Ash Seeds Research Articles

Procjena vitaliteta svježeg i preležalog sjemena poljskog jasena (Fraxinus angustifolia Vahl)

U radu se uspoređuje vitalitet svježe sakupljenog i preležalog sjemena poljskog jasena kao jedne od glavnih vrsta drveća u posavskim nizinskim šumama i nama zanimljive zbog brzine rasta, kratke ophodnje, u usporedbi sa hrastom lužnjakom te tehničke vrijednosti drva. Sjeme vrsta roda Fraxinus spp. često ima perikarp koji je nepropustan za kisik, metaboličke inhibitore u endospermu i embrijima, nedozrele embrije ili nedostatak tvari koje potiču rast u embrijima. Dormantnost sjemena najčešće se savladava toplo-vlažnim i hladno vlažnim postupkom. Sjeme je sakupljano je u G. J. Josip Kozarac kojim gospodari šumarija Lipovljani. Procjena vitaliteta sjemena koje je najranije sakupljeno (21. 08.) obavljena je topografskom metodom tetrazola i u skladu s ISTA pravilima. Sjeme poljskog jasena (urod 2013.) u rasadniku Brestje stavljeno je na stratifikaciju na otvorenom 16. 1. 2015. godine, a sijano 21. 3. 2015. godine. Stratifikacija je trajala 64 dana. Preležalo sjeme poljskog jasena sakupljeno je 20.10.2015. godine. Procjena vitaliteta obavljena je istom metodologijom kao u slučaju svježeg sjemena. Svježe sjeme imalo je vitalitet od 91 %. Nevitalnog sjemena bilo je 9 %, od čega najveći postotak otpada na šturo sjeme (5 %), slijedi insektima oštećeno sjeme (3 %) i sjeme kod kojega je embrio i endosperm imao neobojene površine ili nekroze. Preležalo sjeme imalo je vitalitet od 87%. Nevitalnog sjemena bilo je 13 %, od čega najveći postotak otpada na sjeme kod kojega je embrio s neobojenim površinama ili nekrozama, a endosperm potpuno obojen (10 %). Sjemena kod kojega je embrio i endosperm s neobojenim površinama ili nekrozama bilo je 3 %. Od nevitalnog preležalog sjemena utvrđeno je kako najprije dolazi do razvoja nekroza ili truleži na embriju, a zatim se ona širi na endosperm. Od nekroza ili truleži na embriju primijećene su one s potpunom nekrozom, nekrozom kotiledona, hipokotila i plumule, hipokotila i radikule i samo radikule. Bez obzira na vitalitet od 82%, rasadnička klijavost sjemena u proljeće 2015. godine u rasadniku Brestje iznosila je 0%. Utvrđena je statistički značajna razlika između vitaliteta svježeg i preležalog sjemena. Preležalo sjeme imalo je za 4 % manji vitalitet od svježeg sjemena. Na osnovi ovih istraživanja može se preporučiti početak sakupljanja sjemena poljskog jasena od druge polovice mjeseca kolovoza, jer takvo sjeme pokazuje visoki vitalitet. Kod sjetve sjemena u rasadniku treba voditi brigu o njegovoj starosti, predsjetvenoj pripremi i vremenu sjetve. Preporuka je za buduću rasadničku proizvodnju sadnica poljskog jasena generativnim načinom utvrditi optimalnu vrstu i trajanje stratifikacije sjemena s obzirom na mikroreljefne različitosti rasta matičnih stabala s kojih je sakupljano sjeme (bara, niza, greda), klimu i sjemensku rajonizaciju.

Effect of dietary prickly ash (Zanthoxylum bungeanum) seeds (PAS) on growth, body composition, and health of juvenile Jian carp (Cyprinus carpio var. Jian)

Prickly ash seed (PAS) is composed of 27–31 % lipids and may be a potential lipid-rich ingredient for fish feed. In this study, we examined how the supplementation of four isonitrogenous (31.44 %) and isocaloric (16.5 kJ g−1) experimental diets (soybean meal, cotton meal, and rapeseed meal were the primary protein sources; soybean oil was the main lipid source) with various concentrations of PAS (0.0, 2.5, 5.0, and 7.5 %) affected the growth, body composition, and health status of Jian carp (Cyprinus carpio var. Jian). A total of 252 fish (44.38 ± 3.05 g) were randomly distributed into 12 circular tanks (21 fish/tank) and hand-fed one of the four diets three times daily to apparent satiation. The fish were sampled after consuming the diets for 60 days. The results showed that final weight (121.74–101.32 g) and specific growth rate (1.67–1.34) decreased as PAS increased, but only the 7.5 % PAS diet negatively influenced the growth and feed conversion ratio of the experimental fish (P 0.05) but increased the levels of eicosapentaenoic acid (20:5n-3) and docosahexaenoic acid (22:6n-3) in the muscle and hepatopancreas. PAS had no adverse effect on serum biochemical parameters, including the activities of alanine aminotransferase (18.87–24.90 U L−1) and aspartate aminotransferase (117.13–129.94 U L−1) and the concentration of total protein (23.63–27.13 g L−1), albumin (9.08–9.90 g L−1), globulin (14.17–17.23 g L−1), glucose (4.77–6.30 mmol L−1), total cholesterol (2.32–2.81 mmol L−1), triglyceride (2.25–2.52 mmol L−1), high-density lipoprotein cholesterol (0.41–0.43 mmol L−1), and low-density lipoprotein cholesterol (0.57–0.76 mmol L−1) (P > 0.05). No significant difference in hepatopancreatic superoxide dismutase activity (101.5–107.2 U mg prot−1) was found among the groups (P > 0.05). However, malondialdehyde content increased with increased dietary PAS supplementation, with fish in the 5.0 and 7.5 % PAS groups showing levels significantly higher than those in the other groups (P < 0.05). Fish fed the 7.5 % PAS diet had a midgut fold height (358.76 μm) and fold width (71.48 μm) that was significantly lower than those of fish in the other groups (456.48–610.13 and 93.25–106.83 μm, respectively; P < 0.05). The results of the study suggest that the diet for Jian carp can be supplemented with up to 5.0 % PAS without adverse effects on growth performance and health status.

Forest seed treatment with brassinosteroids to increase their germination under stress conditions

The effect of different concentrations of brassinosteroids (1:10, 1:100, 1:210) on the germination of sycamore ( Acer pseudoplatanus L.) and ash ( Fraxinus excelsior L.) seeds was investigated in stress conditions. The product Lexin (a mixture of humic acid, fulvic acid and auxin), which also supports seed germination, was selected as a reference treatment. The results show that the most effective is the lowest concentration of brassinosteroids which gave nearly the same effect as the reference product Lexin. The data also suggest the positive effect of pretreatment of sycamore and ash seed in pure water both on germination and germination energy.

Gibberellin-like substances and growth inhibitors in relation to the dormancy and after-ripening of ash seeds (Fraxinus excelsior L.)

Gibberellin-like substances and growth inhibitors in relation to the dormancy and after-ripening of ash seeds (Fraxinus excelsior L.)

A Volatile Lactone of Hymenoscyphus pseudoalbidus, Pathogen of European Ash Dieback, Inhibits Host Germination

The largely unknown secondary metabolism of the plant pathogenic fungus Hymenoscyphus pseudoalbidus was investigated by use of the CLSA method. A set of volatile lactones was identified by GC/MS. The lactones were synthesized and used in bioassays in which one of the compounds was found to be a strong germination inhibitor for ash seeds, causing necroses in the plant tissue.

Ash (Fraxinus spp.) mortality, regeneration, and seed bank dynamics in mixed hardwood forests following invasion by emerald ash borer (Agrilus planipennis)

Emerald ash borer (EAB; Agrilus planipennis) has killed millions of ash trees and threatens ash throughout North America, and long-term persistence of ash will depend on the potential for regeneration. We quantified ash demography, including mortality and regeneration, of Fraxinus americana (white ash), Fraxinus pennsylvanica (green ash), and Fraxinus nigra (black ash) in mixed hardwood forests near the epicenter of the EAB invasion in southeastern Michigan and throughout Ohio. Plots were established across a gradient of ash densities. Ash was the most important species in hydric sites, and ranked second among all species in mesic and xeric sites. In sites nearest the epicenter in Michigan, ash mortality exceeded 99 % by 2009, and few or no newly germinated ash seedlings were observed, leaving only an “orphaned cohort” of established ash seedlings and saplings. As ash mortality increased, the number of viable ash seeds in soil samples decreased sharply, and no viable seeds were collected in 2007 or 2008. In Ohio sites farther from the epicenter, densities of new ash seedlings were much higher in plots with healthy ash trees compared to plots where trees had died. EAB was still present in low densities in Michigan and Ohio stands in 2012 where average mortality of ash was nearly 100 %. The future of ash at these sites will depend on the outcome of the dynamic interaction between the orphaned cohort of previously established ash seedlings and saplings and low density EAB populations.

Effects of KNO3 pretreatment and temperature on seed germination of Sorbus pohuashanensis

We characterized the effects of KNO3 pretreatment and germination temperature on dormancy breaking and germination of mature mountain ash seeds. Seeds treated with KNO3 and germinated at 25 °C followed by 5 °C had significantly higher germination percentages and germination potentials (51% and 49%, respectively), compared with controls. These treated seeds also exhibited reduced germination initiation times (minimum of 48 days), and elevated germination rate indices (up to 97). The germination of seeds subjected to long-term cold storage (2 years at 0–5 °C) was also significantly improved by 3 days of 4% KNO3 pretreatment before germinating under a variable temperature regimen (5 °C followed by 25 °C, and followed by 5 °C). Germination percentages and germination potentials for these cold-stored seeds reached 67% and 54%, respectively, and the germination rate index increased to 126.99. Pretreatment of mountain ash seeds with KNO3 represents a practical, effective, and pollution-free method for improving germination, and can be implemented easily within a variety of nursery settings.

Farm Boundaries as Agroecological Systems

South-central Pennsylvania, framed by the great folds of the Appalachians to the north and west, by the Mason-Dixon Line to the south, and by the rise of hills that bound the lower Susquehanna River to the east, was claimed by settler-farmers of western European descent during the early and mid-eighteenth century. They utilized river and stream valleys to gain access to the fertile lowlands and rich uplands of the region, following in the steps of surveyors to mark farm boundaries with timber fences cut from the cloak of forest. The social and ecological imprint of these boundary structures has endured for hundreds of years.

Ash ( Fraxinus excelsior ) seed quality in relation to seed deterioration under accelerated aging conditions

This study was conducted to evaluate the response of ash ( Fraxinus excelsior ) seeds under accelerated aging test. The accelerated aging test was carried out at three different temperatures: 41, 43 and 45°C with four duration periods of 48, 72, 96, 144 and a relative humidity of 100%. The two seed lots of F. excelsior were subjected to tests of their quality including standard germination, vigor index, seedling growth and seedling dry weight. A completely randomized factorial design with four replications was used. Results indicated that, old seeds were more sensitive to accelerated aging than new seeds. Seeds of both lots had a reduction of viability and vigor after accelerated aging at 41°C for 96 h, 43 and 45°C for 72 to 144 h. Germination, vigor index, seedling growth and seedling dry weight showed a greater response to accelerated aging. Key words : Fraxinus excelsior, accelerated aging, germination, seed vigor, seedling growth rates.

The Ultrasonic Extraction of Oil from Prickly Ash (&lt;i&gt;Zanthorylum bungeanum maxim&lt;/i&gt;) and its Composition Analysis

The ultrasonic assistance extraction technology of the prickly ash oil from prickly ash seeds was studied, and the effects of extraction medium, temperature, time and rate of liquid to solid was discussed. Meanwhile, chemical compositions of prickly ash oil extarcted from its seeds and shell were analyzed by gas chromatography-mass spectrometry (GC-MS) respectively. The results showed that the extraction rate of prickly ash oil is 7.8% by using 95% ethanol as extractant with a ratio ethanol/ash (v/w) of 3:1 (mL/g) and extracting at 60 °C for 90 min. Heat treatment of prickly ash, however, led to a lower rate under the corresponding conditions. The chemical compositions of both oils are very different with alkenes from seeds and with carboxylic acids together with its esters from shell.

Effect of long-phase stratification treatments on seed germination in ash

Ash (Fraxinus excelsior L.) seeds require warm treatment followed by cold treatment to release dormancy and this is most effective if carried out in a medium. The objective of this study was to determine if long periods of warm treatment would enhance germination at 15 (8-h light)/5°C (dark) and 15°C (same lighting conditions) in ash seeds of north-western European origin. Ash seeds were fully imbibed (57% moisture content (MC)) or adjusted to 45% MC either in a medium or without a medium for 10–30 weeks of warm treatment, followed by 10, 20 or 30 weeks of chilling. Germination increased at both germination temperature regimes as the duration of warm treatment increased up to 18 (with medium) or 20–30 (without medium) weeks, well after the embryo had completed development (14 weeks). The response to 20 or 30 weeks of chilling was better than that of 10 weeks of chilling, but the impact of chilling was smaller than that of warm treatment. Seed MC did not significantly affect germination, but it reduced mould growth. A long warm treatment (followed by cold treatment) without a medium is the recommended treatment for ash seeds.

Cryopreservation of dormant European ash (Fraxinus excelsior) orthodox seeds

We investigated the sensitivity of dormant Polish-provenance Fraxinus excelsior L. seeds to extreme desiccation and liquid nitrogen (LN, -196 degrees C). Germination and seedling emergence tests revealed that the critical water content (WC) of the desiccated seeds was 0.04-0.06 g H(2)O g(-1) dry mass, g g(-1) (0.04 g g(-1) in the germination test and 0.06 g g(-1) in the seedling emergence test). The seeds that were within the safe WC range (0.06-0.24 g g(-1) in the germination test and 0.08-0.24 g g(-1) in the seedling emergence test) tolerated freezing in LN. A 2-year seed storage period in LN after desiccation to a safe WC did not decrease the germination after thawing as compared with a 2-year seed storage at -3 degrees C. When the seeds were stored in LN after dormancy breaking, the germination rate after storage was lower, because the seeds had to be desiccated to the lower level (~ 0.11 g g(-1)) within the seeds' safe WC range after stratification (before storage). Secondary dormancy was induced in seeds that were desiccated after stratification. The results of this study confirm the feasibility of long-term cryopreservation of European ash seeds in forest gene banks.

Comparative habitat susceptibility to invasion by Chinese ash (Fraxinus chinensis: Oleaceae) in a tropical Andean landscape

Chinese ash (Fraxinus chinensis) is an exotic tree species that has been used in non-commercial monospecific plantations for revegetation programs in the Central Andes of Colombia. At the Otun river watershed, these plantations occur in patches intermixed with old pastures, oak forests, and successional forests. In this heterogeneous landscape, the ash has been able to invade some of its surrounding habitats. This study evaluates the invasion patterns of ash to each of these habitats and experimentally quantifies seed and seedling survivorship and seedling growth as three processes that could determine ash establishment. Of the four habitats examined, old pastures were the most vulnerable to invasion, followed by oak plantations, and successional forest. Ash plantations exhibited recruitment levels intermediate between pastures and oak plantations. Abandoned pastures showed the highest seed germination, seedling survivorship, and seedling growth. In the ash plantations, recruitment seemed negatively affected by the low number of germinated seeds, high mortality of seedlings, and low growth. Invasion in oak plantations was constrained by high seed mortality and burial of seedlings by leaf litter, although the seedlings that did survive grew fast and produced a high number of leaves. Within the successional forest, Chinese ash seeds germinated but establishment was constrained by a reduced seedling survivorship and low growth. This research offers new evidence of how different processes affecting the establishment of an invader may differ among landscape elements, and it also yields important information for the management and control of ash in these Andean landscapes.

Performance of Green Ash Seed Sources at Four Locations in the Great Plains Region

Abstract Green ash trees from 10 seed sources were planted in a test in 1961 in four states of the Great Plains Region. After more than 20 years, height growth indicates a strong interaction between seed source and plantation location. Larger trees were from southerly sources within about three degrees of latitude of the plantation site. Beyond those limits, cold injury may result. Height and dbh age-age correlations were highly significant at 8 and 20+ years. Height and dbh correlated negatively with a decrease in latitude. North. J. Appl. For. 22(1):54–58.

Six chemicals with animal repellent or insecticide properties are screened for phytotoxic effects on the germination and viability of ash, birch, Corsican pine and sycamore seeds

Summary As a prelude to direct sowing experiments, a laboratory study was carried out to determine whether six chemicals with insect and/or rodent repellent properties (Aaprotect, Capsaicin, Guardsman, Hallmark, Scuttle, Treeguard) affected the germination capacities and/or viability percentages of European ash (Fraxinus excelsior L.), silver birch (Betula pendula L.), Corsican pine (Pinus nigra ssp. laricio L.) and sycamore (Acer pseudoplatanus L.) seeds. None of the chemical repellents had a significant effect on either the germination capacity or viability of ash or birch seeds. One repellent (Guardsman) significantly reduced the germination capacity of sycamore from 49 to 32 per cent (P ≤ 0.01). Two repellents (Aaprotect and Scuttle) significantly reduced the germination capacity of Corsican pine from 74 to 62 per cent (P ≤ 0.05) and 11 per cent (P ≤ 0.001), respectively. Corsican pine was therefore the most sensitive of the species investigated to phytotoxic effects. Viability percentages (at the end of germination tests on repellent-treated seeds) showed that virtually all ungerminated seeds were dead. Greater phytotoxicity was observed for small-seeded species when they were incubated on a substrate of moist filter paper than when they were sown in moist peat + sand. One explanation is that the larger volume of peat + sand in the seed-tray allowed the chemicals to leach away from the seeds more quickly. Alternatively, perhaps the peat inactivated the chemicals through adsorption. The results are used to exclude certain chemical and tree seed combinations from future seed predation studies associated with direct sowing.

Identification of abscisic acid, indole-3-acetic acid, jasmonic acid, indole-3-acetonitrile, methyl jasmonate and gibberellins in developing, dormant and stratified seeds of ash (Fraxinus excelsior)

Abscisic acid (ABA), indole-3-acetic acid (IAA), indole-3-acetonitrile(IAN), jasmonic acid (JA), methyl jasmonate (MeJA) and gibberellins (GAs);GA1, GA3, GA8, GA9,GA12,GA15, GA17, GA19, GA20,GA24, GA29, GA44, GA51 andGA53, were identified in seeds of ash (Fraxinusexcelsior L.) by combined gas chromatography–massspectrometry.The presence of ABA, IAA, IAN, JA and MeJA was confirmed in developing, dormantand stratified seeds by comparison of Kovat's retention indices (KRI) andspectral data with those obtained for standard compounds. Also, the presence ofGA1, GA3, GA9, GA19,GA20and GA44 was confirmed by comparison of KRI and spectral data withthose of standards, while the presence of the remaining GAs was confirmed bycomparison of KRI and spectral data with literature values. All of the GAsidentified were detected in extracts of developing seeds, while onlyGA17 and GA19 were detected in dormant seeds andGA1, GA8, GA19, GA20 andGA29 were detected in stratified seed. The results suggest it islikely that the GAs are important in development and in breaking dormancy ofashseed. While ABA, JA and MeJA may be important in control (i.e. onset andmaintenance) of dormancy. The roles of IAA and IAN are unclear, but it ispossible that they are important in the development of ash seed, and as part ofthe dormancy controlling mechanism.

Fluorescein diacetate as a viability stain for tree roots and seeds

Fluorescein diacetate (FDA) was tested as a viability stain for roots of green ash as well as for seeds of green ash and 10 other tree species. The viability level indicated by FDA staining of green ash roots agreed well with root growth potential results, bud condition assessment, and foliage browning measurements. In seed viability experiments, the FDA staining intensity of embryos was related to germination in 9 out of 11 species tested using a 30 minute stain incubation period. In the other 2 species, eastern hemlock and Scotch pine, embryo FDA staining intensity and germination were also similar, provided an 18 h stain incubation period was used. When two seedlots of differing viability were tested in each of white spruce, Douglas-fir, and pitch pine, significantly higher germination was reflected in significantly higher embryo FDA staining intensity. In Sitka spruce seed that was heat treated to produce a range of viabilities, the semilog plot of germination (log scale) and FDA staining intensity of the embryo (linear scale) had an r2= 0.95. Based on these preliminary results, FDA shows promise as a rapid viability stain for tree roots and seeds.

Improved Adventitious Shoot Production in White Ash

To increase adventitious shoot formation, we investigated the effects of the number of weeks on medium with high levels of plant growth regulators and seedcoat removal. Dissected white ash seeds were placed on a solidified MS medium containing 10 μM TDZ and 1 μM 2,4-D (shoot initiation medium). After 2, 3, or 4 weeks in vitro, explants were transferred to shoot elongation medium (3 μM TDZ, 1 μM BA, and 1 μM IBA). After 12 weeks, the greatest number (1.8) and longest shoots (18.7 mm) were in cultures incubated on the shoot formation medium for 3 weeks. In a separate experiment, dissected seeds were placed on shoot formation medium. Seedcoats were removed after 10 days in vitro. Explants were transferred to shoot elongation medium after 4 weeks in vitro. There were more shoots (2.5) on 12-week-old explants without seedcoats than on explants with seedcoats (0.9). This result may be related to inhibitors in the testa.

Gelling Agents Affect Adventitious Shoot Organogenesis in White Ash

Dissected white ash seeds were placed on an agar-solidified MS medium with 10 μM TDZ and 1 μM 2,4-D (shoot initiation medium). After 4 weeks, explants were transferred to shoot elongation medium (3 μM TDZ, 1 μM BA, and 1 μM IBA) solidified with 0.7% Sigma agar, 0.525% agar + 0.05% gelrite, 0.35% agar + 0.1% gelrite, 0.175% agar + 0.15% gelrite, 0.2% gelrite, or no gelling agent (liquid medium). After 12 weeks in vitro, shoot growth and number were suppressed in cultures containing 0.2% gelrite (9.3 mm and 0.7 shoots) and in cultures containing no gelling agent (6.9 mm and 0.7 shoots). There were no differences in shoot growth and number in cultures containing 0.7% Sigma agar (2.2 mm and 16.5 shoots), 0.525% agar + 0.05% gelrite (2.6 mm and 18.7 shoots), 0.35% agar + 0.1% gelrite (1.6 mm and 17.4 shoots), and 0.175% agar + 0.15% gelrite (2.0 mm and 20.4 shoots). The most vitrification occurred in cultures on medium with the lowest amount of agar, gelrite only, and liquid medium.

RESPONSE OF WOODY PLANTS TO KANAMYCIN AND BIALAPHOS

Resistance to kanamycin (kan) and bialaphos is commonly used to select for transgenic plants. To determine inhibitory levels for in vitro selection, nontransformed tissues of arabica coffee, white ash, black walnut, and Rhododendron `P.J.M. Hybrids' were incubated in media containing concentrations from 0 to 400 mg/liter kan or 0 to 25 mg/liter bialaphos. Callus from coffee leaf explants was completely inhibited by 100 mg/liter kan or 1 mg/liter bialaphos. Shoot organogenesis, callus and epicotyl growth from white ash seeds were inhibited by 20 mg/liter kan or 5 mg/liter bialaphos. Secondary embryogenesis from black walnut somatic embryos was mostly inhibited by 40 mg/liter kan and totally inhibited by 1 mg/liter bialaphos. Shoot organogenesis from rhododendron leaf explants was inhibited by 10 mg/liter kan or 10 mg/liter bialaphos.