Seed Vigor Parameters Research Articles

Genetic variability for early seed vigor traits for enhanced performance under sub-optimum temperatures in sweet corn (Zea mays Convar. saccharata L.)

High germination and seed vigor under sub-optimum temperature is desirable for successful stand establishment in Sweet Corn. Aninvestigation was undertaken to assess the performance of shrunken2 based Sweet Corn hybrids; CMVL Sweet Corn-1 and Pusa SuperSweet Corn-2 and their parental lines; SWT16, SWT17, VSL16 and VSL4 for early seed vigor parameters under sub-optimum (15⁰C, 20⁰C)and optimum (25⁰C) temperature conditions. Among the genotypes, hybrids (CMVL Sweet Corn-1 and Pusa Super Sweet Corn-2) weresuperior than their parental lines for the seed vigor traits like seedling emergence, germination index, mean germination time (MGT),vigor indices, root growth parameters and field emergence under sub-optimum temperature. The inbred lines; SWT16 and SWT17had better performance than VSL16 and VSL4 for seed vigor parameters under sub-optimum temperatures. Seedling root architectureaffected seedling performance and establishment under sub-optimum conditions. In the study, under sub-optimum temperaturesseedling root parameters i.e. the root length, surface area and root volume reduced whereas the root diameter increased in the sweetcorn lines. Vigor index-II (0.87 and 0.78) and MGT (-0.87and -0.54) showed significant correlation with the field emergence of sweet corn genotypes under 15 and 20oC respectively and thus could be the selection indices for identifying sweet corn genotypes with optimum performance under sub-optimum temperature regimes.

Correlation of Germination, Seedling Vigour Indices and Enzyme Activities in Response to Liquid Organic Kunapajala to Predict Field Emergence in Late Sown Wheat

A laboratory experiment was conducted to correlate the germination test with seed vigour parameters and enzyme activities to predict seedling vigour and planting value on late sown wheat variety UP-2526. The experiment was conducted at GBPUA and T, Pantnagar during rabi season of 2020-2. The experiment consisted of five treatments viz; no priming (control), hydropriming, 10%, 25% and 50% kunapajala priming for 16 hrs. Results revealed that germination percentage was positively and significantly correlated with speed of germination (0.914*), seedling vigour index-II (0.890*), α-amylase activity at 12 and 16 hrs of priming (0.942* and 0.947*, respectively), seed reserve mobilization efficiency on 4th day (0.954*) after incubation and imbibition rate after 16 and 24 hrs of soaking duration (0.933* and 0.894*, respectively). Heat stress both low and high temperature are major reason of declining yield in wheat when sown delayed. Prediction of seedling vigour and field emergence of seed before sowing is prime important for assured yield in late sown condition.

Effect of Seed Fortification With GA3 for Quality Seedling Production in Annatto (Bixa orellana L.)

Pre-sowing seed treatments study was designed to evaluate impact of soaking hours and role of GA3 on quality seedling production in Bixa orellana. In the present study seeds soaked in cold water for 18 hours soaking which took 15 days for quick seed vigour in seed germination Accordingly it indicated that 18 hours seed soaking duration treatment has enhanced seed softening, quick seed germination and seedling quality traits than other treatments. Among the treatments, the seeds soaked in GA3 200 ppm for 18 hours recorded the highest values for seedling per cent and other seed vigour parameters and it was followed by GA3 150 ppm. Among the treatments studied,T4 (200 ppm) and T5 (250 ppm) recorded early germination, took 9 days to initiate germination, whereas control (T6 )) took maximum (23.8) days to germinate. Maximum germination registered with GA3 200ppm (T4 - 64.74 %) while minimum was recorded with control (T6 - 13.67 %). It enhance seedling vigour parameters at nursery studied through like root length, shoot length, collar diameter, dry matter production and vigour index of seed fortified with GA3 200 ppm escalated over control. Hence, seed fortification with GA3 200 ppm for 18 hours duration is highly useful and easily adoptable for enhanced quick and high quality seedling production especially by commercial nursery growers on Bixa orellana.

Correlation and R2 analysis of radicle emergence test to predict seed vigour and field emergence in blackgram (Vigna mungo L.) seed lots

Blackgram (Vigna mungo L.) is one of the major pulse crops grown throughout India. Prediction of seed vigour and field emergence of seed before sowing is important for assured yield. A standard germination test is time-consuming and does not always show the seed lot potential performance, especially if field conditions are not optimal. There is need of advanced technology, which can give a precise result in a short period. The experiment was conducted to correlate the radicle emergence test with seed vigour parameters to predict seed vigour and planting value of 10 varying vigour lots (L1, L2, L3, L4 - high vigour lots; L5, L6, L7 - medium vigour lots; L8, L9, L10 - low vigour lots) of blackgram var. VBN 6. The study showed that all the seed vigour parameters of the blackgram were more highly correlated with the percentage of radicle emergence with 2 mm length than with 1 mm length. The correlation analysis results showed that the radicle emergence test with 2 mm radicle length at 28 hours had a highly significant negative correlation with EC (electrical conductivity) of seed leachate (-0.974**), followed by MJGT (mean just germination time) (-0.967**) and MGT (mean germination time) (-0.933**). However, it was positively correlated with field emergence (0.972**), germination (0.952**) and dehydrogenase enzyme activity (0.928**). The maximum R2 value of 0.923 was recorded in the 28-hour counting of radicle emergence with a length of 2 mm compared with the 26-hour counting of radicle emergence with a length of 1 mm (0.913). The study concluded that counting 2 mm radicle emergence at the 28th hour could be used to quickly evaluate seed vigour in field emergence in blackgram seed lots.

Assessment of maize seed vigor under saline-alkali and drought stress based on low field nuclear magnetic resonance

To detect maize seed vigor under salt-alkaline and drought stress conditions, transverse relaxation time, physiological index, and electron microscopy images of germinating seeds were studied under different stress conditions. The results showed that the water in germinating maize seeds exist in bound water (T21), semi-bound water (T22), and free water (T23), in addition parabolic water (T24). The Pearson correlation analysis was performed with T2 relaxation parameters and seed vigor parameters, and this analysis yield nine optimized parameters. To predict vigor levels under different stress conditions, an error backpropagation artificial neural network model was developed, wherein the T2 chirality parameter was used as the input value, and the seed germination indices of different stress levels were used as the output values. The model could predict the environmental stress level of maize seed growth. The optimized parameter set showed a prediction accuracy of 92.50%, thus outperforming the T2 relaxation information model without parameter optimization (75.01%). The proposed method can collect data during the germination of maize seeds without any interference and achieve large-scale prediction of seed development status by small sample collection. With the stress environment was aggravated, the physiological structure of seed cells was changed, and the cell structure was destroyed and the ability of water absorption was disappeared. This analysis provides theoretical support and a reference basis for maize planting and production.

Gibberellic acid biosynthesis during dehydration phase of priming increases seed vigour of tomato

Priming of seed is intended to reduce the time to germination through activation of pre-germinative processes. Seed priming is controlled hydration followed by a drying (dehydration) process. The physiological processes during hydration (imbibition) were studied in detail in tomato. In contrast, gibberellic acid changes during the dehydration phase were not studied in detail. We hypothesize that there would be a change in the GA concentration during the dehydration phase of the seed priming process, which may influence the vigour characteristics of the resultant seedling. The objective of the study was to understand the influence dehydration phase of seed priming on GA biosynthesis and its subsequent effect on seed germination and seedling traits of tomato. First, the hydroprimed and unprimed seeds were re-imbibed for 3 h, 6 h, 9 h, and 12 h to initiate the germination process, and the GA concentration and seedling vigour associated parameters were recorded. In the second experiment, the imbibed seeds were dehydrated for 3 h, 6 h, 9 h, and 12 h, then re-imbibed for 3 h, 6 h, 9 h, and 12 h to understand the effect of dehydration on the GA concentration and its associated traits. Results revealed that hydroprimed seeds had a higher GA concentration and seedling vigour than unprimed seeds. The seeds that are completely dehydrated for 12 h had the highest GA and seed vigour parameters. Therefore, increased vigour of hydroprimed seeds is due to the higher levels of GA accumulated during the dehydration phase of seed priming, which can improve seed germination and seedling vigour of tomato.

Screening of barley (Hordeum vulgare L.) genotypes for tolerance to salt stress

Genotypes of barley were screened under different salinity levels (25, 50, 100, 125, 150, 175 and 200 mM NaCl). The effect of salt stress on seed germination and seedling vigour was investigated through physiological traits. Seeds of ten barley genotypes (BL1400, BL1314, PL890, PL807, RD2552, PL751, BL1430, PL426, BL1375 and BL1367) were treated with different salt concentrations and the experiment was conducted in completely randomized design. Results indicated that increased salinity beyond 100mM and 125 mM NaCl concentration caused a significant reduction in germination percentage and seed vigour parameters in different genotypes. Significant reduction in root and shoot length at seedling stage was also observed. Seedling biomass (fresh and dry weight) also declined with increase in salt concentration as compared to control.

Genetic variability and diversity analysis in wheat (Triticum spp.) genotypes using multivariate techniques

Thirty-four Indian wheat (Triticum spp.) varieties released from 1933 to 2010 were evaluated at CCS Haryana Agricultural University, Hisar (India) for genetic variability and diversity based on their morphological and seed vigour parameters during 2015-16. Significant variations were exhibited by the genotypes for all 26 traits under study. Awn length and dehydrogenase activity had maximum values of genotypic coefficient of variation (GCV), phenotypic coefficient of variation (PCV), heritability and genetic advance as percentage of mean for morphological and seed vigour traits, respectively. In the principal-component analysis of morphological traits, first five principal components accounted for about 77.56% of the total variation. Whereas, first three principal components explained about 84.19% of the total variation for seed vigour parameters. Principal-component analysis score identified variety WH 1105 as most vigorous variety as well potential genotype for morphological traits.

Radicle emergence test as a quick vigour test to predict field emergence performance in rice (Oryza sativa L.) seed lots

An experiment was made to standardize the radicle emergence test to predict the field emergence performance in ten different seed lots [L1 to L4: high vigour lots (> 90 % germination), L5 to L7: medium vigour lots (80-90 % germination) and L8 to L10: low vigour lots (< 80 % germination)] of rice cv. CO 51. The results showed that the significant differences are observed in physiological and biochemical parameters in different seed lots. The seed vigour was classified into three groups viz., high, medium and low vigour based on the relationship between mean germination time and field emergence. When the Mean Germination Time (MGT) was < 34 hours, the field emergence was > 85 per cent, which was considered as high vigour; when the MGT was 34-35 hours, the field emergence was 80-85 per cent, that was considered as medium vigour; when the MGT was > 35 hours, the field emergence was < 80 per cent, that was considered as low vigour. The radicle emergence test (2mm radicle length) was highly negatively correlated with mean germination time (-0.930**) followed by mean just germination time (-0.852**) and electrical conductivity of seed leachate (-0.827**) and it was positively correlated with field emergence (0.894**) followed by germination (0.878**) and dehydrogenase activity (0.864**). The R2 values between seed vigour parameters and radicle emergence test were significantly higher in 2mm length of radicle emergence when compared with 1mm length of radicle emergence. Finally, the study concluded that 36 hour MGT with the attainment of 2mm radicle emergence percentage could be used as a quick method to assess rice seed lots' quality by the seed analysts and seed industry.

Evidence for seed vigor associated with fatty acids and its composition in rice

AbstractAlthough fatty acids (FAs) adversely influence seed vigor in general, knowledge is limited about effects of FAs and its composition on seed vigor of rice (Oryza sativa L.). In this study, seed vigor parameters, FA, and its composition contents of different rice varieties were measured to determine their intrinsic relationships. There were significant differences in germination potential (GP), germination rate (GR), field emergence rate (FER), and FA and its composition contents among different varieties in 2014 and 2015. Additionally, the results of correlation analysis in both years showed that FA content was significantly negatively associated with GP (r = −.66** and r = −.69**, respectively), GR (r = −.72** and r = −.87**, respectively), and FER (r = −.51* and r = −.51*, respectively). Interestingly, the contents of palmitate acid (C16:0), linoleic acid (C18:2), and linolenic acid (C18:3) in both years were significantly negatively related to seed vigor (r = −.43* to −.77**). Moreover, the results of principal component analysis showed that palmitate acid (C16:0), linoleic acid (C18:2), and linolenic acid (C18:3) were main contributions in the first principal component for conventional japonica rice while in the second principal component for hybrid indica rice. These results suggest that medium‐chain FAs account for the decrease of seed vigor. Our study provides an important parameter for seed vigor testing and an early warning sign for seed storage of rice.

Multivariate analysis of seed vigour parameters in late sown wheat (Triticum aestivum L. em. Thell)

An experiment was conducted to determine variability, correlation, path coefficient and principal component analysis for seed vigour parameters viz. standard germination, seedling density, seedling length, seedling dry weight, seedling vigour index I and II, 1000 grain weight and grain yield plot-1. The analysis of variance (ANOVA) revealed a wide range of variation existing in the material studied. The highest phenotypic and genotypic coefficient of variance recorded for seedling vigour index II (21.16 and 20.95, respectively) and, moderate values for seed density, seedling length, seedling dry weight and seedling vigour index I. The maximum value for heritability (broad sense) was found for seedling vigour index II (98.77%) whereas grain yield plot-1 had moderately high heritability (62.09%). Significant positive correlation were reported between standard germination and seedling density, seedling length, seedling dry weight, seedling vigour index I, seedling vigour index II and 1000 grain weight and seedling vigour index I estimated highest direct positive effect on grain yield plot-1, followed by seedling vigour index II, 1000 grain weight and seedling density. The principal component (PC1 and PC2) having Eigen value >1 (significant), accounted 64.70% of total variation. Maximum value was explained by component 1 with 50.5% of total variation.

Systematic trait based identification and characterization of Indian wheat varieties released during different time scales

Aim: Wheat varieties have been developed for yield improvement by modern plant breeding methods from the basic pedigree for long which brought about a restricted hereditary base. Therefore, the present study was designed to develop identification keys and characterize different wheat varieties on the basis of multiple traits. Methodology: Thirty-four Indian wheat (Triticum spp.) varieties released during different time scales were assessed for diversity through various approaches based on morphological, seed vigour, biochemical and molecular characterization.? Results: The results revealed that a considerable amount of variation was present in phenotypic characters such as flag leaf, plant height, spike and yield related characters. Seed vigour parameters included test weight, seedling dry weight, seedling length, accelerated ageing test and vigour indices showed significant variability among varieties. Dehydrogenase activity, tetrazolium test and electrical conductivity of seed leachates were also found worth studying for diversity. Molecular characterization included twenty-one SSRs selected after screening of 45, amplified 46 alleles, among them 42 alleles were polymorphic. PIC value varied from 0.1 to 0.65 and similarity coefficient extended from 0.34 to 0.87. Interpretation: Genetic diversity pattern analysis of genotypes based on their geographical origin did not show any clear relation, however characters like plant height, seed boldness and seedling vigour indices of varieties showed a trend with a chronology of their release. Different perspectives used in the study successfully categorized wheat genotypes into various groups.

Genetic diversity in pearl millet restorers based on seed vigour traits and SSR markers

Thirty four pearl millet restorer lines were evaluated on the basis of nine seed vigour traits and molecular analysis was done with 55 SSRs to study the genetic divergence among them. Cluster analysis based on seed vigour parameters revealed the considerable amount of variability and all genotypes were divided into six clusters. Furthermore, a set of 39 SSRs, selected after initial screening of 55, amplified 226 alleles with a mean of 5.84 alleles per locus. The highest polymorphic information content (PIC) value obtained was for PSMP 2084 (0.88) with a range of 0 to 0.88 and average PIC of 0.558. Neighbor joining tree based on molecular data differentiated all the genotypes into two major groups. The grouping based on both approaches can help breeders to use the studied material in further breeding for improvement of germination potential and early seedling vigour of pearl millet.

Seed filling determines seed vigour of superior and inferior spikelets during hybrid rice (Oryza sativa) seed production

Growth and development of spikelets are asynchronous during hybrid rice seed production. However, knowledge is limited about the variation in seed vigour between superior and inferior spikelets. The main objective of this study was to evaluate the differences in seed vigour between superior and inferior spikelets of hybrid rice, and to explore the mechanisms associated with such variations with regards to seed filling characteristics and starch accumulation. Field experiments were conducted in 2017 and 2018, and seed vigour parameters, seed filling characteristics and starch accumulation were determined. We found that significant differences were recorded in seed vigour parameters between superior and inferior spikelets. Germination percentage (GP) and vigour index (VI) of superior spikelets were higher than that of inferior spikelets, irrespective of year or variety. Moreover, significant differences were observed in seed filling characteristics and starch accumulation between superior and inferior spikelets. Lower total starch content, amylose content and amylopectin content were recorded in inferior spikelets with low seed filling rate and long seed filling duration. Superior spikelets with high seed filling rate and short seed filling duration increased final seed weight by 23.9 and 22.3% for each variety, respectively. Therefore, these results raise the possibility that seed filling influences the starch accumulation and seed weight, and is closely associated with differences in the vigour of seeds from superior and inferior spikelets during hybrid rice seed production.

Seed filling under different temperatures improves the seed vigor of hybrid rice (Oryza sativa L.) via starch accumulation and structure

Seed filling is crucial for seed vigor and starch accumulation and structure. Differences in hybrid rice seed vigor were evaluated in field experiments, conducted across two sites in 2017 and 2018, under different seed filling temperatures along with the underlying mechanisms related to the seed filling characteristics and starch accumulation and structure. Significant differences in the seed vigor parameters were revealed, with different seed filling characteristics observed under different temperatures. When averaged across cultivars, the seeds with a low seed filling rate and long seed filling duration obsessed 11.9% higher germination percentage (GP) and 22.7% higher vigor index (VI) than those with a high seed filling rate and short seed filling duration. Moreover, a high seed filling rate and short seed filling duration significantly decreased the total starch and amylose contents and increased the amylopectin content. Additionally, when averaged across cultivars, the relative crystallinity and starch granule diameter obtained with a high seed filling rate and short seed filling duration were 3.8% and 15.1% higher, respectively, than those with a low seed filling rate and long seed filling duration. In summary, it can be speculated that seed filling characteristics determine hybrid rice seed vigor by affecting starch accumulation and structure.

Effects of Gibberellic Acid Application after Anthesis on Seed Vigor of Indica Hybrid Rice (Oryza sativa L.)

Gibberellic acid (GA3) application after anthesis is an important practice in hybrid rice seed production, and it plays diverse roles in seed quality and seed yield. The main objective of this study was to determine (1) the effects of GA3 application after anthesis on seed vigor and (2) the optimal GA3 dosage applied to Indica hybrid rice seed production. Field experiments of different GA3 dosages (15 g hm−2 and 30 g hm−2, respectively) after anthesis were conducted in 2016 and 2017, and seed vigor parameters, stigma vigor index, and seed yield were determined. We found that significant differences in seed vigor parameters by a standard germination test and a cool germination test were observed among different GA3 dosages after anthesis. Compared with the water spraying treatment, the germination percentage (GP) increased by 2.5–6.3%, and the vigor index (VI) increased by 8.9–19.8% from GA3 application after anthesis, respectively. Moreover, the stigma vigor index of the female parent was enhanced with an increasing GA3 dosage, and there were significant increases (7.5–16.0%) between the water spraying treatment and GA3 spraying treatments. There were positive significant relationships between the VI and stigma vigor index. Additionally, the seed yield of the GA3 application with 30 g hm−2 was 3.9% higher on average than that of the water spraying treatment. Therefore, our study suggests that seed vigor can be increased by GA3 application after anthesis, and GA3 application should be applied at a rate of 30 g hm−2 to improve seed vigor and maintain seed yield in Indica hybrid rice seed production.

Effect of mechanical threshing on damage and vigor of maize seed threshed at different moisture contents

Mechanical threshing used when preparing maize seeds for planting subjects seed to damage and reduces seed quality. The purpose of this study was to assess the effect of mechanical threshing on the quality of maize seed threshed at different moisture contents (MCs). Seeds of dent maize JK968 and flint maize DD2 were threshed at 12, 15, 18, 21, and 24% MC. The damage degree was determined by iodine staining, and seed vigor was assessed by standard germination (SG), cold test germination (CTG), accelerated aging germination (AAG), seedling emergence rate, and seedling root and shoot length. The results showed that the damage percentage increased, and the seed vigor parameters decreased with increasing seed MC during threshing in both cultivars. For obtaining high seed quality, indicated by at least 90, 85, and 80% of SG, AAG, and CTG, respectively, JK 968 and DD2 should be threshed at MC lower than 15 and 18%, respectively. Furthermore, the damage mainly occurred in the apical part of seeds, irrespective of the threshing MC in both cultivars. When the embryo was damaged, seedling emergence rates were significantly reduced with great influence on shoot length. Damage to the endosperm resulted in little effect on seedling performance. Flint maize DD2 was more tolerant to mechanical threshing than dent maize JK968. These results provided technical reference for the production and processing of high vigor maize seeds.

Evaluation of Radicle Emergence Test to Predict Seed Vigor and Field Emergence in Different Seed Lots of Cluster bean (Cyamopsis tetragonoloba L.)

The study was conducted to evaluate and correlate the radicle emergence test with other vigour parameters to predict the seed vigour and field emergence potential in ten seed lots of cluster bean with varying vigour. The results showed that the significant differences were observed among the seed lots in terms of physiological parameters viz., speed of germination, germination percentage (GER), root length, shoot length, dry matter production, vigour index, mean just germination time (MJGT), mean germination time (MGT), radicle emergence (RE) and field emergence (FE) and biochemical parameters viz., electrical conductivity of seed leachate (EC) and dehydrogenase activity (DA). Relationship between seed vigour parameters and radicle emergence per cent with 1mm and 2mm radicle length was also evaluated. The highest R2 values were observed in 2 mm length of radicle emergence per cent (R2 values viz., MJGT = 0.8832, MGT = 0.9379, EC = 0.8320, DA = 0.7810, GER = 0.8323 and FE = 0.8796) compared with 1mm length of radicle emergence per cent (R2 values viz., MJGT = 0.8777, MGT = 0.8826, EC = 0.8107, DA = 0.8113, GER = 0.8292 and FE = 0.8699) for most of the seed vigour parameters in ten different seed lots. The study concluded that counting 2 mm radicle emergence at 32 hours could be used for a quick evaluation to assess the seed vigour in terms of field emergence in cluster bean seed lots.

Effect of Blast Disease on Seed Vigor Parameters in Rice

Effect of Blast Disease on Seed Vigor Parameters in Rice

Effect of Proline and Salicylic Acid on Seed Vigour Parameters in Fresh and Aged Seeds of Radish (Raphanus sativusL.)

In the present investigation, fresh and aged seeds of radish were treated with salicylic acid using 50 mg/L and 100 mg/L and proline 5mM and 10 mM concentrations of each for 12 hr and 24 hr with the objective to enhance the germination and seed vigour of aged seeds. In general aged seeds showed less germination as compared to fresh seeds. All the seed treatments increased the germination percentage and seed vigour I and II in both fresh and aged seeds as compared to control and the effect was maximum when treated with proline 10 mM.