Influence of post-maturation on the color of the seed coat of Ziziphus lotus (L.) Lam. and on their germination capacity

Seed of Caesalpinia bonduc L. is difficult to germinate due to the thick and hard seed coat. The research aims to evaluate various methods for breaking dormancy of C. bonduc seed. This study was conducted from December to January 2016 The way to break the dormancy were arranged in Completely Randomized Design. Eleven methods to solve the seed dormancy of C. bonduc were compared. The ways to break the dormancy were soaking in water with different temperatures. The temperatures were 30C for 0 hours, 5 hours, 10 hours, and 15 hours. Other techniques to break the dormancy were soaking in hot water at 10000C for 5 hours, 10 hours, and 15 hours. Warm stratification with 100% air humidity (RH) at 40C for five days, ten days and 15 days also included as treatments. The last method was seed piercing with a needle. The variables observed in this study were germination capacity, germination rate, epicotyl length, plant height, and root length. The results of this study showed that the 11 methods of breaking seed dorman cy significantly affected germination capacity, germination rate, emerging epicotyl, and plant height. Seed piercing classified as the most efficient method as indicated by the value of 100% in germination capacity, 1.43 in germination rate, 13.64 cm in plant height, and 6.16 cm in root length.0

The aim of the study was to confirm and compare efficiency of methods enhancing the vitality of Scots pine and Norway spruce seeds: soaking in water, cold stratification, additional moistening and incubation according to IDS method. The examined parameters included water content in the seeds, germination energy, mean germination time and germination capacity before the seed treatment, after its treatment by the tested methods and after drying. Results show that all the tested methods accelerate germination of seeds; cold stratification is the most efficient and recommended method for Scots pine and soaking of seeds in water is the most efficient and recommended for Norway spruce. The best results in spruce were also obtained with cold stratification (comparable with soaking in water) but the method is complicated, longer-lasting and more costly than soaking in water.

ABSTRACTThe effects of seed soaking with gibberellic acid (GA3) on germinability of conventional corn variety ‘Nongda 108’ and super sweet corn variety ‘Chaotian 3’ were investigated under deep-sowing condition. GA3 soaking significantly improved seed germination and mesocotyl elongation of both varieties under 10 or 6 cm sowing depth. The most significant promotion occurred at 0.175 g L−1 GA3 in ‘Nongda 108’ and 0.035 g L−1 GA3 in ‘Chaotian 3’. To further illustrate the physiological explanations, seed respiration was estimated from dehydrogenase activity test and oxygen-sensing test. Dehydrogenase activities of both varieties were dramatically promoted after GA3 soaking. Compared with water soaking, the dehydrogenase activity in 0.175 g L−1 GA3-soaked seeds of ‘Nongda 108’ and 0.035 g L−1 GA3-soaked ones of ‘Chaotian 3’ was increased by 15.4% and 78.8%, respectively. Oxygen-sensing test showed that increased metabolism time (IMT) critical oxygen pressure (COP) and relative germination time (RGT) were decreased while oxygen metabolism rate (OMR) and relative germination rate (RGR) were increased in GA3-soaked seeds, suggesting that exogenous GA-accelerated seed respiration. Our results suggested that seed soaking with exogenous GA3 was a simple and practicable method to improve deep-sowing tolerance during corn seed germination, and the significant promotions were attributed to vigorous respiratory metabolism.

King sago palm or sago cycas are the other name of Kangi palm ( Cycas revoluta ) sago palm has been used as an indoor and outdoor landscape plant for centuries. The present study was conducted to estimate the effect of different priming treatments on seed germination of sago palm ( Cycas revoluta L.) in the research area of Department of Horticulture PMAS, University of Arid Agriculture Rawalpindi, Pakistan. The Experiment consisted of ten treatments; the seeds without pulp were soaked in solution of 500, 750 and 1000 ppm GA 3 and 2%, 3% and 4% solution of KNO 3 for 24 hr at room temperature. In case of hot water treatment, seeds were primed at 80 o C, 90 o C and 100 o C for 30, 20 and 10 minutes respectively. The effect of different concentrations of gibberellic acid (GA 3 ), potassium nitrate (KNO 3 ) and hot water on various parameters like germination rate, germination percentage, germination value, decayed seed percentage, time of germination, number of leaves and seedling height were studied. Significant results of germination rate (55.56 days), germination value (192.19) were achieved from 500 ppm GA 3 . Maximum germination percentage (73.33%) and number of leaves (2) were observed in KNO 3 at 2% followed by 500 ppm GA 3 . Similarly lowest decayed seed percentage (26.66%) and time of germination (59.41 days) were noted in 2% KNO 3 . The seedling height was optimum (19.33 cm) in 3% KNO 3 followed by 2% KNO 3 . Best germination results were obtained due to permeability of hard seed coat made by low concentrations of priming treatments (KNO 3 @ 3%).

Increased Germination through Pregermination Treatments of Chinese Pistache Seeds

The response of six sugar beet genotypes (Raspoly, Nada, Strube, Almaz, Toro, Oskarpoly) under seven salinity levels (distilled water as control, 1500, 3000, 45000, 6000, 7500 and 9000 ppm NaCl) and soaking in gibberellic acid levels were studied on germination parameters. An experiment with factorial arrangement was conducted by using randomize complete block design with four replications. Seed soaking in GA3 significantly affected final germination percentage (FGP), mean germination time (MGT), coefficient velocity (CV), seedling vigor index (SVI), energy of germination (EG), emergence rate (ER) and speed of germination (SG). Highest averages of FGP, CV, SVI, EG, ER and SG, were produced from soaking seed in 200 ppm of GA3. Moreover, highest averages of MGT were recorded from soaking sugar beet seed in the control treatment. Sugar beet cultivars significantly differed in FGP, MGT, CV, SVI, EG, ER and SG. Highest averages of FGP, MGT, CV, SVI, EG, ER and SG were recorded with sown Raspoly cultivar. Increasing salinity concentrations from 0 to 9,000 ppm significantly decreased FGP, CV, SVI, EG, ER and SG. While, MGT increased with increasing salinity concentrations. Results of means comparison showed that in all genotypes, there was a decrease in germination percentage due to salinity stress increment and maximum germination percentage was delayed. The interaction between cultivars and seed soaking in GA3 levels significantly affected FGP, MGT, CV and SVI. The interaction between seed soaking in GA3 levels and salinity concentrations significantly affected FGP, MGT and SVI.

In order to estimate the germinative performance of seeds of medicinal plants an experiment was performed with a pretreatment of seeds in vitro culture. The effect of pretreatments (Soaking in water and sulfuric acid ’’SA’’) on the GC and in vitro germinative performance of the seeds of fourteen medicinal plants namely: Nigella sativa, Lupinus mutabilis, Ricinus communis, Glycine max, Peganum harmala, Lepidium sativum, Hyoscamus muticus, Petroselinum crispum, Anacyclus valentinus, Ajuga iva, Salvia hispanica, Sesamum indicum, Eruca sativa and Portulaca oleracea were studied.The seeds of the plants studied are germinated in the soil firstly and in a Murashig and Skoug (MS) culture medium. Germination performance (germination capacity’’GC’’ and germination rate’’GR’’) were measured for each treatment. The results obtained showed that the pretreatments make it possible to demonstrate the germination, and to determine the optimal pretreatments for each species studied. L. sativum, E. sativa, R. communis, N. sativa, H. muticus, P. harmala, P. crispum are germinating species easy in the soil, while L. sativum and P. harmala, N. sativa, L. mutabilis, R. communis are species that require pretreatment with soaking in water. While soaking in SA is necessary for germination of H. miticus and P. crispum. In MS culture medium, the best GR were observed for all seeds except A. valentinus, A. iva, P. harmala and S. indicum. The species studied showed a varied behavior with respect to pretreatments at the time of their germination.

Juniperus oxycedrus L. and Pistacia lentiscus L. are two taxa with a rigid or rigid enough structure caused by a solid pericarp resulting in a strong inhibition of the germination. The objective of this work was to test the effectiveness of certain pre-germinative treatments on the germination rate of the Juniperus oxycedrus and Pistacia lentiscus seeds with the aim of restoring perturbed ecosystems. In this context 180 seeds from each of the 2 examined species were tested in the laboratory (the number of repetitions is 5, to reach the degree of freedom 'ddl'). The seeds were divided into 4 groups of 20 seeds of each species and were treated as follows: 1) Immersion in the concentrated (95%) sulphuric acid (H2SO4) for 10, 30 and 60 minutes; 2) Mechanical scarification with a scalpel; 3) Soaking in hot water (at 100°C) for 30 seconds, 60 seconds and 2 minutes; 4) Cold stratification at 5°C for 24 hours. There is also a control group of 20 seeds representing each of the two species, which remained neutral. In the case of the Juniperus oxycedrus seeds the results showed that the germination rate improves after the mechanical scarification with a scalpel (92%), followed by the cold stratification with water (86%) and a treatment with a concentrated sulphuric acid for 60 minutes (82%). The seeds were treated with H2SO4 for 10 and 30 minutes, respectively, soaked in hot water; the control lot did not germinate. The germination rate for the Pistacia lentiscus seeds is 88% after the mechanical scarification and 84% after the cold water stratification. On the other hand, the treatment with H2SO4 or after soaking in hot water does not allow for the germination of these seeds. The same result is observed on the control group (0% for 30 days).

Utilization of seeds storage results in decreased plant productivity. The increase can be used by treating seeds before planting through the technique of invigoration. This purpose of the study is to assess the effectiveness of invigoration methods using polyethylene glycol (PEG 6000) and ultrafine bubbles (UFB) to improve viability and vigor of sengon seeds (Falcataria moluccana). Seed agieng using 96 % ethanol was carried out to obtain the diversity of seedlot viability as the materials for testing the effectiveness of invigoration treatments. A complete random design was used to test the effectiveness of 5 invigoration treatments, i.e., seed without invigoration treatment, soaking in PEG 6000 -0.8 Mpa, soaking in PEG 6000 -1.2 Mpa, soaking in UFB water injected by environmental air, and soaking in UFB water injected by oxygen 99 %, with soaking time is 24 hours for each treatment. Seed agieng resulted three classes of seed viability, i.e. 62 % (initial seed), 83 % (seed agieng for 30 minutes) and 57 % (seed agieng for 60 minutes). In the condition of seed germination before treatment (DBA) 57 % and DBA 62%, invigoration treatments were significantly affected on seed germination capacity, but not significantly different in DBA 83 %. The soaking treatment of UFB injected by oxigen 99 % was able to improve the germination parameters (germination capacity, germination rate, and vigor index) on the sengon seeds with DBA 57 %. For seeds with DBA 62 %, the soaking treatment in UFB injected by environmental air was provided the best germination capacity, T50, and vigor index. The treatment of UFB injected by oxygen 99 % was more effective to improve the seed with very low viability and vigor (DBA 57 %). In general, improving of seed viability and vigor is more effective by using UFB than PEG 6000.

Japanese Stewartia (Stewartia pseudocamellia (Maxim.)) is a species with outstanding landscape qualities, but is not widely available because reliable propagation protocols have not been developed, including procedures for overcoming seed dormancy. Three experiments were conducted to determine the warm and cold stratification requirements of Japanese Stewartia seeds. In the first experiment, seeds given a 3-day aerated water soak in 1 mM GA3, followed by 3 months warm moist stratification at 25C (77F) had greater germination 173 to 297 days after initiation of cold (7C, 45F) stratification than seeds given a 3-day aerated water soak and similar warm and cold stratification treatments. Final germination was 70%, but germination was not synchronous, it occurred over 172 days. In the second experiment, germination was low (less than 1%) for seeds given either 9 months cold moist stratification or 3 months warm moist stratification at 20C (68F) before 6 months cold moist stratification. Seeds given a 3-month warm moist stratification at an alternating 12 hr 20/12C (68/54F) cycles and 10 months cold moist stratification germinated from 30 to 93%, depending on mother tree. Germination was asynchronous, beginning after 150 days cold stratification and continuing for the next 165 days. In the third experiment, germination was not enhanced by a 3-day aerated water soak in either 1 mM GA3 or water, compared with seeds given no aerated water soak prior to cold moist stratification. Germination was greatest, 35%, for seeds given a 3-month warm moist stratification at 15C (59F) followed by at least 4 months cold moist stratification. However, germination was asynchronous. The results begin to identify the warm and cold stratification treatments that result in high germination.

Laboratory and field experiments were conducted to determine the effectiveness of various poison, preservative, and antibiotic treatments currently in common use in sediment trap work. Our results agree with previous reports that most biological activity in sediment traps can be inhibited by appropriate concentrations of formaldehyde, chloroform, or mercuric chloride. Sodium azide appears to be less effective at inhibiting biological activity, while antibiotics and salt alone are probably too ineffective for long‐term deployments. On the basis of laboratory experiments, effective concentrations when sustained throughout the deployment are 50% saturated chloroform, 37 mM formaldehyde, or 180 µM HgCl2. Our results also indicate, however, that the weight of swimmers (zooplankton which swim into the trap and die there from contact with the poison) collected in sediment traps is higher when more effective treatments are used. The presence of large numbers of swimmers can greatly affect the flux and composition of particulate organic matter collected in sediment traps and may decrease the effectiveness of the various treatments in inhibiting microbial activity in the traps.

The paper deals with the assessment ofthe influence ofthe length ofcold stratification period onthe germination parameters ofseeds ofwild service tree [Sorbus torminalis (L.) Crantz]. The germination tests (4 100 seeds) were conducted in two runs in 2020 and 2021; they were performed for three seed lots and three cold stratification periods (two, three and four months) before the testing of germination in each run. The values of germination energy and germination capacity were assessed, and the germination rate was computed. The results showed that the two-month cold stratification period has not been sufficient to overcome the dormancy of tested seeds. Regardless of the year in which the tests were conducted, seeds stratified for two months showed almost zero germination. For seeds treated with three- and four-month cold stratification, the germination percentage varied from ca. 5% to 32% and from ca. 13% to 46%, respectively. Our results basically correspond with findings reported in the reviewed literature. In 2020, the seeds subjected to four-month stratification performed significantly better than the seeds subjected to three-month stratification. However, in 2021, the seeds stratified for three months reached slightly better results. Four-month stratification also led to an increased percentage of prematurely germinated seeds during stratification. To conclude, the two-month period of cold stratification proved to be insufficient and at least three months of cold stratification are needed to obtain the adequate germination of seeds in subsequent laboratory tests.

Parkia biglobosa (African locust bean) is a versatile leguminous tree with high ecological, nutritional, and economic importance in Sub-Saharan Africa. However, seed dormancy caused by a stiff seed coat limits its propagation. Aim: This study investigated the effects of several pretreatment procedures on P. biglobosa germination and early seedling growth. Location and duration: The study was conducted at Njala University's Department of Forestry and Wood Science in Southern Sierra Leone. It took a total of 8weeks to observe seed germination and field data recording. Methodology: Seeds were subjected to four treatments: physical scarification with sandpaper (T1), soaking in hot water (T2), soaking in water at room temperature (T3), and untreated control (T0). A total of 400 seeds (100 per treatment) were sown in a randomized complete block design using loamy soil and river sand in equal proportion. Over an eight-week observation period, germination rates, emergence rates (ER), and emergence rate indices (ERI) were recorded and analyzed using chi-square tests. Results: The results showed that scarified seeds (T1) had the highest germination rate (75%), followed by room-temperature-soaked seeds (T3) at 64%, the control (T0) at 50%, and hot water-treated seeds (T2) at 27%. Although T1 had the highest ER, T3 had the highest ERI (32.92), implying faster and more uniform early seedling emergence. Statistical study revealed a substantial correlation between pretreatment type and germination outcome (χ² = 51.75, p < 0.001). Conclusion: The data indicate that physical scarification and soaking in water at room temperature are effective, low-cost strategies for overcoming seed dormancy in P. biglobosa, however hot water treatment may reduce seed viability.

Lithocarpus lepidocarpa Hayata seeds were collected in 30, Nov. 2003, and the seed were water selected to remove the hollow seed. After water selected, the seeds were cold stratification under 4℃, and showed after 2 months, 4 months, 6 months, and 8 months. Forty seeds were showed as control, 20 seeds were wounded and 30 seeds were de-shelled. Two months cold stratification increase germination vigor and germination rate (85%) than without cold stratification seed as Liu and Kuo (1999) done, and the germination rate of wounded seeds were the same as the seeds only cold stratification, but could germinated faster. More than 4 months cold stratification, the germination rate of not only control but also wounded seed were decrease, while the germination rate of de-shelled seed were no influenced by the duration of cold stratification and maintained the germination rate in 90-100%. The results show that the seed of Lithocarpus lepidocarpus Hayata has dormancy, which could removed after 4 cold stratification for two months, and has serious physical barrier for seed germination. The best germination condition of Lithocarpus lepidocarpa will be cold stratification the water selected seed more than 2 months and de-shelled, which the germination rate will more than 90%.

The seeds of Tilia miqueliana Maxim. exhibit deep dormancy, which is categorized as combinational dormancy. This study utilized a comprehensive treatment involving magnetic fields, gibberellin (GA3), and cold stratification to promote the release of seed physiological dormancy and enhance germination rates. After being soaked in 98% H2SO4 for 15 min, mature seeds of Tilia were exposed to magnetic field treatments (150 MT, 250 MT) for different durations (25 min, 45 min, 65 min, and 85 min), as well as GA3 solution soaking (concentration: 0 μmol·L−1, 1443 μmol·L−1). Subsequently, cold stratification (0–5 °C) was applied to investigate the effects of these treatments on seed dormancy release and nutrient transformation. The results indicated that the comprehensive treatment involving magnetic field, GA3 solution soaking, and cold stratification effectively released the physiological dormancy of Tilia seeds and improved germination rates. Among the treatments, M150T85G1443 (magnetic field intensity: 150 MT, magnetic field treatment time: 85 min, GA3 soaking concentration: 1433 μmol·L−1) exhibited the most favorable outcome. After 75 days of cold stratification following the comprehensive treatments, the germination rate of M150T85G1443 seeds reached 89%. Additionally, the levels of storage substances such as starches and crude fats within the seeds decreased, while the utilization of soluble sugars and soluble proteins increased. The M150T85G1443 treatment exhibited the highest degree of variation, leading to gradual increases in metabolic activities of the seeds and a transition from dormancy to germination.