Total Germination Research Articles

Optimizing Cereal Crop Performance with Nutrient Priming

The fundamental building blocks for the success of stand establishment for any crop plant are better germination and robust seedlings. Pre-treatment of the seeds is one of the best methods that may possibly improve germination and maintain the uniformity and stability of the seedlings. Primed seeds usually exhibit synchronized and early germination and sometimes greater total germination percentage over a range of environmental conditions. This enhancement has been linked to osmotic correction, metabolic repair during imbibition, and the accumulation of chemicals that promote germination. Nutri-priming is a good alternative to meet plant nutritional requirements. Seed priming with macro or micronutrient (nutripriming) application has been recently done on various agronomic crops including rice, maize and wheat; lead to better germination and establishment. It aims to combine the positive effects of hydro priming with the nutritional aspect of fertilizers. Crop seeds can be primed with either micro or macronutrients, which improves the nutrient content and increases the germination, sprouting, and water uptake efficiency. Primed seeds performed better under diverse environments especially under sub optimal conditions at sowing and resulted in higher yield compared to unprimed seeds. Priming requires specific temperature and time, if it is not followed then the seed can be deteriorated due to embryo protrusion. Due to readily available food during germination, primed seed are better able to complete the process of germination in a short time and cope with environmental stresses including low temperatures. In fact, it may be regarded as a useful method for enhancing crop establishment in regions with unfavourable agro-climatic conditions (rainfed, dry farming, and dry land farming) with increased yield, tolerance to stressful situations, resistance to diseases, crop competitiveness against weeds, and water use efficiency.

Assessing of sugar beet Seed adaptation under salt and drought stress conditions with coating technology based on Fuzzy inference system

Sustainability in crop production is highly dependent on favorable indicators of germination and seedling establishment. In this research seed coating different treatments data prepared and membership function defined in fuzzy inference system then used rule editor tool for determining parameters weight for achieved the best coating treatment in salinity and drought stress conditions. Seed coating formulations were investigated in laboratory and greenhouse experiments for their potential to increase maximum germination, germination rate, germination uniformity, and seedling growth of sugar beet seeds. Sugar beet seeds were coated with different compounds and combinations, including micro- (Fe, Zn, Cu, Mn, Co, Mo) and macro- (N, P, K) nutrients, humic acid, gibberellic acid, kaolin, and chitosan. Coated and non-coated sugar beet seeds were evaluated for germination and seedling growth after 10 and 21 days, respectively. In total, 30 different treatments were used to assess the effects of seed coating treatments. In laboratory experiments, sugar beet seeds were placed on paper in Petri dishes and maintained in a germinator at 25 °C. Sodium chloride and polyethylene glycol 8000 were used to apply salinity and drought stresses at three levels each and achieve the results of seed coatings on reducing the effects of salinity and drought stresses. To determine the indices related to emergence and establishment, cultivation trays were utilized with four replications for each treatment. The trays were kept inside a greenhouse. Coating treatments significantly improved total germination percentage, germination rate, seedling growth, and uniformity compared with the non-treated controls. In all treatments, polyvinylpyrrolidone was utilized as a binder. The best treatment with respect to germination and seedling growth indices was number 21 (micro and macronutrients, humic acid, gibberellic acid) in salinity and drought stress conditions. The results by fuzzy inference system illustrated that micronutrients, humic acid, and gibberellic acid create the best seed coating for sugar beet seeds, especially when combined at the specified amounts.

Effects of different loads of Pinus pinaster Ait. litter and ash on the germination and growth of Cistus ladanifer L

Key messageCistus ladanifer L. shows an extraordinary plasticity of germination and growth. Fire promotes the regeneration of C. ladanifer by triggering its germination through thermal shock as well as by enhancing its seedling growth through the addition of ashes. On the contrary, stacking of Pinus pinaster Ait. leaf litter may hinder seedling establishment, at least in the first months after germination.ContextPinus pinaster Ait. is affected by forest fires in the Mediterranean basin. Its extreme flammability is due to the high spatial continuity together with the massive accumulation of leaf litter. Cistus ladanifer L. is a species which is widely distributed in the west Mediterranean region where it can form vast shrublands and flourish under these pinewoods. Although high temperatures associated with the occurrence of fire trigger germination of C. ladanifer, knowledge on how other factors, such as the presence of litter on the forest floor or the ash left after the fire, influence germination and seedling growth is essential to improve land management plans.AimsThe main objective of this study was to determine the effects of different loads of litter from P. pinaster and ash from their combustion on the germination and growth of seedlings of C. ladanifer.MethodsTwo experiments were carried out to assess the effect of heat shock (100 °C for 10 min) and two loads of litter and ash from P. pinaster (control, high and low loads of litter, high and low loads of ash) on the germination and growth after 2 and 4 months of C. ladanifer.ResultsHeat shock significantly increased the germination of C. ladanifer. In contrast, the addition of litter and ash had no effect on total germination but affected the growth of the seedlings coming from seeds exposed to heat shock. Litter treatments reduced biomass of 2 months seedlings and ash increased biomass of 4 months seedlings.ConclusionC. ladanifer is a species favoured by fire in different ways depending on the stage of regeneration. Germination is promoted by heat shock while seedling growth is favoured by ash nutrients. In contrast, pine leaf litter hinders seedling growth, although this effect disappears 4 months after germination. Alternative forest management practices to prescribed fires are recommended if preventing the spread of Cistus is a priority.

Effects of climate change on seed germination may contribute to habitat homogenization in freshwater forested wetlands

Climate changes in temperate regions are expected to result in warmer, shorter winters in temperate latitudes. These changes may have consequences for germination of plant species that require a period of physiological dormancy. The effect of cold duration on seed germination has been investigated in a number of plant taxa, but has not been well studied in wetland and bottomland forest tree species, an ecosystem that is threatened by habitat homogenization. Our work sought to test the role of changing winter temperatures on seed germination in specialist (Nyssa aquatica and Taxodium distichum) and generalist (Acer rubrum and Liquidambar styraciflua) tree species within forested wetlands throughout the eastern U.S. The experiment was conducted in an environmental chamber in Norfolk, VA, USA. Seeds of T. distichum, N. aquatica, A. rubrum, and L. styraciflua were exposed to each of seven pre-germination cold exposure durations (0, 15, 30, 45, 60, 75, and 90 days) and observed for germination for 30 days. Cold stratification duration positively impacted total percent germination in N. aquatica (p < 0.0001) as well as A. rubrum (p = 0.0008) and T. distichum (p = 0.05). Liquidambar styraciflua seeds exhibited more rapid rates of germination with increasing cold exposure duration and greater percent germination compared to the others regardless of cold stratification duration. Our results provide insight into how community dynamics and biodiversity of wetland and bottomland trees may shift with a changing climate. Further, this work emphasizes the importance of understanding the role of plant functional traits in early life stages in community dynamics and has implications for management practices.

Fertilisation increases plant biomass and seed production but does not influence seed heteromorphism in Aegilops

Aegilops species are important crop wild relatives (CWR) characterised by seed heteromorphism. Within each spikelet seeds differ in terms of size, colour, phenology, abiotic stress tolerance among others. although the seed heteromorphism in Aegilops has a genetic component, the level of plasticity of this character has been poorly investigated. To fill this gap, we measured the effect of fertilization on seed heteromorphism in nine Aegilops species, to understand if nutrient availability can affect the reproductive ecology in this important CWR genus. We measured the number of stems per plant, number spikelets per stem, total dry plant biomass, seed weight and germination percentage in fertilized and control (non-fertilized) plants. Fertilization did not affect heteromorphism but increased the biomass and the number of flowering stems (hence spikelets and seeds) in fertilized plants. However, seeds produced by fertilized plants showed significantly lower germination than control plants, in a sort of trade-off between seed quantity and seed quality.

Effect of Gibberellic Acid and Mechanical Scarification on the Germination and Seedling Stages of Chenopodium quinoa Willd. under Salt Stress.

Quinoa (Chenopodium quinoa Willd.) is a facultative halophyte renowned for its importance in enhancing food security, and it supports forage production across diverse climatic regions. The objective of this study is to examine the impacts of multiple pre-treatment methods on C. quinoa seed (Titicaca cultivar) germination parameters, identify the optimum pre-treatment to diminish the consequence of salinity, and promote the productivity of this crop, especially in marginal environments. For this purpose, a spectrum of sodium chloride (NaCl) concentrations spanning from 0 to 500 mM and gibberellic acid (GA3) concentrations ranging from 0 to 300 ppm were tested, and mechanical scarification (MS) was carried out. The effect of a combination of these pretreatment NaCl/GA3 and NaCl/MS on the germination parameters of C. quinoa seed was also investigated. The results showed that the total germination, vigor index, and germination index decreased progressively with an increase in salinity. Hence, salinity exhibited a notable influence on most germination parameters. Moreover, seeds scarified with 500 mM of NaCl negatively affected all measured parameters. In contrast, gibberellic acid applied at 200 ppm was effective on most of the parameters measured, particularly under 100 mM of NaCl. These findings indicate that immersing seeds in gibberellic acid could mitigate the adverse impacts of salinity.

Determination of germination characteristics and salinity and drought tolerances of Mountain Swan (Atriplex nitens Schkuhr)

In this study, it was aimed to determine the appropriate seed germination temperature, salt tolerance, salinity and drought tolerance of seedlings in Mountain swan (Atriplex nitens). For this purpose, an experiment was established in 2021 in laboratory conditions according to the factorial experiment design in random plots and in greenhouse conditions according to the random plots experiment design with three replications. Firstly, 4 constant (10, 15, 20, 25, 30°C) and 2 variable (20/15, 25/15°C) temperatures were used in the refrigerated incubator. Total germination rates and average germination times of seeds with and without pericarp were determined. Secondly, 6 different salt concentrations (0, 100, 200, 300, 400 and 500 mM NaCl) were studied considering the optimum germination temperatures (25°C and 20/15°C). At the end of the study, germination rates (%), average germination times (days) and sensitivity indices (SI) were determined. In the last two stages, seedlings were subjected to 4 different salinity (0, 100, 200, 300, 400 and 500 mM NaCl) and 5 different drought (control, low, moderate, high and severe) tests under greenhouse conditions. At this stage, plant and root length, stem thickness, leaf area index (LAI), plant and root dry weight, root/plant ratio and tolerance percentage values were measured. As a result of the laboratory study, it was determined that seeds without pericarp had a better germination percentage than seeds with pericarp. The highest total and normal germination rates were obtained from 200 mM NaCl treatment at 20/15°C. Germination rate was determined from 0, 100 and 200 mM salt treatments at 25°C. These results showed that Atriplex nitens seeds could germinate in high salt concentrations and that their seedlings had high tolerance to drought and salinity.

Germination of aspidosperma discolor a. Dc. Under Different light and Temperature Conditions

Theoretical framework: Among the genera of the Apocynaceae family found in Brazil, Aspidosperma is among the most important, because of its high medicinal and economic value. Objective: The objective of this work was to evaluate the effects of white, far-red, and red light, and the absence of light; as well as the effects of constant temperatures of 25 ºC, 30 ºC and 35 ºC, on seed germination behavior of Aspidosperma discolor A. DC. Method: The material was collected in Atlantic Forest fragments. The germination percentage, speed index, average time and average seed germination speed were evaluated. A completely randomized design was used, and the means were compared by the Tukey test at 95% probability. A 4 x 2 factorial arrangement was used for the evaluation of the light regime (four light regimes and two origins); and for the thermal influence, a 3 x 2 arrangement (three temperature levels and two origins) was employed. Each test had five repetitions with 20 seeds. Results: The results showed that the seeds of both origins presented preferential or neutral photoblastic behavior, with better germination performance at 25 °C. However, they had total germination inhibition when exposed to 35 ºC.

Methodology of the accelerated aging test in tiny tomato seeds (solanum lycopersicum var. cerasiforme)

The objective of this study was to study whether the variations in the performance of the accelerated aging test, in terms of exposure time and temperature involved in the test methodology, performed in the traditional way or in saturated salt solution, would result in an efficient combination to evaluate the physiological quality of seeds tiny tomato (Solanum lycopersicum var. cerasiforme). The seeds were submitted to the tests of total germination, germination speed index, first germination count, substrate emergence, seedling length, seedling dry matter, cold test, electrical conductivity and variations in the conduction of the accelerated aging test. The treatments (36, 38, 40 and 42 ºC) x exposure time (24, 36, 48 and 72 hours) x procedures (traditional and saline) were used, with four replications each lot. The averages were compared by the Tukey test at 5% probability. The simple correlation coefficient (r) between the accelerated aging test results and the emergence test of substrate seedlings was also determined. The traditional accelerated aging test in the combinations of 24 hours at 36 °C and the accelerated aging test with saline in the combinations of 72 hours at 36 °C showed sensitivity for the evaluation of the physiological potential of tiny tomato seeds. For both accelerated aging tests, the temperature of 36 °C was efficient for the evaluation of the physiological potential of tiny tomato seeds.

Standardization of the accelerated aging test methodology for snap bean seed to differentiate batches by physiological quality

ABSTRACT Seed quality is extremely important for the entire production chain, given that good quality seeds contribute to obtaining vigorous and productive plants. For this reason, it is necessary to evaluate the quality of batches through vigor tests to complement the results obtained from the standard germination test. Because snap bean (Phaseolus vulgaris L.) is propagated through seed, this work was undertaken to standardize the methodology of accelerated aging test for snap bean seed compared to the standard germination test to differentiate batches in terms of physiological quality. The study utilized the cvs “Top Seed” and “Feltrin,” with 48, 72 or 96 h exposure periods and temperatures ranging from 15 to 40°C. There were four replications of 50 seeds for each condition. During the germination test, the percentage of first germination count and total germination were analyzed, and the vigor was expressed as a percentage during the accelerated aging test. The accelerated aging test for snap bean seed should be conducted at a temperature of 41°C, with an exposure period of 72 h, considering that this methodology allows differentiating seed batches in terms of physiological quality, contributing to decision-making in the seed production chain. The accelerated aging test was more efficient than the standard germination test in differentiating batches of snap bean seed, proving to be a possible alternative to evaluating the physiological quality of batches of snap bean seed.

Changes in Germination Parameters, Growth and Development of Three Cultivars of Corn Seedlings under Various Aqueous Extracts of Mallow

Abstract: Allelopathy is related to the positive or negative impacts on one type of plant of a chemical produced by another type of plant, such as weeds, and different kinds of chemicals are hydroxamic acids, phenolics, and short-chain fatty acids. The potential allelopathic impacts of weeds are directly associated with the plant species used, as well as the concentration of the aqueous extract available in the environment. The present research has made an attempt to find and identify the allelopathic effects of aquatic extracts from dry seeds and shoots of mallow (Malva sylvestris L.) on germination, seedling growth, and progress of three cultivars of maize. Maize seeds (Zea mays L.) were obtained as seed material; three maize seed cultivars were KSC 704 (cultivar 1), KSC 500 (cultivar 2), and KSC 302 (cultivar 3), respectively. The aqueous ex-tracts of mallow shoots and seeds, in concentrations of 1, 3, and 5%, were made from the crum-bled and dried above-ground plant sections. The influence of plant dosage was significant on the coefficient of the rate of germination (CRG), seedling vigour index (SVI), total germination (T50), mean germination time (MGT), germination energy (GE), germination index (GI), inhibi-tion percentage (IP), fresh mass, dry mass, relative water content (RWC), and total water content (TWC). Different plant parts had a meaningful influence on SVI, GI, MGT, CRG, GE, and IP. The impacts of the cultivar on T50, IP, RWC, fresh mass, dry mass, and TWC were significant. Together with the increase in the concentration of allelopathic components, a decline in the ger-mination activity of all tested maize cultivars was found. The highest SVI was associated with control treatment, followed by 1% and 3% of plant dosages. KSC 704 obtained the maximum CRG and GE, and the minimum one was related to KSC 500. 3% of plant dosage has obtained the highest value of CRG and GE. The maximum and the minimum T50 were related to KSC 302 and KSC 704, respectively. The lowest values of GI and MGT were related to KSC 500, and the maximum values were related to KSC 704. While the maximum IP, RWC, fresh mass, dry mass, and TWC were related to KSC 704, the lowest values were achieved for KSC 500. The RWC was the highest for seedlings grown on the 5% extract. The information provided in this article can be helpful in the conditions of the threat of maize seedlings with the mass appearance of mallow.

Ocena pokazatelja kvaliteta semena hibrida paprike tokom klijanja

The aim of the research was to evaluate the influence of the hybrid and the medium for germination testing on indicators of pepper seed quality. The obtained results should provide an answer as to whether the application of different growing media for testing seed germination can lead to discrepancies between test results in quality indicators for hybrid seeds. The seed quality of three pepper hybrids: KG 2025 F1, KG 2129 F1 and KG 2032 F1 was tested on two growing media (filter paper and substrate). Statistical analysis of germination energy, total germination, diseased seedlings and dead seeds showed highly significant differences (r&lt;0.01) under the influence of the hybrid factor. The growing media factor also had a highly significant effect on all examined quality indicators , except for total germination. A significantly lower number of abnormal and diseased seedlings was found on the filter paper compared to the substrate. A highly negative significant correlation (r =-0.90951, p≤0.001) was recorded only between total germination and diseased seedlings. The obtained results indicate that the application of different media for testing the germination of hybrid pepper seeds can lead to inconsistencies in the obtained values for all evaluated quality indicators.

Direct seeding success of four threatened oak species in a peri-urban forest: effects of microhabitat and rodent exclusion

Cloud forest degradation leads to the loss of foundational species, including oak trees, with negative and cascading effects on biodiversity. The relatively simple and inexpensive technique of direct seeding could help recover focal species in degraded peri-urban forests, but the success of this technique may be limited by mammalian seed predation. In this study, we evaluated the success of direct seeding of four sympatric and threatened oak species (Quercus germana, Q. lancifolia, Q. xalapensis, and Q. sartorii) in the cloud forest of central Veracruz. We considered the effects of planting microhabitat (low vs. high vegetation cover) and predator/disperser exclusion (total exclusion, partial exclusion, and open access to all predators) on the probability of acorn removal and germination, and on seedling emergence. Total germination was highest in Q. germana, followed by Q. lancifolia, Q. xalapensis, and Q. sartorii (52%, 32%, 29.33%, and 8.67%, respectively). Total emergence was highest in Q. lancifolia, followed by Q. xalapensis, Q. germana, and Q. sartorii (17.33%, 14.67%, 10.7%, and 2%, respectively). When acorns were exposed and unprotected in the microhabitat with high vegetation cover, removal and predation were higher (74%) than in the microhabitat with low vegetation cover (52%). Intermediate-sized acorns of Quercus xalapensis were the most frequently removed (43.33%), followed by Q. lancifolia (40%), Q. sartorii (28%), and Q. germana (26%). Seed removal was null with total exclusion of mammals, and this treatment presented the highest values of germination and emergence (54% and 22.5%, respectively), followed by partial exclusion (25.5% and 7.5%, respectively) and open access to all predators (12% and 3.5%, respectively). Microhabitat had no effect on germination and emergence. The direct seeding technique is useful for enriching degraded forests; however, its cost-efficiency depends on species attributes and predator/disperser preference. When using unprotected seeds, planting in microhabitats with low vegetation cover (<50% of vegetation cover above 30 cm) will reduce the removal and predation of acorns by 13%. To increase the success of direct seeding of oaks in degraded or secondary forests, protection of the seeds is recommended, particularly for the intermediate-sized acorns of Q. lancifolia and Q. xalapensis.

Assessment of seed viability of Oryza sativa L. accessions in long-term storage after more than a decade

The purpose of this research was to evaluate the seed viability of 16 Oryza sativa L. accessions including valuable endangered landraces, a breeder’s line, and an advanced/improved cultivar after 13-14 years of long-term storage. Preservation of seed samples has been conducted ex-situ at low temperatures (-18°C). The germination test (germination energy and total germination) was carried out according to ISTA methods and Kameswara (2006). Furthermore, the following variables were examined: the germination index, root length, shoot length, root-to-shoot length ratio, total seedling length, and seed vigour index. The Pearson correlation coefficient was computed to assess the linear relationship between the vigour index and seedling length. All the sixteen accessions have had a high total germination rate, in the range of 89-100%, hence there is no need for their regeneration. The germination energy and total germination showed statistically significant differences for two rice accessions at P-0.05 and P-0.01. The seed showing a high vigour index produced seedlings with higher growth rates. The Pearson correlation of the vigour index and seedling length was found to be very highly positive and statistically significant (r=0.99, p0.001). Based on the results obtained, it can be concluded that rice as a botanical species retains high seed viability during the long-term conservation, although there are individual differences between the accessions which are due to the genetic constitution of each genotype.

Preparation and Characterization of New and Low-Cost Ceramic Flat Membranes Based on Zeolite-Clay for the Removal of Indigo Blue Dye Molecules.

Composite flat membranes were prepared using a dry uniaxial pressing process. The effect of the sintering temperature (850-950 °C) and smectite proportion (10-50 wt.%) on membrane properties, such as microstructure, mechanical strength, water permeability, and treatment performances, was explored. It was observed that increasing the sintering temperature and adding higher amounts of smectite increased the mechanical strength and shrinkage. Therefore, 850 °C was chosen as the optimum sintering temperature because the composite membranes had a very low shrinkage that did not exceed 5% with high mechanical strength, above 23 MPa. The study of smectite addition (10-50 wt.%) showed that the pore size and water permeability were significantly reduced from 0.98 to 0.75 µm and from 623 to 371 L·h-1·m-2·bar-1, respectively. Furthermore, the application of the used membranes in the treatment of indigo blue (IB) solutions exhibited an almost total turbidity removal. While the removal of color and COD decreased from 95% to 76%, respectively, they decreased from 95% to 52% when the amount of smectite increased. To verify the treated water's low toxicity, a germination test was performed. It has been shown that the total germination of linseed grains irrigated by MS10-Z90 membrane permeate was identical to that irrigated with distilled water. Finally, based on its promising properties, its excellent separation efficiency, and its low energy consumption, the MS10-Z90 (10 wt.% smectite and 90 wt.% zeolite) sintered at 850 °C could be recommended for the treatment of colored industrial wastewater.

Seed pelleting and storage effects on germination of Pennycress (Thlaspi arvense L.)

AbstractPennycress (Thlaspi arvense L.) is an emerging bioenergy oilseed crop of interest to farmers in the Upper Midwestern United States. Improved lines with beneficial agronomic traits are being developed, including lines with reduced silicle shattering and altered seed coat characteristics, though planting and establishment is still challenging for this small‐seeded crop. A controlled‐environment experiment was conducted to assess the impact of seed treatment and pelleting on pennycress germination and seedling vigor of four pennycress lines (three black and one golden colored seed) following storage for 0, 1, 3, 9, and 12 months in warm or cold conditions (23°C or 10°C, respectively). Seeds were either treated with a gibberellin A4+7 (GA) soak (positive control), seed pelleting, or pelleting with GA added to the binder solution in addition to the untreated control (negative control). After each storage duration, seeds were germinated in darkness and counted daily for 7 days to obtain total germination. Vigor indices were calculated using changes in daily germination values. For black‐seeded lines, GA treatment increased germination over the untreated by 5%–75% and pelleting alone increased germination by 4%–30%, but only until 3 months of storage. The GA treatment did not increase germination of the golden‐seeded line, and pelleting decreased germination after 3 months of storage. The GA soak treatment was most effective at improving seed vigor indices compared with other treatments, while pelleting negatively affected vigor scores at 9 and 12 months of storage. Similar effects on germination from treatment were observed under both warm and cold storage conditions. Results indicate seed treatment can benefit germination and vigor within 3 months of storage for black‐seeded lines but may negatively affect performance of golden‐seeded lines, or all pennycress seed types after 9 months of storage.

The Oxidation and Functionalization of Multi-walled Carbon Nanotubes with Fluorescein-isothiocyanate Improve Germination and Early Development of Avena sativa.

The use of multiwalled carbon nanotubes (MWCNTs) in plant systems has been extensively studied in the last decade, however, the structural modification of these nanoparticles changes the effects when interacting with biological systems, so this work gives us more information on the effects of the oxidation and functionalization of the MWCNTs, where these nanoparticles increased the speed of germination as well as the total germination and in the same way improved the biomass of the plant.

Ensiling, In Vitro Rumen Digestion and Soaking in Slurry Altered the Germination Capacity of Rumex obtusifolius Seeds

This study investigated whether the process of ensiling and in vitro digestion in rumen juice, as well as the response to soaking in pig or cattle slurry, affects the germination rate and germination energy of Rumex obtusifolius (broad-leaved dock) seeds. Seeds were subjected to different treatments (200 seeds each) in three experiments: (I) seed ensiling (8 weeks) followed by in vitro rumen digestion (24, 36 and 48 h); (II) the soaking of non-ensiled and ensiled seeds in cattle or pig slurry (2, 4 and 24 weeks); and (III) the in vitro rumen digestion (24, 36 and 48 h) of non-ensiled and ensiled seeds followed by soaking in cattle or pig slurry (24 weeks). The control treatment included untreated seed (0—non-ensiled seed; 0—no in vitro rumen digestion; and 0—no soaking in slurry). Germination tests (germination rate and germination energy) were then conducted in four replicates in the germination chamber under alternating day (20–35 °C for 14 h under light) and night conditions (17–20 °C for 10 h without light) at 75% relative humidity. Experiment I showed that ensiling significantly (p ≤ 0.001) reduced both the germination rate and germination energy of R. obtusifolius seeds. In addition, the length of in vitro digestion duration that the non-ensiled seeds were subjected to significantly (p ≤ 0.001) reduced their germination energy but not the total germination rate. However, the seeds that were subjected to the process of ensiling and in vitro digestion in the rumen lost their germination completely. The Experiment II investigated the effects of soaking non-ensiled seeds in slurry and showed that germination rates were comparable in pig and cattle slurry. Longer soaking times significantly reduced the germination rate, with no germination observed after 24 weeks. The Experiment III considered the combined effects of in vitro digestion and slurry soaking and showed that rumen digestion reduced the proportion of germinable seeds. Germination was inhibited in pig slurry, while in cattle slurry, a decreasing germination rate was observed with increasing digestion time.

Seed biopriming at different concentrations to assess the effects of Cyanobacteria on germination and seedling performance of keystone arid species

AbstractIntroductionBiocrust cyanobacteria have a large potential as biofertilizers for restoring degraded ecosystems because of their ability to improve soil nutrition and stabilisation, and to produce metabolites such as phytohormones to enhance plant growth. However, important aspects regarding the effects of cyanobacteria on native plants, such as metabolite production or concentration of inoculants, remain unknown. Here, we investigated the effects of different concentrations of cyanobacteria, on the germination and seedling growth of keystone plant species used in dryland restoration. We hypothesised that the studied inoculant would improve germination and seedling growth rates, with specific effects associated with the inoculant's concentration and metabolomic profiles.MethodsWe bioprimed seeds of four native plant species, using a cyanobacterial inoculant with different proportions of Nostoc and Leptolyngbya at two different concentrations. We recorded germination, measured seedling growth, and determined the corrected vigour for each treatment and species. Metabolites produced by the cyanobacterial inoculant were assessed to identify plant growth hormones potentially driving any effects.ResultsThere was a clear positive effect on the total germination of Triodia epactia and Triodia wiseana, but negative impacts for Senna notabilis and Grevillea wickhamii. There were also positive effects on root growth, but only for T. epactia, with negative or neutral impacts on the root and shoot growth of other species tested. We detected phytohormones, salicylic acid and indole‐3‐acetic acid, that were produced by our cyanobacteria inoculant, which are strongly linked to positive effects in early plant growth stages, but also known to inhibit growth when in higher concentrations.ConclusionThe positive effects of the biopriming protocol used are not uniform and highlight the need to improve our understanding of the effects provided both from different consortia and the concentrations applied when inoculating. There is a very high value in improving restoration outcomes for native vegetation communities in arid and semi‐arid regions.

О значении хемосистематической корреляции при изучении аллелопатического потенциала аборигенных и чужеродных видов трав

This abstract presents the results of screening for allelopathic activity of three pairs “aboriginal-exotic” of comparison species of herbs, including invasive species, systematically related at the level of the genus. It was shown that a 1% leaf extract of Solidago virgaurea and S. canadensis, Pulmonaria obscura and P. saccharata, Veronica serpyllifolia and V. filiformis had a similar or equal inhibitory effect on the germination and growth of test-plant roots in biotests owing to its chemosystematic correlation. Extracts of Solidago and Pulmonaria species slowed down the rate of germination and root growth by 1.5–2 times lower than the control. In the Salidago sp. experiment options the dynamics of the processes developed according to the type of stress-reaction. The absolute rate of root growth at the exponential stage differed twice in the Solidago sp. options: 16.8±0.43 and 8.99±0.23 mm/day in native and exotic specie, respectively. The total germination was close to or equal to the control level. In a comparison pair Pulmonaria sp. germination decreased by 58.66 and 43.5%. V. filiformis extract inhibited germination by 24.4% more than the native species. Extracts 0.05% extracts of Solidago sp. had no effect, P. saccharata and V. filiformis extracts caused the effects of hormesis. P. saccharate option produced an – acceleration of the absolute and relative root growth rate of the test-plants by two times, exceeding the total length of the roots by half compared to the control and the native species. In the V. filiformis option, the rates of germination and root growth was inhibited by 24.7 and 50.2% of the values of the paired species, respectively. The comparative method increases the level of analysis of bioassay data, allows for a deeper study of the specifics of test-plants reactions, and allows the evaluation of the modes of action of allelochemics.