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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]

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.

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]

Differences in the seed testing rules for domestic trade (Regulation on the quality of seeds of agricultural plants Sl. SFRJ 47/1987) and export (International rules for seed testing - ISTA rules) are the reason for the lack of consistency in the seed testing and the interpretation of the obtained results. For certain species, there are even different test methods, which can additionally lead to inconsistent test results of the same seed lot. Therefore, the objective of this paper is to highlight the differences that exist and point out the need to harmonize national and international rules for seed testing. Through this review, the main differences during sampling and the most common methods of seed testing are shown: purity, germination, 1000 seed weight and moisture content. Differences in the quality control of test conditions are also shown, which laboratories that have both, national and international accreditation, must pay attention to. International rules (ISTA) are changed every year, at the initiative of member laboratories, based on new research and experiences from laboratories around the world. Harmonization of national and international rules for seed testing would greatly facilitate work in laboratories and contribute to uniform criteria for seed testing and reporting of test results.

Seed germination is one of the most important factors determining the crop production and its quality. Seed testing has been developed to aid agriculture to avoid some of the hazards of crop quality and production by furnishing the needed information about different quality attributes as purity, moisture, capacity of germination, vigorously and health. The importance of seed testing was realized more than one hundred years ago. This study reflects the results obtained in the research Laboratory for seed quality control at the University of Life Sciences “King Mihai I” from Timișoara, using the standard methods based on a selection of twenty-seven wheat varieties from Agricultural Research and Development Station Lovrin regarding germinative energy and capacity of germination in optimal conditions of temperature, humidity and light. Seed germination was determined using two approved Standard ISTA methods (SR 1634-the standard which establishes the maximum germination potential of seeds), the first one using the Jacobsen germinating apparatus and the second one with the seed germination cabinet. The determinations were made in four sets of 1000 seeds each and the results were obtained by calculating the mean value. The differences of values between the two methods, occur due to the fact that the filter paper used in the Jacobsen germinator was too thin, this leading to a higher percent of abnormal germs. [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.

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]

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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]

Highlights • Seed analysis is an indispensable procedure to determine the seeds quality and its value for sowing. • To obtain seeds in accordance to legislation, the laboratories must follow uniform procedures. • The CoIoT, allows the continuous acquisition and recording of the equipment contextual states. • The middleware send alerts to its users, always when the equipment are operating out of standard. • The proposed solution was evaluated using the Technology Acceptance Model. Abstract The lack of functional, calibrated equipment, along with using inconsistent testing method contribute to the variable, unreliable results produced by seed laboratories. The objective of this article is present to presente the development of an integrated system consisting of hardware, middleware, and application to continuously monitor and record the performance of seed testing equipment from the beginning to the completion of each test in seed testing laboratories. The central element of the proposed system is the CoIoT middleware (Context + IoT), which provides mechanisms for managing IoT devices and context awareness mechanisms to monitor and record the equipment functions, throughout the seed testing processes. The developed system was tested in the Official Seed Analysis Laboratory (OSTL) of the Brazilian Agricultural Research Corporation (Embrapa). The proposed system was evaluated using the Technology Acceptance Model (TAM), which considers aspects of ease of use and usefulness. To validate the results, a scale of 1 (user totally disagree) to 5 (user totally agree) was used. For ease of use the average was of 4.7, and for usefulness, the average was of 4.4. The results achieved are promising, which encourages the continuity of research to further optimize CoIoT. [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]

Abstract The study describes a novel diagnostic protocol based on a loop-mediated isothermal DNA amplification (LAMP) for identification of wheat grains infection by Tilletia laevis , Tilletia caries (common bunt) and Tilletia controversa (draft bunt). The presented data showed that the LAMP analysis is a simple, specific and rapid method that could be used for detection of Tilletia spp. in contaminated grain samples. The lowest DNA concentration required for the successful detection of Tilletia spp. strains were estimated to be 0.001 ng/μl. Simultaneously the detection limit for wheat grain contamination by T. caries and T. laevis teliospores was estimated at 20 μg per 100 g of grain. For T. controversa detection limit was lower and was approximately 20 mg of teliospores per 100 g of grain. The negative results of the LAMP reactions were achieved for the most common fungal species colonizing wheat grain like Fusarium spp., Alternaria sp., Cladosporium sp., Helminthosporium sp., and Penicillium sp. Highlights • LAMP assay allowed to detect wheat grain contamination by T. caries , T. laevis and T. controversa. • The detectable DNA concentration level is 0.001 ng/μl. • Limit of detection of T. caries and T. laevis teliospores is 20 μg per 100 g of grain. [ABSTRACT FROM AUTHOR]

Wheat blast is a devastating disease caused by the pathogenic fungus Pyricularia oryzae. Wheat blast first emerged in South America before more recently reaching Bangladesh. Even though the pathogen can spread locally by air-dispersed spores, long-distance spread is likely to occur via infected wheat seed or grain. Wheat blast epidemics are caused by a genetic lineage of the fungus, called the Triticum lineage, only differing from the other P. oryzae lineages by less than 1% genetic divergence. In order to prevent further spread of this pathogen to other wheat-growing areas in the world, sensitive and specific detection tools are needed to test for contamination of traded seed lots by the P. oryzae Triticum lineage. In this study, we adopted a comparative genomics approach to identify new loci specific to the P. oryzae Triticum lineage and used them to design a set of new markers that can be used in conventional polymerase chain reaction (PCR), real-time PCR, or loop-mediated isothermal amplification (LAMP) for the detection of the pathogen, with improved inclusivity and specificity compared to currently available tests. A preliminary biological enrichment step of the seeds was shown to improve the sensitivity of the tests, which enabled the detection of the target at an infection rate as low as 0.25%. Combined with others, this new toolkit may be particularly beneficial in preventing the trade of contaminated seeds and in limiting the spread of the disease.

Abstract Species of the Carapa spp. complex, occurring in the Neotropics, Africa and India, have multiple uses, including timber, with the seed oil being used in phyto-pharmaceutical products and cosmetics. This study aimed to determine the thermal ranges of the germination process, comparing germination criteria used by seed physiologists and seed technologists, and to suggest recommendations for seed quality assessment. Germination was assessed at constant temperatures between 10 ─ 40 °C using three germination criteria: (1) radicle length ≥ 0.5 cm (physiological criterion); (2) epicotyl length ≥ 1 cm; and (3) epicotyl length ≥ 5 cm (criterion for seed quality tests). The base temperature was similar for the three criteria and ranged between 10 ─ 2 °C. The Maguire’s Speed Index indicated 30 °C as most adequate. However, the upper temperature limit differed: for radicle protrusion it was above 40 ºC; and for both epicotyl lengths, it was between 35 ─ 40 °C. Seed coat removal accelerated the germination process of these recalcitrant seeds, and is recommended for seed quality assessment, which allows completion of the germination trial in approximately one month.

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]

Campomanesia guazumifolia (Cambess.) O. Berg. is a native fruit species, with ecological importance and potential to be exploited by food and medical industries. There is a lack of studies enabling its on-site conservation and propagation for commercial purposes. The objective of this work was to morphologically characterize the fruit, seed and seedling development stage of this species, as well as to determine an efficient protocol for the germination test, aiming at the commercial production of seedlings. Different temperatures (20, 25, 30 and 20-30 °C), substrates (blotting paper, sand and vermiculite) and light regimes (presence and absence) were tested in order to evaluate the germination power of seeds. Fruits are bacoid, rounded, with a fleshy pericarp and hairy surface, and with an intense yellow coloration. Seeds have a reniform shape and a lateral recess, with a membranous, brown and verrucose-glanulose tegument. It has a crass embryo, with a well developed hypocotyl-radicle axis and vestigial cotyledons. Seedlings are epigeal and phanerocotylar. It is recommended to conduct the germination test for the species with temperatures of 25 or 30 °C, on paper substrates, with light presence or absence, and with the first test count performed 23 days and the final count 50 days after sowing. [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]