Seed Germination Percentage Research Articles

Exploring the Phosphate Solubilizing Potential and Acid-Alkaline Phosphatase Activity of Two Multitrait Heavy Metal Tolerant Bacterial Strains Isolated from North Gujarat, India

A study was conducted to isolate and characterize phosphate solubilizing bacteria (PSB) from soils of various locations in North Gujarat. A total of 40 PSB isolates were obtained, exhibiting a phosphate solubilizing index (PSI) ranging from 2.11 to 4.33. Interestingly, among 40 PSB isolates, a subset of 16 displayed an additional trait of potassium solubilization, as evidenced by their potassium solubilizing index (KSI) values falling within the range of 2.10 to 3.10. These 16 PSB isolates were screened for tolerance to heavy metal stressors, namely CdCl2, HgCl2, Pb(NO3)2, and ZnSO4, spanning a concentration gradient from 0.1 mM to 10 mM. Remarkably, among the tested isolates, two, namely, D4 and G2, exhibited exceptional resilience against the heavy metal stressors, as indicated by their minimum inhibitory concentration (MIC). Specifically, isolate D4 showed MIC values of 5 mM, 0.2 mM, 18 mM, and 12 mM, respectively, against CdCl2, HgCl2, Pb(NO3)2, and ZnSO4. For isolate G2, the corresponding MIC values were 6 mM, 0.2 mM, 21 mM, and 11 mM. The bacterial isolates were molecularly identified as strains Klebsiella pneumoniae PHmD4 (abbreviated as D4) and Enterobacter chuandaensis PHmG2 (abbreviated as G2), based on sequence homology obtained from 16S rDNA gene sequencing and subsequent BLAST analysis. In Pikovskaya’s broth, K. pneumoniae PHmD4 and E. chuandaensis PHmG2 had phosphate solubilization values of 4.30 μ moles mL⁻¹ and 3.51 μmoles mL⁻¹, respectively, with terminal pH values of 3.06 and 4.07. Enzymatic activity assays conducted after 96 hours of incubation in Pikovskaya’s broth revealed that the highest acid phosphatase activity was 21.62 U mL⁻¹ for K. pneumoniae PHmD4 and 21.09 U mL⁻¹ for E. chuandaensis PHmG2. The highest alkaline phosphatase activity was 5.85 U mL⁻¹ and 6.38 U mL⁻¹, respectively. In the tomato seed germination study, both non-bacterized and bacterized tomato seeds achieved a 100% germination rate. However, increasing metal concentrations diminished the germination percentage of heavy metal-treated seeds. Interestingly, bacterization with K. pneumoniae PHmD4 and E. chuandaensis PHmG2 ameliorated germination under cadmium stress but had no mitigative effect under mercury and zinc stress conditions.

Biosolubilized zinc from ZnO in bacterial culture supernatant enhanced seed germination, early growth, and zinc accumulation in rice (Oryza sativa L.) under hydroponic system through seed priming method

Presently, zinc sulfate (ZnSO4) based fertilizers are reported inefficient in flooded paddy fields which necessitates to find a better alternative for sustainable rice cultivation. This study was conducted to find out the effectiveness of bacterially solubilized Zn (BSZn) on the early growth of rice plants and the concentration of Zn in the plant parts in comparison to conventional ZnSO4. BSZn preparations were obtained from culture supernatant following ZnO solubilization by bacterial isolates Burkholderia spp. and Achromobacter sp. The effectiveness of BSZn was assessed on rice seed germination on Petri plates and the growth of seedlings upon treatment in hydroponic culture under controlled conditions. In general, BSZn obtained from certain Burkholderia spp. increased seed germination percentage (SG%) (98–100%), mean germination rate (MGR), mean daily germination (MDG), decreased mean germination time (MGT) and impart stimulating effect on seed germination as indicated by increased vigor indices compared to ZnSO4 treatment regimes. The obtained data from the hydroponic culture of rice seedling growth indicated a positive influence of most of the BSZn preparation on dry and wet weight of roots and shoots, and seedling length compared to ZnSO4 at p < 0.05. Both chlorophyll and carotenoid content of the seedling increased in the presence of some BSZn preparations. In general, compared to shoot, the root of seedlings accumulated a higher amount of Zn (up to 888 µg Zn/g dry biomass). Zn concentration data indicated that BSZn16 obtained from Burkholderia sp. EIKU16 culture help to accumulate significantly higher amounts of Zn in rice seedlings under hydroponic culture than that while treated with ZnSO4.

Effect of Different Seed Treatment and Media on Shoot Growth of Ashwagandha, Withania somnifera (L.) Dunal

Indian Ginseng or Ashwagandha, is one of the most important Under the present study the seeds were soaked with treatment (S1) GA3 (250 ppm - 24 h.) recorded maximum germination percentage (66.11 %) and maximum plant height at 15 (3.00), 30 (8.38), 45 (15.98), 60 (25.20), 75 (34.05), 90 (42.98), 105 (52.07) and 120 (59.02) days, respectively. Maximum no. of branches/plant at 15 (0.0), 30 (0.22), 45 (0.71), 60 (1.73), 75 (1.76), 90 (2.80), 105 (3.0) and 120 (3.84) and no. of leaves/plant were also recorded higher in S1 at 15 (3.42), 30 (7.67), 45 (20.42), 60 (33.11), 75 (41.62), 90 (55.98), 105 (67.24) and 120 (75.87) DAS respectively. In the Similar treatment, no. of leaves were also found superior over other treatments with maximum total leaf area (33.57 cm2), shoot fresh weight (55.06 g), shoot dry biomass (38.34 g), plant fresh weight (60.10 g) and plant dry weight (18.77 g) as compared to other treatments applied.&#x0D; The treatment (M3) media combination of Red soil + Vermicompost + FYM (1:1:1) gave significantly highest results in context to seed germination percentage (71.94 %), total leaf area (32.08 cm2), shoot fresh weight (58.70 g), shoot dry biomass (40.91 g), plant fresh weight (64.05 g) and plant dry weight (19.82 g), respectively. In same treatment, highest plant height at 15 (3.29), 30 (9.78), 45 (18.14), 60 (26.85), 75 (35.54), 90 (44.13), 105 (55.03) and 120 (60.17), no. of branches/plant at 15 (0.0), 30 (0.27), 45 (0.68), 60 (1.89), 75 (1.97), 90 (2.87), 105 (2.90), 120 (3.83) and no. of leaves/plant at 15 (3.72), 30 (8.46), 45 (22.46), 60 (35.23), 75 (43.91), 90 (55.87), 105 (67.47) and 120 (75.92) respectively were recorded.&#x0D; Interaction effect between pre-sowing treatment and different media was observed significant in seed germination percentage and maximum (80 %) in the treatment S1M3.

Plant Growth Hormones and Micro-Tuberization in Breaking the Seed Dormancy of Bunium persicum (Boiss.) Fedts.

Bunium persicum is a valuable medicinal plant with limited production but high market demand. It thrives predominantly in high-altitude regions. The main challenges hindering its widespread cultivation are seed dormancy and a lengthy seed-to-seed cycle, making its large-scale cultivation difficult. Six genotypes of Bunium persicum were collected from different altitudes to evaluate its germination behavior and seed dormancy. The study was conducted during 2020-23 and comprised three experiments (viz., seed germination under an open field, controlled conditions, and micro-tuberization). Under open field conditions, germination percent was genotype dependent, and the highest germination percentage, root length, and shoot length were recorded in Shalimar Kalazeera-1. Germination behavior assessment of the Bunium persicum revealed that treatment T9 (GA3 (25 ppm) + TDZ (9 µM/L)) is effective in breaking the dormancy of Bunium persicum as well as in obtaining a higher germination percent for early development of the tubers. Similarly, with regard to the effect of temperature and moisture conditions, stratification under moist chilling conditions showed effectiveness in breaking seed dormancy as the germination percentage in stratified seeds was at par with the most efficient growth hormone. With regard to the in vitro micro-propagation, direct regeneration showed multiple shoot primordia at the base of the tubers without intervening callus phase from the MS medium supplemented with BA (22.2 µM) and NAA (13.95 µM) 4 weeks after sub-culturing. Similarly, medium supplemented with JA (8.0 mg/L) and BA (22.2 µM) produced well-organized somatic embryos with shiny surfaces, which appeared at the swelled basal portion of apical stems. Further, the combination of JA (6.0 mg/L) and BA (22.2 M) was effective in developing the micro-tubers and also enhanced the weight and length of Bunium persicum micro-tubers.

Reviving the Resilient: Exploring Pre-Dormancy Breaking Treatments for Acacia nilotica (L.)

Acacia nilotica plays an important ecological role in its native habitats and has great relevance for restoration as well as in terms of economic worth. Acacia nilotica species frequently exhibit seed dormancy, which makes planting and seed testing difficult. In the present work, we examined the degree of dormancy and the impact of various pre-treatments on the dormancy breaking of Acacia species. Several tests were carried out against this backdrop to standardize the mechanical scarification, seed priming, and coating techniques. The results showed that mechanical scarification of Acacia nilotica seeds with @6 min scarification improved the seed germination percentage and vigour index percentage by 117 and 184 percent over the control. Correspondingly, the application of the TNAU seed coating formulation on Acacia nilotica seeds at 2g kg-1 increased the germination percentage and vigour index percentage by 129 and 186 percent, respectively, over the control. Also, humid priming of Acacia seeds (12 h soaking in water + 2 days humid incubation) resulted in a gradual increase in the seed germination percentage and vigour index percentage by 181 and 263 percent over the control. The seeds were not harmed by any of these treatments, which all reduced hard seeds to zero and improved germination percentages.

Acid Rain and Seed Germination: A Predictive Model Using ML-based CART Algorithm

The impact of acid rain on the germination of seeds is a significant concern in agricultural and environmental studies. Acid rain, characterized by elevated acidity levels due to pollutants like sulfur dioxide and nitrogen oxides, can adversely affect the germination process of various plant species. The objective of this study was to evaluate the impact of simulated acid rain (SAR) on the germination of Brinjal (Solanum melongena Linn.) and Cowpea (Vigna unguiculata ssp. cylindrica L. Walpers) crops. The experiments were conducted using eight plastic trays of approximately 25 cm. x 30 cm dimensions. Four trays were used for experiments with brinjal seeds (Set I), while the other four were used for cowpea seeds (Set II). One tray from each set was used as positive control and treated with normal pH 5.6, while the other three trays from each batch were treated with SAR solutions of pH 4.5, 3.5, and 2.5. Brinjal seed germination percentage and seed vigor were inferior to Cowpea seeds. The seeds treated with SAR (pH 4.5, 3.5, and 2.5) showed hindered seed germination. Furthermore, a more significant inhibitory effect was observed at lower pH values. The mean germination percentage of seeds was highest for standard SAR (pH 5.6) in the case of Brinjal seeds, while it was recorded lowest for Cowpea seeds. The results indicate that plants do not respond uniformly to SAR. To investigate the behavior of the simulated acid rain data, a Machine Learning-based Decision Tree Algorithm was employed to identify and optimize conditions. Cowpea was predicted to get 95% seed germination, whereas brinjal would only be 64% in acid rain of pH value 5.05 for 36 hours. In conclusion, utilizing a Machine Learning-based CART algorithm has provided valuable insights into predicting the germination behavior of seeds under the influence of acid rain.

Development and characterization of intraspecific hybrids of low chill peach [Prunus persica (L.) Batsch

An experiment was conducted to broaden the range of early-ripening peach cultivars through hybridization. Low chill peach cultivars, specifically Shan-i-Punjab and Tropic Sweet, were selected as female parents and crossed with Florda Prince, Flordaglo, and Prabhat. Among the crosses, the highest fruit set (72.63%) was observed in Shan-i-Punjab x Florda Prince, while the lowest fruit set was recorded in Tropic Sweet × Flordaglo (18.87%). Despite the lower fruit set in Tropic Sweet crosses, they exhibited a significantly higher fruit retention percentage and a lower fruit drop rate than those involving the Shan-i-Punjab cultivar. Following ripening, seeds were extracted from the fruits and subjected to stratification at low temperatures until radicle emergence occurred. The stratification duration for the hybrid seedlings ranged from 76.00 days in Shan-i-Punjab × Florda Prince to 88.33 days in Tropic Sweet × Flordaglo. After sowing the seeds in the field, the highest seed germination percentage of 90.43 was recorded in Tropic Sweet × Florda Prince, which did not show a significant difference from Tropic Sweet × Flordaglo (88.94%), followed by Tropic Sweet × Prabhat (85.11%). Regarding seedling growth, Tropic Sweet × Flordaglo exhibited the maximum seedling height of 36.03 cm, while minimal variations were observed among different crosses regarding petiole length, leaf area, and internodal length.

Seed germination and storage conditions of Ilex embelioides Hook.f. (Magnoliopsida: Aquifoliales: Aquifoliaceae), a threatened northeastern Indian species

Ilex embelioides Hook.f. is a threatened tree species endemic to northeastern India. The species propagates naturally through seeds but shows a brief dormancy period. The present study was carried out to assess the germination behaviour, and identify the suitable storage conditions of I. embelioides seeds. Results revealed that warm stratification for 30 days could effectively break dormancy. Seeds pre-treated with gibberellic acid (GA3, 2,000 mg L-1) showed highest germination (63.89 ± 0.91%) as compared to other concentrations of GA3 as well as potassium nitrate (KNO3). Highest in vitro seed germination percentage (65.56 ± 2.92%) was recorded on (Murashige and Skoog) MS medium containing 10 mg L-1 GA3. The viability of the seeds declined with storage period irrespective of its storage condition. After 30 days, highest viability (54.72 %) was observed in seeds stored in moist sand at 25°C. Therefore, application of GA3 and warm stratification (25 ± 1°C) along with a substrate (moist sand) for 30 days may be considered as ideal conditions for effective germination and storage of I. embelioides seeds. This study can also be used for mass propagation of the species for reintroduction in the wild.

Application of Endophytic Trichoderma harzianum to Alleviate the Adverse Impact of Chromium in Lupinus albus L

The present study was conducted to understand the role of interactive usage of Trichoderma harzianum to alleviate the adverse impact of chromium (Cr) stress for sustainable production of the legume plants (Lupinus albus L.) with special reference to physiological mechanism. The exogenous application of T. harzianum significantly enhanced seed germination and plant growth, along with all physiological and biochemical attributes examined in lupin plant. The germination percentage of lupin seeds treated with conidia suspension of T. harzianum was 100% with 37% increase as compared to the control. T. harzianum inoculation increased seedling height (41.3%) and root length (75.6%). Treatment of T. harzianum also resulted in significant enhancement in the photosynthetic attributes like chlorophyll pigment synthesis (13.75% increase as compares to the control), reflecting a significant enhancement in the net photosynthetic rate. Results of our study demonstrated that L. albus have improved tolerance to inhibitory concentrations of Cr when inoculated with T. harzianum. So, we suggest the application of T. harzianum, which could be used to improve the quality and yield of lupin (L. albus) plants in Cr-contaminated areas and in fertile soils.

Salt and Water Stress Tolerance in Ipomoea purpurea and Ipomoea tricolor, Two Ornamentals with Invasive Potential

Invasive plants pose a significant threat to biodiversity, especially under the current unstable climatic conditions. This study aimed to test the salt and drought tolerance of two ornamental species of the genus Ipomoea during germination and vegetative growth. Germination tests were performed in the presence of increasing NaCl concentrations or iso-osmotic PEG concentrations—to mimic the osmotic stress caused by drought. Both species showed great invasive potential because of their high seed germination percentages and rapid germination under control (distilled water) and salt stress conditions, up to 200 mM NaCl. Germination and early seedling development were more affected in the presence of PEG. Subsequently, water stress (complete withholding of irrigation) and salt stress (watering with 100 mM and 200 mM NaCl) treatments were applied to young plants for three weeks, when all plants were harvested, to determine several morphological and biochemical parameters. Both species were sensitive to water deficit but relatively resistant to salt stress. Their salt stress responses were similar, based mainly on the inhibition of Na+ and the activation of K+ transport from roots to leaves and the uptake and accumulation of Ca2+; however, I. tricolor showed a slightly higher tolerance to salt stress than I. purpurea. Although I. tricolor has only been locally reported as invasive and is generally considered a ‘low-risk’ species, our results indicate that it may have an invasive potential even higher than I. purpurea, a recognised invasive weed, spread into areas with moderate salinity, affecting agricultural land or natural habitats of ecological interest.

Methylglyoxal improves zirconium stress tolerance in Raphanus sativus seedling shoots by restricting zirconium uptake, reducing oxidative damage, and upregulating glyoxalase I

Raphanus sativus also known as radish is a member of the Brassicaceae family which is mainly cultivated for human and animal consumption. R. sativus growth and development is negatively affected by heavy metal stress. The metal zirconium (Zr) have toxic effects on plants and tolerance to the metal could be regulated by known signaling molecules such as methylglyoxal (MG). Therefore, in this study we investigated whether the application of the signaling molecule MG could improve the Zr tolerance of R. sativus at the seedling stage. We measured the following: seed germination, dry weight, cotyledon abscission (%), cell viability, chlorophyll content, malondialdehyde (MDA) content, conjugated diene (CD) content, hydrogen peroxide (H2O2) content, superoxide (O2•−) content, MG content, hydroxyl radical (·OH) concentration, ascorbate peroxidase (APX) activity, superoxide dismutase (SOD) activity, glyoxalase I (Gly I) activity, Zr content and translocation factor. Under Zr stress, exogenous MG increased the seed germination percentage, shoot dry weight, cotyledon abscission, cell viability and chlorophyll content. Exogenous MG also led to a decrease in MDA, CD, H2O2, O2•−, MG and ·OH, under Zr stress in the shoots. Furthermore, MG application led to an increase in the enzymatic activities of APX, SOD and Gly I as well as in the complete blocking of cotyledon abscission under Zr stress. MG treatment decreased the uptake of Zr in the roots and shoots. Zr treatment decreased the translocation factor of the Zr from roots to shoots and MG treatment decreased the translocation factor of Zr even more significantly compared to the Zr only treatment. Our results indicate that MG treatment can improve R. sativus seedling growth under Zr stress through the activation of antioxidant enzymes and Gly I through reactive oxygen species and MG signaling, inhibiting cotyledon abscission through H2O2 signaling and immobilizing Zr translocation.

Flower bagging affects seed quality and dormancy period in Na-Oogst tobacco (Nicotiana tabacum L. var H-382)

Seeds of tobacco plants are unable to germinate immediately after harvest because they have a dormancy period. The seed dormancy period may be shortened by bagging methods to affect the hormone content in the seeds. The bagging flower makes the dark conditions in the process of flowering and seed development, affecting the content of the hormone’s auxin and ABA. This study aimed to determine the effects of different bag colors on the dormancy period of tobacco seeds as evidenced by their vigor and viability. The research was conducted from March to August 2022 at PT. Dwi Light Tobacco Green House, Lombok Wetan, Bondowoso, Indonesia. Four crepe colors of paper were used as bagging treatments (black, red, yellow, blue) and control (without bagging) and replicated four times. The results showed that the bagging treatment significantly affected one hundred-seed weight, seed germination, seed growth rate, and seedling height. Black crepe paper resulted in the highest seed germination percentage (98.5%) and seed growth rate (11.68). &#x0D; Keywords: bag color, seed germination, viability, vigor

WEAK SEED DORMANCY 1, an aminotransferase protein, regulates seed dormancy in rice through the GA and ABA pathways

Seed dormancy is a critical trait that enhances plant survival by preventing seed germination at the wrong time or under unsuitable conditions. Lack of seed dormancy in rice can lead to pre-harvest sprouting on mother plants leading to reduced yield and seed quality. Although some genes have been identified, knowledge of regulation of seed dormancy is limited. Here, we characterized a weak seed dormancy mutant named weak seed dormancy 1 (wsd1) that showed a higher seed germination percentage than the wild-type following the harvest ripeness. We cloned the WSD1 encoding an aminotransferase protein using a MutMap approach. WSD1 was stably expressed after imbibition and its protein was localized in the endoplasm reticulum. A widely targeted metabolomics assay and amino acid analysis showed that WSD1 had a role in regulating homeostasis of amino acids. PAC treatment and RNA-seq analysis showed that WSD1 regulates seed dormancy by involvement in the GA biosynthesis pathway. GA1 content and expression of GA biosynthesis-related genes were increased in the wsd1 mutant compared with the wild-type. The wsd1 mutant had reduced sensitivity to ABA. Our overall results indicated that WSD1 regulates seed dormancy by balancing the ABA and GA pathways.

Effects of Seed Invigoration Treatments with Bio-priming on Germination, Vigour and Seedling Growth in Black Gram (Vigna mungo L.)

A study had been conducted in black gram to observe the effect of different seed invigoration treatments with bio-priming for seed germination, seedling growing and vigour. The variety of black gram i.e., Uttara, was selected and seed had been treated with control (T1); Seeds soaked in distilled water/ hydropriming (T2); Rhizobium leguminosarum 10% (T3); Rhizobium leguminosarum 15% (T4); Rhizobium leguminosarum 20% (T5); Rhizobium leguminosarum 25% (T6); Rhizobium leguminosarum 30% (T7) respectively. Treated seeds were grown in different glass plate and patri plate at Seed Testing Laboratory, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, Nadia, West Bengal, India. Seed invigoration with Rhizobium leguminosarum at 20% followed by T4 was found very effective for seed germination with vigorous seedlings. Higher seed germination percentage (82.60), shoot length (17.89 cm), root length (12.99 cm), seedling fresh weight (1.87 g), seedling dry weight (0.19 g), seedling vigour index I (2393.62) and seedling vigour index II (15.96) results were observed for the seed bioprimed with Rhizobium leguminosarum at 20%. Seed treatment with Rhizobium leguminosarum at 20% recorded better performance than rest the treatments for all characters observed. The present investigation clearly depicted that the germination, vigour and seedling growth revalidated seed lots can be improved by pre-sowing and invigoration treatments.

Priming of Citrullus lanatus var. Colocynthoides seeds in seaweed extract improved seed germination, plant growth and performance under salinity conditions

Citrullus lanatus var. Colocynthoide “Gurum” is an unconventional crop that can be utilized as a new source of edible oil and has the ability to grow in a variety of harsh conditions. To mitigate the adverse effects of salinity on seed germination and plant performance of C. lanatus, seeds were primed in the aqueous extracts of the seaweed Ulva lactuca before planting under greenhouse conditions. The aqueous extract of U. lactuca at 8% w/v led to maximal seed germination percentage and seedling growth of C. lanatus. Moreover, U. lactuca extract counteracted the negative effects of salt stress on the plant by significantly increasing the activity of SOD, CAT, and POD. The bioactive components of U. lactuca, e.g. glycine betaine and phenolic compounds can account for such beneficial role of algal extract on C. lanatus. Thus, priming of C. lanatus seeds in U. lactuca extract with various concentrations of U. lactuca extract can be employed as an effective practice for successful seed germination, improved plant growth and enhanced salt resistance, probably as a result of increased antioxidant enzymes activity and photosynthetic pigments.

Integrated management of seed borne pathogenic fungi of different varieties of cotton (Gossypium hirsutum L.)

Single and combined doses of fungicides, plant extracts, and antagonists were used to control of nine cotton pathogens through a pot experiment. A total of 19 treatments, and controls with or without inocula of the pathogen were tested. Out of 19 treatments, T1 (Tilt) and T11 (Tilt + Azadirachta indica + Trichoderma viride) exhibited maximum seed germination and seedling vigor index against Aspergillus flavus, A. niger, Curvularia lunata, Fusarium nivale, Mucor sp. and A. tamarii, Colletotrichum gloeosporioides, F. moniliforme, Rhizoctonia solani respectively. T5 (T. viride), T10 (Tilt + Psidium guajava + T. viride) and T14 (Tilt + A. indica) showed promising germination percentage and seedling vigor index against A. flavus, R. solani and A. tamarii, F. nivale and A. niger, C. gloeosporioides, C. lunata, F. moniliforme, Mucor sp. respectively. Among all the treatments, the combined use of Tilt + A. indica + T. viride showed the best results for reducing the growth of the test pathogens and increasing the germination percentage of seeds. J. Asiat. Soc. Bangladesh, Sci. 49(1): 27-42, June 2023

α-naphthaleneacetic acid positively regulates soybean seed germination and seedling establishment by increasing antioxidant capacity, triacylglycerol mobilization and sucrose transport under drought stress

Drought stress is an important constraint for the germination of soybean (Glycine max [L.] Merr.) seeds and seedling establishment. A pot experiment was conducted to determine the effects of priming soybean seeds with 5 μM α-naphthaleneacetic acid (NAA) and the mechanism responsible for the induced tolerance of drought stress (soil relative water content of 55%). NAA priming inhibited drought-induced oxidative damage in seeds, and further analysis indicated that it induced an early spike in hydrogen peroxide content by the upregulation of abscisic acid-dependent GmRbohC2, resulting in an enhancement of antioxidant capacity. Moreover, NAA priming also improved the hydrolysis of triacylglycerol (TAG) to sucrose in stressed cotyledons by causing a 2- to 5-fold increase in the transcript levels of GmSDP1, GmACX2, GmMFP2, GmICL, GmMLS, GmGLI1, GmPCK1, GmFBPase1, GmSPS1 and GmSPS2. Consistently, it upregulated the expression levels of GmSUT1, GmCWINV1 and GmMST2 under drought stress, thus enhancing the transport of sucrose from cotyledons to embryonic axes, providing carbon skeletons and energy for axis growth. The seed germination percentage increased by 208.1% at 21 h after sowing, and seedling establishment percentage increased by 47.8% at 14 days after sowing. Collectively, the positive effects of NAA priming on seed germination and seedling establishment can be attributed to enhanced antioxidant ability in seeds, TAG mobilization in cotyledons and sucrose transport from cotyledons to embryonic axes under drought stress.

Plant-Derived Smoke Mitigates the Inhibitory Effects of the Auxin Inhibitor 2,3,5-Triiodo Benzoic Acid (TIBA) by Enhancing Root Architecture and Biochemical Parameters in Maize.

The present study was designed to investigate and compare the effects of plant-derived smoke (PDS) and auxin (IAA and IBA) on maize growth under the application of 2,3,5-triiodo benzoic acid (TIBA). For this purpose, indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA), each at a concentration of 10 ppm, along with PDS at a ratio of 1:500 (v/v) were used alone and in combination with 10 ppm of TIBA. The results indicate that the germination percentage (%) of maize seeds was enhanced under IAA, IBA and PDS treatment. However, IAA and IBA resulted in reduced germination when applied in combination with TIBA. Importantly, the germination percentage (%) was improved by PDS under TIBA treatment. The analysis of seedling height, length of leaves, and number of primary, seminal and secondary/lateral roots showed improvement under individual treatments of IAA and IBA, PDS and PDS + TIBA treatment, while these values were reduced under IAA + TIBA and IBA + TIBA application. Chlorophyll content, total soluble sugars and antioxidative enzymatic activity including POD and SOD increased in seedlings treated with PDS alone or both PDS and TIBA, while in seedlings treated with IAA and TIBA or IBA and TIBA, their levels were decreased. APX and CAT responded in the opposite way-under IAA, IBA and PDS treatment, their levels were found to be lower than the control (simple water treatment), while TIBA treatment with either IAA, IBA or PDS enhanced their levels as compared to the control. These results reveal that PDS has the potential to alleviate the inhibitory effects of TIBA. This study highlights the role of PDS in preventing TIBA from blocking the auxin entry sites.

The Effect of the Electric Current Intensity and its Exposure Duration on the Germination Ratio and some Morphological Qualities of the Albizia Seedlings Albizia lebbek L. Benth

The results of exposing Albizia lebbeck seeds to Albizia lebbeck (L.) Benth to the intensity of electric current and for a different period of exposure to a significant superiority when exposing the seeds to the intensity of an electric current 9A in the percentage of germination % Recipe for the height of seedlings, the diameter of the stem, the number of leaves and the wet and dry weight of the vegetative total compared to the comparison treatment, while the duration of exposure exceeded 9 minutes in the characteristic of the height of seedlings, as for the effect of bilateral overlap, the exposure of the seeds to the intensity of the electric current 9A for 9 minutes led to a significant superiority in the percentage of germination % Compared to the comparison treatment, the same treatment also gave a strong 9 for 9 minutes the highest increase in the trait of the rate of rise of seedlings, the diameter of the seedlings, the number of leaves, the wet and dry weight of the vegetative total compared to the comparison treatment that gave the lowest values. From the evidence of the results, we infer that the treatment with electric current led to an increase in the seed germination percentage and improved some of the vegetative growth qualities of the Albizia lebbek.

Study on the effect of chemical and physical mutagen on seed germination of Indian mustard

Indian mustard [Brassica juncea (L) Czern &amp; coss.] is considered as one of the most important vegetable oil and protein meal crops in the Indian subcontinent. Seeds of Indian Mustard Brassica juncea (L) cultivars Shivani and Pusa Bold were treated with EMS (0.3%) and gamma rays (900-1100 Gy) to study germination and other quantitative traits. Gamma rays as a kind of ionizing radiation represent a physical mutagen that induces mutations and may be effectively used in plant breeding. Ethyl methanesulfonate (EMS) is a chemical extensively used to set off mutations at loci that adjust economically vital traits. During these experiments, we observed seed germination percentage in the M1 generation was highest in Pusa Bold then followed by Shivani. An increase in doses of gamma rays and the concentration of EMS reduced the percentage of germination.