Germination Process Research Articles

The pivotal role of water potential in phenology and seed germination of Abies spectabilis in the western Himalayan treeline region

Abies spectabilis (East Himalayan Fir), a dominant timber-producing species in the Himalayas, plays a dynamic role in ecological balance and sustains various habitats across temperate to subalpine altitudes. Himalayan montane forests express signs of changes in the growth, regeneration, and population density of forest tree species due to ongoing climate change, including its upper distribution limit. The research was conducted at 30°11´02˝N and 79°39′36˝E, ranging from 3,100 to 3,500 m asl elevation in the treeline ecotone of western Himalaya. The study presents a comprehensive perspective on how water availability and its intricate interactions with climatic and ecological variables shape the dynamics of treeline ecosystems. The study’s phytosociological analysis of treeline sites revealed the complex interplay between species composition, adaptability, and regeneration potential. The eco-physiological aspects of water balance were thoroughly explored, underscoring how plants employ various strategies to cope with changing water availability. The soil moisture content ranged from 32.17 to 73.50%. The dynamic nature of water potential (pre-dawn (ΨPD) and mid-day (ΨMD)) across seasons and years reflects and varies between −0.13 and − 1.25 MPa, the species’ ability to adjust and manage water balance according to environmental shifts. Osmotic potential at full turgor varied from −0.72 to −1.77 MPa, these adjustments are crucial for key life cycle events of vegetative and reproductive phases of species. The strong correlation of water potential (Ψ) and phenophases emphasizes the importance of water status in regulating these vital processes. Furthermore, the study delved into the maturation and germination processes, highlighting the significance of Ψ and moisture content in seed development and germination success. The maximum germination of 46.33% was observed when the seed moisture content was 30.90 ± 3.11%. The observed correlations between cone characteristics and seed parameters indicate the existence of trade-offs that impact seed size, weight, and germination capacity, contributing to the overall fitness of the species.

The exposure of lead nitrate on germination and vigor processes of Helianthus (sunflower) and Lathyrus (pea) seeds

It is hereby studied the exposure of lead ions on germination and growth viability of helianthus and lathyrus seeds in laboratory conditions. Certain tendencies have been revealed showing the impact of different doses of the lead ions on germination of helianthus and lathyrus as well as on the length of the root and sprout in germinating the seed. Furthermore, a particular decrease (P<0.99) in the helianthus seed germination was observed under the lead exposure at the concentration of 5×10–3 mol/L. Whereas, at the lead ions concentration in their amount from 5×10–6 mol/L to 5×10–4 mol/L, no considerable influence on helianthus and lathyrus seed germination was noticed. However, the helianthus and lathyrus root length has been exposed by the lead ions more significantly. It was noticed that the helianthus root had significantly decreased in length at the lead ions concentration of 5×10–3 mol/L, 5×10–4 mol/L, 5×10–5 mol/L and 5×10–6 mol/L (P<0.999, P<0.999, P<0.99 and P<0.999, respectively). The difference in terms of the lathyrus root length at 5×10–3 mol/L, 5×10–4 mol/L, 5×10–5 mol/L and 5×10–6 mol/L concentration of lead ions was found significant (P<0.955, P<0.99, P<0.95 and P<0.99, respectively). The study results with regard to the exposure of different doses of the lead nitrate on the average length of the helianthus sprout showed an significant difference rate (P<0.999) in these values at the lead ions concentration in the solution of 5×10–3 mol/L, 5×10–5 mol/L and 5×10–6 mol/L. There was no significant difference between the lathyrus sprout length under the lead ions exposure between 5×10–6 mol/L and 5×10–3 mol/L. Thus, as far as the research results are concerned, there has been highlighted a significant lead nitrate exposure on economically useful indicators of the helianthus and lathyrus growing. A clear tendency of the lead nitrate impact on the helianthus and lathyrus seed germination and on their root and sprout length was revealed.

Physical seed damage, not rodent's saliva, accelerates seed germination of trees in a subtropical forest.

Many tree species adopt fast seed germination to escape the predation risk by rodents. Physical seed damage and the saliva of rodents on partially consumed seeds may act as cues for seeds to accelerate germination process. However, the impacts of these factors on seed germination rate and speed remain unclear. In this study, we investigated such impacts on the germination rate and speed (reversal of germination time) of four tree species (Quercus variabilis, Q. serrata, Q. acutissima, Q. glauca) after partial consumption by four rodent species (Leopoldamys edwards, Niviventer fulvescens, N. confucianus, Apodemus draco), through a series of experiments. We also examined how seed traits may affect the seed damage degree by rodents by analyzing the relationship between the germination rate and time of rodent-damaged seed and the traits. We found that, artificially- and rodent-damaged seeds exhibited a significantly higher seed germination rate and speed, compared to intact seeds. Also, the rodent saliva on seeds showed no significant effect on seed germination rate and speed. Furthermore, we observed significant positive correlations between several seed traits (including the seed mass, coat thickness, and protein content) and the seed germination rate and speed. These correlations are likely due to their beneficial traits countering seed damage by rodents. Overall, our results highlight the significant role of physical seed damage by rodents (rather than their saliva) in facilitating seed germination of tree species, and potential mutualism between rodents and trees. Additionally, our results may have some implications in forest restoration, such that intentionally sowing or dispersing slightly damaged seeds by humans or drones may increase the likelihood of successful seed regeneration.

Influencia del parental masculino sobre el poder germinativo de semillas de palma aceitera

The National Institute of Agricultural Research (INIAP) uses female parentals (Dura -Deli) and male parentals (Pisifera) from different origins to obtain the hybrid INIAP -Tenera of oil palm (Elaeis guineensis Jacq). The objective was to evaluate the influence of the male parental on the germination of African oil palm seeds. Seeds from 20 bunches, resulting from the crossing of 10 Dura plants with pollen from two Pisifera plants, were subjected to the germination process. The process involved eight days of imbibition 1, 80 days of heating, 24 hours of drying, four days of imbibition 2, and six hours of drying. One hundred seeds per treatment and per repetition were evaluated using a completely randomized design, assisted by Tukey's test at 5%. The results showed that seeds from Dura plants D1, D8, and D9 crossed with the male parental P1 achieved a higher percentage of optimal germination and statistical differences compared to seeds from the same Dura plants crossed with Pisifera P2. Of the 10 Duraprogenitors studied, seven (D1, D3, D4, D5, D8, D9, D10) crossed with Pisifera P1 achieved an average optimal germination rate above 50%, while only two of the Dura plants (D3 and D5) evaluated and crossed with Pisifera P2 achieved an optimal germination rate equal to or above 50%. This demonstrated that the germination of Tenera seeds (Dura x Pisifera) of African oil palm is highly related to the male parental use.

In vitro production of Phalaenopsis orchids

Phalaenopsis – known as moth orchids – are the most popular orchids cultivated indoors as decorative house plants. This makes propagation and cultivation of Phalaenopsis important for commercial growers. Enhancements to the micropropagation of Phalaenopsis would have pronounced economic benefits through reduced losses and wastage. We examined the effects of several nutrient media and specific plant growth regulators (PGRs) belonging to the gibberellic acid and cytokinin groups on the in vitro germination of Phalaenopsis seeds, utilizing a single-group pretest-posttest model. The effects of several nutrient media such as: Knudson C (KCM), Lindemann (LM), Orchimax (-OM), Orchimax + activated charcoal (+OM), Murashige & Skoog (MS), as well as various PGRs such as 6-Benzylaminopurine (6BA), 6-Furfurylaminopurine (KIN), Adenin hemisulfate (AHS), Thidiazuron (TDZ), 2-Isopentenyl adenine (2iP), and Gibberellic acid (GA3), on the process of germination were also investigated. The explants obtained from the germinating seedlings were subjected to direct organogenesis, and the optimal PGR and tissue fragments were determined. The +OM medium facilitated the shortest germination period (in days). An inverse relationship between the concentration of TDZ and the percentage of germination in the context of the employed PGRs was observed. Apart from TDZ, the remaining PGRs exhibited a positive correlation with concentration. However, no significant difference in germination was observed in comparison to the control. The findings of direct organogenesis investigations revealed that the medium that exhibited the highest productivity was enriched with 5.0 ppm of 6BA. The media containing TDZ exhibited a reduced level of efficiency. Particularly, the group treated with 1.0 ppm of TDZ exhibited reduced efficacy compared to the control group. All concentrations of cytokinin in root elongation stage exhibited a favorable impact in comparison to the control. The variance between these PGRs was not statistically significant.

Некоторые особенности биологии редкого эндемичного вида Arafoe aromatica Pimenov & Lavrova на территории Рицинского реликтового национального парка (Республика Абхазия)

For the first time, the features of rare endemic species of Caucasus Arafoe aromatica biology in the Ritsa Strict Nature Reserve (Republic of Abkhazia) were studied. The age, vitality structure of coenopopulations (CP) and the variability of morphometric parameters were determined. The study was carried out using standard methods of population biology. The variability of morphometric parameters was studied on 25 middle-aged plants in each CP. The CP density is low (1–2.6 ind./m2). According to the delta-omega classification, one CP is transitional, and one is mature. Most of the morphological features are characterized by a normal degree of variation (14.7–37.0%). Vitality analysis showed that one CP is prosperous, the other is depressed. The state of the studied A. aromatica coenopopulations is satisfactory. Anthropogenic disturbances lead to a decrease in the number and seed productivity, worsening conditions for seed germination and renewal processes. To preserve the rare species, it is necessary to limit the anthropogenic load in the places of growth, prohibit the collection of plants by the population, monitor and control the CP state.

Incorporation of germinated lupin into corn-based extrudates: Focus on starch digestibility, matrix structure and physicochemical properties

The research aimed to assess the effects of incorporating germinated Lupinus angustifolius flour into corn extrudates for different periods (3, 5, and 7 days), focusing on starch digestibility, morphological structure, thermal, and pasting properties. Extrudate with germinated lupinus flour for 7 days (EG7) significantly increased the content of slowly digestible starch up to 10.56% (p < 0.05). Crystallinity increased up to 20% in extrudates with germinated flour compared to extrudates with ungerminated flour (EUG), observing changes at the molecular level by FTIR that impact the thermal and pasting properties. X-ray diffraction revealed angles of 2θ = 11.31, 16.60, 19.91, and 33.04 as a result of the germination and extrusion processes. Microstructural analysis indicated starch-protein interactions influencing changes in calorimetry, viscosity, X-ray diffraction, and digestibility. PCA allowed establishing that the addition of germinated flours significantly affected the properties and microstructural characteristics of extruded products, potentially affecting digestibility and nutritional quality.

Зміни жирнокислотного складу проростків кукурудзи за впливу мікробіологічного комплексу

Orientation of agricultural production to ecological expediency leads to interest in the use of microbial preparations that are able to increase the resistance of plants to negative environmental factors and activate germination processes. This study was conducted with the aim to investigate the influence of a microbiological complex on the sowing properties of seeds and the fatty acid composition of seedlings of different breeding samples of corn. Methods. Corn seeds of two lines 1-Ak026 and 2-Ak033 and their simple interline hybrid, which is the parent component of the three-line hybrid NUBiSe included in the State Register of plant varieties suitable for distribution in Ukraine, were used for the research. Seed inoculation was carried out with a microbial complex, which contained biological preparations Sporazyn, Avercom, and Phytovit. Seedlings from the seeds of the corresponding corn samples not treated with the microbial complex served as controls. The fatty acid composition of lipids was determined in the biological material of corn seedlings of different variants of the experiment. The Folch method was used to extract fats from plant material. Hydrolysis and methylation of fatty acids of lipids obtained from corn seedlings was carried out according to DSTU ISO 5509-2002. Fatty acids were detected and identified by gas chromatography. The quantity of fatty acids was calculated by the method of internal normalization in percentages. Results. The influence of the microbiological complex on the quantitative and qualitative composition of fatty acids of the lipid complex of corn seedlings was established, which depended on the breeding sample. In the process of research, 22 fatty acids were detected and quantitatively identified in corn seedlings. In the seedlings of lines 1-Ak033 and 2-Ak033, 20 and 19 of them were found, respectively, and in the hybrid – 18. The highest percentage content (more than 90 %) was revealed for palmitic (C16:0), oleic (C18:1n9c), and linoleic (C18:2ω6c) fatty acids. The use of the microbial complex made it possible to detect the fatty acids in line 1 and the hybrid that were not detected in the samples without inoculation. Conclusions. The study of the fatty acid composition of the microbial preparation Sporazyn revealed the highest content of unsaturated fatty acids (67.47 %) and the ratio of saturated to unsaturated (0.48). The use of microbiological preparations on corn seeds increased the activity of the germination processes, which led to the improvement of sowing properties and changes in the fatty acid composition of the lipid complex of seedlings of various breeding forms of Zea mays.

The Impact of ZnO and Fe2O3 Nanoparticles on Sunflower Seed Germination, Phenolic Content and Antiglycation Potential.

The enhancement of seed germination by using nanoparticles (NPs) holds the potential to elicit the synthesis of more desired compounds with important biomedical applications, such as preventing protein glycation, which occurs in diabetes. Here, we used 7 nm and 100 nm ZnO and 4.5 nm and 16.7 nm Fe2O3 NPs to treat sunflower seeds. We evaluated the effects on germination, total phenolic content, and the anti-glycation potential of extracted polyphenols. Sunflower seeds were allowed to germinate in vitro after soaking in NP solutions of different concentrations. Polyphenols were extracted, dosed, and used in serum albumin glycation experiments. The germination speed of seeds was significantly increased by the 100 nm ZnO NPs and significantly decreased by the 4.5 nm Fe2O3 NPs. The total phenolic content (TPC) of seeds was influenced by the type of NP, as ZnO NPs enhanced TPC, and the size of the NPs, as smaller NPs led to improved parameters. The polyphenols extracted from seeds inhibited protein glycation, especially those extracted from seeds treated with 7 nm ZnO. The usage of NPs impacted the germination speed and total polyphenol content of sunflower seeds, highlighting the importance of NP type and size in the germination process.

ANTIOXIDANT ENZYMES INVOLVED IN SEEDS’ GERMINATION MODULATED BY ACTIVE PRINCIPLES FROM PLANT EXTRACTS AND HYDROLYZED PROTEINS

Transition to organic farming requires the development of new methods to protect seeds from adverse factors. The germinative process and the post-germinative phase are strictly controlled by the oxidative balance involving lipid peroxidation, reactive oxygen species and enzymes activity, directing the plant viability and its further development. We focus our studies mainly on the seeds protection and fortification through natural solutions based on marigold and fenugreek extracts, steroid alkaloids from tomatoes and hydrolyzed proteins derived from leather waste industry. The structural configuration of the plant protection products proves significant effects fighting on different mechanisms of seeds’ oxidative stress. As well as the experimental design highlighted a tandem correlative mechanism between germination, decrease of lipid peroxidase and activation of catalase and superoxide-dismutase. SEM-PROTECT II was the most active biopesticide involved in these processes. Our findings directed complex research oriented to technological and experimental optimizations for the development of an innovative, efficient and competitive plant protection product to meet modern agriculture requirement.

Facilitating Seed Iron Uptake through Amine-Epoxide Microgels: A Novel Approach to Enhance Cucumber (Cucumis sativus) Germination.

Enhancing the initial stages of plant growth by using polymeric gels for seed priming presents a significant challenge. This study aimed to investigate a microgel derived from polyetheramine-poly(propylene oxide) (PPO) and a bisepoxide (referred to as micro-PPO) as a promising alternative to optimize the seed germination process. The micro-PPO integrated with an iron micronutrient showed a positive impact on seed germination compared with control (Fe solutions) in which the root length yield improved up to 39%. Therefore, the element map by synchrotron-based X-ray fluorescence shows that the Fe intensities in the seed primers with the micro-PPO-Fe gel are about 3-fold higher than those in the control group, leading to a gradual distribution of Fe species through most internal embryo tissues. The use of micro-PPO for seed priming underscores their potential for industrial applications due to the nontoxicity results in zebrafish assays and environmentally friendly synthesis of the water-dispersible monomers employed.

Assessing Falling Number Stability Increases the Genomic Prediction Ability of Pre-Harvest Sprouting Resistance in Common Winter Wheat.

Pre-harvest sprouting (PHS) resistance is a complex trait, and many genes influencing the germination process of winter wheat have already been described. In the light of interannual climate variation, breeding for PHS resistance will remain mandatory for wheat breeders. Several tests and traits are used to assess PHS resistance, i.e., sprouting scores, germination index, and falling number (FN), but the variation of these traits is highly dependent on the weather conditions during field trials. Here, we present a method to assess falling number stability (FNS) employing an after-ripening period and the wetting of the kernels to improve trait variation and thus trait heritability. Different genome-based prediction scenarios within and across two subsequent seasons based on overall 400 breeding lines were applied to assess the predictive abilities of the different traits. Based on FNS, the genome-based prediction of the breeding values of wheat breeding material showed higher correlations across seasons (r=0.505-0.548) compared to those obtained for other traits for PHS assessment (r=0.216-0.501). By weighting PHS-associated quantitative trait loci (QTL) in the prediction model, the average predictive abilities for FNS increased from 0.585 to 0.648 within the season 2014/2015 and from 0.649 to 0.714 within the season 2015/2016. We found that markers in the Phs-A1 region on chromosome 4A had the highest effect on the predictive abilities for FNS, confirming the influence of this QTL in wheat breeding material, whereas the dwarfing genes Rht-B1 and Rht-D1 and the wheat-rye translocated chromosome T1RS.1BL exhibited effects, which are well-known, on FN per se exclusively.

Effect of high static electric field on germination and early stage of growth of Avena sativa and Raphanus sativus

Presented study investigated the impact of a stationary electric field with an average value of 185 kV/m on the germination process and early growth of radish (Raphanus sativus – a eudicot plant) and oat (Avena sativa – a monocot plant). Electric field stimulation may prove to be one method to sustainably increase crop efficiency. The research is aimed to increase knowledge of the effect of a static electric field on the plant growth process, because understanding of the topic is still limited. The plants were grown on a viscose substrate in a dark room without any light. Studies have shown that the electric field can affect the germination and growth process depending on the plant species. The findings indicate a positive influence of the electric field on radish germination. The presence of the electric field accelerates the germination process and growth of young plants. On the first day of germination (the 3rd day of cultivation), about 3.2 times as many plants germinated in the samples exposed to a stationary electric field compared to the control samples. On the last day of the experiment (the 8th day of cultivation), the tallest plants in the samples subjected to the electric field were 8 % higher, compared to the tallest plants in the control samples. On the other hand, the results demonstrate a negative impact of the electric field on oat seed germination. The presence of an electric field delays the germination process and reduces the number of germinated seeds. On the last day of the experiment (the 11th day of cultivation), about 1.25 times fewer oat plants germinated in the samples exposed to a stationary electric field compared to the control samples. The tallest plants in the samples subjected to the electric field were 1.1 times smaller than the tallest plants in the control samples.

Effective dye detoxification by Cassia fistula flower extract- powered photocatalytic nanocomposite, SnO2:Mo/rGO and phytotoxicity evaluation of treated water using cowpea seeds

As industrial effluents consisting of toxic organic dye molecules cause severe harms to humans and damages to the environment, the detoxification of industrial waste water becomes one of the priority areas to be considered by countries all over the world. In this context, the present study is focused on the synthesis of an eco-friendly nanocomposite SnO2:Mo/rGO to photo-catalytically detoxify dye effluents. The detoxifying efficiency of this photocatalytic nanocomposite prepared using the flower extract of Cassia fistula was examined by decomposing methylene blue (cationic-MB) and rose bengal (anionic-RB) dyes. The nanocomposite is found to be superior compared to its constituents (SnO2:Mo and rGO) for both MB (99 %) and RB (98 %) dyes. After treatment, the water was examined for its non-toxicity by supplying it for seed germination process using Cowpea seeds (Vigna unguiculata). The seed germination results clearly reveal that near complete detoxification of dye solution is achieved, when SnO2:Mo/rGO nanocomposite is used as photocatalyst. Thus, the SnO2:Mo/rGO nanocomposite synthesized using Cassia fistula flower extract can be considered as a potential photocatalyst for commercial dye detoxification processes.

Germinated VD20 rice – a local rice variety in Vietnam: Effect of process conditions

Rice is one of important staple foods, which mainly consumed by human in daily life. One of the methods which could enhance the nutritional profile as well as functional of rice is germination process. VD20 rice, a local rice from Tien Giang province (Vietnam), was used in this study. This investigation was aimed to study the effect of ratio of rice to soaking solution (1:1-1:3), pH of soaking solution (distilled water, pH = 3-5), and time of soaking (3-6 hours) on the germination rate, moisture content of grain and total polyphenol content of germinated rice. Besides that, the impact of germination conditions, including incubation time (16-22 hours) and temperature (31-37oC), on the quality of germinated rice was also elucidated. The obtained results showed the ratio of soaking water to rice is 2.5:1 for the highest polyphenol content and germination rate. The longer the soaking time, the polyphenol content gradually decreases but the germination rate gradually increases over time. Soaking solutions with a pH of 4 for 6 hours were the most apporiate conditions for soaking VD20 rice. During the germination process, temperature and incubation time significant affected the polyphenol content and germination rate. At a temperature of 37℃ for 20 hours, the polyphenol content was highest (33.85 mgGAE/100 g) and gradually decreases with incubation time, but the germination rate gradually increases. Germination process of VD20 enhance the nutrional quality of rice, which could be seen in the increasing of phenolic compounds content. However, it also affected by various factors, as know as, soaking conditions and incubation conditions, which could further study to ultilize and optimize. The obtained product also have the promising application as the nutraceutical food.

Ultrasound-assisted germination of red kidney beans: Enhancements in physicochemical and nutritional profiles

To improve the conventional germination process and improve the nutritional quality of red kidney beans, this study employed high-intensity ultrasound (HIU) supplemented with hydrogen peroxide as a pre-germination treatment. The results showed that the 350 W-10 min treatment yielded the highest germination rate (77.09%), with its sprout length 81.13% greater than that of the control group. The 350 W-10 min treatment increased total protein, soluble protein, and ash content, while simultaneously reducing the fat, starch, and soluble sugar content. The HIU treatment accelerated the accumulation of phenolic and flavonoid compounds, ascorbic acid, and γ-aminobutyric acid. The 350 W-10 min treatment also decreased the levels of phytic acid, trypsin inhibitor activity, and tannin by 42.71%, 65.58%, and 53.18%, respectively. Furthermore, ultrasonic cavitation enhanced antioxidative capacity and improved amino acid composition and protein digestibility. Consequently, HIU serves as a cost-efficient method to accelerate the germination process and enhance their nutritional composition.

Effect of heating and germination on bioactive properties, phenolic compounds, fatty acid and mineral contents of quinoa (Chenopodium quinoa Willd.) seeds

SummaryIn this study, the effect of roasting, boiling and germination processes on bioactive compounds, antioxidant activity, fatty acid and phenolic profiles and biogenic elements of quinoa seed and oils was assigned. The moisture amounts of boiled and germinated quinoa seeds were recorded to be significantly higher than the control. Also, the oil yield of quinoa seeds decreased compared with the control by roasting, boiling and germinating. The total phenolic and flavonoid quantities of quinoa seeds were assigned to be between 137.70 (germinated) and 315.00 (boiled) to 156.62 (boiled) and 402.38 mg/100 g (control), respectively. Antioxidant capacities of processed quinoa seeds were reported to be between 11.91 (germinated) and 14.43 mmol kg−1 (roasted). The highest total flavonoid and antioxidant capacities were recorded in the control group and roasted quinoa seeds. The highest decrease in total phenol amount of quinoa seeds was detected in germinated quinoa. Gallic acid and catechin values of quinoa seeds varied to be between 29.17 (boiled) and 38.00 mg/100 g (control) to 2.72 (germinated) and 137.26 mg/100 g (control), respectively. The rutin, ferulic acid and p‐coumaric acid contents of the processed (roasted, boiled and germinated) quinoa seeds gradually increased compared with the control. The highest palmitic, oleic, behenic and arachidonic acids were recorded in germinated quinoa oil, followed by the fatty acids of boiled, raw (control) and roasted quinoa seed oils in descending order. P and K amounts of quinoa were established to be between 2203.44 (roasted) and 3314.59 (control) to 4350.60 (boiled) and 6266.85 mg kg−1 (control), respectively.

ВЛИЯНИЕ РАСТВОРОВ ПЕРОКСИДА ВОДОРОДА РАЗНЫХ СОСТАВОВ НА ПРОРАСТАНИЕ СЕМЯН ОГУРЦА

A method has been developed for producing pure hydrogen peroxide without admixture of NOx by replacing the nitrogen medium stabilizing the flare microwave discharge with water vapor when distilled water and its vapor at atmospheric pressure are treated with pure inert argon plasma. The dynamics of seed germination and development of cucumber seedlings in pure solutions of hydrogen peroxide, in solutions of medical 3% hydrogen peroxide stabilized with sodium benzoate, and in distilled water in the control were studied. The concentrations of hydrogen peroxide solutions in the range from 0,1 mg/l to 10 mg/l were used. Cucumber seeds «Competitor» with reduced germination (the result of long-term storage) were selected as a test object. Seeds of 30 pieces were placed in Petri dishes on filters, moistened once in the experiment with the studied solutions, and in the control with distilled water. It is shown that the germination of seeds and the development of seedlings in pure solutions of hydrogen peroxide reaches 95% at a concentration of hydrogen peroxide of 1,7 mg/l, while when using medical peroxide, the same indicator was 75% at a concentration of 0,1 mg/l. Higher concentrations of medical peroxide gave the worst result, in particular, concentrations of 3,3 mg/l and 10 mg/l led to inhibition of the seed germination process and showed the worst result.

Seed morphometry and NaCl and sucrose effect on germination rates and phytochemicals in sotol (Dasylirion acrotrichum) from the Chihuahua state, Mexico

In Mexico, “sotoles” (Dasylirion spp.) are used to elaborate the “sotol” liquor, handicraft making, and construction materials. These activities have enhanced the probability that sotol populations could decline because plants are extracted directly from their native ecosystems, given no commercial sotol plant species exist. Furthermore, from an ecological point of view, this genus has also been little studied regarding its seed morphology and germination process. The objective of this study was to characterize the morphometry of the D. acrotrichum seeds and to evaluate the effect of different concentrations of NaCl (30, 60, and 90 mM) and sucrose (30, 60, and 90 mM) on seed germination rates, seedling morphology, and the phytochemical content in the seedling leaves under in vitro conditions from plants grown in the Chihuahua State. The exogenous NaCl and sucrose treatments influenced the germination speed index, mean germination time, and mean germination speed. The NaCl treatment impacted the total weight, root weight, and leaf length of seedlings, the content of chlorophyll a, sugar, and phenolics, and the antioxidant activity determined by FRAP. Besides, the sucrose treatment affected the seedling length, the content of chlorophyll a, chlorophyll b, total chlorophyll, and sugars, and the antioxidant activity determined by FRAP and DPPH. These results could provide the guidelines to generate better afforestation programs in the areas affected by the overexploitation of the Dasylirion spp. and new information about the capacity of these species for developing under these types of stress in the natural environment.

Embryo growth and seed germination requirements in underdeveloped embryos of Elwendia caroides and E. wolfii (Apiaceae)

Elwendia wolfii and E. caroides are two herbaceous perennials that were initially classified in the Bunium genus and later transferred to the Elwendia genus. They are a rich source of bioactive and antioxidant compounds and have the potential to become sources of oil-bearing crops. The aim of this study was to investigate requirements for embryo growth, dormancy break and seed germination in these two species. The effects of gibberellic acid (GA3) and dry storage were also examined to determine the type of dormancy. The pericarps and seed coats of both species were water-permeable, and the embryos were small and differentiated but underdeveloped, with initial embryo lengths of 0.28 mm in E. wolfii and 0.96 mm in E. caroides, respectively. These underdeveloped embryos were either di (&gt;98%) or tricotyledonous (&lt;2%) and required cold temperatures to grow, indicating that these seeds had morphological dormancy (MD). The critical length required for germination was 3.44 mm for E. wolfii and 4.17 mm for E. caroides. However, seeds of both species reached less than 50% final germination if subjected only to cold incubation. Higher final germination was possible if seeds were pre-treated with dry cold storage (-22 ºC) or exposed to GA3, indicating the existence of physiological dormancy (PD) in part of the seed population. Therefore, both species had non-deep complex morphophysiological dormancy (MPD). This study demonstrates that E. caroides and E. wolfii share the same germination requirements, suggesting a common ecological strategy in their seed germination process.