Seedling Vigor Research Articles

Agronomic adaptations to heat stress: Sowing summer crops earlier

CONTEXTSummer crops are exposed to heat and drought stresses at critical stages during and after flowering, and their intensity and frequency are likely to increase with climate change. Agronomic stress avoidance offers the opportunity to temporally separate critical crop stages from heat and drought events. However, it might require sowing cold-sensitive summer crops earlier into colder than recommended soil temperatures. There is a need to understand how cold is too cold to sow summer crops early in late winter as well as what are the yield benefits and risks. OBJECTIVEHere, we quantify the likely benefits and trade-offs of sowing sorghum, a summer cereal, earlier to adapt to the increased frequency and intensity of heat and water stresses during flowering and grain filling. METHODSTwo years of multi-environment (n=32) genotype by management trials were conducted across the main sorghum growing regions of Australia. Environments (E) consisted of the combination of years, sites, three times of sowing (early, spring, and summer), and the use of supplementary irrigation. At each E a factorial combination of four plant populations (M) and eight commercial sorghum hybrids (G) were sown with three replications. Crop growth and yield components were measured, and the APSIM model was used to simulate all trials and treatments to quantify risks and derive insights into functional relationships between simulated and measured environmental covariates, and measured crop traits. RESULTSThe tested hybrids showed small differences in cold tolerance during crop establishment. Across the tested environments, the G×M combinations produced up to 60% variation in treatment yields across environment yields, which varied between <0.5 to about 10t ha-1; this translated into a ~5.5-fold variation in water use efficiency. Significant G×E and M×E interactions were observed for grain yield components. No G×M or G×E×M interactions were observed on yield or yield components. Early sowing was associated with a reduced risk of heat stress and water use transfer from vegetative to reproductive stages. Early sowing in late winter or early spring resulted in no significant yield gain or loss when all sites and years were included in the analysis. However, early sowing yielded between 1-2 t ha-1 more when the hottest sites and years were considered separately. This resulted from both the avoidance of heat stresses and milder or no terminal drought stresses. CONCLUSIONSEarly sowing of sorghum can reduce the likelihood of heat stresses around flowering as well as the likelihood of terminal drought stresses. Advantages include reduced yield losses in the hottest years and a transfer of water use to grain filling stages, resulting in increased grain yield and improved grain quality parameters. IMPLICATIONSEarly sowing, an agronomic adaptation, offers the opportunity to quickly adapt to the increase in the frequency and intensity of extreme hot events during critical crop stages. However, for the practice to be de-risked, there is a need to increase cold and chilling tolerance in sorghum and/or identify interventions that enhance seed germination and seedling vigour when the crop is sown early into cold soils.

Impacts of black soldier fly, Hermetia illucens, larval frass on the emergence and seedling vigor of three vegetable crop species

Abstract The waste material from rearing black soldier fly, Hermetia illucens (L.), (Diptera: Stratiomyidae), larvae (BSFL), frass, could serve as a partial replacement for fertilizer or growing media, such as peat. Studies have shown that depending on the crop life cycle, long or short, the incorporation of frass can have positive impacts on vegetable growth. Investigating the earlier stages of growth, such as emergence, can provide more information on the acute impacts of insect frass on plant production. Two greenhouse studies were designed to investigate the use of frass in vegetable production at the seedling stage: BSFL frass as a partial replacement for peat in a growth germination medium and BSFL frass as a fertility replacement in a growth germination medium. Tomato, lettuce, and arugula seeds were grown in a standard control growing media, a growing media amended with frass to partially replace peat, and a growing media with frass applications to substitute the fertility source. In all treatments and varieties, the control growing media produced better or comparable results to the treatments. As a peat replacement, the two tomato varieties, lettuce, and arugula seedlings grown in frass had comparable seedling vigour and days to emergence to those grown in the control. As a fertility replacement, seedlings grown in frass had significantly lower percent emergence in all four cultivars when compared to the control. The tomato varieties also had significantly lower seedling vigour in the BSFL fertility treatments than the control. Depending on crop and growing media composition, the impacts of frass on early plant development vary. The adoption of frass into growing practices should include preliminary tests for nutrient composition and microbial contamination.

Evaluation of Field Performance of Groundnut Varieties through Different Vigour Tests

A field experiment was carried out to evaluate the field performance of groundnut varieties through different vigour tests during Rabi, 2023-24 at S.V. Agricultural College, Tirupati, Acharya N.G. Ranga Agricultural University, Andhra Pradesh. The experimental material consisted of 10 groundnut varieties Narayani, Dharani, Dheeraj, TCGS-1694, Nithya Haritha, Kadiri-9, Kadiri-6, Kadiri Amaravathi, Kadiri-1812 and TAG-24 collected from different sources. In the preliminary experiment seed multiplication was done and the multiplied seed was used for conducting six vigour tests namely Germination test, speed of germination test, Seedling vigour index-Ⅰ, Seedling vigour index-Ⅱ, Accelerated ageing test, Electrical conductivity test in the laboratory using Completely Randomised Design with four replications. The multiplied seed was used for evaluating field performance using Randomised block design with three replications. Significant differences were found among the varieties based on vigour levels. Results with respect to field experiment showed that growth parameters i.e. field emergence percentage, days to 50 % flowering, days to maturity, number of branches per plant, number of pods per plant, pod yield per plant, kernel yield per plant, pod yield per plot, plant height, shelling percentage, 100 seed weight and harvest index varied significantly among different varieties based on different vigour levels. Varieties with higher vigour had shown higher field emergence percentage. Among the ten varieties Kadiri-6 had shown highest field emergence percentage. Significant correlation was observed among laboratory and field experiments. Vigorous varieties were able to perform better in terms of some of the field parameters and among all the vigour tests performed speed of germination test had high correlation with field emergence.

Effect of Green Synthesized Silver and Zinc Nanoparticles on Seed Quality OF Maize

Nanotechnology is an emerging science and has wide applications in agriculture. Green synthesized nanoparticles are safer, cost effective and eco-friendly over chemical and physical synthesis. The laboratory experiment was conducted to investigate the effectiveness of green-synthesized silver and zinc nanoparticles on seed quality of maize hybrid (GH-150125) during 2023-24 at the Department of Seed Science and Technology, University of Agricultural Sciences, Dharwad. Green synthesis of silver and zinc nanoparticles were mediated through neem (Azadirachta indica) leaf extract is as reducing and capping agent. The standardization for effective concentration and priming duration for silver and zinc nanoparticles were standardized from different concentrations of (250 ppm, 500 ppm, 750 ppm and 1000 ppm). For priming effective duration were standardized from six, eight and twelve hours inclusive of hydropriming and control (untreated). The effective concentrations of 250-750 ppm and duration of 8 h and 6 h from AgNPs and ZnNPs recorded higher respectively as compared to control and hydropriming. In laboratory, the seed treated with zinc nanoparticles at 750 ppm for 6 h recorded significantly higher germination percentage of (97 %), shoot length (21.53 cm), root length (20.17cm) and seedling vigour index I (4045) compared to control. Hence, the results conclude that ZnNPs at 750 ppm for 6 hours was superior as seed treatment in maize to enhance seed germination and seedling growth than other treatments.

Identification of Candidate Genes for Soybean Storability via GWAS and WGCNA Approaches

Soybean (Glycine max (L.) Merr.) is an important crop for both food and feed, playing a significant role in agricultural production and the human diet. During long-term storage, soybean seeds often exhibit reduced quality, decreased germination, and lower seedling vigor, ultimately leading to significant yield reductions in soybean crops. Seed storage tolerance is a complex quantitative trait controlled by multiple genes and is also influenced by environmental factors during seed formation, harvest, and storage. This study aimed to evaluate soybean germplasms for their storage tolerance, identify quantitative trait nucleotides (QTNs) associated with seed storage tolerance traits, and screen for candidate genes. The storage tolerance of 168 soybean germplasms was evaluated, and 23,156 high-quality single nucleotide polymorphism (SNP) markers were screened and analyzed through a genome-wide association study (GWAS). Ultimately, 14 QTNs were identified as being associated with seed storage tolerance and were distributed across the eight chromosomes of soybean, with five QTNs (rs25887810, rs27941858, rs33981296, rs44713950, and rs18610980) being newly reported loci in this study. In the linkage disequilibrium regions of these SNPs, 256 genes were identified. By combining GWAS and weighted gene co-expression network analysis (WGCNA), eight hub genes (Glyma.03G058300, Glyma.04G1921100, Glyma.04G192600, Glyma.04G192900, Glyma.07G002000, Glyma.08G329400, Glyma.16G074600, Glyma.16G091400) were jointly identified. Through the analysis of expression patterns, two candidate genes (Glyma.03G058300, Glyma.16G074600) potentially involved in seed storage tolerance were ultimately identified. Additionally, haplotype analysis revealed that natural variations in Glyma.03G058300 could affect seed storage tolerance. The findings of this research provide a theoretical foundation for understanding the regulatory mechanism underlying soybean storage.

Improving the Germination Performance of Kalmegh (Andrographis paniculata Wall. ex Nees) through Hydropriming, Halo-Priming and Osmopriming Under Salinity Condition

Salinity is a significant global issue that adversely affects seed germination and seedling vigour across a wide range of crops. Priming, however, is considered a basic method to enhance seed performance (germination and vigour) under saline conditions. The aim of this study is to evaluate the effects of different priming treatments on seedlings under varying salinity levels (0, 4, 6, 8, and 10 dS m⁻¹) in Kalmegh, a traditionally valuable medicinal plant. Seeds were primed through four methods viz., T0- Non-primed (control), T1- Hydro primed (distilled water), T2- halo priming with NaCl (0.8%), T3- halo priming with CaCl2 (0.8%) and T4- osmo priming with KNO3 (1%) for 6 hours at 25ºC in the dark. This experiment was arranged in a factorial design based on a CRD (Completely Randomized Design) with three replications. The results demonstrated that priming treatments significantly improved germination percentage, seedling length (cm), seedling fresh weight (mg), seedling dry weight (mg), and vigour indices. Notably, seeds primed with KNO3 showed the highest germination performance at all salinity levels. Even at the highest salinity level, they achieved a germination percentage of 94% and a Seedling Vigour Index I of 506, compared to the control group, which exhibited a germination percentage of 88% and a Seedling Vigour Index I of 298. KNO3 priming at 0 dS/m produced the highest seedling length (8.5 cm), root length (2.7 cm), shoot length (6.4 cm), fresh weight (26.32 mg), and dry weight (10.3 mg).

Seed size and &lt;i&gt;Azospirillum brasilense&lt;/i&gt; Ab-V5 and Ab-V6 inoculation influences germination and early seedling vigor of &lt;i&gt;Acacia mearnsii&lt;/i&gt;

Acacia mearnsii is an Australian native tree species commercially grown in Africa and South America that produces tannins and woodchips. Its seed size varies, which may impact the germination and initial growth of seedlings. In its turn, Azospirillum brasilense inoculation is known to improve the growth of several crops. However, there are few studies the effects of A. brasilense inoculation on the germination and initial growth of forestry species. The present study evaluated the influence of seed size and A. brasilense Ab-V5 and Ab-V6 inoculation on germination and initial growth of A. mearnsii. Small seeds reduced the mean germination time (MGT) by 5.2% and the time to 50% germination (T50) by 23.8% in comparison to large seeds. On the other hand, seedlings that originated from large seeds had a seedling vigor index (SVI) 18.6% higher than those that originated from small seeds. Azospirillum brasilense inoculation increased the germination percentage by 20.9%, germination speed by 91.8%, root length (RL) by 35.8%, and root fresh weight by 20.5%. Additionally, it decreased MGT by 8.2% and T50 by 37.6%. The combination of large seeds and A. brasilense inoculation increased RL by approximately 50% and SVI by 62.1%. Thus, the use of A. brasilense inoculation favors germination and seedling vigor in A. mearnsii, showing to be a promising strategy for obtaining more uniform seedlings in forest nurseries.

Determination of Seed Physiological Maturity and Invigoration using Plasma-Activated Water and Ultrafine Bubble Water on Okra Seeds

Seeds physical and physiological qualities are primarily determined by seed physiological maturity. Seed enhancement technology has developed rapidly, including using ultrafine bubbles (UFB) and plasma-activated water (PAW) to increase seed viability. This study aimed to determine seed physiology maturity on okra seed to get the optimal harvesting period seeds and to examine the most effective seed enhancement plasma-activated water and ultrafine-bubble Water. The first experiment was arranged using completely randomized design with fruit maturity as the single factor, harvested at 3, 4, 5, or 6 weeks after anthesis (WAA), with three replications. The second experiment used factorial completely randomized design; the first factor is seed lots with different storage times (fresh seed and one-year storage seed), and the second factor seed invigoration using UFB (20 ppm dissolved oxygen) and PAW (10-, 20-, and 30-min exposure) as the second factor. Untreated seeds were used as control. Fifty seeds were used in each treatment. Okra seed physiological maturity was reached at 5 WAA based on seed dry weight, germination capacity, seedling vigor, and speed of germination. The pod color at 5 WAA is olive brown, and seed testa has dark greyish purple. Plasma-activated water at 10 minutes exposure increased the vigor index of seed lots stored for one year by 86% and PAW20 by 87%. Plasma activated water at 10-, 20- and 30-minutes exposures significantly increased the seedling vigor index and germination speed of fresh seeds harvested at 5 WAA.

Growing Vigorous Potato Seedlings in Plug Trays

AbstractRaising vigorous and healthy potato seedlings from hybrid true potato seeds (TPS) under nursery conditions is critical for ease of field transplanting and seedling crop establishment as well as for a productive seed or ware crop. The use of plugs in seedling production systems is an important technique utilised to ease transplanting of seedlings and refine seedling production in seedling nurseries. While holding multiple advantages over other transplant production systems, multiple factors still influence the success of seedling production in plug trays. In this study, we explore the effects of substrate properties, type and volume; watering intervals; and nitrogen (N) and phosphorus (P) levels in nutrient solution on seedling vigour attributes in potato seedlings grown in plug trays under climate room conditions. The choice of substrate strongly influenced seedling attributes with more favourable performance in substrates with higher water holding capacity. Increasing plug volume also enhanced seedling attributes including dry biomass, leaf area and root to shoot ratios such that seedling performance was best in plug volumes &gt; 22.5 cm3. A watering schedule with a high frequency was more favourable considering that longer intervals between watering events led to significant declines in seedling attributes. While the effects of increased P in solution were not conclusive, depending on genotype, increasing N in solution led to enhanced seedling attributes, with a nutrient sufficiency met at 200 mg L−1 N in solution. These findings further contribute to the current knowledge on factors influencing success in seedling production of potato seedlings developed from hybrid true potato seeds.

Effects of dynamised high dilutions and vegetal extract based on silicon on the growth and induction of resistance in tomato plants against Rhizoctonia solani

ABSTRACT The objective of this study was to study the response of tomato (Solanum lycopersicum) against Rhizoctonia solani using dynamised high dilutions and plant extract based on silicon. The treatments were Silicea terra (ST), Thuya occidentalis (TO), and Equisetum arvense (EA) at 30CH (Centesimal Hahnemannian dilution order), Equisetum arvense leaf extract (LE), and non-dynamised water as the control. Seeds of tomato cv Marmande were treated overnight. The in vitro bioassays involved assessment of R. solani mycelial growth, seed germination, and seedling development. In the greenhouse experiment, the emergence, root and aerial part development, and disease development were evaluated. Leaves were harvested to analyse concentrations of flavonoids, phenolic compounds, chlorophyll, carotenoids, and chitinase activity. In the in vitro bioassay, LE reduced mycelial growth and TO increased the seedling vigour index, dry weight, and length of seedlings. In the greenhouse experiment, TO and ST increased plant emergence. Tomato plants treated with ST improved the fresh weight and the length of the roots. The disease severity was decreased by ST, LE, and TO. The flavonoid concentration was higher in plants treated with TO and LE. Overall, the treatments of TO, EA, and ST improved the content of phenolic compounds. Moreover, endochitinase and chitobiosidase were activated by LE.

Influence of Green Synthesized Silver and Zinc Nanoparticle on Seed Quality Attributes in Red Sander (Pterocarpus santalinus Linn.)

Red Sanders (Pterocarpus santalinus), or Rakta chandana, is an endangered tree native to the Southern Indian Peninsula, valued for its medicinal and dye properties. However, its germination is hindered by a hard seed coat, phenolic compounds and hormonal imbalances. Nanotechnology in forestry enhances product innovation, paper processes and sustainability through plant-based nanoparticle biosynthesis. The experiment used a completely randomized design (CRD) with three replications and evaluated seven presowing treatments: T1 (AgNPs at 1000 ppm for 24 hours), T2 (ZnNPs at 2000 ppm for 24 hours), T3 (Conc. H2SO4 for 12 minutes), T4 (NaDC 500 ppm), T5 (Dewinging), T6 (soaking in hot water at 100°C for 5 minutes) and T7 (control). The results indicated that seeds treated with ZnNPs at 2000 ppm (T2) exhibited highest germination rate (56%), germination speed (1.04), root length (17.05 cm), shoot length (16.33cm) and highest dry weight (6.22 g) and highest seedling vigour Index-I (1869). In comparison H2SO4 treatment (T3) delivered 51.67 per cent germination and a speed of germination (0.95), with root length (15.28 cm), shoot length (16.22 cm), dry weight (5.24 g) and seedling vigour Index (1628) slightly lower but still significant. The control (T7) had the lowest performance with 31 per cent germination, a speed of 0.36, root length (15.28 cm), shoot length (16.22 cm), lower dry weight (1.63 g) and the lowest Seedling Vigour Index (649). Overall, ZnNPs at 2000 ppm (T2) were the most effective in enhancing germination, seedling growth and overall vigour in Red sanders.

Proline Priming Enhances Seed Vigour and Biochemical Attributes of Rice (Oryza sativa L.) during Germination.

Seed vigour is a desirable trait especially for direct seeded rice (DSR) cultivation. Seeds with high vigour could improve seed germination, support seedlings in competing with weeds for water and nutrients, and improving seedling establishment throughout the early stages of crop growth. The success of DSR system which account for more 25% of world cultivation areas is highly dependent on the seed vigour and seedling establishment. Seed priming is a promising technique to improve seed vigour. Proline is an amino acid that has been well studied for its roles in plants under different environmental stress conditions. Nevertheless, the effect of proline as a seed priming agent in improving seed vigour in rice remain elusive. In this research, the effect of 24 h of proline priming at various concentrations (0 mM, 1 mM, 2 mM, 10 mM and 20 mM) on rice seed vigour, amylase activity, and total soluble sugar (TSS) content of a Malaysia indica rice variety, MR269 was investigated. Results showed that seeds primed with lower concentration of proline (0 mM, 1 mM and 2 mM) had better germination responses while priming at high concentrations (10 mM and 20 mM) reduced seed germination. Among the concentration tested, priming with 1 mM proline enhanced seed vigour with significantly higher germination percentage (GP), germination rate index (GRI) and seedling vigour index (SVI). In addition, proline primed seeds also exhibited increased amylase activity and TSS content as compared to unprimed seeds. However, priming seed with 20 mM proline was detrimental to the seed vigour and seedling growth whereby lower GP, GRI and SVI and higher mean germination time (MGT) were observed. In short, this study shows that proline could be a potential seed priming agent to improve seed vigour in rice.

Using Empirical Performance Data to Source Bluebunch and Snake River Wheatgrass Plant Materials to Restoration Sites in the Eastern Great Basin, USA.

To infer adaptation of plant material, restoration practitioners often consider only surrogate geographic or climatic information. However, empirical biomass data could assist in deciding what material to use where. To test this approach, we transplanted seven bluebunch wheatgrass (BBWG; Pseudoroegneria spicata) and five Snake River wheatgrass (SRWG; Elymus wawawaiensis) populations to three sites ranging from low to high precipitation (LPPT, MPPT, and HPPT). We measured establishment-year (2011) biomass at all sites and 2012-16 biomass at MPPT and HPPT. When data were standardized by site, P-7 and Anatone produced the mostBBWG biomass across sites and Wahluke the least in both 2011 and 2012-16, while E-58X produced the most SRWG biomass and Secar and E-49X the least in 2011 and 2012-16, respectively. Among BBWG populations in 2011, relative performance of P-7 (G6 generation) and Goldar increased and Whitmar decreased at wetter sites, while Columbia was stable (high) and Wahluke was stable (low) over sites. Among SRWG populations in 2011, Secar, Secar78, and E-58X increased at drier sites and Discovery at wetter sites. However, once established, populations of both species were much more similar for trend. In 2012-16, trend somewhat increased for five BBWG populations from MPPT to HPPT, was stable for Wahluke, but declined for Columbia, while all five SRWG populations declined at HPPT. These results suggest that, once established, BBWG is mostly stable across sites, while SRWG is less adapted to wetter sites. In 2012-16, BBWG populations originating at drier (or wetter) sites mostly performed relatively better at MPPT (or HPPT), suggesting adaptation to site. However, in the establishment year (2011), this relationship did not hold, suggesting seedling vigor and immature growth rate play a stronger role than precipitation at the site of origin.

Variation in Seedling Quality Attributes of Lentil (Lens &amp;lt;i&amp;gt;culinaris&amp;lt;/i&amp;gt; Medik.) After Harvested Under Different Sowing Dates

Planting dates are the most important components for Lentil seedling growth and development. Seeds planted in diverse environmental situations lead to changes in various seedling development and the final output of the yield. The present study, aimed to assess the effect of different planting (sowing) dates harvested seeds on the physiological properties of nineteen (19) lentil genotypes. Lentil was growing during two consecutive planting days on average the normal (main) 17/08/2021 and lately 16/09/2021, then harvested seed extract after five months of storage, planted CRD with two factorial designs and three replications under laboratory condition within a white plastic container filled with autoclaved 3.0kg sand applying 100ml distilled water. The lentil was grown per standard, and the lentil&amp;apos;s postharvest physiological quality parameters were evaluated. Results indicated that the lowest speed of germination index was obtained during late planting time or stress situations on the genotype Adda (8.78) and ILL-1760 (8.94). Seedling length is the seedling vigor criterion and is statistically significantly different between planting dates at 1%. The effect of planting day on seedling fresh weight was significantly different (p &amp;lt; 0.01) on genotype Beredu (0.0022) on the main planting day. The seed viability on vigor index (II) as shown in was affected by planting date (p &amp;lt; 0.01) and genotypes (p &amp;lt; 0.01). The heritability value of shoot length, root length, and seedling fresh weight equal zero was the variation due to environmental it had no genetic effect after five months of storage both main and late planting. The seedling vigor index, fresh and dry weight traits maximum on the main planting day on the genotype Beredu indicates 0.0445, 0.00218, and 0.00045 respectively. Seeds from the main planting day had the best seedling traits performance and recorded minimal germination time compared to late planting seeds. Lentil seeds planted lately finally recorded lower seedling fresh and dry weight, vigor, and speed of germination index as compared to those harvested lentil seeds in main planting dates. As a result, when there is adequate rainfall necessary for lentil growth, development, and final output.

Biopriming using microbial consortia and biostimulants as a technique to increase seed quality of Solanum melongena L. by modifications in morphological and metabolic constituents

Brinjal (Solanum melongena L.) is a widely cultivated vegetable in tropical and subtropical regions. High-quality seeds are crucial for successful crop production, necessitating rapid and uniform field emergence. In the new wave of the Green Revolution, organic wastes were replaced by agrochemicals. This study was conducted from January to March 2024 to standardize biopriming techniques for brinjal using various organic inputs and microbial cultures to improve seed quality. Brinjal seeds cv. PLR 2 were treated with organic inputs (Panchagavya, Egg fermented extract, Fish fermented extract and effective microorganism solution) and liquid microbial cultures (Azospirillum and Pink Pigmented Facultative Methylotroph). The bioprimed seeds were assessed for their physiological attributes and anatomical and biochemical changes. Compared with the control, biopriming with 2% Fish fermented extract significantly improved the germination rate (19.4%), germination energy (40.9%), root length (44.4%), shoot length (24.4%) and seedling vigour index (68.1%). This increase was attributed to the nutritional and bioactive compounds in the fish by-products, which promoted root development and nutrient absorption. The biochemical parameters revealed increased ?-amylase activity, protein, and amino acid content in the bioprimed seeds. Gas Chromatography-Mass Spectrometry (GC-MS) analysis revealed beneficial root volatile compounds in the roots of treated seeds. An evaluation of the plant growth-promoting activities of the biopriming agents revealed the superiority of fish-fermented extract over other bioagents. Therefore, this method promotes sustainable agriculture and improved crop productivity, providing a scientific basis for biopriming as a viable alternative to conventional seed treatments.

ENHANCING GERMINATION AND SEEDLING VIGOR IN NIGELLA SATIVA: THE IMPACT OF NANO IRON OXIDE AND PHOSPHORUS PRIMING

Nigella sativa, commonly known as black cumin, is known for its health benefits due to its rich content of compounds like thymoquinone. This study explored the effects of various seed priming methods on Nigella sativa seeds, including control (unprimed), distilled water, nano iron oxide (Fe₂O₃), phosphorus (P), and a combination of Fe₂O₃ and P. We assessed how these treatments influenced several key aspects of seed germination: germination rate (GR), mean germination time (MGT), germination index (GI), coefficient of velocity of germination (CVG), and vigor index (VI).Our results showed that seeds treated with Fe₂O₃ nanoparticles had the highest germination rate at 93.5% and germinated faster than seeds from other treatments. This suggests that Fe₂O₃ nanoparticles effectively speed up the germination process. However, despite the improved germination rate, the seeds treated with Fe₂O₃ did not exhibit the highest seedling vigor; the control seeds had the highest vigor index, indicating that while Fe₂O₃ accelerates germination, it does not enhance seedling health as much as the untreated seeds. Additionally, there were no significant differences in the germination index and coefficient of velocity of germination between the treatments, suggesting these parameters were less influenced by the priming methods.In summary, nano-priming with Fe₂O₃ is effective for speeding up seed germination but does not necessarily improve seedling vigor. These findings provide valuable insights into how different priming techniques can be optimized to enhance seed performance and plant growth under various conditions.

Mitigation of salt stress in Sorghum bicolor L. by the halotolerant endophyte Pseudomonas stutzeri ISE12.

Increasing soil salinity, exacerbated by climate change, threatens seed germination and crop growth, causing significant agricultural losses. Using bioinoculants based on halotolerant plant growth-promoting endophytes (PGPEs) in modern agriculture is the most promising and sustainable method for supporting plant growth under salt-stress conditions. Our study evaluated the efficacy of Pseudomonas stutzeri ISE12, an endophyte derived from the extreme halophyte Salicornia europaea, in enhancing the salinity tolerance of sorghum (Sorghum bicolor L.). We hypothesized that P. stutzeri ISE12 would improve sorghum salt tolerance to salinity, with the extent of the increase in tolerance depending on the genotype's sensitivity to salt stress. Experiments were conducted for two sorghum genotypes differing in salinity tolerance (Pegah - salt tolerant, and Payam - salt sensitive), which were inoculated with a selected bacterium at different salinity concentrations (0, 100, 150, and 200 mM NaCl). For germination, we measured germination percentage and index, mean germination time, vigor, shoot and root length of seedlings, and fresh and dry weight. In pot experiments, we assessed the number of leaves, leaf area, specific leaf area, leaf weight ratio, relative root weight, plantlet shoot and root length, fresh and dry weight, proline and hydrogen peroxide concentrations, and peroxidase enzyme activity. Our study demonstrated that inoculation significantly enhanced germination and growth for both sorghum genotypes. The salinity-sensitive genotype (Payam) responded better to bacterial inoculation during germination and early seedling growth stages, showing approximately 1.4 to 1.8 times greater improvement than the salinity-tolerant genotype (Pegah). Payam also displayed better performance at the plantlet growth stage, between 1.1 and 2.6 times higher than Pegah. Furthermore, inoculation significantly reduced hydrogen peroxide, peroxidase activity, and proline levels in both sorghum genotypes. These reductions were notably more pronounced in Payam, with up to 1.5, 1.3, and 1.5 times greater reductions than in Pegah. These results highlight the efficacy of P. stutzeri ISE12 in alleviating oxidative stress and reducing energy expenditure on defense mechanisms in sorghum, particularly benefiting salt-sensitive genotypes. Our findings highlight the potential of the bacterial endophyte P. stutzeri ISE12 as a valuable bioinoculant to promote sorghum growth under saline conditions.

Effect of physical energy on germination and seedling vigor of alfalfa seeds (Medicago sativa L.)

Effect of physical energy on germination and seedling vigor of alfalfa seeds (Medicago sativa L.)

Effect of pre-sowing treatments on seed germination and postgerminative seedling growth of acacia angustissima (mill.)

Seeds of Acacia angustissima were subjected to a control and five pre-sowing (soaking in cold water for 24 hours, soaking in hot water (100° C) for 5 minutes, immersion in 60 % H2SO4 for 30 seconds, immersion in 60 % H2SO4 for 5 minutes, and immersion in 60 % H2SO4 for 15 minutes) treatments. The number of seeds that sprouted was recorded daily for calculation of germination indices. When there had been no further germination in any of the treatments for four weeks, the height, number of leaves, number of leaflets, and root length of seedlings were determined. One-way analysis of variance was used to test the effects of the pre-sowing treatments on seed germination and seedling growth. Final Germination Percentage, Germination Rate Index, and Seedling Vigour Index were significantly higher in the warm water than other five treatments which displayed similar responses of the traits. Similar, the warm water pre-treatment resulted in the longest seedlings, when shoot height and / or root length was considered. There was no significant effect of treatment on Mean Germination Time, number of leaves, and number of leaflets. The findings suggest that hot water pre-sowing treatment is the most suitable for seed germination and initial seedling height attainment of Acacia angustissima.

A point mutation in VIG1 boosts development and chilling tolerance in rice

The rice paddy-direct seeding system has been widely adopted due to its low cost and convenience, whereas its application is mainly constrained by low seedling vigor, cold sensitivity, eventually resulting in reduced grain yield. Here, we show vig1a and vig1b, two allelic mutants of OsbZIP01, that both demonstrate greatly enhanced seedling vigor and chilling tolerance but differ in final grain production. The vig1a phenotype can be obtained via simultaneous mutation of the genes OsbZIP01 and OsbZIP18, or by selectively manipulating the basic region of OsbZIP01. Destroying the leucine zipper region of OsbZIP01 in vig1a turns vig1a to be vig1b. Further analysis reveals that OsbZIP01 and OsbZIP18 function cooperatively in diverse crucial biological programs that determine seedling establishment, chilling tolerance, and grain yield through their interactions. These findings provide a strategy toward simultaneously improving seedling vigor, chilling tolerance, and grain yield for rice production.