Mean Germination Rate Research Articles

Determination of Germination Parameters of Safflower (Carthamus tinctorius L.) Cultivars Under Salt Stress

The present study was carried out to characterize germination capacity of 10 safflower cultivars under saline conditions. Five salt (NaCl) levels (0, 60, 120, 180, 240 mM) were used to test safflower seeds. Germination of seeds was counted every day for 14 days and germination percentage, Timson’s germination index, mean germination time, mean germination rate and germination stress index were calculated. Cultivar and salinity treatments were important for all parameters; however mean germination time and mean germination rate interactions were not important. Germination percentage, Timson’s germination and germination stress indices decreased significantly with increased salt concentrations. However, mean germination time increased with higher salt concentrations. The most significant reductions in germination percentage were observed at 180 and 240 mM salt concentrations. Correlation coefficients were all important for germination indices. Based on germination indices, Leed and FO2 were more sensitive to salt stress at germination stage and Royal was more resistant than the other cultivars tested. Germination percentage, Timson’s germination index and germination stress index were better to assess germination capacity of safflower cultivars under salt stress conditions. Mean germination time and rate were not suitable to assess differences in germination parameters of the cultivars under stress conditions.

Haplotype Analysis of BADH1 by Next-Generation Sequencing Reveals Association with Salt Tolerance in Rice during Domestication.

Betaine aldehyde dehydrogenase 1 (BADH1), a paralog of the fragrance gene BADH2, is known to be associated with salt stress through the accumulation of synthesized glycine betaine (GB), which is involved in the response to abiotic stresses. Despite the unclear association between BADH1 and salt stress, we observed the responses of eight phenotypic characteristics (germination percentage (GP), germination energy (GE), germination index (GI), mean germination time (MGT), germination rate (GR), shoot length (SL), root length (RL), and total dry weight (TDW)) to salt stress during the germination stage of 475 rice accessions to investigate their association with BADH1 haplotypes. We found a total of 116 SNPs and 77 InDels in the whole BADH1 gene region, representing 39 haplotypes. Twenty-nine haplotypes representing 27 mutated alleles (two InDels and 25 SNPs) were highly (p < 0.05) associated with salt stress, including the five SNPs that have been previously reported to be associated with salt tolerance. We observed three predominant haplotypes associated with salt tolerance, Hap_2, Hap_18, and Hap_23, which were Indica specific, indicating a comparatively high number of rice accessions among the associated haplotypes. Eight plant parameters (phenotypes) also showed clear responses to salt stress, and except for MGT (mean germination time), all were positively correlated with each other. Different signatures of domestication for BADH1 were detected in cultivated rice by identifying the highest and lowest Tajima’s D values of two major cultivated ecotypes (Temperate Japonica and Indica). Our findings on these significant associations and BADH1 evolution to plant traits can be useful for future research development related to its gene expression.

Effect of salinity on seed germination of some tomato (Lycopersicon esculentum Mill.) varieties

Salinity adversely affects 20-30% of the irrigated area in the world. Tomato is sensitive to salinity. It is one of the most severe abiotic factors of many agricultural crops and it becoming the main problem in Ethiopia. This study was conducted to evaluate the effects of different salinity levels on the seed germination parameters of tomato varieties. It was laid out in a completely randomized design with three replicates. The treatment included four tomato varieties (Sirinka, Weyno, ARP D2, and Roma VF) and five salinity levels (1 dS m-1, 2 dS m-1, 3 dS m-1, 4 dS m-1, and control). Fifty seeds were placed in a Petri dish over a moistened germination paper for germination and seedlings and allowed to grow for 14 days. The germination rate, speed and energy of tomato seeds were significantly (p &lt; 0.001) affected by the combined effect of variety and salinity. The shortest mean germination time, the highest mean germination rate, and the highest speed of germination were recorded in the ARP D2 variety in the control treatment. The lowest first and last days of germination, and the uncertainty of germination were recorded from ARP D2. However, an increase in the days of germination and in the uncertainty of germination, and a decrease in the germination index and total germination percentage trends were observed with increasing salinity levels. The highest level of salinity (4 dS m-1) affected the germination of tomato varieties. Among the four tested tomato varieties, ARP D2 and Roma VF were tolerant to salinity.

Fruit Ripeness Effects on Characteristics, Germination and Desiccation Tolerance of Syzygium myrtifolium Walp. Seeds

To plant Syzygium myrtifolium Walp. on harsh urban sites, planting materials of seed origin having better developed tap roots are preferred compared to those propagated from stem cuttings. However, fully ripe fruits at 8 weeks after fruit set are heavily lost to birds. In the current study, the unpalatable semi-ripe fruits at 7 weeks were found suitable for propagation. The seeds from the semi-ripe fruits showed mean germination rate of 93% and developed normal seedlings within 1 week, although continued growth with increases in size and fresh weight (FW) in the fruits and seeds was significant towards completion of fruit ripening. Thus, harvesting of fruits within the short period between these two fruit developmental phases is critical in the seed procurement process of this plant species. At the semi-ripe stage, pericarp exhibiting mixture of red and black colour can be a practical guide to indicate the suitable time for harvesting the fruits. Nonetheless, subsequent desiccation trial aimed to determine the storability of the seeds at postharvest found that the seeds obtained from both the semi-ripe and fully ripe fruits had drastic loss of germinability at seed moisture content of approximately 0.3 g H2O/g FW. Storage of the seeds above this relatively high moisture level for future planting was detrimental because the seeds age rapidly when they remain metabolically active with high respiration rates. Microbial infestation will also be an added problem during seed storage. Therefore, the seeds need to be sown fresh.

Effects of smoke water on germination, seedling vigour and growth of Sceletium tortuosum

Sceletium tortuosum (L.) N. E. Br. is a South African protected species widely utilized in traditional medicine. The plants' mesembrine-type alkaloids have immense potential in modern pharmacology as treatments for numerous medical and psychological disorders. Fresh plant material is paramount for researchers and pharmaceutical companies as it is presently the only available alkaloid source. Although S. tortuosum is a conservation concern and valuable to the pharmaceutical industry, information on germination behaviours of this species is scant. This study highlights the effects of the bio-stimulant smoke water (SW) on germination, seedling vigour and growth of Sceletium tortuosum in vitro. A standardized smoke extract was diluted to concentrations of 1:500, 1:1000, 1:1500, 1:2000, 1:2500 (v/v). Seeds were pulse-treated with SW solutions for 1, 2, 8 and 24 h. The study included positive and negative control treatments. The highest mean germination percentage and germination rate were recorded for 1:1000 SW for 24 h (83 ± 1.9%) and 1:2500 SW for 24 h (6.35 seeds germinated/day). Vigour index was highest for 1:1000 SW (24 h). Smoke water only improved seedling growth when germination occurred slowly. Although mean shoot length was optimal for 1:2500 (1 h) – 4.19 ± 0.15 mm – mean root length and seedling size were highest in the negative and positive (1 h) control treatments. This investigation showed that SW effectively improved germination and seedling vigour of S. tortuosum, however, alternatives must be investigated to optimize seedling growth when this biostimulant is applied.

EFFECT OF SEED PRIMING ON GERMINATION OF OKRA (Abelmoschus esculentus var. Arka Anamika)

Seed priming is an effective, eco-friendly method to promote seed germination and seedling vigor of okra to overcome the reduced and delayed germination in fresh or stored okra seeds caused by seed hardness. An experiment was carried to evaluate the effects of different priming on okra seeds germination and seedling vigor using Arka Anamika variety at Horticulture lab of Agriculture and Forestry University, Rampur, Chitwan, Nepal. Investigation was carried out with 6 treatments (T1: seed priming with tap water, T2: seed priming with 200ppm NAA solution, T3: seed priming with 10% PEG-200 solution, T4: seed priming with 200ppm GA3 solution, T5: seed priming with 5% Trichoderma solution and T6 no priming) with 4 replications in Complete Randomized Design (CRD). Seeds primed with T1 to T5 were soaked for 24 hours and shade dried for 6 hours before sowing. Priming with T4 was found to be best in terms of maximum seed germination (60.12%), seed vigor index (5772.68 cm), mean germination rate (7.53 seeds per day). The highest shoot length (81.40 mm) was observed at T1 whereas enhancement of root length occurred with the priming with T3. All treatments had a significant positive effect on all the germination parameters in comparison to control. The study concluded that GA3 priming enhanced germination as well as seed vigor in okra and hydro priming and tricho-priming can be used as an alternative to GA3 priming among farmers in Nepal.

Hydropriming Applied on Fast Germinating Solanum villosum Miller Seeds: Impact on Pre-germinative Metabolism.

Seed priming can circumvent poor germination rate and uniformity, frequently reported in eggplant (Solanum melongena L.) and its crop wild relatives (CWRs). However, there is still a gap of knowledge on how these treatments impact the pre-germinative metabolism in a genotype- and/or species-dependent manner. The CWR Solanum villosum Miller (hairy nightshade) investigated in this study showed a quite unique profile of fast germination. Although this accelerated germination profile would not apparently require further improvement, we wanted to test whether priming would still be able to impact the pre-germinative metabolism, eventually disclosing the predominant contribution of specific antioxidant components. Hydropriming followed by dry-back resulted in synchronized germination, as revealed by the lowest MGR (Mean Germination Rate) and U (Uncertainty) values, compared to unprimed seeds. No significant changes in ROS (reactive oxygen species) were observed throughout the treatment. Increased tocopherols levels were detected at 2 h of hydropriming whereas, overall, a low lipid peroxidation was evidenced by the malondialdehyde (MDA) assay. Hydropriming resulted in enhanced accumulation of the naturally occurring antioxidant phenolic compounds chlorogenic acid and iso-orientin, found in the dry seeds and ex novo accumulation of rutin. The dynamic changes of the pre-germinative metabolism induced by hydropriming are discussed in view of future applications that might boost the use of eggplant CWRs for breeding, upon upgrade mediated by seed technology.

Seedlings morphology of confectionery sunflower at different pH of water solution

In this study the confectionery sunflower seed was tested to germination at different pH media, from 3.5 to 8.5. The experiment was set up at room temperature (22°C) and at 24 h dark conditions for 10 days. The mean germination rate was 76%. The highest germination rate was 86% at pH 3.5, whereas the lowest was 68% at pH 5.5. The ANOVA resulted with very significant influence of pH on sunflower seedlings root, stem and total length (p&amp;lt;0.001). The total length of seedlings was the shortest at acid media (9.2 cm at 3.5) and the longest at alkaline media (12.5 cm at pH 8.5). Regression equitations showed that increment of stem or root length and total length have a positive trendline at all pH levels. It was found that the alkaline water solution has a positive influence on protein sunflower seedlings development, but it would be valuable to found how the seeds would germinate at the field conditions.

IMPROVING GERMINATION AND STAND ESTABLISHMENT OF KIWIFRUIT (Actinidia deliciosa cv. Hayward) SEED THROUGH MEDIA SELECTION AND HORMONAL USE IN DOLAKHA, NEPAL

This study was conducted at Boach, Bhimeshwor-8, Dolakha, Nepal from February to April, 2020 to analyze the effect of varied concentrations of gibberellic acid and growing media on germination of kiwifruit seeds. The experiment was done by using Factorial combination of four different concentrations: 0 ppm, 2000 ppm, 4000 ppm and 6000 ppm of gibberellic acid and different growing media: Peat moss, Cocopeat, Vermicompost and Normal Soil laid out in Completely Randomized Design (CRD); each treatment were replicated four times. Germination percentage, mean germination time, germination rate, mean germination rate, germination index, coefficient of velocity of germination and germination rate index were the parameters measured. The germination of kiwifruit seeds was significantly affected by gibberellic acid and growing media. The highest germination percentage (48.25%), germination rate (87.73%), germination index (0.88) and germination rate index (11.82) was recorded from seeds treated with 6000 ppm gibberellic acid and sown at peat moss whereas, the minimum germination percentage (13%), germination rate (23.64%) and germination index (0.24) was observed in seeds treated with 4000 ppm gibberellic acid and sown at vermicompost. The maximum time taken (46 days) to germinate was shown by seeds treated with 6000 ppm gibberellic acid and sown at normal soil whereas, the minimum time taken (35 days) to germinate was recorded in seeds treated with 6000 ppm gibberellic acid and sown at cocopeat. The highest mean germination rate (0.028 day-1) and coefficient of velocity of germination (2.79%) was observed in seeds treated with 6000 ppm gibberellic acid and sown at cocopeat whereas the least mean germination rate (0.022 day-1) and coefficient of velocity of germination (2.18%) was recorded in seeds treated with 6000 ppm gibberellic acid and sown at normal soil. From the findings of this experiment, it is revealed that the seeds treated with 6000 ppm gibberellic acid and sown at peat moss could be the most effective and appropriate to improve the germination and stand establishment of kiwifruit seeds.

The Hormonal Seed Priming in Relation to Carrot Germination

Seed priming is a pre-sowing treatment used to reduce stress effects in crops .This technique has been used to increase the germination rate of seeds mainly under unfavorable environmental condition. Crop productivity faces many problems like that unavailability of suitable condition that causes unbalanced seedling growth and poor germination. Hormones are essential to improve plant growth, development, crop yield quality and quantity. Auxin is essential hormones that improves germination of seeds and reduce stress effects. Laboratory experiment was conducted to study the effect of seed priming using different concentrations of IAA and IBA on carrot seeds (Daucus carota). In laboratory experiment, three concentrations of IAA and IBA (75 ppm, 50ppm, 25ppm) treated with distilled water with priming duration of 24 hours. Experiment was laid out in CRD with three replications. Data was collected to investigate the effect of seed priming with IAA and IBA under these condition like that (fresh weight, dry weight, speed of germination, root length, seed length, seedling length, final germination rate, mean germination time and dry matter content). Maximum fresh weight, final germination percentage, seedling length, energy of germination, speed of germination and mean germination rate was recorded IBA 75ppm. Maximum dry weight and dry matter content was observed IBA 25ppm.Maximum shoot length was recorded IBA 50ppm. Non-significant difference was recorded in root length.

Mitigation of Salinity Stress on Chickpea Germination by Salicylic Acid Priming

Salinity is a global problem that threatens chickpea (Cicer arietinum L.) cultivation in all stages from germination to maturity. Also, salt-affected areas in the World are increasing by the day. Germination is one of the primary stages affecting plant growth and seed yield. Thus, germination performance of seeds has a vital role in vegetative and productive stages. Seed priming, a cheap and easily applicable technique, improves the germination performance by regulating enzymatic reactions and controlling water intake. Seed priming is controlled hydration of seeds soaked in a solution that has low osmotic potential to start the germination metabolism without elongation of radical. The aim of the study was to investigate the effects of different priming treatments on germination traits of chickpea under saline conditions. Three levels of salinity (control, 50 mM and 100 mM NaCl) and 5 priming treatments (non-primed, hydro-priming, 0.1 mM, 0.2 mM and 0.3 mM salicylic acid) were used in the study. Germination percentage (GP), mean germination time (MGT), germination rate (GR), germination index (GI) and coefficient of uniformity of germination (CUG) were varied between 80.7-98.3%, 1.40-2.67 day, 38.1-75.7, 37.5-72.5 and 0.3-0.7, respectively. Although all treatments caused significant positive effects, the 0.2 mM SA mostly improved the germination traits in the study. Also, it was determined that 0.2 mM salicylic acid priming is the threshold for chickpea and higher concentrations have inhibitory effects on the germination process.

Magnetic Field (MF) Applications in Plants: An Overview.

Crop yield can be raised by establishment of adequate plant stand using seeds with high germination ratio and vigor. Various pre-sowing treatments are adopted to achieve this objective. One of these approaches is the exposure of seeds to a low-to-medium level magnetic field (MF), in pulsed and continuous modes, as they have shown positive results in a number of crop seeds. On the basis of the sensitivity of plants to MF, different types of MF have been used for magnetopriming studies, such as weak static homogeneous magnetic fields (0–100 μT, including GMF), strong homogeneous magnetic fields (milliTesla to Tesla), and extremely low frequency (ELF) magnetic fields of low-to-moderate (several hundred μT) magnetic flux densities. The agronomic application of MFs in plants has shown potential in altering conventional plant production systems; increasing mean germination rates, and root and shoot growth; having high productivity; increasing photosynthetic pigment content; and intensifying cell division, as well as water and nutrient uptake. Furthermore, different studies suggest that MFs prevent the large injuries produced/inflicted by diseases and pests on agricultural crops and other economically important plants and assist in reducing the oxidative damage in plants caused by stress situations. An improved understanding of the interactions between the MF and the plant responses could revolutionize crop production through increased resistance to disease and stress conditions, as well as the superiority of nutrient and water utilization, resulting in the improvement of crop yield. In this review, we summarize the potential applications of MF and the key processes involved in agronomic applications. Furthermore, in order to ensure both the safe usage and acceptance of this new opportunity, the adverse effects are also discussed.

Direct effects of nitrogen addition on seed germination of eight semi-arid grassland species.

Seed germination plays an important role in mediating plant species composition of grassland communities under nitrogen (N) enrichment. Shifts of plant community structure with N‐enhanced deposition in terrestrial ecosystems have occurred globally. Despite numerous studies about the effects of enhanced N deposition on mature plant communities, few studies have focused on seed germination. Using a laboratory experiment, we report the effects of five N concentrations, including 0, 5, 10, 20, and 40 mM N (NH4NO3) on seed germination of eight semi‐arid grassland species. Results showed that low N concentrations (5‐ and 20‐mM N) promoted mean final germination proportion of all eight species by 4.4% and 6.4%, but high concentrations (40 mM N) had no effect. The mean germination rate was decreased 2.1% and 5.1% by higher N concentration (20‐ and 40‐mM N) levels, but germination start time showed the opposite trend, delayed by 0.7, 0.9, and 1.8 d for the 10, 20, and 40 mM N treatments. Final germination proportion, mean germination rate, and germination start time were significantly different among species in response to N concentration treatments. The final germination proportion of Allium tenuissimum and Chenopodium glaucum were suppressed by increased N concentration, whereas it increased for Potentilla bifurca, Plantago asiatica, and Setaria viridis. Our findings provide novel insights into N deposition‐induced species loss based on seed germination factors in semi‐arid grassland communities.

Substrate Type and Temperature on Germination Parameters of Butterfly Pea

Butterfly pea (Clitoria ternatea) is a unique perennial and leguminous plant that produces brightly colored flowers that can be used as a pH-dependent natural food colorant in culinary and cosmetic preparations. Butterfly pea is commonly propagated from seed. Because of the increased interest in its commercial applications, effective production techniques are necessary to ensure consistent and successful commercial production. The objective of this research was to determine the influence of the substrate type and temperature on butterfly pea germination. Two substrate types (rockwool and commercial soilless substrate mix) and three temperatures (70, 80, and 90 °F) were evaluated to determine their effects on germination of butterfly pea seed. Collected and calculated germination data included germination capacity (G), mean germination time (MT), coefficient of variation of the germination time (cvt), mean germination rate (MR), uncertainty of the germination process (U), and synchrony of the germination process (Z). Differences were observed among substrate temperatures for the MT, cvt, and MR values, with germination greater at both 70 and 80 °F than at 90 °F. Similarly, significant differences among substrate types were observed for the G, MT, cvt, and MR values, with germination of seeds in rockwool outperforming seeds in soilless substrate mix. Because of the high priority for successful and uniform germination in commercial plant production operations, the results suggest that commercial germination of butterfly pea would be best in rockwool at 70 °F. Results of this study can be used for the commercial production of butterfly pea, for which propagation from seed is the primary means of plant production.

The Influence of temperature and Microwave Radiation on The Lesser Grain Borer Rhyzopertha dominica (F.) (Coleoptera : Bostrychida).

The effect of high and low temperature and microwave radiation on the adult of the lesser grain borer, Rhyzopertha dominica (F.) infested wheat seeds was studied. At high temperature (55°C), 29% of the death occurred after 30 minutes and the complete death occurred after 60 minutes. The lethal time of 50% mortality (LT50) and lethal time of 90% mortality (LT90) values were 36.96 and 63.4 minutes. Cold temperature (-7°C) caused 12% mortality after 20 minutes and complete succumb was obtained after 75 minutes. The LT50 and LT90 values were 38.6 and 71.3 minutes. Microwave at power of 2450 MHZ caused 33% mortality after 10 seconds and 100% mortality after 35 seconds. The LT50 and LT90 values on this power were 12.8 and 26.3 seconds. The mean germination rate of wheat seeds was 5% for microwave treatment (2450 MHZ, 30 seconds). However, 70% germination rate was achieved when the seeds were exposed to low temperature (-7°C, 3 months), and 77.5% when high temperature (55°C, 60 minutes) were used. In conclusion, the present study showed that, cold temperature (-7°c), high temperature (55°c), and microwave radiation had been successfully controlled R. dominica in a short period of time, however, microwave radiation had adverse effects on the germination of wheat seeds. Radiation seeds should therefore not be used in planting.

Comparative study of various pretreatment on seed germination of Dalbergia cochinchinensis

Dalbergia cochinchinensis belongs to family Fabaceae, is a hardwood tree species listed as vulnerable on the IUCN Red List of Threatened Species. This species is a slow-growing and it is threatened by overexploitation for its timber and illegal logging. Because of the increased demand for the timber, the species is rapidly disappearing in many habitats and threatened to extinction in the near future. Prevention of illegal logging and conservation efforts are required to protect the species. Seed germination and seedling growth is a critical step for the abiding conservation of plant germplasm. An experiment was to find out appropriate pre-sowing treatment for maximizing the germination. Eighteen pre-sowing treatments were used for both the seeds sown on moist filter paper and soil. Data was collected daily for calculated germination percentage, mean germination time, mean germination rate and growth performance. Results revealed that hot water treatment was effective to increase the germination rate comparison to the control and other treatments such as cold treatment and scarification. Significantly higher germination percentage (34.4%) and mean germination rate (0.17) were recorded in seeds were soaked in hot water 70 °C for 1 min (T1). Beside, seedling growth such as number of leaves, leaf length and seedling height originated from hot water treatment performed significantly higher than others. The results indicated that seeds treated with hot water had profound and significant impact on seed germination and growth of D. cochinchinensis.

Development of an Embryo Rescue Protocol for Butterfly Weed

We documented a successful embryo rescue (ER) protocol for butterfly weed (Asclepias tuberosa), a member of the milkweed family (Asclepiadaceae). Milkweed (Asclepias sp.) includes more than 100 species native to the United States, is an important pollinator plant, and has many commercially desirable traits. However, there is little commercial production outside of native plant nurseries because milkweed species are typically seed-grown and suffer from low seed set during pollination, late-term abortion of seed pods, and nonuniform germination. This project determined the optimal growing media (study one) and embryo maturity (study two) to recover mature seedlings from excised embryos and compared the results to those of traditional methods of seed germination (in soilless substrate). Study one investigated three different media: Murashige and Skoog (MS) medium at full strength and half strength and woody plant medium. MS medium at half strength was optimal for butterfly weed germination and maturation, with greater root and shoot lengths at the time of harvest. In study two, the effects of MS medium at half strength on embryo maturation 90, 60, and 30 days after pollination (DAP) were investigated. The optimal time to harvest embryos was 60 DAP; embryos at 30 DAP were capable of germination but not maturation. A mean germination rate of 97.4% was observed when using embryo rescue, but it was 72.3% with mature seed germinated in soilless substrate typical of commercial production. A similar increase in germination rates was observed for all embryo maturities when compared with seed germinated using soilless substrate. The protocol developed for this study should help to standardize production, reduce propagation time, and improve the commercial acceptance and profitability of milkweed.

Passage Through a Bird’s Gut Confers a Germination Head Start to the Seeds of the Nightshade Witheringia stramoniifolia

In frugivory networks, birds offer plants the advantage of dispersing their seeds away from the parent plants in exchange for macronutrients, primarily sugars, and water. The benefits for birds are clear, as they obtain food and water from fruits, and highly variable for plants, as birds may act in ways that vary from effective dispersers to seed predators. We studied two common species that interact frequently in the frugivory network of a Neotropical, periurban park: The clay-colored thrush ( Turdus grayi) and a nightshade ( Witheringia stramoniifolia), in order to evaluate the advantage of passing its seeds through a bird’s gut. We set up an investigation using captive thrushes that we fed with fruits of W. stramoniifolia. We had four experimental treatments: in two of them, seeds that had passed through the digestive tract of thrushes were germinated under greenhouse and controlled conditions; in the remaining two treatments, we germinated seeds that were not consumed by thrushes and were likewise germinated under greenhouse and controlled conditions. W. stramoniifolia seeds consumed by birds had a germination onset that was 1 to 2 weeks earlier than nonconsumed seeds. Mean germination rate and final germinability, however, did not differ significantly among treatments. In our study, passage through a bird’s gut accelerates the germination onset of seeds, an advantage that possibly enhances seedling establishment, but is not indispensable, for the dispersal of W. stramoniifolia. This bird–plant relationship ultimately accounts to a true mutualism.

Impact of synthesized metal oxide nanomaterials on seedlings production of three Solanaceae crops

Prospective involvement of metal oxide nanomaterials as a prominent agriculture practice for improving existing crop production directed the present investigation for synthesizing of ZnO and TiO2 nanomaterials as an attempt to enhance the transplants production of some Solanaceae crops. The morphological characterizations of the prepared nanomaterials indicated that the hydrothermal synthesized ZnO was produced in nanorod structure with an average aspect ratio of 7. However, SEM and TEM micrographs of microwave prepared TiO2 evident that it has a nanoparticle structure with an average diameter of 43 nm. The BET results confirmed the high specific areas of the two prepared metal oxide nanomaterials. The two synthesized metal oxide nanomaterials were coated in gel and mixed with the seeds of eggplant, pepper and tomato crops at four concentrations 0, 50, 100 and 150 mg/L, whilst the control seeds were germinated in distilled water without gel-coating. The results pointed to the outstanding effect of TiO2 and ZnO nanoparticles on germination characters and seedlings growth. The maximum transplants lengths, fresh and dry weight were recorded at the level 100 mg/L whatever the crop plant used. Hastening germination operation of nanomaterials-gel coated seedlings compared to control plants may be ascribed to the reduction of mean germination time and coefficient variation of the germination process besides increasing the mean germination rate and the synchrony of germination traits. Overall, better performance of growing transplants has been accredited for nanoparticles-gel coated seedlings more than the control treatments which could be efficient for the safer production of transplants in an innovative way.

GERMINATION RATE OF PENNISETUM GLAUCUM SEEDLING IN FUCTION OF SALINE STRESS, GROWTH AND BIOMASS OF AERIAL PART AND ROOT

Millet is an annual cycle plant, with C4 metabolism, tolerant to water deficit, and it is cultivated in regions with scarcity of rain. The objective was to evaluate the germination of the millet seedling in function of saline stress, growth and biomass of the aerial part and the root system. The experiment was performed in a completely randomized design, with four treatments and five replicates, with the unit being represented by seeds of millet. The treatments were constituted by solutions with addition of NaCl corresponding to 2.337, 4.674 and 7.011 g/L, respectively for the electrical conductivities 4.0; 8.0; 12.0 dS/m and 0 dS/m (distilled water) as control. The millet cultivar used in this experiment was the IPA Bulk 1BF. The mean germination rate of seedlings in relation to control salinity level was higher than 90%, while for level of 12 dS.m-1 salinity there was no germination. The fitted model presented a high coefficient of determination (pseudo-R²= 90.96%) and low sum of squares of residuals (SSR=0.26). The beta regression model proved to be an appropriate option to analyse the millet seedling germination rate after 72 hours in function of salinity level, length of the root system and dry mass of the aerial part.