Aged Seeds Research Articles

Ultrasonic Waves Regulate Antioxidant Defense and Gluconeogenesis to Improve Germination From Naturally Aged Soybean Seeds.

Soybean seeds contain substantial triacylglycerols and fatty acids that are prone to oxidation during storage, contributing to the dramatic deterioration of seed vigor. This study reports an ultrasonic waves treatment (UWT), which is a physical method capable of promoting the germination ability of the aged soybean seeds by regulating the antioxidant defense and gluconeogenesis. Germination test revealed that UWT significantly increased the germination rate and seedlings’ establishment of the soybean seeds stored for 12 months, although insignificantly impacting the vigor of fresh (stored for 1 month) and short-term stored (for 6 months) seeds. Further biochemical analysis revealed that UWT decreased the hydrogen peroxide (H2O2), O2⋅–, and malondialdehyde contents in the aged soybean seeds during early germination. Consistently, UWT prominently elevated the activities of superoxide dismutase, catalase, and acetaldehyde dehydrogenase, and also the corresponding gene expressions. Besides, the soluble sugar content of UWT was significantly higher than that of the untreated aged seeds. Analysis of enzyme activity showed UWT significantly upregulated the activities of several key enzymes in gluconeogenesis and the transcription levels of corresponding genes. Moreover, UWT enhanced the invertase activity within aged seeds, which was responsible for catalyzing sucrose hydrolysis for forming glucose and fructose. In summary, UWT improved germination and seedlings establishment of aged soybean seeds by regulating antioxidant defense and gluconeogenesis. This study expands the application of ultrasonication in agricultural production and further clarifies the physiological and molecular mechanisms of the aged seed germination, aiming to provide theoretical and practical guidance for seed quality and safety.

Impact of seed priming on germination performance of fresh and aged seeds of Canola

Priming fresh and naturally aged canola seeds with different substances and observing the seed germination properties are involved in this work. Fresh seeds and aged seeds of canola cv. “süzer” were treated with distilled water, -0.8 MPa polyethylene glycol (PEG) 6000 and 50 mM thiamine for 8 hours. Storage of canola seeds showed the loss of germination capacity compared to fresh seeds. Present findings indicate that priming can improve germination and germination speed both in fresh and aged seeds of canola. Germination percentage increased in aged seeds with distilled water priming and thiamine priming. Mean germination times were lower in the primed seeds. Seedling growth didn’t improve with priming in both ages. It was concluded that germination performance improvement of aged seeds is possible with suitable priming.

Dynamic Responses of Antioxidant and Glyoxalase Systems to Seed Aging Based on Full-Length Transcriptome in Oat (Avena sativa L.).

Seed aging is a major challenge for food security, agronomic production, and germplasm conservation, and reactive oxygen species (ROS) and methylglyoxal (MG) are highly involved in the aging process. However, the regulatory mechanisms controlling the abundance of ROS and MG are not well characterized. To characterize dynamic response of antioxidant and glyoxalase systems during seed aging, oat (Avena sativa L.) aged seeds with a range of germination percentages were used to explore physiological parameters, biochemical parameters and relevant gene expression. A reference transcriptome based on PacBio sequencing generated 67,184 non-redundant full-length transcripts, with 59,050 annotated. Subsequently, eleven seed samples were used to investigate the dynamic response of respiration, ROS and MG accumulation, antioxidant enzymes and glyoxalase activity, and associated genes expression. The 48 indicators with high correlation coefficients were divided into six major response patterns, and were used for placing eleven seed samples into four groups, i.e., non-aged (Group N), higher vigor (Group H), medium vigor (Group M), and lower vigor (Group L). Finally, we proposed a putative model for aging response and self-detoxification mechanisms based on the four groups representing different aging levels. In addition, the outcomes of the study suggested the dysfunction of antioxidant and glyoxalase system, and the accumulation of ROS and MG definitely contribute to oat seed aging.

INFLUENCE OF RED LASER RADIATION ON THE VIGOR OF TOMATO SEEDS AFFECTED BY AGING

The loss of vigour in tomato seeds (Solanum lycopersicum L.) due to aging is a normal condition. This study provides a future reference in regard to the possible applications pre-sowing of red laser radiation treatments on tomato seeds to improve the vigour of the aged seeds. The objective of the study was to analyse the effects of laser radiation on aged tomato seeds, on the rate of germination and growth. It is hypothesized that at least one treatment of red laser radiation could improve the seed vigour. Two groups of seeds were used, one with 11 years of aging and another with seeds aged 11 years plus 24 h of artificial aging. For the radiation, a red laser diode of 660 nm was used with a potency of 100 mW, at a radiation density of 0.2 mW cm-2, eight exposure times to the laser radiation and a control. The data were subjected to an analysis of variance and the means were compared with the Tukey test (HSD; p ≤ 0.05). In seeds with 11 years of aging, the laser treatment at 120 s improved seed vigour by 125 %, resulting from an increase in the growth of the radicle (167 %, p ≤ 0.05) compared to the control (100 %). On the other hand, the laser treatment at 60 s improved the tolerance to stress from artificial aging, the vigour index increased 143 % compared to the control (100 %), as a result of an improvement in germination of 162 % and in the hypocotyl growth (130 %, p ≤ 0.05), compared to the control (100 %). Red laser radiation on tomato seeds affected by natural or artificial aging can influence the processes of photo morphogenesis and increase seed vigour.

Imbibition-induced changes in cell membrane on germination and some physiological parameters in aged cress (Lepidium sativum L.) seeds

The deterioration of cellular membranes is the natural phenomenon in seeds exposed to aging. Physiological changes, such as accumulation of reactive oxygen species, mitochondrial dysfunction, and loss of essential metabolites, suppressed antioxidant defense system, and lipid peroxidation occur during the process of seed aging. In the present study, the physiological changes in aged cress seeds and seeds imbibed under different temperatures after aging were examined. In this regard, an array of analysis concerned with the cell membrane leakages and seed viability was performed. For comparison, accelerated aged seed lots with high, intermediate and low viability were used, in relation to the control (not subjected to short-term imbibitions). Accordingly, while the viability in control varied between 43% and 86%, the viability rates of the aged seeds ranged from 41% to 90%. Furthermore, imbibition increased the antioxidant capacity in aged seeds and reduced the lipid peroxidation level, and consequently, reduced the amount of K2+, P3+, Ca2+, Na+ ions, soluble sugar, total protein and amino acids in the solute leakage. Hence, this method might be considered as simple, fast, cost-efficient, nondestructive and applicable in many seed lots at the same time.

Ameliorative effect of priming on germination potential of aged seeds of flowering winter annuals

Ameliorative effect of priming on germination potential of aged seeds of flowering winter annuals

The Opposite Roles of White Light in Regulating Germination of Fresh and Aged Seed in Tobacco.

Light is one of the important environmental factors for seeds to evaluate whether the natural environment is appropriate for germination and subsequent seedlings emergence. The mechanism of light-mediated germination is mainly concerned with fresh seeds (FS) of model plants but is poorly understood in aged seeds. Here, the effects of light on germination of FS and naturally aged seeds (NAS) in tobacco and their relationship with plant hormones gibberellins (GA) and abscisic acid (ABA) were investigated. The results demonstrated that light promoted and inhibited the germination of FS and NAS, respectively. GA and ABA were involved in the germination control of NAS, as well as in FS. However, light suppressed GA signal and stimulated ABA signal in NAS, whereas it stimulated GA signal and suppressed ABA signal in FS. In addition, light stimulated the GA accumulation and reduction in ABA in FS while inhibiting the increase in GA level in NAS. Together, the present study demonstrates that light has opposite effects on the germination of FS and NAS, which are closely related to the metabolism and/or signaling of plant hormones ABA and GA.

Integrated proteome and lipidome analysis of naturally aged safflower seeds varying in vitality.

Seed ageing has an important effect on germination and productivity. During natural ageing, seed vigour decreases rapidly but, to date, the molecular mechanisms underlying this decrease have not been fully elucidated. Using omics, some of the details regarding seed vigour decline during natural ageing might be elucidated through integrated analysis. Safflower seed germination and physio-biochemical changes during natural ageing (stored for 4, 16 and 28 months) were determined. Proteome and lipidome profiling during natural seed ageing was performed, and the differentially expressed proteins and lipid metabolite species analysed. The surface and internal structures of cotyledons were observed. An integrating analysis of the proteome and lipidome was also carried out. Natural seed ageing significantly decreased safflower seed germination and vigour. 4,184 proteins and 1,193 lipids were quantified, both of which show huge differences among the different naturally aged seeds. The surface of the cotyledons collapsed and cracked, and the oil bodies become looser during natural ageing. The total content of DAG and PA increased, while the content of TAG and PL (PC, PE, PS, PI and PL) significantly decreased during seeds ageing. Two lipase genes (HH-026818-RA and HH-025320) likely participated in this degradation of lipids. We conclude that the enzymes that participate in glycerolipid metabolism and fatty acid degradation probably lead to the degradation of oil bodies (TAG) and membrane lipids (PC, PE, PS, PI, PG) and, ultimately, destroy the structure, causing a decline in seed vigour during natural seed ageing.

Seed viability and fatty acid profiles of five orchid species before and after ageing.

Changes in seed lipid composition during ageing are associated with seed viability loss in many plant species. However, due to their small seed size, this has not been previously explored in orchids. We characterized and compared the seed viability and fatty acid profiles of five orchid species before and after ageing: one tropical epiphytic orchid from Indonesia (Dendrobium strebloceras), and four temperate species from New Zealand, D. cunninghamii (epiphytic), and Gastrodia cunninghamii, Pterostylis banksii and Thelymitra nervosa (terrestrial). Seeds were aged under controlled laboratory conditions (3-month storage at 60% RH and 20 °C). Seed viability was tested before and after ageing using tetrazolium chloride staining. Fatty acid methyl esters from fresh and aged seeds were extracted through trans-esterification, and then analysed using gas chromatography-mass spectrometry. All species had high initial viability (>80%) and experienced significant viability loss after ageing. The saturated, polyunsaturated, monounsaturated and total fatty acid content decreased with ageing in all species, but this reduction was only significant for D. strebloceras, D. cunninghamii and G. cunninghamii. Our results suggest that fatty acid degradation is a typical response to ageing in orchids, albeit with species variation in magnitude, but the link between fatty acid degradation and viability was not elucidated. Pterostylis banksii exemplified this variation; it showed marked viability loss despite not having a significant reduction in its fatty acid content after ageing. More research is required to identify the effect of ageing on fatty acid composition in orchids, and its contribution to seed viability loss.

Pectin acetylesterase 8 influences pectin acetylation in the seed coat, seed imbibition, and dormancy in common bean (Phaseolus vulgaris L.)

AbstractThe results of a prior transcript profiling study identified a large difference in transcript accumulation of a pectin acetylesterase gene, designated as PAE8, in two genetically related lines of common bean (Phaseolus vulgaris). The results of reverse transcription‐quantitative PCR experiments confirmed this difference and revealed that the gene is expressed specifically in the seed coat of developing seeds. Genomic sequence data identified a non‐functional allele, due to a five‐base pair insertion resulting in a frameshift and premature stop codon. The non‐functional pae8 allele was associated with a lack of detectable protein as determined by Western blot. PAE8 accounted for approximately 65% of total pectin acetylesterase activity in the developing seed coat. Lack of functional PAE8 resulted in an approximately 2.5‐fold increase in acetylation of soluble pectin in the mature seed coat. The presence of a non‐functional pae8 allele was associated with an increased rate of water absorption by the seed and increased percentage of germination in aged seeds. The data suggest that the decreased acetylation of pectin leads to enhanced interaction with Ca2+, contributing to water impermeability.

Effect of priming and storage containers on seed quality of barley (Hordeum vulgare L.)

The study was conducted on seeds of three two-rowed varieties viz. BH 885, DWRB 92 and DWRB 101 and three six-rowed rowed barley varieties viz. BH 946, BH 393, BH 902 at CCS HAU, Hisar, during 2020-21. Nine months naturally aged seeds were primed with GA 3 (50, 100 and 150ppm), Ethanol (1, 3 and 5%) and ZnO nano-particles (50, 100 and 150ppm). Primed seeds were stored in ordinary (Cloth bags) and moisture-proof (Polythene bags>700gauge thickness) containers under ambient conditions. The results revealed that seed primed with ZnO 100ppm recorded the lowest electrical conductivity (166.59 and 147.93µS/cm/seed) whereas seeds primed with ethanol 5% recorded maximum (181.26 and 162.59 µS/cm/seed) in cloth and polythene bag, respectively. The highest electrical conductivity was recorded in BH 902 (201.90 and 182.03µS/cm/seed) in cloth and polythene bags, respectively while minimum in BH 393 (153.70 µS/cm/seed) in cloth bag and in BH 885 (126.73 µS/cm/seed) in polythene bag. Maximum germination (91.00 and 92.5%), seedling length (30.61 and 33.58cm) seedling dry weight (306.67mg and 282.33), vigour index-I (2800 and 3118) and vigour index-II (23650 and 21048) were observed in primed seeds with ZnO 100ppm while minimum germination (85.83 and 89.33%), seedling length (22.64 and 24.23cm), seedling dry weight (181.97mg and 189.44mg), vigour index-I (1958 and 2170) and vigour index-II (15557 and 16923) were in ethanol 5% in cloth and polythene bag respectively. Among varieties, DWRB 101 recorded highest germination percentage (93.17 and 94.10%) while BH 885 recorded minimum (79.57 and 82.43%) in cloth and polythene bag, respectively. Maximum seedling length (28.24 and 31.31cm) was recorded in BH 946 and minimum (26.02 and 29.11cm) was in BH 902. Maximum dry weight was observed in DWRB 92 (264.97mg and 254.73mg) in cloth and polythene bag respectively while minimum was observed in BH 946 (207.07mg) in cloth bag and DWRB101 (180.53mg) in polythene bag. The highest vigour index-I (2595) was found in the BH 946 in cloth bag followed by DWRB 92 (2938) in polythene bag and minimum was observed in BH 885 (2120 and 2402) in cloth and polythene bag, respectively. Maximum vigour index-II (23748 and 22662) was recorded in DWRB 92 in cloth and polythene bags, respectively and minimum was recorded in BH 885 (18232) in cloth bag and in DWRB 101 (16982) in polythene bag. It is concluded that Polythene bags (with thickness >700gauge) are more suitable to maintain the seed quality of barley as compared to cloth bags. DWRB 101 and BH 946 performed better in all the seed quality parameters indicating highly vigourous cultivars which can be used for further breeding programmes. Seed quality of barley can be enhanced through priming with ZnO 100ppm and GA 3 100ppm.

Discriminant analysis and comparison of corn seed vigor based on multiband spectrum

Seed vigor is an important factor determining the viability of seeds, which is related to many seed-internal components. The vitality of seeds can be identified by assessing the internal information of seeds. In this study, seeds of the sweet corn variety “TuxpenoSweet” were used. Visible and near-infrared spectral ranges were assessed to explore the viability of seeds under different processing methods, and variable selection algorithms were used to optimize models. Heat damaged and artificially aged seeds were compared with normal seeds, and two spectrometers with different band widths were used to collect the spectra of seeds. Seed discrimination models were established based on full-wavelength data and effective variables were selected through competitive adaptive reweighted sampling. The discrimination accuracy of models based on both spectrometers exceeded 95%, and the discrimination accuracy of the model based on effective variables was higher than or consistent with that of the model established with full wavelengths. The experimental results corroborate the feasibility of using spectral ranges between 500–1100 nm or 1000–1850 nm to discriminate seed vigor. The model based on the effective variables extracted by competitive adaptive reweighted sampling reduces the amount of calculated data and either optimizes or maintains the accuracy of the discrimination rate. Effective variables, extracted from the spectrometer with the spectral range of 500–1100 nm, effectively reduced the test cost and the amount of data while ensuring high seed vigor discrimination accuracy.

Exogenous Antioxidants Enhance Seedling Growth and Yield of Artificially Aged Cabbage and Lettuce Seeds

Aged seeds exhibit compromised vigour in terms of germination, seedling emergence and growth, but this can to some extent be alleviated by invigoration treatments before sowing. This study aimed to investigate ageing rates and patterns in cabbage (Brassica oleraceae) and lettuce (Lactuca sativa) seeds and whether the beneficial effects of invigorating aged seeds with exogenous antioxidants translate to enhanced seedling performance. Seeds were artificially aged to 25% viability before soaking in 0.4 mM glycerol, 0.6 mM GSH and 0.2 mM trolox for cabbage, and 0.6 mM glycerol, GSH and trolox for lettuce; deionised water served as a control. After 14 days of sowing, seedling emergence percentage, mean emergence time, mean daily emergence, and time taken to 25% emergence were computed. Seedling vigour index, root and shoot dry weight, root:shoot ratio, leaf area, leaf area ratio, and leaf chlorophyll content were assessed 6 weeks after sowing. Furthermore, the photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (E), and chlorophyll fluorescence were measured 6 weeks after sowing. Notably, ageing resulted in the loss of seed vigour and viability at higher rates in lettuce than cabbage. Seed pretreatment with glycerol promoted seedling growth in both species and shoot dry weight in lettuce, while glycerol and GSH enhanced Pn, Gs and E in lettuce. Trolox also enhanced Pn and E in lettuce. The beneficial effects of the antioxidant treatments are thought to be associated with the protection of photosystems from oxidative stress and/or stimulation of enzymes involved in photosynthesis, possibly through an enhanced antioxidant defence system during the early development stages when seedlings are particularly vulnerable to stress.

P-075. A survey on the diagnosis and management of uteroplacental dysfunction in hypertensive disorders of pregnancy in Japan

Seed vigor is an important factor determining the viability of seeds, which is related to many seed-internal components. The vitality of seeds can be identified by assessing the internal information of seeds. In this study, seeds of the sweet corn variety “TuxpenoSweet” were used. Visible and near-infrared spectral ranges were assessed to explore the viability of seeds under different processing methods, and variable selection algorithms were used to optimize models. Heat damaged and artificially aged seeds were compared with normal seeds, and two spectrometers with different band widths were used to collect the spectra of seeds. Seed discrimination models were established based on full-wavelength data and effective variables were selected through competitive adaptive reweighted sampling. The discrimination accuracy of models based on both spectrometers exceeded 95%, and the discrimination accuracy of the model based on effective variables was higher than or consistent with that of the model established with full wavelengths. The experimental results corroborate the feasibility of using spectral ranges between 500–1100 nm or 1000–1850 nm to discriminate seed vigor. The model based on the effective variables extracted by competitive adaptive reweighted sampling reduces the amount of calculated data and either optimizes or maintains the accuracy of the discrimination rate. Effective variables, extracted from the spectrometer with the spectral range of 500–1100 nm, effectively reduced the test cost and the amount of data while ensuring high seed vigor discrimination accuracy.

Non-Destructive Identification of Naturally Aged Alfalfa Seeds via Multispectral Imaging Analysis.

Seed aging detection and viable seed prediction are of great significance in alfalfa seed production, but traditional methods are disposable and destructive. Therefore, the establishment of a rapid and non-destructive seed screening method is necessary in seed industry and research. In this study, we used multispectral imaging technology to collect morphological features and spectral traits of aging alfalfa seeds with different storage years. Then, we employed five multivariate analysis methods, i.e., principal component analysis (PCA), linear discrimination analysis (LDA), support vector machines (SVM), random forest (RF) and normalized canonical discriminant analysis (nCDA) to predict aged and viable seeds. The results revealed that the mean light reflectance was significantly different at 450~690 nm between non-aged and aged seeds. LDA model held high accuracy (99.8~100.0%) in distinguishing aged seeds from non-aged seeds, higher than those of SVM (87.4~99.3%) and RF (84.6~99.3%). Furthermore, dead seeds could be distinguished from the aged seeds, with accuracies of 69.7%, 72.0% and 97.6% in RF, SVM and LDA, respectively. The accuracy of nCDA in predicting the germination of aged seeds ranged from 75.0% to 100.0%. In summary, we described a nondestructive, rapid and high-throughput approach to screen aged seeds with various viabilities in alfalfa.

Effect of storage period on different seed viability parameters in rajmash (Phaseolus vulgaris)

Seed longevity mainly depends on initial seed quality and storage conditions therefore; farmers and gene bank curators need to be aware of the storage potential of rajmash cultivars that contribute to the production of high quality seed during routine germplasm regeneration/multiplication. Consequently, it is important to generate information on seed longevity of rajmash. In the present investigation, 14 high yielding rajmash cultivars were stored for 4 years and periodical germination percent, time to initiate germination (t1), time to achieve 50% germination (t50) and uniformity of germination (U7525; time between 25 and 75 % germination) were recorded. The varieties exhibited the mean germination percentage of 93, 93, 73, 3 and 0.9 when stored for 0, 1, 2, 3 and 4 years, respectively. The results demonstrated that, all the 14 varieties could be safely stored for a minimum period of 1 year at ambient condition. Seven varieties (Arka Komal, IPR 98-5, IPR 98-3-1, HUR 137, HUR 203, HPR 35, Gujarat Rajmash 1) could be stored for 2 years as they demonstrated more than the minimum germination requirement (75%) of Indian Minimum Seed Certification Standard. Storing seeds for extended period not only decreased the final germination percentage, but also increased the time for t1, t50 and t7525, suggesting that use of aged seeds could result into poor field establishment coupled with delayed and non-uniform germination.

Seed longevity and vigour studies in different types of Indian mustard

An experiment was conducted at ICAR-Indian Agricultural Research Institute, New Delhi (2017-18) to study the possible reason for reduced seed vigour in Indian quality mustard genotypes during storage for the first time. Freshly harvested seeds, one year, two year aged seeds and controlled deteriorated seeds of freshly harvested seeds of conventional and quality Indian mustard were used for the study. Reactive oxygen species (ROS), i.e. hydrogen peroxide (H2O2) and superoxide radical (O2 .-) were estimated along with enzymatic antioxidants such as catalase and peroxidase and redox couples ratio (ASC/DHA and GSH/GSSG) in all the nine genotypes of different age group and correlated with germination percentage, mean germination time and seed vigour indices. The experiment revealed that during storage, the amount of ROS accumulation goes on increasing and both enzymatic and non-enzymatic antioxidants goes on decreasing. In comparison to conventional genotypes, quality genotypes were found to contain significantly lower level of antioxidants and significantly higher level of ROS content during the storage period. Germination percentage as well as seed vigour indices were negatively correlated with ROS and positively correlated with enzymatic and non-enzymatic antioxidants. This experiment revealed that reduced vigour in quality genotypes could be due to faster deterioration during the storage due to increased production of ROS.

Invigoration of various sized sunflower seeds: an evaluation of germination and seedling quality parameters under different aging conditions

An experiment was conducted at laboratory of Department of Seed Science and Technology, Institute of Agricultural Science, University ofCalcutta, West Bengal, India to evaluate the response of various sized sunflower seeds (large, medium, small, composite) to invigoration treatments (control, red chilli powder@ 1g/kg of seed, bleaching powder@ 2 g/kg ofseed, aspirin@ 50 mg/kg ofseed) under various aging conditions. Results showed that compared to aged seeds, germination and seedling quality parameters of sunflower were best under fresh seeds. Among aging conditions, naturally aged seeds showed less quality deterioration than seeds under accelerated aging. Irrespective of aging and no aging, large sized seeds treated with either red chilli powder or bleaching powder showed good seedling quality. Specifically, freshly harvested large seeds produced vigorous seedling when treated with red chilli powder (vigour index-I: 1833.88, vigour index-II: 2174.52) or bleaching powder (vigour index-I: 1808.76, vigour index-II: 2200.09). Among two aging conditions, seed quality deterioration was better checked and repairing of damage to an extent was done over control when large seeds were treated with powders specially, red chilli powder (vigour index-I: 1079.61, vigour index-II: 1128.59) or bleaching powder (vigour index-I: 1060.07, vigour index-II: 1053.21) under natural aging condition.

Assessment of rice seed vigour using selected frequencies of electrical impedance spectroscopy

The electrical impedance spectra of fresh and naturally aging rice seeds were measured to develop a non-destructive method for measuring the vigour of such seeds. To this end, three frequencies were selected using the coefficient of variation method within various frequency domains. A prediction model was then established using Fisher linear discriminant analysis, with the impedance, phase angle, and three-dimensional size of the seeds at the selected frequencies as independent variables and fresh and aging seeds as dependent variables. The water states and micromorphology of the seeds were subsequently evaluated to reveal the influence mechanism of impedance and vigour. The results showed that the impedance parameters of fresh and aging seeds were distinguishable, and the difference was evident in the low-frequency region. Moreover, the discriminant analysis model showed good predictive ability; the accuracies of the discriminant functions, Y 1 and Y 5 , were 90%. The impedance variables had a significant influence on the accuracy of the model, and the prediction accuracies for the fresh and aging seeds were improved by 24% and 14%, respectively, through introduction of the independent variables. Additionally, changes in the vigour, water state, and impedance were observed to be interrelated. The moisture content of the aging seeds was mainly affected by the content of bound water, and the ratio of bound water was inversely proportional to the impedance value. The variation in the impedance of the aging seeds was deemed to result from the combined effect of water state and micromorphology. • Electrical impedance spectroscopy parameters can reveal vigor level of rice seeds. • Moisture content of aging seeds is mainly affected by the content of bound water. • Ratio of bound water is inversely proportional to the impedance value. • Impedance variation combined effect of water state and micromorphology.

Influence of Different Priming Materials on Germination and Alpha-Amylase Enzyme of Hybrids Sorghum (Sorghum bicolor L. Moench. x Sorghum sudanense Staph.) Seeds

Germination is considered a critical step in the development cycle of the plant. But no information is available regarding seed priming with Putrescine, Jasmonic acid, Kinetin, Potassium Nitrate (KNO3), Salicylic acid at a time in the aged and non-aged seeds of sorghum cultivars. However, to know the effect of seed priming with the aforesaid chemicals in the aged and non-aged seeds of sorghum cultivars on the germination rate, germination vigour and alpha-amylase activity, research was conducted under laboratory condition, at Field Crops Central Research Institute, Ankara, Turkey. Aged and unaged seeds of Sugar Grazer II and Digestivo hybrid silage sorghum cultivars were used as the seed material of the experiment. Putrescine, Jasmonic acid, Kinetin, KNO3 and Salicylic acid were used as priming chemicals. The results revealed that aged and un-aged seeds of the cultivars showed different responses to similar chemical and KNO3 application to un-aged seeds had a positive effect on germination rate and alpha-amylase, Whereas Jasmonic acid and Putrescine applications had a positive effect on the aged seeds. Priming with putrescine, KNO3 and jasmonic acid showed the best results in the experiment.