Final Germination Research Articles

Toxicogenetic effects are involved in the occurrence of imbibitional damage in soybean seeds

Soybean represents a valuable source of food for humans and animals and the quality of the seeds has great importance for the establishment and high productivity of this crop. Soybean seeds require continuous improvement, which is dependent on a better understanding of the regulatory mechanisms that coordinate seed germination. To investigate whether the method of water absorption into soybean seeds could lead to abnormal seedlings, and if this could be associated with cytogenetical consequences, we premoistened the seeds of three cultivars; M 6410 IPRO, M6210 IPRO, and BMX Potência RR by direct immersion (fast method), use of a wet substrate (intermediate method), and by moist atmosphere (slow method) with distilled water at 25ºC for 24 hours. We investigated the normal and abnormal seedlings, electrical conductivity, mitosis, cell death, and the chromosomal abnormalities index. The comet assay was applied to investigate DNA fragmentation. Direct immersion in water induced seedling growth inhibition and caused cytological alterations associated with genotoxicity effects in the studied soybean genotypes. Slow premoistening of the seeds increased seedling performance as a result of higher final germination percentage (above 85%), reduced abnormal seedlings (below 5%, on average), and reduced the electrical conductivity of seeds. All three genotypes of soybean seeds lost their ability to withstand the imbibitional damage induced by direct immersion as abnormal seedlings increased. We concluded that the fast water absorption by seeds poses a threat to genomic integrity owing to its potential for genotoxicity to DNA, manifesting as breaks or loss of whole chromosomes. Slow premoistening of the seeds resulted in a longer time period to deal with damage. Stabilized seedling growth was provided by altering cytogenetic responses during uptake of water by soybean seeds through the maintenance of cell viability.

GREEN SYNTHESIS OF ZINC OXIDE NANOPARTICLES USING SCHREBERA SWIETENIOIDES ROXB., AQUEOUS LEAF EXTRACT AND INVESTIGATION OF ITS EFFECT ON SEED GERMINATION AND PLANT GROWTH ON PIGEON PEA (CAJANUS CAJAN LINN.)

Objective: The present work intended to green and eco-friendly synthesis of Zinc oxide (ZnO) nano particles (NPs) using aqueous leaf extract of Schrebera swietenioides and the synthesised NPs were applied for enhancement of seed germination and plant growth in pigeon pea (Cajanus cajan Linn.). Methods: The Zinc acetate was utilised as metal source and metal was reduced using aqueous leaf extract of S. swietenioides as green reducing agent. The synthesised NPs were characterized using various techniques such as SEM-EDS, TEM, XRD, FT-IR and UV-visible spectrophotometer. The seed germination study as well as plant growth promotion activity, was performed on pigeon pea seeds. Results: The result achieved in characterization of NPs confirms that he NPs were hexagonal wurtzite form having a spherical shape with irregular surfaces. The average size was found to be 68 nm with the metal composition of 73.7 %. The NPs were studied for seed germination and growth promotion activity on pigeon pea seeds and the mean germination time was observed to be 38.60±0.56, 28.53±0.59 and 37.53±0.40 h whereas the final germination percentage was found as 91.33±0.58, 98.00±1.00, and 92.67±1.15 h for control, NPs treated and zinc acetate treated seeds respectively. The NPs treated plants grow more rapidly than the untreated as well as Zn acetate-treated pigeon pea plants. The pigeon pea seeds treated with ZnO NPs shows the high activity of enzyme activities such as amylases, protease, catalase than the untreated as well as Zn acetate treated seeds. Conclusion: The aqueous leaf extract of S. swietenioides mediated ZnO NPs can augment the growth of pigeon pea seedlings, and the NPs treatment shows a stimulatory effect on the enzymes associated with the growth of seedlings.

Differential Seed Germination Responses of Tomato Landraces to Temperature under Climate Change Scenarios

This study aims to quantify the seed germination response of six tomato landraces to temperature; predict future climate changes relative to the baseline period (1980–2009) for studied locations in the courses of near-term (2010–2039) and mid-term (2040–2069) under two representative concentration pathways (RCP 4.5 and 8.5); assess the impact of future climate change on the final germination percentage (FGP) and time to reach 50% germination (D50) in the studied landraces. The results show that FGP is zero at 10 °C, reaches the highest value at 15–35 °C, and ceases at 36–40 °C for all landraces. The results also demonstrate that the temperature increment is 0.8–1.3 °C and 1.5–2.7 °C in the near- and mid-term, respectively, under RCP 4.5; further, this increment is 0.9–1.9 °C for the near-term and 2.3–3.4 °C for the mid-term under RCP 8.5. It estimates that the D50 takes 2.5 to 3.8 days among the locations in the baseline course. In the near term, the D50 would be 2.2 to 3.4 days under RCP 4.5 and 2.1 to 3.3 days under RCP 8.5. For the mid-term, the D50 would be projected between 1.9 and 2.9 days under RCP 4.5 and 1.8 to 2.7 days under RCP 8.5. The FGP increases up to 19.5% for Gorgan and 21.3% for Varamin under climatic scenarios relative to baseline, and it will not change in the future climate for other landraces. In conclusion, global warming can result in rapid, uniform, and complete germination in different tomato landraces.

Effects of Hydro-priming and Seed Size on the Germination, Root, and Shoot of Peanut (Arachis hypogaea L. var. NSIC Pn18) Grown under Drought Conditions

This study aimed to assess the effects of hydro-priming duration and peanut seed size on the germination performance and the root and shoot characteristics of peanut seedlings under drought conditions. Two experiments were conducted under the laboratory and nursery. Peanut seed sizes (S1: small seeds and S2: large seeds) designated as the main plots, and duration of priming (P1: 0 hour, P2: 5 hours, and P3: 10 hours) was considered as the subplots. A 2 × 3 split-plot completely randomized design with three replications was used. Ten small and ten large seeds were placed in 4 × 4 inch plastic containers for laboratory experiment and 25 × 25 cm cellophane for pot experiment per treatment filled with dry soil at 10% moisture content. Large seeds soaked at 5–10 hours emerged earlier than the unsoaked seeds in this study. Final germination enhanced in bigger seeds also resulted in an increase in the germination index (seeds day−1) and the seedling vigor index. Likewise, larger seeds produced shorter shoots and plant height but broader shoots with more leaves. It is recommended that bigger seeds can be a good source of planting materials when planted in drought conditions and primed at 5–10 hours. However, unprimed smaller seeds can be used as planting materials in moist soil conditions. The interaction effect was noted on the fresh shoot weight of peanut plants as affected by seed size and hydro-priming. Higher fresh shoot weight of peanut plants when exposed to priming regardless of the seed size was obtained.

Stepping up to the thermogradient plate: a data framework for predicting seed germination under climate change.

Background and AimsSeed germination is strongly influenced by environmental temperatures. With global temperatures predicted to rise, the timing of germination for thousands of plant species could change, leading to potential decreases in fitness and ecosystem-wide impacts. The thermogradient plate (TGP) is a powerful but underutilized research tool that tests germination under a broad range of constant and alternating temperatures, giving researchers the ability to predict germination characteristics using current and future climates. Previously, limitations surrounding experimental design and data analysis methods have discouraged its use in seed biology research.MethodsHere, we have developed a freely available R script that uses TGP data to analyse seed germination responses to temperature. We illustrate this analysis framework using three example species: Wollemia nobilis, Callitris baileyi and Alectryon subdentatus. The script generates >40 germination indices including germination rates and final germination across each cell of the TGP. These indices are then used to populate generalized additive models and predict germination under current and future monthly maximum and minimum temperatures anywhere on the globe.Key ResultsIn our study species, modelled data were highly correlated with observed data, allowing confident predictions of monthly germination patterns for current and future climates. Wollemia nobilis germinated across a broad range of temperatures and was relatively unaffected by predicted future temperatures. In contrast, C. baileyi and A. subdentatus showed strong seasonal temperature responses, and the timing for peak germination was predicted to shift seasonally under future temperatures.ConclusionsOur experimental workflow is a leap forward in the analysis of TGP experiments, increasing its many potential benefits, thereby improving research predictions and providing substantial information to inform management and conservation of plant species globally.

Germination Performances of 14 Wildflowers Screened for Shaping Urban Landscapes in Mountain Areas

Despite the high biodiversity in the Mediterranean region, the use of wildflowers from mountain areas in urban landscaping projects is hampered by the limited information on their seed germination performances. This research evaluated germination traits of 14 native herbaceous wildflower species from northern west Italian alpine and subalpine areas. Seed germination in Petri dishes at 25 °C was performed, applying two different photoperiod conditions (light/dark at 0/24 h or 12/12 h). A high rate and rapid germination are key features for seed and seedling nursery production; thus, the main germination indices were evaluated: the final germination percentage, the index of germination relative to light, the time of first germination, the time to reach 50% of germinated seeds, the germination period, and the mean germination time. Overall, Bellis perennis L., Leucanthemum vulgare Lam., and Taraxacum officinale Weber, from mesophilic mountainous hilly grasslands, and Dianthus carthusianorum L. and Lavandula angustifolia Mill. from higher altitudes, turned out to be interesting. Particular attention could be paid to D. carthusianorum for germination synchrony in both growth conditions, high speed, and short germination period (8.5 and 16.2 days in the dark and in the light, respectively).

Biosynthesis of Nano-Selenium and Its Impact on Germination of Wheat under Salt Stress for Sustainable Production

Selenium and its derivatives have been found capable of excellent biological responses. However, the element in its bulk form has low bioavailability and increased toxicity, meaning the production of effective forms with sustainable methods has become urgent. Several microorganisms, including fungi, bacteria and yeast, as well as higher plants, are capable of biosynthesizing nanoparticles such as nano-selenium (nano-Se), which has wide applications in medicine, agriculture and industry. Thus, the biosynthesis of nano-Se using some bacterial species was the main target of this study. The production of nano-Se and the monitoring of its impact on the wheat germination of seeds under salt stress (i.e., 50, 100, and 150 mM NaCl) was also evaluated in the current study. The ameliorative role of nano-Se doses (i.e., 50, 75, and 100 mg L−1) in the germination of wheat seeds under salt stress was also investigated. Based on sodium selenite tolerance and reducing selenite to elemental Se-NPs, the most effective isolate (TAH) was selected for identification using the 16S rRNA gene sequence, which belonged to Bacillus cereus TAH. The final germination percent, mean germination time, vigor index and germination rate index were improved by 25, 25, 39.4 and 11%, respectively, under 15 mM sodium chloride concentration when 100 mg L−1 nano-selenium was used. On the other hand, the results obtained from a gnotobiotic sand system reveal that with treatment with 100 mg L−1 nano-selenium under high Ec values of 14 ds m−1, the vegetative growth parameters of shoot length, root length, fresh weight and dry weight were improved by 22.8, 24.9, 19.2 and 20%, respectively, over untreated controls. The data obtained from this study reveal that the use of nano-selenium produced by Bacillus cereus offers improved wheat seed germination under a salt-affected environment.

The Effects of Several Metal Nanoparticles on Seed Germination and Seedling Growth: A Meta-Analysis

Using the proper means to improve seed germination is of great significance in agriculture and forestry. Here, a meta-analysis was used to examine whether metal nanoparticle treatments have a specific effect on the seed germination and seedling growth of agricultural species. Using the Web of Science (1950–2021), PubMed (1950–2021), and Scopus (1950–2021) databases, a paper search was conducted using the following items (“nanoparticles” and “seed germination”, “nanomaterials” and “seed germination”) to filter the references in the title, abstract, and keywords of the published articles. The results indicated that nanoparticle (NP) treatments had a significantly positive effect on the final germination percentage (FGP), with a mean difference (MD) (that is, the overall effect) of 1.97 (0.96, 2.98) for the silver (Ag)-NP subgroup, 1.21 (0.34, 2.09) for the other-NP subgroup, 1.40 (0.88, 1.92) for the total based on the NP types, 1.47 (0.85, 2.09) for the “Concentrations: <50 mg/L” subgroup, and 1.40 (0.88, 1.92) for the total based on the NP concentrations. Similarly, root length (RL) was positively and significantly affected by NP treatment, with an MD (95% CI) of 0.92 (0.76, 1.09) for the zinc (Zn)-NP subgroup, 0.79 (0.65, 0.92) for the other-NP subgroup, 0.82 (0.72, 0.93) for the total based on the NP types, 0.90 (0.77, 1.04) for the “Concentrations: ≤50 mg/L” subgroup, 0.80 (0.60, 0.99) for the “Concentrations: >50 mg/L” subgroup, and 0.82 (0.72, 0.93) for the total based on the NP concentrations. However, there was no statistical correlation between the nanoparticle concentrations and shoot length (SL), due to the inclusion of zero in the 95% CI of the overall effect. Therefore, Ag-NPs could increase the FGP more than other-NPs, while Zn-NPs enhanced RL more. Moreover, NPs at lower concentrations could improve the FGP and RL of crop species to a larger extent than NPs at higher concentrations. This meta-analysis can provide a reference for the nanoparticle treatment technology utilization in agricultural and forest seeds.

Biological Control and Plant Growth Promotion by Volatile Organic Compounds of Trichoderma koningiopsis T-51.

Trichoderma spp. are widely used in plant disease control and growth promotion due to their high efficacy and multiple biocontrol mechanisms. Trichoderma koningiopsis T-51 is an effective biocontrol agent against gray mold disease by direct contact. However, the indirect physical contact biocontrol potential of Trichoderma spp. is not clear. In this study, the volatile organic compounds (VOCs) produced by T-51 showed high inhibitory activity against plant pathogenic fungi Botrytis cinerea and Fusarium oxysporum. The percentage of B. cinerea and F. oxysporum mycelial growth inhibition by T-51 VOCs was 73.78% and 43.68%, respectively. In both B. cinerea and F. oxysporum, conidial germination was delayed, and germ tube elongation was suppressed when exposed to T-51 VOCs, and the final conidial germination rate of B. cinerea decreased significantly after T-51 treatment. The VOCs from T-51 reduced the Botrytis fruit rot of tomato compared with that noted when using the control. Moreover, the T-51 VOCs significantly increased the size and weight of Arabidopsis thaliana seedlings. Twenty-four possible compounds, which were identified as alkenes, alkanes, and esters, were detected in VOCs of T-51. These results indicate that T. koningiopsis T-51 can exert biological control by integrating actions to suppress plant disease and promote plant growth.

Germination characteristics of three key species and their implications for vegetation restoration in northern China

Seed germination is a complex physiological process that can affect species establishment as well as vegetation restoration and dynamics; however, the germination characteristics of several key species used to combat desertification remain unclear. In light, temperature, and air humidity-controlled growth chambers, four different light treatments, five alternative temperature treatments, 11 levels of water potential, and five constant temperatures were set up to study the effects of light, temperature, and water stress on the completion of germination of Medicago sativa L., Astragalus adsurgens Pall., and Glycyrrhiza uralensis Fisch. The results showed that completion of germination of G. uralensis seeds occurred significantly less than that of M. sativa and A. adsurgens. Light intensity had no significant effect on the final germination percentage of M. sativa, A. adsurgens, and G. uralensis, but the germination rate under 100 and 400 μmol·m–2·s–1 light was significantly greater than that under 25 μmol·m–2·s–1. Temperature had no significant effect on the final germination percentage of these species’ seeds, and the germination rate was greater at 15/25 °C and 20/30 °C. The germination rate decreased as the water potential decreased. The germination results indicate that late spring is a suitable sowing time for G. uralensis to obtain optimal levels of completion of germination.

Physiological Aspects of Germination and Early Seedling Establishment of Pleurotus sajor-caju Glyceraldehyde-3-Phosphate Dehydrogenase Expressing Transgenic Rice in Saline Environment.

GPD encodes glyceraldehyde-3-phosphate dehydrogenase enzyme involved in sugar mobilization, particularly glycolysis and gluconeogenesis. The objective of this study was to determine physiological aspects of germination and early seedling establishment of PsGPD (Pleurotus sajor-caju glyceraldehyde-3-phosphate dehydrogenase) expressing transgenic rice (T5) against different salt concentrations. The T5 line that carried 2 copies of T-DNA and had the highest level of PsGPD expression was used in the investigation. Final germination percentage, amylase activity, reducing sugar accumulation, and chlorophyll biosynthesis were comparatively higher in PsGPD expressing transgenic rice against elevating saline conditions. A slow-paced conversion of porphyrin's precursors was seen through the matrix model and further elaborated by a graphical model. A sustained level of porphyrin was observed in PsGPD expressing transgenic rice. These data were concurrent with the relative gene expression and thermal imaging (thermography) of PsGPD expressing transgenic rice against salt stress. Morphological attributes also favored the salt tolerance exhibited by PsGPD-transformed rice.

Effect of oxygen on the germination and culturability of Bacillus atrophaeus spores

The effect of oxygen on the germination and culturability of aerobic Bacillus atrophaeus spores was investigated in this study. Under oxic or anoxic conditions, various nutritional and non-nutritional germinants were utilized to induce germination. Tb3+-dipicolinic acid fluorescence assay and phase-contrast microscopy were used to track the germination process. The final germination level, germination half time, and germination speed were used to define germination kinetics. Colony-forming unit enumeration was used to assess the culturability of germinated spores germinated with or without oxygen. The results show that in the absence of oxygen, the final germination level was unaffected, germination half time decreased by up to 35.0%, germination speed increased by up to 27.4%, and culturability decreased by up to 95.1%. It is suggested that oxygen affects some germinant receptor-dependent germination pathways, implying that biomolecules engaged in these pathways may be oxygen-sensitive. Furthermore, spores that have completed the germination process in either anoxic or oxic conditions may have different culturability. This research contributed to a better understanding of the fundamental mechanism of germination.

Effect of Plant Growth Promoting Bacillus spp. on Germination and Seedling Growth of Soybean

Background: Bacillus spp., known to promote growth and reduce disease of various field and vegetable crops, are frequently found in soils. The objective of the study was to select effective Bacillus spp. isolates with multiple plant growth properties and antifungal activities and to examine their effect on germination of soybean. Methods: Bacterial isolates were screened for production of indole-3-acetic acid (IAA) and siderophores and solubilization of phosphate. The ability of bacterial isolates to inhibit the growth of seven phytopathogenic fungi affecting soybean was determined using a dual plate assay. Bacillus spp. were further selected and examined in a seed germination test. Result: All Bacillus spp. isolates were positive for IAA production, while siderophore production and P-solubilization were observed in 80% and 20% bacterial isolates, respectively. Bacillus spp. exhibited the highest antifungal activity against Diaporthe caulivora, followed by Diaporthe sojae, Diaporthe eres, Diaporthe longicolla and Macrophomina phaseolina and the least antagonistic effect toward Fusarium graminearum and Fusarium subglutinans. Selected isolates of B. subtilis significantly affected final germination, shoot length, root length, shoot dry weight and root dry weight of two soybean cultivars. The most effective Bacillus spp. isolates could be used as potential inoculants for improving soybean productivity.

Germinability and Seedling Growth Performance of Chilli (Capsicum annuum) Seeds in Response to Different Gibberellic Acid Concentrations Pre-Treatment

Chilli seeds are always associated with physiological dormancy characteristics or endogenous dormancy that has affected their germination potential. Problems noticed on the low seed germination rate, vigour growth, further may lead to the poor seedling growth pattern of chilli crop production. Gibberellic Acid (GA3) which is usually used as a treatment solution is not a new advent of seed dormancy breaking methods for chilli. But, looking forwards to a better GA3 concentration is still needed for the discovery of this treatment potential effect on chilli seed germinability and seedling growth. Thus, this study aimed to evaluate the effect of different GA3 concentrations on seed emergence and seedling growth performance in chilli. In this experiment, chilli seeds were imbibed with 25 mg/L, 75 mg/L and 125 mg/L concentration of GA3 with three replications each; for 24 hours at room temperature (32±4°C) and the untreated seeds as a control. The data collection on final germination percentage was taken daily for 21 days after sowing. While the 15 germinated seeds were directly planted on the 5 polybags arranged in the net house of Junaidy Jonik Farm, Sabah, Malaysia. The experiment was arranged in a completely randomized design with three replications. Data were subjected to analysis of variance with SAS version 9.4 and the significant means were separated by the least significant difference test at P<0.05. Significant differences were observed in the seed germinability measured; germination rate index (GRI), mean germination time (MGT) and final germination percentage (FGP), as well as on seedling vigour index (SVI) between treated and control seeds. Conversely, plant height, number of internodes, number of leaves and fresh weight of seedlings showed no significant differences among treatments. It was concluded that the use of GA3 was able to enhance chilli seeds germinability and could display a better SVI than the control. It is recommended to use GA3 treatment at 25 mg/L of concentration, as it may give an advantage to both economic and biological importance in producing higher germinability and seedling growth performance in chilli.

Determination of salt tolerance levels and genetic relationships of Vicia sativa cultivars using gene targeted functional markers

The objectives of the present study were to determine salt tolerance levels of 12 different common vetch (Vicia sativa L.) cultivars at germination stage in the presence of 250 mM NaCl and to reveal genetic relationships based on gene targeted functional markers (GTFMs) associated with salt tolerance. The results revealed the presence of a significant genetic variation among the cultivars although s alt stress significantly reduced all germination parameters tested. The cultivar Ozveren was the most salt tolerant with 20.1% reduction in final germination percentage compared to control seeds while cultivars Alınoglu, Ayaz and Bakir did not germinate. The maximum delays in germination rate (G50 = 3.78 days) and synchrony (G10-90 = 3.45 days) were obtained from the cultivars Urkmez and Ozveren, respectively. The GTFMs provided a total of 53.1% polymorphism. The primers of MtSOS2 gene gave the highest numbers of alleles per primer pair while the highest polymorphism rate (77.8%) was obtained from the MtP5CS gene. The first three components of principal component analysis explained 57.63% of total variation. This study concluded that the cultivars determined to be salt tolerant and sensitive at germination stage distributed into three main clades determined by UPGMA analysis while the GTFMs associated with salt tolerance successfully determined the genetic relationships of common vetch cultivars.

Seed functional traits in cultivars of tall fescue (

Context Tall fescue (Schedonorus arundinaceus) is one of the most important cultivated forage grasses in temperate regions but its association with some Epichloë fungal endophytes usually makes it unsuitable for livestock feeding due to toxic alkaloids. However, re-inoculation of plants with non-toxic endophytes can result in positive effects for livestock feeding. Aims Assess the effects of the non-toxic AR584 endophyte on seed viability and germination in two tall fescue cultivars. Methods The effects of AR584 endophyte (presence/absence) and tall fescue cultivar (INIA Aurora/Taita) were evaluated on seed viability and germination responses across a range of temperature and water availability regimes. Response to constant temperature and water availability was characterised by the thermal-time and hydro-time models, respectively. Key results Under accelerated aging conditions, endophyte presence reduced seed viability in cultivar Taita. For both cultivars, endophyte-infected seeds showed a lower germination rate than endophyte-free seeds, except for INIA Aurora under low incubation temperatures. Also, endophyte-infected seeds in both cultivars displayed lower germination rates and final germination as the water potential was lowered. Conclusions A strong cultivar-by-endophyte interaction for seed germination indicates the need to understand how specific cultivar-endophyte combinations best fit a given environmental condition, as defined by temperature and water availability. Implications The information we present can be valuable not only for farmers who have to decide what to cultivate but also for seed companies that have to preserve seed quality.

Germination and Photosynthetic Responses to Salinity and Alkalinity in Avicenna marina Propagules

Avicenna marina (Forssk.) Vierh is a halophytic mangrove. The reproductive unit is green and has photosynthetic propagules. Mangroves are naturally exposed to fluctuations in some abiotic factors at the soil surface, including salinity and alkalinity. The objective of this study was to determine the effects of two salts including NaCl and NaHCO3 on germination processes and discuss the relationships between cotyledon photosynthesis and embryo axis growth in A. marina propagules. These propagules came from Al Birk, located on the shoreline of the Saudi Red Sea. The results showed that the studied salts did not affect neither the final germination percentage nor the embryo axis growth. However, rooting and root growth were delayed by both salts at 300 mM and were strongly inhibited by 600 mM NaHCO3. Both NaCl and NaHCO3 reduced the photosynthetic activity. These two salts did not affect the other photosynthetic parameters, including stomatal conductance, net transpiration, and intercellular CO2. Thereafter, the reduction in net photosynthesis was not related to any limitation of stomatal conductance. The early germination phase was independent of cotyledon photosynthesis, whereas rooting and root growth may be limited by reduced photosynthesis under NaCl and NaHCO3.

Florecimento precoce, dissimilaridade genética e agrupamento de cultivares de alface com sementes tolerantes à termoinibição

ABSTRACT High temperatures interfere with lettuce cropping. Thermoinhibition of seed germination and early flowering cause important losses for farmers. The objectives of this work were to evaluate the tolerance to early flowering, to verify the genetic dissimilarity and to select lettuce cultivars tolerant to seed thermoinhibition. 18 cultivars were evaluated. The number of days until the first anthesis was verified for early flowering. Regarding seed thermoinhibition, the first and final germination counting and germination speed index were evaluated, using temperatures of 20, 25, 30 and 35ºC. The analyses were performed immediately after harvest and after six months under storage. The genetic dissimilarity was obtained using the Tocher Graph optimization and hierarchical UPGMA methods. Regression models were adjusted, and curves’ clustering was performed by testing the identity of the models. Early flowering was observed in cultivars Floresta, Colorado, Grand Rapids, and Everglades. Cultivars showed genetic variability and are dissimilar regarding tolerance to thermoinhibition. By clustering the regression equations, it was possible to select thermoinhibition tolerant cultivars.

Novel approach to overcome limitations of humanure usability for farming

Disposal of humanure is a big challenge as well as has huge potential for farming. The major drawback of humanure is high levels of potassium, nitrogen, phosphorus, which enhance pathogenicity by degrading water quality which results in crop-causing cardiac problems. It also has a low level of organic contents and high levels of pathogenic fungus and bacteria affecting both crop and consumer. Trichoderma is a biocontrol agent known to have potential antimicrobial and antifungal activity against pathogens, which are also commonly present in humanure. Hence, the present study investigated treatment (8 days of incubation) of humanure with Trichoderma to find the effect on humanure’s limitations for farming use. Afterward, germination of seeds was done in the 4 mediums: (i) Soil, (ii) Untreated Humanure, (iii) Treated Humanure, and (iv) Untreated Humanure with Soil, to see the effects of treatment of humanure on crops compared to other samples. The study interestingly found that Trichoderma treatment reduced high levels of potassium and phosphorus in humanure from 610.6 to 244.5 (kg/ hectare) and from 103 to 98.56 (kg/hectare) respectively, while increased low-level organic matter (2% to 10.28%) and sulfur (for immunity) (34.51 to 276.54 unit) indicating its potential. Moreover, Trichoderma treatmentmediated reduction of potassium and phosphorus shall also be reflected in the reduction of germination rate because high levels of potassium and nitrogen in humanure promote the rate of germination. The study showed that Trichoderma treatment reduced germination rate in humanure i.e. coefficient of the velocity of germination from 75.68 to 72.22 units, germination rate index from 21.79%/day to 17.78%/day and final germination percentage from 73.1% to 66.2%; though these values were higher compared to soil, yet indicating the potential of Trichoderma treatment. In addition, the increase in electric conductivity by Trichoderma treatment demands optimization of the approach for farming. Summarily, trichoderma treatment stands as the novel and potential approach to overcome the limitation of humanure to balance nutrient levels to that of ideal soil contents and to reduce pathogenicity of humanure.

Effects of Temperature, Light and Salinity on Germination of Salsola crassa (Amaranthaceae) Seeds from Different Years

Salsola crassa is a halophytic plant species from the Amaranthaceae family. In this study we aimed to find out the effect of temperature, light, salinity, and age of seeds on germination ability of S. crassa. Seeds of the species were collected in 2013 and 2014, and seed wings which are known as perianth segments, were removed before the experiments. Both seeds from different years were germinated under the same conditions. Two temperature regimes at 5°C/16°C and 8°C/20°C were used under dark and daily photoperiodism at 12 h intervals for determination of the effects of temperature. Seeds were germinated under different NaCl concentrations. Seeds that did not germinate under saline conditions were taken into recovery and the viability of the seeds that did not germinate after recovery were tested with the Triphenyl Tetrazolium Chloride (TTC) test. As a result, photoperiodism positively influenced the germination rate (p<0.05) of seeds from both years. Even though an increase in salinity decreased the germination rate it can be said that S. crassa is an euhalophyte whose seeds can even germinate at 1800 mM NaCl. Although the age of seeds is an important parameter for seed germinability, there was not any statistically significant difference between the seed viability and final germination rates for the S. crassa seeds from 2013 and 2014.