Samples Of Seeds Research Articles

Batı Karadeniz Bölgesi’nde fasulye tohumlarında bulunan fungal hastalıkların belirlenmesi

Bu çalışma Batı Karadeniz Bölgesi’nde Zonguldak, Bartın ve Karabük illerinde fasulye ekiliş alanlarından toplanan fasulye tohumlarında görülen fungal hastalık etmenlerinin belirlenmesi amacıyla 2012-2014 yılları arasında yürütülmüştür. Tohum örnekleri sürvey yapılan illerdeki seralardan toplanmıştır. Bu tohumlardan funguslar izole edildikten sonra, izolatlar hem morfolojik hem de moleküler olarak teşhis edilmiştir. Çalışma sonucunda tohum örneklerinden, Pseudocercospora griseola (%53), Stemphylium vesicarium (%14.5), Fusarium oxysporum (%6.5), Fusarium solani (%5.25), Stemphylium globuliferum (%4.5), Stemphylium herbarum (tel: Pleospora herbarum) (%2), Fusarium sambucinum (%1), Trichothecium roseum (%0.75) ve Paecilomyces sp. (%2.5) bitki patojeni fungal türler elde edilmiştir.

EFFECT OF STORAGE CONTAINERS AND SEED TREATMENTS ON SEED GERMINATION AND VIGOUR OF BLACK GRAM (VIGNA MUNGO (L.) HEPPER)

One of the most important basic needs for higher agricultural production is quality seed, characterized by high viability and vigour. Maintenance of seed viability and vigour from Harvest till the next growing season is of the utmost importance in a seed production programme. During seed storage, qualitative and quantitative losses of up to 20% have been reported in India. The poor seed quality may also be due to the poor storability which is very often being decided by the internal and external factors. In pulses, the major cause for seed deterioration during storage is bruchid damage. In this context, evolving an improved storage strategy to prolong the shelf life of seeds under ambient storage conditions with easily available cost-effective resources was carried out. The experiment was conducted at the Department of Genetics and Plant Breeding, Faculty of Agriculture, Annamalai University, Annamalai nagar. Freshly harvested seeds of black gram cv. ADT 3 were cleaned and graded using BSS, 8x8 wire mesh sieve. Then seeds were dried under sunlight to bring the moisture content to required level (8.5%). The seeds were treated with Thiram @ 2g kg-1, Neem oil @ 10ml kg-1 and Malathion dust @ 200 mg kg-1. Two hundred and fifty grams of seeds from all treatments along with control were packed in two containers viz. cloth bag and polythene bag (700 gauges) with three replication and stored in at ambient temperature (30o c – 35o c) and relative humidity of 52-80%. Seed samples were drawn from each replication at monthly interval for assessing the viability and vigour. Germination test was conducted in between paper method and seedlings were evaluated on seventh day for vigour index bruchid infestation. The untreated seeds recorded lower germination per cent and vigour index after seven months of storage. There was no bruchid damage on seeds treated with neem oil @ 10ml kg-1 and thiram @ 2g kg-1. It was concluded that the shelf life of black gram seeds could be increased by

Analytical Concentrations of Some Elements in Seeds and Crude Extracts from Aesculus hippocastanum, by ICP-OES Technique

The metal content in some samples of horse chestnut seeds (Aesculus hippocastanum) was monitored over time (years 2016–2019) considering the two most common and representative Mediterranean varieties: the pure species (AHP, which gives white flowers) and a hybrid one (AHH, which gives pink flowers). The selected elemental composition of the samples was determined by applying the Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) technique. Several samples obtained from different preliminary treatments of the peeled seeds were examined, such as: (i) floury samples (wild-type) mineralized with the wet method; (ii) the ashes of both AHP and AHH varieties; (iii) the fraction of total inorganic soluble salts (TISS). Furthermore, the hydroalcoholic crude extracts (as a tincture) were obtained according to the official Pharmacopoeia methods, and the relevant results were compared with those of a commercial sample, an herbal product-food supplement of similar characteristics. The main characteristics of this research work underline that the two botanical varieties give different distinctive characters, due to the Fe content (80.05 vs. 1.42 mg/100 g d.s., for AHP and AHH wild-type flour samples, respectively), along with K, Ca, Mn, Ni and Cu, which are more abundant in the AHP samples. Furthermore, the Principal Component Analysis (PCA) was applied to the experimental dataset in order to classify and discriminate the samples, in relation to their similar botanical origin, but different for the color of the bloom. These results can be useful for the traceability of raw materials potentially intended for the production of auxiliary systems of pharmacological interest.

Microwave pretreatment on microstructure, characteristic compounds and oxidative stability of Camellia seeds

Camellia is an important woody oil crop and a primary source of edible vegetable oil. To optimize the extraction process of camellia (Camellia oleifera Abel.) seed oil, the similar impacts of microwave (MV) pretreatment (640 W, 0–8 min) on microstructure of camellia seeds (i.e. colour, oxidation-stability changes, tocopherol contents, sterol, squalene compounds, and fatty acid (FA) compositions were investigated. Generally, total carotene and sterol and squalene compounds of camellia oil were higher in microwave pretreated seeds than which in raw seeds (control). Seed samples were heated with the microwave (7%–8%) for 5 min, to demonstrated the excellent oxidative stability during accelerated oxidation. Tocopherol composition of the oil reached the maximum at different microwave treatment times, according to different moisture contents of camellia seeds. The fatty acid composition of microwave-pretreated camellia seeds variated insignificantly (p > 0.05). In conclusion, microwave pretreatment could improve the content of characteristic chemical composition and oxidative stability of camellia oil, while the moisture content and microwave time of camellia seeds needed to be controlled before oil extraction.

Chemical composition of roselle (Hibiscus sabdariffa l.) seeds fermented at varying durations

A study was carried out to determine the chemical composition of roselle seeds fermented at varying durations. One kg cleaned Roselle seeds were soaked in 3L of water for 8 hours. The soaked seeds were drained and fermented for 0, 24, 48, 72 and 96 hours as treatments. Samples of fermented roselle seeds at different duration of fermentations were analyzed for chemical composition including anti-nutritional factors. The results showed that there was significant (P<0.05) effect of fermentation duration on chemical composition and antinutritional factors of roselle seeds. Dry matter and crude protein content increased as fermentation duration increased from 0 to 96 hours. The highest dry matter (91.87%) and crude protein (35.05%) were obtained at 96 hours while crude fibre and ether extract decreased with increased fermentation duration. Crude fibre (6.55%) and ether extract (26.79%) were highest at 0 hours. Ash and nitrogen free extract content ranged from 5.41 – 5.78 % and 30.62 – 39.19 %, respectively. Anti-nutritional factor contents declined withincreased fermentation duration. The lowest values for saponin (2.02%), tannin (0.15%), phytic acid (5.44%) and trypsin inhibitor (8.93%) were obtained at 96 hours fermentation. It can be concluded that roselle seeds fermented for 96 hours enhanced nutrient availability and significantly reduced tannin, phytate, saponin and trypsin inhibitor anti-nutritional factors.

Seasonal Variation in Aflatoxin Levels in Edible Seeds, Estimation of Its Dietary Intake and Vitamin E Levels in Southern Areas of Punjab, Pakistan.

A total of 779 samples of edible nuts (melon seeds, watermelon seeds, pumpkin seeds, and cantaloupe seeds) from Southern Punjab (Pakistan), were collected during the summer and the winter seasons. The natural occurrence of aflatoxins (AFs) and vitamin E (tocopherols) levels were investigated using HPLC. The results have shown that 180 (43.4%) of samples from the winter season and 122 (33.4%) samples from the summer season were found positive for AFs. Elevated average levels of total AFs (20.9 ± 3.10 μg/kg, dry weight) were observed in watermelon seeds without shell, and the lowest average amount (15.9 ± 3.60 μg/kg) were documented in melon seeds without shell samples from the winter season. An elevated average amount of total AFs 17.3 ± 1.50 μg/kg was found in pumpkin seeds available without a shell. The results have documented a significant difference in total AFs levels in edible seeds available with shells versus without shells (α = 0.05 & 0.01). The highest dietary intake of 6.30 μg/kg/day was found in female individuals from consuming pumpkin seeds (without shell) in the winter season. A value of 3.00 μg/kg/day was found in pumpkin seed without shell in the summer season in female individuals. The highest total tocopherol levels were 22.2 ± 7.70 ng/100 g in pumpkin seeds samples from the winter season and 14.5 ± 5.50 mg/100 g in melon seed samples from the summer season. The variation of total tocopherol levels in edible seeds among the winter and summer seasons showed a significant difference (p ≤ 0.0054), except watermelon seeds samples with non-significant differences (p ≥ 0.183).

Effect of Package Material and Pre-Storage Treatments on Viabilty of wheat Seed

This research was conducted at Sakha Agric. Exp Station, Seed Technology Research Department, Field Crops ResearchInstitute, ARC, Giza, Egypt, during the period between 2018 and 2019 seasons, to evaluate the effect of packaging materials and pre-storage treatments on viability of wheat seed. The experimental design was a split- plot design with four replications. Seed samples were treated with malathion, phosphine, ficus powder and extract, clove powder and extract, camphor powder and extract and cupper nano -particles powder. Treated seeds were stored under open storage conditions for six months in Jute, Plastic and Polyethylene packages. The results revealed that, the type of package and treatments could provide special protection against seed deterioration namely; seed germination and seedling characters. The malathion and phosphine treatments could save the stored seed from the damage caused by insects, while cupper nano- particles treatment had a positive effect of controlling seed deterioration (germination capacity and seedling vigor). On the other hand, an experiment including similar treatments of the current research might be done to examine deteriorations which might take place to seeds stored for longer time (18 month).

Passport data and valorisation data of 33 accessions from the collection of genetic resources of the species Linum usitatissimum L.

Summary Introduction: In 2020, the Institute of Natural Fibres and Medicinal Plants (INF&MP) implemented the contract No. 7/PW 1.2 – IWNiRZ Poznań/KCRZG/2020 for the performance of a research service under the long-term programme “Creating scientific foundations for biological progress and protection of plant genetic resources as a source of innovation and support for sustainable agriculture and safety food for country”. Objective: The aim of the research was to prepare passport and valorisation data for 33 accessions of flax (Linum usitatissimum L.) sown at the INF&MP Experimental Station in Pętkowo. Methods: The field experiment was conducted on 33 samples of flax seeds, which were sown on an area of 1.6 m2. Morphological features were presented by means of numerical data and their evaluation. The agricultural characteristics (numerical values and percentage of the collective pattern) and lengths of vegetation period were also presented. The evaluation of the performed characteristics of flax accessions was presented numerically and the data were given to the International Flax Database. Results: On the basis of paper documentation, the country of origin of the accessions, the type of genotypes by origin (landrace, variety) and the date of inclusion of the accessions in the flax collection were determined. The results of the characterization of morphological trials were as follows: the total plant length of the flax plants ranged from 51.4 cm (La Estanzuella 117) to 76.5 cm (WUKR 06-417) According to the methodology of the International Flax Database, the total plant length were short (28 accessions), medium short (3) and medium (1). Technical length was usually short (28 accessions) and medium short (4 accessions). Stem thickness for all accessions was medium: 1.6–2.5 mm. The length of the panicle was long only for the Opal variety, for 25 accessions - medium and short for 6 accessions. A number of bolls from panicle was: 9.1–30.8. The 1000 seed weight was low for 25 accessions of flax and very low for 8 genotypes of flax. Conclusions: Both studied vegetation periods were short in the following flax accessions: AC Linora, Manchwrian, Noralta and T-397. Flax genotype WUKR-846 (I2010/0031) should be deleted from the flax genetic resources collection and considered as worthless as breeding material. The WUKR 06-417 accession collected during the field expedition is distinguished by a high fibre content – 27%. The highest seed yield per plot was obtained from the cultivation of the following linseed flax cultivars: Redwood, AC Mc Duff, Norlin, Noralta and Jenny.

INVESTIGATION OF CHANGING PHYTIC ACID IN LEGUMINOUS SEEDS DEPENDING ON SOAKING AND SPROUTING CONDITIONS

The results of studying changes of phytic acid in seeds of soya of “Diamond” variety and ones of chick-pea of “Krasnokutsky – 195” depending on seed soaking and sprouting conditions are presented. The content of phytic acid and changes of phytic globoloids in native soya and chick-pea seeds, sprouted in water, sprouted in the solution of mineral salts, preliminarily washed by the solution of lemon acid (C6Н8О7) were studied. The research topicality is conditioned by the necessity to develop food technologies using vegetable protein, which agent is soya and chick-pea, and to develop technological methods, favoring phytic acid inactivation. As a result of the study, it has been established, that a decrease of the phytic acid content in soya and chick-pea seeds is influenced by the sprouting process, and seeds washing by C6Н8О7 solution (pH – 3.5) is a catalyst of these processes. Soya seeds, sprouted in the potassium iodide solution (PI), and chick-pea seeds, sprouted in the sodium hydroselenite (NaHSeO3), preliminarily washed by C6Н8О7 solution (pH – 3.5), have less content of phytic acid, comparing with other samples. The phytic acid content decrease has been proved by a phytic globoloid decrease. It has been established, that the least diameter of a phytic globoloid is inherent to samples of soya, sprouted in PI solution and washed by C6Н8О7 solution (pH – 3.5), – 3.2 mcm, and a sample of chick-pea seeds, sprouted in NaHSeO3 solution, washed by C6Н8О7 solution (pH – 3.5) – 3.0 mcm. An undesirable “pea” smell also disappears. The established regularities are important for scientists because they allow to widen the assortment of products with vegetable protein, safe for the human organism

The features designed of mechatronic system of adaptive hopper’s feeder: case study for Scots pine seeds morphometry

This article will be of interest to engineers involved in designing devices for improving the quality of forest seeds. From the point of view of automated processing, in order to obtain a quality seedling, the seed of the Scots pine must be conditioned, that is, properly graded, and have sufficient ability to germinate in the field, that is, properly sown. It is based on studies of the movement of a single pine seed in the mechanical system of an optoelectronic separator. The experiment was established by measuring the geometric dimensions of samples (n = 500) from a representative sample of a seedlot. The Pinus sylvestris L. seeds were collected in the Pavlovsky district of the Voronezh region in autumn 2019. Seed samples were measured using a microscope in three mutually perpendicular directions. Seed samples asymmetric shape and an adaptive hopper’s feeder were modeled using SolidWorks software. Our results point to an important feature in the design of loading bins-the need to approximate the complex shape of a single seed of Scots pine with an asymmetric ellipsoid. The need for discrete seed feeding with a frequency no faster than 10−3-10−2 s is established to improve both the separation process.

The Effect of Seed Source and Post-harvest Practices on Quality of Soybean (Glycine max) Seeds in Busia County

Majority of farmers growing legumes use and recycle seeds from informal sources for the next crop. The quality of such seeds is unknown and usually leads to accumulation of pest, diseases and reduced yields. This study was carried out to determine production practices and quality of soybean seeds obtained from informal sources in Busia County. A survey was conducted to collect information on source of soybean seeds, production and post-harvest handling practices. Seed samples were collected from farmers, local market and agro-dealers. The seeds were evaluated for purity, seed coat damage, germination, vigour and fungal infection. Majority (48%) of farmers in Busia County used farm saved seeds, 29% and 23% used seeds from community based organizations and local markets, respectively. Most of the farmers (92%) used inappropriate threshing techniques like beating with sticks and about 80% of the farmers did not treat seed either before storage or during planting. Majority (68%) stored soybean for three months only. Seeds from informal sources had low purity, higher seed coat damage and infection as compared to certified seeds. The physical purity of seeds from the informal sources did not meet the recommended standard of 98% however their germination was comparable to 75% germination standard. Farmers therefore, should be advised to adopt use of certified seeds and appropriate handling techniques. Keywords: Soybean, seed source, seed quality, seed production practices

Exploring aflatoxin contamination and household-level exposure risk in diverse Indian food systems.

The present study sought to identify household risk factors associated with aflatoxin contamination within and across diverse Indian food systems and to evaluate their utility in risk modeling. Samples (n = 595) of cereals, pulses, and oil seeds were collected from 160 households across four diverse districts of India and analyzed for aflatoxin B1 using enzyme-linked immunosorbent assay (ELISA). Demographic information, food and cropping systems, food management behaviors, and storage environments were profiled for each household. An aflatoxin detection risk index was developed based on household-level features and validated using a repeated 5-fold cross-validation approach. Across districts, between 30–80% of households yielded at least one contaminated sample. Aflatoxin B1 detection rates and mean contamination levels were highest in groundnut and maize, respectively, and lower in other crops. Landholding had a positive univariate effect on household aflatoxin detection, while storage conditions, product source, and the number of protective behaviors used by households did not show significant effects. Presence of groundnut, post-harvest grain washing, use of sack-based storage systems, and cultivation status (farming or non-farming) were identified as the most contributive variables in stepwise logistic regression and were used to generate a household-level risk index. The index had moderate classification accuracy (68% sensitivity and 62% specificity) and significantly correlated with village-wise aflatoxin detection rates. Spatial analysis revealed utility of the index for identifying at-risk localities and households. This study identified several key features associated with aflatoxin contamination in Indian food systems and demonstrated that household characteristics are substantially predictive of aflatoxin risk.

Determination of 2,4-Dichlorophenoxyacetic Acid in Water and Edible Seeds Samples Using Salt-Assisted Liquid-Liquid Extraction Coupled with High-Performance Liquid Chromatography

A simple, fast, and effective salt-assisted liquid-liquid extraction (SALLE) technique coupled with high-performance liquid chromatography (HPLC) was developed for determination of 2,4-dichlorophenoxyacetic acid (2,4-D) in water and edible seeds samples. Due to the polar nature of the 2,4-D molecules, LC analysis was performed on a CN stationary phase by using acetonitrile and acidic water as mobile phase. Extraction was achieved based on salting-out phenomenon. Affecting variables on the extraction efficiency of the 2,4-D, such as the solvent type and its volume, type of salt and its concentration, vortex time, and sample pH, have been investigated and optimized. The target analyte was successfully extracted by acetonitrile and sodium chloride as extracting solvent and salting-out agent, respectively. Under the optimized experimental conditions, calibration curve shows good linearity (r2 > 0.9957) and precision (RSD < 6.5%) in the concentration ranges of 1.0–10,000 ng/mL. The limit of detection (LOD) and limit of quantification (LOQ) were 0.3 and 1.0 ng/mL, respectively. The recoveries were in the range of 82.0–95.0 % with RSD values less than 7.2%. The method was successfully applied for the extraction and determination of 2,4-D in several edible seeds and water samples.

Armazenamento de sementes e concentrações de ágar no cultivo in vitro de Brassavola tuberculata Hook. (Orchidaceae)

In vitro sowing and seed banks contributes to the conservation of the genetic variability of the orchids. Aimed to evaluate the storage time and agar concentrations on the in vitro germination of Brassavola tuberculata Hook. Seed samples were dried for 14 days and stored for 0, 30, 60 and 90 days under 4±2 oC. The culture medium was ½ MS, supplemented with agar (0; 1; 2; 3; 4; 5; 6; 7 or 8 g L-1). At 30 days after sowing the germination percentage was evaluated and the data were submitted for analysis of variance. The B. tuberculata seeds germinated at all concentrations of agar and storage periods evaluated, presenting average germination above 70%. Germination percentage decreases with increasing storage period and agar concentrations. Thus, for in vitro sowing of this species, seeds stored for up to 30 days are recommended, regardless of the agar concentration used in the culture medium.

Seed Germination and Initial Growth of Pepper Seedlings is Influenced by Environment Temperature and Priming Method

The effects of different environment temperatures, priming treatments and priming durations on germination parameters and early growth of pepper seedlings were investigated. Seeds were hydro primed in distilled water, or osmo primed in two different water potentials (-0.15 and -0.5 MPa) of polyethylene glycol (PEG) 8000. Both, hydro primed and osmo primed seeds were subject of two different imbibitions periods, 48 and 72 hrs. In addition to primed seeds, an equal sample of non primed seeds was included in the experiment as a control variant. Following priming, the seeds were subjected to germination tests at two different environment temperatures, respectively 18 0C and 24 0C. In general, there was no significant effect of hydro priming on germination parameters or early growth of pepper seedlings. On the contrary, significantly higher germination percentage and germination speed and significantly shorter mean germination time than the non primed seeds were obtained due to seed osmo priming by PEG. Similarly, an enhanced seedling growth, especially under suboptimum temperature conditions was evidenced in PEG primed seedlings. Apart from germination speed, the increase of PEG concentration from -0.15 to -0.5 MPa had no effect to germination parameters of pepper seeds. The extent of the imbibitions period over 48 hrs did also have no benefits on germination parameters.

Effect of Harvesting Stages and Nitrogen on Seed Quality and Yield of Jute Mallow (Corchorus olitorius L.)

Production of high quality seeds in African leafy vegetables has not been practiced due to varying reasons including incorrect harvesting stages and fertilizer rates. Jute mallow (Corchorus olitorius L.) pods do not ripen simultaneously and fruits left to dry on mother plant long before harvesting, which face seed quality deterioration. Timely seed harvesting ensures maximum seed quality attributes of purity, germination and vigour. The present study aimed to investigate the effects of harvesting stages and nitrogen fertilizer on seed quality and yield of Jute mallow. Seed samples from four Jute mallow morphotypes (GEMS, GLMT, BEMS, and BLMT) were planted. Completely randomized block design was used for analysing the effects of nitrogen fertilizer levels (0, 60 and 120 kg/ha) with three replicates. Five plants were randomly tagged per plot and seed harvested at three maturity stages of green, tan and black. Seed quality test of purity, germination and vigour were done as per ISTA (2004) and means separation done by DMRT at p≤0.05. Results showed that harvesting stage significantly influenced seed quality attributes, in a way that the maximum purity, germination and seed vigour was detected at tan pod stage and their lowest levels were observed at black pod stage. It can be concluded that best agronomic practices of Jute mallow seed can be attained when they harvested at tan stage together with use of N fertilizer for high seed quality and yield.

IMPROVING YIELD AND SEEDS IN OKRA CROP THROUGH INDUCED USEFUL MUTATIONS

Cultivation of okra in Egypt is challenged by low yield due to lack of improved cultivars. Gamma irradiated okra seeds can generate genetic variability to improve the crop. Field experiment was carried out in a private farm at Sidy salim distrect, Kafr El-Sheikh Governorate, Egypt during 2017, 2018 and 2019 seasons. Samples of dry seeds each of two okra cultivars Balady and Sabahia were irradiated with different doses of gamma rays (0, 10, 20, 30 and 40 KR) and variability in growth characteristics, earliness and pod yield were investigated in M1, M2 and M3 generations. Data were statistically analyzed for all the levels of significance. For significant F ratios New Duncan's Multiple Range (DMRT). The results of this investigation showed that the M1 plants exhibited different degrees of reduction in growth in comparison with those of the untreated control plants. In M2-generation, 26 different mutant lines were selected. Analysis of variance in M3 generation showed a highly significant difference among M3 lines and control for vegetative and agronomical traits of two okra cultivars. Among 26 M3 lines, one mutant line was produced higher pod yield (29.4 g/plant) compared with control plants (14.6 g/plant). This line will be being to evaluated for the desired traits and wide adaptability to biotic and abiotic stress to obtain new variety with high yield and good quality. Conclusively, Induced mutation is a valuable breeding tool for inducing new genetic recombination and selectsuseful lines with desired traits in okra. The present study made an extensive phenotypic evaluation from M1 to M3 generations which enabled us to select promising mutant lines with higher pods yield in M3generation. These lines could be valuable genetic resources for genetic improvement and breeding of okra in Egypt. Further selection and improvement are needed for testing mutant lines for adaptability and stability under different environments under large-scale production for releasing new improved okra cultivars.

Обработка некондиционных семян сосны Банкса (Pinus banksiana Lamb.) и сосны обыкновенной (Pinus sylvestris L.) низкочастотным электромагнитным полем

This paper presents the results of a study that was conducted in the laboratory of the LT1 Department of the Moscow state technical University. N.E. Bauman in December 2017. The aim of the study was to study the effect of a low-frequency electromagnetic field (EMF) on the germination of substandard seeds of banksa pine (Pinus banksiana Lamb.) and common pine (Pinus sylvestris L.). Two samples of banksa pine seeds that differ in their initial germination (2008 and 2010 collection) and one sample of common pine seeds (2012 collection) were selected for the study. Laboratory studies included 3 experiments, each in 3-fold repetition. Treatment experienced of the seeds of low-frequency EMFs was performed using a low frequency generator «Growth-Active» technology POSEP (pre-sowing seed treatment with electromagnetic field), served as control untreated seeds. To determine the germination energy, the seeds were sprouted in the laboratory on a special plant (Jacobsen’s table), with a constant water temperature of 24° C (according to GOST 13056.6–97). The results of the laboratory tests showed a high effectiveness of seed treatment technology POSEP, it can be regarded as a promising way to reveal the physiological potential of seeds of coniferous species, and it is bound to affect the quality of planting material.

Patterns of genetic variation in leading-edge populations of Quercus robur: genetic patchiness due to family clusters

The genetic structure of populations at the edge of species distribution is important for species adaptation to environmental changes. Small populations may experience non-random mating and differentiation due to genetic drift but larger populations, too, may have low effective size, e.g., due to the within-population structure. We studied spatial population structure of pedunculate oak, Quercus robur, at the northern edge of the species’ global distribution, where oak populations are experiencing rapid climatic and anthropogenic changes. Using 12 microsatellite markers, we analyzed genetic differentiation of seven small to medium size populations (census sizes 57–305 reproducing trees) and four populations for within-population genetic structures. Genetic differentiation among seven populations was low (Fst = 0.07). We found a strong spatial genetic structure in each of the four populations. Spatial autocorrelation was significant in all populations and its intensity (Sp) was higher than those reported in more southern oak populations. Significant genetic patchiness was revealed by Bayesian structuring and a high amount of spatially aggregated full and half sibs was detected by sibship reconstruction. Meta-analysis of isoenzyme and SSR data extracted from the (GD)2 database suggested northwards decreasing trend in the expected heterozygosity and an effective number of alleles, thus supporting the central-marginal hypothesis in oak populations. We suggest that the fragmented distribution and location of Finnish pedunculate oak populations at the species’ northern margin facilitate the formation of within-population genetic structures. Information on the existence of spatial genetic structures can help conservation managers to design gene conservation activities and to avoid too strong family structures in the sampling of seeds and cuttings for afforestation and tree improvement purposes.

Drying and physiological quality of palheteira seeds (Clitoria fairchildiana R.A. Howard)

Knowledge about seed storage behavior is important to preserve plant species. Clitoria fairchildiana R.A.Howard is an endemic species with medicinal properties, it is used in the recovery of degraded land. The objective of this study is to evaluate the effect of drying on the physiological quality of C. fairchildiana seeds. Seeds were oven dried along with silica gel for 18 days and in intervals of 2 or 3 days, samples were removed to assess the seed moisture content. This was done in an oven at 105±3 oC for 24h, using four replicates with 10 seeds each. After undergoing the above-mentioned treatment, a sample of seeds was stored in the freezer (-18 ºC) for 3 months. Sowing was carried out in plastic trays in a sand and sawdust mixture (1:1), previously sterilized in hot water (100 oC) for two hours. Seeds were left to germinate in a laboratory with no temperature and relative humidity control. Germination tests were performed over 14 days with daily counts of the number of emerged seedlings. The percentage of seed germination, abnormal seedlings and dead seeds were obtained 14 days after sowing. The experimental design was completely randomized with four replications of 25 seeds. The reduction of seed moisture content from 18.5% to 5.6% affected physiological seed quality causing a reduction in the germination percentage and an increase in dead seeds and abnormal seedling percentage. C. fairchildiana seeds are classified as intermediate and they can be desiccated up to 8.6% with no reduction in physiology quality.