and chemical control. [ABSTRACT FROM AUTHOR]

Copyright of Field & Vegetable Crops Research / Ratarstvo i povrtarstvo is the property of Institute of Field & Vegetable Crops 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.)

Annona squamosa and Catunaregam nilotica seeds and oils were characterized for their approximate analysis and physico-chemical properties. The oil and protein contents were 26.8, 17.5 and 40.0, 22.2%, in A. squamosa and C. nilotica seeds, respectively. The oils were extracted using cold extraction (CE) and Soxhlet extraction (SE) methods. Fatty acids and tocopherols were determined by GC–MS and HPLC, respectively. Generally the physico-chemical properties and fatty acids were not significantly ( P ≤ 0.05) affected by the extraction methods. The major fatty acids of A. squamosa oil extracted by CE and SE were oleic 49.2 and 50.5%, linoleic 22.3 and 22.7%, palmitic 15.6 and 15.2%, and stearic 10.6 and 9.3%, respectively. While the major fatty acids in C. nilotica oil extracted by CE and SE were oleic 10.5, and 10.4%, linoleic 63.1 and 63.4%, palmitic 9.7 and 9.8% and stearic 5.1 and 5.4%, respectively. The tocopherol content of CE and SE extracted oils from A. squamosa amounted to 16.6 and 15.5 and from C. nilotica amounted to 110.5 and 107.7 mg/100 g oil, respectively, with delta-tocopherol as the predominant tocopherol in A. squamosa oil, and beta-tocopherol in C. nilotica oil. The total amount of amino acids was found to be 7.266 and 14.202 g/100 g protein, in seeds of A. squamosa and C. nilotica, respectively. [ABSTRACT FROM AUTHOR]

The detection of Ralstonia solanacearum (biovar 2A) in stems of symptomless plants before harvest of the potato crop, instead of tubers, would not only save highly valued planting material but would be less time-consuming and would also enhance farmers’ market decisions. Although pathogen detection in stems has been proven efficient for ring rot, this has never been investigated for bacterial wilt (BW). Therefore the possibility of detecting BW latent infection in stem pieces about three weeks before harvest was assessed in 57 fields of the Andean highlands of Peru. Two sensitive, specific and user-friendly serological methods were used to detect the pathogen in latently infected tubers and stems: double-antibody sandwich (DAS)-ELISA and indirect ELISA on nitrocellulose membrane (NCM) after enrichment of the plant extracts in a semi-specific broth. Optimum sample sizes of stems and tubers were evaluated for 37 potato crops showing between 0 and 0·1% BW incidence using a binomial distribution model to calculate the detection probabilities. Although results of detection using the two serological techniques had 100% concordance, detection probabilities were higher using DAS-ELISA, whatever the plant part tested. BW detection probabilities were higher for tubers than for stems; a 99% detection probability was obtained by analysing 400 stems sections or 250 tubers using DAS-ELISA. Detection of BW infection in symptomless plants 20 days before harvest using post-enrichment DAS-ELISA is a reliable and user-friendly technique that can easily be used by national plant protection services and seed programmes in developing countries. [ABSTRACT FROM AUTHOR]

Designing good or optimal seeds is a key factor for local homology search in bioinformatics. Continuous seeds have existed for nearly 20 years used by BLAST series programs. Recently, spaced seeds, which were introduced by PattenHunter program, were shown to be more sensitive and faster than continuous seeds under the same similarity level. However, there are 2 main disadvantages for space seeds: (i) It assumes that only matches and mismatches occur within seed alignments, but not insertions and deletions (indels); (ii) calculating optimal spaced seeds is an NP-hard problem. Introduction for indel seeds solved the first problem, but the second is getting much harder because of its higher exponential level. In this paper, we introduce an efficient way of designing good (even optimal) indel seeds under "indel overlap complexity" model, and it can be calculated in polynomial time. We calculate indel seeds from weight of 11 to 15. The result shows that indel seeds have higher sensitivities than spaced ones and our algorithm finds good indel seeds very quickly. [ABSTRACT FROM AUTHOR]

Seed pathology involves the study and management of diseases affecting seed production and utilization, as well as disease management practices applied to seeds. In this paper, three aspects of seed pathology are discussed: research innovations in detection of seedborne pathogens and elucidation of their epidemiology; advances in development and use of seed treatments; and progress toward standardization of phytosanitary regulations and seed health testing methods. The application of nucleic-acid based detection methods in seed health testing has been facilitated by integrating conventional or real-time PCR with other technologies (e.g., BIO-PCR, IMS-PCR, MCH-PCR). PCR-based methods and pathogen marker technologies are being applied to epidemiological research on seedborne pathogens, e.g., seed transmission mechanisms, the influence of external biotic and abiotic factors on seed transmission, and tracking progress of seed-transmitted pathogens. Seed treatment use is discussed in terms of the revolutionary expansion in seed-applied insecticide use, impacts of new fungicide active ingredients, and the effects of some seed treatments on crop physiology. International seed trade has been affected significantly by changing phytosanitary regulations, not always based on science. Efforts are underway to revise phytosanitary regulations to reflect pest risk analysis outcomes and to develop standards for seed health testing methods that facilitate safe and efficient international trade in seeds. [ABSTRACT FROM AUTHOR]

The article reports on a study of the detection of Clavibacter michiganenis ssp. insidiosus (Cmi) in alfalfa seed. It used the conventional polymerase chain reaction (PCR) assay and the real-time Taqman PCR assay in identifying Cmi in alfalfa seed. It also inoculated several cultivars of alfalfa seedlings that founds out that foliage symptoms of Cmi included stunting, leaf scorch, yellowing, and wilting.

Many studies now suggest that pathogens can cause high levels of mortality in seeds and seedlings. Recruitment from seed to sapling is an important bottleneck for many tree species, and if specialist or generalist pathogens have differential negative effects among species of juvenile trees, then they may have a significant impact on forest community structure. To explore the effects of differential pathogen attack among tropical tree species, we quantified pathogen attack on the seeds of 16 tree species from the southeastern Peruvian Amazon and asked which seed characteristics, including size, hardness, germination time and mode, shade tolerance, and fruit type, were most closely correlated with susceptibility to pathogens. Shade tolerance and seed weight were positively and significantly correlated with susceptibility to pathogen attack by ecological trait regressions (ETRs), and correspondence analysis indicated that there might be increased attack rates in species with brightly colored, pulpy fruits (often dispersed by primates). Only shade tolerance was significantly correlated with pathogen attack when the analyses accounted for phylogenetic relatedness between species. Thus, contrary to standard predictions of size-defense ratios, our results suggest that larger, shade-tolerant seeds tend to be more susceptible to pathogen attack than smaller, light-dependent seeds. Moreover, differential pathogen attack may shape seed community composition, which may affect the successful recruitment of adults. [ABSTRACT FROM AUTHOR]

Quantitative real-time PCR (polymerase chain reaction) assays are increasingly used to measure quantities of nucleic acids in samples. They may be used to provide a high-throughput alternative to more traditional biological assays. In this case, a calibration process may be required to convert the PCR measurements onto a more relevant scale. This is most commonly undertaken using simple linear regression. However, such calibration models are usually unrealistic since they ignore the various sources of variation associated with the PCR and conventional assays. Taking account of these various sources is necessary if the errors associated with predictions based on the calibration model are to be well estimated. In this article, we demonstrate a more complete approach to calibration of quantitative PCR. As an example, we develop a Bayesian calibration model for measuring the quantity of the fungus common bunt ( Tilletia caries) on wheat seed, based on our understanding of the properties of the assays. As well as illustrating the steps in developing such a model, we show how the fit of the model might be assessed. [ABSTRACT FROM AUTHOR]

The genetic diversity of 76 accessions of lima bean (Phaseolus lunatus L.), collected mostly from home gardens, was assessed with AFLPs and seed descriptors to evaluate the potential for recovering a lost ex situ collection in Cuba. The sample contained 60 accessions collected from 25 home gardens in the three main geographical regions of Cuba and represented the three cultivated types found on the island. Four more accessions were part of the former ex situ collection and the remaining 12 accessions were selected from the world bean collection held at the International Center for Tropical Agriculture. Some morphological measurements discriminated among cultivated types. The analysis of 62 polymorphic bands obtained with two AFLP primer combinations indicated that the three cultivated bean types were comparable in terms of molecular diversity and that no pattern of variation was associated with geographical distribution. However, a multiple correspondence analysis with the same molecular data detected different genetic groups. Three of these groups included all the cultivated accessions collected from home gardens, but could not be explained by the seed descriptors. The results therefore suggest that a scientifically sound collecting strategy to recover the former Cuban ex situ gene bank should consider combining geographical, morphological, and molecular data. The findings also suggest that any proposed methodologies should be considered before developing a conservation strategy based on an ex situ or combined ex situ and in situ approaches. [ABSTRACT FROM AUTHOR]