Higher Germination Research Articles

Effect of intraspecific seed trait variation on the germination of eight tropical dry forest species

Functional traits can have intraspecific and interspecific variations essential in the structure and dynamics of natural communities. These traits may have implications in the germination and seedling establishment phases in seeds. The objective of this study was to evaluate the effect of variations in mass, volume, and nutrient content (C, N, and P) on the germination of eight species representative of the tropical dry forest (TDF). Our results showed that seed size, both in terms of mass and volume, did not predict germination rates or percentages, nor were they related to nutrient content. In contrast, N content was the most important trait in the germination phase. Larger seeds did not germinate more or faster, but they could offer better resistance against desiccation, since they had higher C/N ratios in their tissues, a characteristic of orthodox seeds. The species A. guachapele, B. arborea, H. crepitans, and V. tortuosa presented a high biological potential in terms of their regeneration capacity, particularly, because the characteristics of their seeds, as well as the nutrient content, revealed consistent implications in their reproductive success, promoting high germination percentages in less time. In general, the results obtained in this study provide basic knowledge for future research, offering starting points for further exploration of species-specific adaptations and how they may be affected by the environment.

Genetic study for seed germination and shattering in Euphorbia lagascae in response to different seed treatments

Euphorbia lagascae Spreng is a promising emerging oilseed crop, with its seed oil accounting for approximately 50% of the seed weight. Euphorbia oil contains a significant amount of vernolic acid, comprising two-thirds of its composition, which boasts various industrial applications, including acting as a stabilizer-plasticizer and natural dye. However, this species was known to have a high degree of seed-shattering and a low germination rate, which act as two important barriers to large-scale production and exploitation. Therefore, the objective of this study is to determine the genetic control of seed germination and seed-shattering traits in order to develop a reliable pipeline that would be applicable for industries and breeders to select superior E. lagascae lines and design a robust breeding scheme in a short time at reduced labor costs. For this objective, five different wild-type genotypes of E. lagascae that demonstrated high germination potential were crossed with an ethyl methanesulfonate (EMS) mutant genotype that produces non-shattering capsules. The F2 populations from two successful crosses (A and B) were separated into three different treated groups for seed germination evaluation and to study the segregation of 200 individuals per F2 population. The three treatments were: light, gibberellic acid (GA3), and control treatment. Consequently, plants treated with approximately 250 μmol/m2/s of light showed significant improvement in germination up to 75% in cross A and 82.4 % in cross B compared with the control plants and the group treated with 0.05% GA3. According to the chi-square test results, the inheritance pattern of seed germination in response to light treatment follows a 3:1 segregation ratio between germinated and non-germinated seeds, indicating a dominant gene action in the F2 generation. The same conclusion was followed for the shattering trait in the group treated with light, which was also simply inherited as a 3:1 ratio for shattering vs. non-shattering capsules. Our results emphasize the importance and significance of light treatment in producing uniform populations through acceptable germination and shattering resistance of the mutant genotypes of E. lagascae. This is the first report of light treatment that significantly improved seed germination of E. lagascae, which may enhance efforts in the development of this new industrial crop as a feedstock for vernolic acid production.

New Insights for Promoting the Plant Growth and Germination and Applications in Agriculture

Drought is a generally prolonged period of dryness which creates significant damage to crops and prevents their effective growth. It can also refer to a prolonged period of extremely low precipitation, especially one that has a negative impact on growing or living conditions. Drought affects plants vary, depending on the various stages of the plant's growth and the duration, severity and frequency of the drought. During high concentration germination decreases with increasing level of drought. Water deficiency also reduces the dry biomass of seed and seedlings. Drought stress causes the decline in seedling of wheat. The field experiment was conducted by utilizing augmented block design. Augmented block design is used when a limited quantity of resources available for experiment. From upper position of the spike excluding awns to the soil surface in centimeter were noted before harvesting. Spikes from each plot were selected randomly and number of spikelets was counted starting from base of spike towards the spike end. Under drought, plant height, spikes, peduncle length of selected plants was affected and had significant differences during normal irrigation and rainfed conditions. Grain yield per plant had highly significant positive correlation spike length under water irrigation.

INOCULAÇÃO COM AZOSPIRILLUM BRASILENSE, TRICHODERMA HARZIANUM, BACILLUS SUBTILIS E BACILLUS MEGATERIUM EM SEMENTES DE MILHO

The aim of this study was to evaluate the effects of inoculation and coinoculation with the microorganisms Azospirillum brasilense, Trichoderma harzianum, Bacillus subtilis, and Bacillus megaterium on seed germination and on maize production components. Two experiments were carried out, the first in the laboratory and the second in the field. Experiment 1 was carried out in a completely randomized design (DIC) with eight treatments and four replications of 20 seeds. Pioneer® cultivar 30F53 was used. For inoculation and co-oculation, BiomaMais®, StimuControl® and BiomaPhos® products were used, the seeds were placed in plastic bags and the doses of each treatment were added to it. The dose used was 80 ml ha-1 of Azospirillum brasilense; 92 ml ha-1 of Trichoderma harzianum and BiomaPhos® product. These were placed on moistened Germitest® paper 2.5 times the weight of the paper and kept in a germination chamber. After seven days, germination, shoot and root length were evaluated. To evaluate the emergence speed index (IVG), 50 corn seeds were sown with the treatments on three sheets of Germitest paper, the same procedures being carried out in the germination test. Experiment 2 was carried out in a randomized block design (DBC), with eight treatments and three replications of 40m². Corn sowing was carried out in the conventional system. A spacing of 45 cm was used, with 4 rows each 20 m long, sowing of 3 plants m-1. Inoculation and co-inoculation followed the same procedure as in experiment one. Productivity components were determined. Treatment T5 resulted in higher germination and root length. Inoculation with T3 resulted in greater development of the aerial part of the seedlings. The T8 treatment showed the highest grain yield.

Influence study of the seed germination multigerm pollinators of the sugar beet on their productivity

Goal. Studies conducted on Verhnyachskoy experienced-selection stations. Purpose of the studies was define the influence hereditary conditioned sign seeds germination new candidate in multigerm pollinators (МP) of the sugar beet on productive quality of the material. Conduct the selection perspective number posterity F1 and define efficiency of the selection on their improvement.
 Methods. Initial materials (IM) have served recombination (rk) МP foreign gene plasma productive rk БЗ4, БЗ5 БЗ6 БЗ7 and individual elections of their hybrids — synthetic, are received in result pollinate cross and have checked up crossbreeding, with high growing seed 80—95%. Standard — native pollinators Verhnyachkoy of an origin.
 Results. Phenologicheskie of supervision, laboratory germination seeds and test of a grade carried out in the standard methods [1, 2]. It is installed that high seeds germination have inherited the posterity under number 547, 556, 563, 564 (93—96%). We tie this as with weather condition under grow seeds so and ingenious selection component crossbreeding. Beside them is fixed satisfactory factors on productivities (45.3—50.3 t/h) in comparison to IM (42 t/h) and standard (38 t/h). Contents sugar from 19.51—20.21%, standard has got 19.44. Collection sugar was within 9—10 t/h (standard — 7, IM — 8 t/h). Satisfactory posterity productivity, probably, have got not only as a result favorable climatic condition at years of the test, but also in greater degree they are inherited from high productivity of the source parental forms.
 Conclusions. Have got the row new candidate in MP with improvement selection- and economic-valuable sign. Is established, that at creation new seeds of parental components of hybrids of sugar beet, it is necessary to take into account parameters of the genetic control of attributes of productivity, contents of sugar in IM and high quality of efficiency seeds. This spurs the posterity on temple ease of manufacturing, competitive ability and profit.

The effect of parica seed water immersion time on the success of parica seed initiation (Schizolobium amazonicum Huber ex Ducke)

Parica culture has the potential to overcome problems in parica seed germination. One factor that influences the successful initiation of parica culture is the process of sterilization and pre-treatment in the form of breaking seed dormancy. This paper aims to analyze the effect of the immersion time of parica seeds on the germination rate of parica seeds. The explants used were parica seeds with a size of ± 2 cm. Seeds are given pre-treatment, the seeds are immersed in hot water at around 70°C for 10 minutes, the immersion time in hot water is 3, 6, 12, and 24 hours according to treatment. The variables observed were the first time the parica seeds germinated, the percentage of germinated seeds, the percentage of contamination (fungi, bacteria), and the percentage of browning. The results showed that the immersion time for pre-treatment affected the success of parica seed initiation, especially seed germination. The 3-hour immersion treatment used resulted in the highest germination of parica seeds (55%) and significantly differed from the germination rates in other immersion times. Based on the high germination rate and low level of contamination, this becomes prospectively to provide optimal in vitro parica germination.

Vermicomposting of Sludge from the Camp SIC Cité-Verte Wastewater Treatment Plant (Yaounde-Cameroon)

In Yaounde, as in most sub-Sahara African cities, wastewater management is a major concern. Through its national sanitation strategy, Cameroonian government takes many initiatives to improve the urban sanitation situation by constructing social housing, where wastewater treatment plants are integrated. However, their purification performance is often low and the by-products represent great risk factors. This paper focuses on preserving the health of the population, reducing environmental pollution, and improving soil fertility by vermicomposting sludge from the Yaounde Camp SIC Cité-Verte wastewater treatment plant. The methodological approach consisted of the characterisation of sludge, followed by the vermicomposting test. At the end of the 35-day process, the produced vermicompost was characterized, and its agronomic efficiency was tested on waterleaf (Talinum triangulare) cultivation. The Yaounde Camp SIC Cité-Verte wastewater treatment plant consistently produces an average of 239 Kg of sludge per day. The sludge is primarily composed of high carbonaceous material (53%) and contains essential nutrients for plant growth (NPK: 13%), along with pathogenic microorganisms and heavy metals in low concentrations. The characterisation of the vermicomposts obtained after 35 days showed a conservation of nutrients (NPK) concentration and a decrease in carbonaceous matter and heavy metals. Moreover, there was a complete absence of fecal pathogens in the vermicompost of the two setups. The agronomic efficiency of the vermicomposts on waterleaf was shown by a high germination rate (100 % for vermicomposts), a high number of leaves (28 ± 15), a deep green coloration of plants, a great plant length (17.3 ± 4.6 cm), and a large stem diameter (2.1 ± 0.4 cm). The NPK content (˃7%) indicates that the vermicompost produced can be used as an agricultural organic fertilizer.

Batı Anadolu'da Yayılış Gösteren Jurinea cadmea Alt Türlerinin Üreme Ekolojisi ve Canlılık Değerlendirmesi: Koruma ve Biyoçeşitlilik Üzerine Çıkarımlar

In this study, the reproductive capacity of endemic Jurinea cadmea subspecies, J. cadmea subsp. cadmea, and J. cadmea subsp. nifensis was investigated, focusing on pollen, stigma, seed viability, and seed germination. Plant materials were collected from natural populations in Western Anatolia (Nif Mountain, Bozdağ, Babadağ and Muğla Oyuklu Mountain) between 2017 and 2020. The tests employed in this study included the MTT (2,5-diphenyl tetrazolium bromide-thiazolyl blue) test for pollen viability, the Peroxide test for stigma viability, the TTC (2,3,5-triphenyl tetrazolium chloride) test for seed viability, and seed germination tests under different conditions, with and without pre-treatment (wet-cold stratification). The study revealed high viability of mature pollen, stigma, and seeds, indicating successful reproductive capacity. Seed germination experiments showed that most populations exhibited high germination rates in light conditions. After 30 days of stratification, seeds showed very low germination in light and dark conditions, but after 60 days at 4⁰C, Nif Mountain, Bozdağ, and Muğla Mountain (short) populations exhibited germination rates above 80%. However, Babadağ population showed low seed germination in light and dark conditions. This study has significantly contributed to our understanding of the reproductive biology of both subspecies.

Effect of Euphorbia hirta Leaf and Root Extracts on the Early Growth of Cucurbit Crops

The research investigates the allelopathic influence of Euphorbia hirta extracts on the germination and seedling development of various cucurbit species, including Bottle gourd (Sp. A), Winter melon (Sp. B), Ridged gourd (Sp. C), Sponge gourd (Sp. D), Bitter gourd (Sp. E), Snake gourd (Sp. F), Muskmelon (Sp. G), and Pumpkin (Sp. H). The experimental design incorporated the use of both aqueous and methanol extracts of E. hirta, applied at different concentrations, with distilled water employed as the control. The findings reveal that the methanolic extract of E. hirta significantly impedes both the germination process and the subsequent growth of seedlings for all cucurbit species tested. For instance, at 12 days post-treatment, control groups exhibited high germination percentages (78%, 90.67%, 95.33% and 90% for Sp. A, Sp. C, Sp. D and Sp. E, respectively), which drastically declined with a 20% methanol extract concentration (23.33%, 18.33%, and 17.67% and 18.33% for the same species, respectively). Similarly, shoot and root length measurements indicated that higher concentrations of both extracts suppressed growth, with methanol extract showing a stronger inhibitory effect compared to the aqueous extract. Interestingly, Lower extract concentrations occasionally boosted shoot growth, revealing a hormetic effect. This two-fold response, notably in Pumpkin and Snake Gourd, illuminates the complexity of allelopathic interactions. The study suggests E. hirta extracts could serve as eco-friendly herbicides, urging further research to isolate their active components. This could lessen synthetic herbicide use, promoting sustainable agriculture and environmental protection.

Seed germination and vegetative and in vitro propagation of Hieracium lucidum subsp. lucidum (Asteraceae), a critically endangered endemic taxon of the Sicilian flora.

Hieracium lucidum subsp. lucidum is a critically endangered endemic taxa of the Sicilian flora. It is a relict of the Tertiary period surviving on the cliffs of Monte Gallo (NW-Sicily). This research focused on finding the best protocols for seed germination and vegetative and in vitro propagation to contribute to ex situ conservation. Seed germination tests were carried out using constant temperatures of 15 °C, 20 °C and 25 °C in continuous darkness and an alternating temperature of 30/15 °C (16 h/8 h, light/dark). The seeds had no dormancy, and a high germination capacity (70-95%) was obtained at all tested thermoperiods. The possibility of vegetative propagation of the taxon was evaluated through the rooting capacity of stem cuttings treated or not treated with indole-3-butyric acid (IBA). All cuttings were treated with IBA rooted within 2 months, while only 50% of the untreated cuttings were rooted within a longer time. An efficient protocol for rapid in vitro propagation from leaf portions was developed. The response of explants was tested on hormone-free Murashige and Skoog (MS) basal medium and MS enriched with different types of cytokinins: 6-Benzylaminopurine (BAP) and meta-Topolin (mT) in combination with naphthaleneacetic acid (NAA) and 2,4-Dichlorophenoxyacetic acid (2,4-D) at the same concentration. The combination of mT (2 mg L-1) and 2,4-D (1 mg L-1) in the medium was the most effective and showed the highest percentage of callus induction and the mean number of regenerated shoots. The maximum rate of root regeneration and the maximum number and length of roots were obtained on hormone-free MS and MS enriched with IBA at concentrations of 1 mg L-1. From the results obtained, it can be concluded that H. lucidum subsp. lucidum can be successfully propagated using one of the tested techniques, subject to the availability of the material for reproduction.

Assessment of the Protective Potential of Inoculums and Metabolites of Rhizobacteria on Soybean (Glycine max) Seedlings against Bacterial and Fungal Pathogens.

Plant growth-promoting bacteria (PGPR), while generally considered to aid plant growth with the provision of nutrients, can also be used as biocontrol agents for plant pathogens. The study assessed the protective potential of inoculums and metabolites of plant growthpromoting rhizobacterial strains against bacterial and fungal pathogens on soybean seedlings. Inoculums and metabolites of 15 rhizobacterial strains were used for the study. Five pathogens (Alternaria sp., Aspergillus niger, Corynespora sp., Fusarium oxysporum and Xanthomonas campestris) were employed for the study. Four experimental setups: treated-only seeds, infected-only seeds, infected then inoculum or metabolite treated seeds, and infected then distilled water treated seeds. In the setup infected with Alternaria sp., final germination values of seeds in the presence of the respective inoculums showed no significant variation between the treated only and the infected then treated setup. In the case of seeds infected with Aspergillus niger, higher germination and vigor index values were observed in the treated-only seeds when compared with the infected then-treated seeds. For seeds infected with Corynespora sp., significantly lower germination and vigor index values were observed in the infected then-treated seeds than the treated-only seeds in the presence of the respective inoculums. With regards to setup infected with Fusarium oxysporum, significantly higher final germination and vigor index values were recorded for the treated only seeds when compared with the infected then treated setups. For the Xanthomonas campestris infected seeds, the majority of the infected then metabolite-treated seeds showed significantly lower final germination values when compared with the treated-only seeds. The study findings were able to establish the efficacy of some bacteria agents against economically important species of plant pathogens.

Antioxidants and polymer coating for soybean [Glycine max (L.) Merr.] seed longevity enhancement

IntroductionTo explore the effect of polymer coating and antioxidants on the soybean seed quality enhancement by reducing the oxidation process, the experiment was carried out in the Department of Seed Science and Technology, PJTSAU, India. Method: Soybean seed of JS 335 was treated with four antioxidants at concentrations of 100 ppm, 300 ppm, and 500 ppm, either individually or in combination with polymer at 8 ml kg-1 seed and stored in airtight containers. Seed quality parameters like seed germination, seedling abnormality, seed mortality, seedling length, seedling dry weight, and Seedling Vigour Index 1 and 2 were measured at various months of storage period. Results: Polymer coating, either individually or in combination with antioxidants, showed a significant influence on soybean seed quality and longevity. Six months after storage, seeds treated with polymer + ascorbic acid at 100 ppm recorded significantly (p < 0.05) higher germination %, speed of germination and field emergence % (92, 40, and 85), followed by polymer + ascorbic acid at 300 ppm with a high seedling vigour index-2 (86) compared to untreated control (86, 35, 79, and 76, respectively). Seed treated with tocopherol at 300 ppm + polymer recorded higher seedling length (cm) and seedling vigour index-1 (24.73 and 2258) than control (17.49 and 1709, respectively). Among chemical antioxidants, ascorbic acid, followed by tocopherol and reduced glutathione, showed a good effect on soybean seed longevity. Conclusion: Soybean seed quality could be enhanced either with a polymer coating or with a polymer + antioxidant coating with ascorbic acid at 100 and 300 ppm.

Diversity of Crithmum maritimum L. from Salento Coastal Area: A Suitable Species for Domestication

Crithmum maritimum L., known as sea fennel, is an aromatic halophyte typical of the cliffs and coastal areas of the Mediterranean Sea and Atlantic Ocean. Their phytochemicals have been of great interest in the food and pharmaceutical industry. In this work, we analyzed, by SPME/gas chromatography coupled with mass spectrometry, the chemical variability of C. maritimum accessions in terms of volatile organic compounds. C. maritimum seeds were collected from different coastal sites in Salento, Southern Apulia, Italy, and subsequently cultivated ex situ. Several volatile compounds produced by C. maritimum leaves were detected, and, among them, D-limonene was found to be emitted at high levels by plants of all accessions representing the main compound, while other monoterpenes were produced at low levels. Moreover, the phenylpropene volatiles dillapiol and apiol (designated together as (dill)apiol) were emitted at variable amounts with different accessions. The correlation among groups based on volatile compounds has been analyzed using hierarchical cluster analysis, which has revealed three main groups based on (dill)apiol presence and its total amount in the cultivated plants of different geographic origins, confirming intraspecies biodiversity. Moreover, we have evaluated the seed germination and seedling development of C. maritimum in controlled conditions. We found no dormancy and a high germination rate for all samples analyzed. The chemo-diversity evidenced in cultivated plants obtained from seeds collected at different locations on the Salento peninsula is probably related to variations in climate resulting from different exposures along the coast. These findings highlighted the importance of C.maritimum as a suitable candidate for cultivation because it can tolerate harsh conditions/stresses and also has a possible use besides food and pharmaceuticals and for the restoration of coastal environments.

Do winter and summer cohorts of the invasive weed Parthenium hysterophorus differ in seed germination and seedling growth?

AbstractThe highly invasive weed Parthenium hysterophorus flowers during both hot, humid summers and cold, dry winters in Nepal, yet it remains unknown if there are differences in seed germination and seedling growth during these contrasting seasons. We analysed seed germination and seedling growth of summer and winter cohorts of P. hysterophorus in Kathmandu Valley. Seeds were germinated at low (25/15°C) and high (30/20°C) temperatures, 12/12 h photoperiod and complete dark, and at different levels of water stress. Seedlings were grown in a greenhouse to determine biomass allocation and relative growth rate (RGR). Winter seeds had higher seed biomass than summer seeds, and both seed types germinated under complete dark and 12/12 h photoperiod. Summer seeds germinated at significantly lower rates and percentage than winter seeds at the low temperature, but this difference in germination was not present when summer and winter seeds were incubated at the high temperature. Winter seeds had higher germination (percentage and rate) and took a longer time to reach maximum germination than summer seeds at different levels of water stress. Seedling emergence of both seed types declined with increasing soil depth. Seedling RGRs were nearly equal (summer: 73 mg g−1 day−1, winter: 77 mg g−1 day−1). Biomass allocation to stem and leaves were similar in both cohorts but root biomass allocation was higher in the winter than in the summer cohort. Overall, the maternal environmental effect was moderate on seed germination, and weak on seedling growth. Lack of a pronounced difference in the germination and seedling growth of summer and winter cohorts of P. hysterophorus suggests a wide environmental tolerance of the species, and this could be one of the reasons for the species' ability to invade diverse climatic and geographic regions globally.

Soybean planting date and seeding rate effect on germinability and vigor of harvested seed

AbstractSeed is one of the most crucial inputs for soybean [Glycine max (L.) Merr.] production due to its influence on plant population, uniformity, and yield, as well as its cost as an input. Seeds of good quality have high germinability and vigor, providing an adequate stand with uniformly good growth and development even under adverse conditions. This study aimed to measure the effect of soybean planting date and seeding rate on harvested seed mass, seed germinability, and seed vigor. Seeds were collected from a field experiment during the 2020 and 2021 growing seasons at two locations in Ohio: Western Agricultural Research Station and Northwest Agricultural Research Station. The study was conducted using a split‐plot randomized complete block design (planting date–whole plot; seeding rate–subplot) with four replications. Standard germination and accelerated aging tests were conducted in the laboratory using seeds harvested from the field study. All four site‐years demonstrated that planting soybean very late (June 16–July 1) produced lower weight seeds than the other planting dates. Across planting date and seeding rate treatments, the harvested seed germinability was ≥94%. However, soybean planted in early June (June 1–June 15) had the lowest seed vigor results (64%–81%) compared to other planting dates (80%–89%). Rainfall at R7–R8 development stages is negatively correlated with the seed vigor. The results will help seed producers optimize seed production and quality and suggest avoiding planting in June to increase harvested seed vigor.

Performance and mechanisms of alkaline solid waste in CO2 mineralization and utilization

CO2 mineral sequestration using alkaline solid waste (ASW) is a promising strategy for synergistically reducing CO2 emissions and reusing industrial waste. However, improvement the carbonation degree still remains challenges due to the sluggish leaching rate of Ca/Mg ion at low pH. To the issues, this study proposed an amine-mediated CO2 absorption and mineralization process with six common ASWs, as well an ecological utilization route of CO2-ASW productions. Experimental results indicated that calcium carbide slag (CS) had greater CO2 mineralization capacity (86.2 g-CO2/kg-CS) than other ASWs, while stirring rate and particle size played a more important role during CO2 capture. Amine-mediated CO2 capture was verified to be more excellent with steel slag (SS) as mineral medium. When the MEA concentration was increased to 2 mol/L, the extraction efficiency of Ca2+ was increased by 35 %, leaded to the CO2 removal efficiency significantly promoted from 49 % to 92 %. The characterization of structural morphology referred spherical aragonite or needle-bar calcite was dominant for the porous mineralization products (30.6 m2/g). High germination index of pea seed (112.1 % at a dose of 10 g/L) inferred the negligible toxicological effects of tiny MEA residue over SS mineralization products, after centrifugally washing treatment. Pea seeds cultivated with mineralized products after centrifugal washing can achieve a growth rate of about 4 mm/d. Overall, this work provides a feasible route to apply the porous CO2-ASWs production into water conservation in arid and sandy land.

Presowing Mechanical Seed Treatment Influencing the Emergence and Primary Seedling Vigor of Jujube (Ziziphus mauritiana Lam.)

Rootstock preparation from seed is the prerequisite for fruit crop multiplication through grafting or budding, and hard seed coat in jujube has been the proven question for uniform seed germination and subsequent seedling growth. Therefore, the study aimed at successful and rapid production of uniform and healthy jujube rootstocks through applying mechanical seed priming at the presowing stage. The experiment was set in a randomized complete block design where scrapped seeds, cracked seeds, seed kernels, and intact seeds (control) were sown in polybags keeping five replications. The emergence and initial seedling growth were evaluated to sort out the best pretreatment methods for successful stock seedling production in jujube. Seed cracking resulted in the highest germination (69.00%) compared to other pretreatments and also showed better performance in respect of earliness of emergence (10.40 days (d) for the first emergence and 20.40 d for final emergence). Regarding the early plant vigor, significantly maximum seedling height (23.73 cm) and fresh (3.91 g) and dry weight (1.17 g) of seedling and the second‐best leaf number (14.24 seedling−1) were also noted in seed cracking. Although seed kernel had the fastest emergence in 7.20 d, and statistically similar seedling vigor with that of cracked seed but it possessed very low germination percentage (27.00%) compared to the best treatment. Meanwhile, seed priming by scrapping exhibited statistically inferior germination rate (32%) as of intact seed (21%), and below par seedling growth compared to cracked seed. So, seed pretreatment by cracking can be suggested for commercial stock plant regeneration in hard seed‐coated plant species.

Improving semi-arid agroecosystem services with cover crop mixes.

Winter wheat (Triticum aestivum, L.) production in the semi-arid US Northern High Plains (NHP) is challenged by frequent droughts and water-limited, low fertility soils. Composted cattle manure (compost) and cover crops (CC) are known to provide agroecosystem services such as improved soil health, and in the CC case, increased plant diversity, and competition with weedy species. The main concern of planting CC in winter wheat fallow rotation in regions that are more productive than the NHP, however, is the soil moisture depletion. It is unknown however, whether addition of CC to compost-amended soils in the NHP will improve soil properties and agroecosystem health without compromising already low soil water content. The main objective of this study was to assess the effects of four CC treatments amended with compost (45 Mg ha-1) or inorganic fertilizer (IF) (.09 Mg ha-1 mono-ammonium phosphate, 11-52-0 and 1.2 Mg ha-1ammonium sulfate, 21-0-0) on the presence of weeds, soil and plant total carbon (C), nitrogen (N), and biological dinitrogen (N2) fixation (BNF). Mycorrhizal Mix (MM), Nitrogen Fixer Mix (NF), Soil Building Mix (SB), a monoculture of phacelia (Phacelia tanacetifolia Benth L.) (PH), and a no CC control (no CC) were grown in native soil kept at 7% soil moisture in a greenhouse for a period of nine weeks. When amended with compost, MM was the most beneficial (48 g m-2 BNF and 1.7% soil C increase). SB had the highest germination, aboveground biomass, and decreased weed biomass by 60%. It also demonstrated the second highest amount of BNF (40 g m-2) and soil C increase by 1.5%. On contrary, IF hindered BNF by almost 70% in all legume-containing CC treatments and reduced soil C by 15%.

Avaliação da viabilidade do pólen em algumas variedades de crisântemo em spray no período de armazenamento

Abstract In producing chrysanthemum hybrids, more seed sets per fruit are preferred. Only successful pollination and fertilization allow seeds to de-velop. High pollen viability and pollen germination rate are intimately correlated with successful fertilization. Chrysanthemum pollen and their storage duration have only been the subject of a relatively few investigations. The study aimed to determine pollen's viability and germination during the 4 days, which were kept at 24 ºC. In the present study, two different Chrysanthemum species (Chrysanthemum coronarium L. and Chrysanthemum segetum L.) and two commercial Chrysanthemum varieties (Chic and Haydar) that belong to Chrysanthemum morifolium Ramat. species as spray chrysanthemum pollens were used for experimental material. The grains pollen were stored in an incubator which was 24 ºC and 60% humidity. The pollen viability was tested with TTC (2,3,5 Triphenyl Tetrazolium Chloride) staining test and pollen germination was evaluated hanging drop method with modified ME3-m medium, daily for 4 days including day 0. The results showed that the viability and germination of all pollens used in this study decreased day by day. Depending on the species/varieties, the viability rates ranged from 12.83% to 32.04% on the first day and between 0.57-2.33% on the last day. Pollen germination rates differed between 16.76% - 3.45% on the 0th day and 0.0-0.17% on the 4th day.

Effect of temperature, light, seeding depth and mulch on germination of Commelina benghalensis and Richardia brasiliensis.

One of the major limitations to proper weed management is the lack of knowledge about the biology of the species. The aim of this study was to understand the influence of temperature and light on the germination and emergence of Commelina benghalensis and Richardia brasiliensis, as well as the influence of burial depth in the soil and the presence of mulch. The experiment regarding the influence of light and temperature on germination was conducted using a 2x4 factorial design, with two light conditions (presence for 12 hours and absence for 24 hours) and four temperature alternations every 12 hours (20-25 ºC, 20-30 ºC, 20-35 ºC, and 15-35 ºC), with four replications. The second experiment was conducted in a completely randomized design with four replications, testing seven sowing depths (0.0; 0.5; 1.0; 2.0; 4.0; 6.0; 10.0 cm) in clay-textured soil. In the third experiment, millet, black oat, and sun hemp straw were placed on the surface of the pot where the weeds were sown. R. brasiliensis showed high germination rates at 15°-35°C and in the presence of light, indicating positive photoblastism, as the germination percentage was 63.50% in the presence of light and 1% without light. C. benghalensis showed higher germination rates at 20-35ºC, with a germination percentage of 46.5% under light treatment and 44% in the absence of light. R. brasiliensis exhibited the highest germination percentage at a depth of 0.5 cm, with 72.50%. C. benghalensis showed better germination at depths of 1 and 4 cm, with 48.33% and 49.16%, respectively. Both crotalaria and millet caused significant inhibition of germination in both weed species. R. brasiliensis and C. benghalensis exhibit higher seed germination under alternating temperatures, with R. brasiliensis displaying positive photoblastism and C. benghalensis being neutral. Greater seeding depths negatively influence germination, and cover crops such as crotalaria and millet can be used to suppress these weeds.