Effect of Exogenous Gibberellin on Wheat Seed Germination under Salt Stress

[Objectives]In this experiment,wheat seeds were treated with different concentrations of gibberellin and different concentrations of salt solution to study the change of germination index of wheat seeds.[Methods]The germination rate,germination potential and germination index of wheat seeds were measured by routine methods,and the effect of exogenous gibberellin on germination of wheat seeds under salt stress was observed.[Results]The germination rate,germination potential and germination index of wheat seeds under salt stress were significantly increased after exogenous treatment of 0.25 and 0.50 g/L gibberellin within the range of salt concentration gradient.However,when the concentration of gibberellin was too high,it would inhibit the germination of seeds.[Conclusions]Appropriate concentration of gibberellin can effectively alleviate the stress caused by salt on wheat seed germination.In this experiment,the best concentration of gibberellin to alleviate salt stress was 0.25 g/L.

Effects of Nitric Oxide on the Germination of Wheat Seeds and Its Reactive Oxygen Species Metabolisms Under Osmotic Stress

Effects of sodium nitroprusside (SNP), a nitric oxide (NO) donor, on the germination and metabolism of reactive oxygen species were surveyed in wheat (Triticum aestivum L.) seeds. Germination of wheat seeds and even the elongation of radicle and plumule were dramatically promoted by SNP treatments during the germination under osmotic stress. Meanwhile, activities of amylase and EP were enhanced, thus leading to the degradation of storage reserve in seeds. After osmotic stress was removed, higher viability of wheat seeds was also maintained. In addition, the activities of CAT, APX and the content of proline were increased by SNP treatment simultaneously, but activities of LOX were inhibited, and both of which were beneficial for improving the antioxidant capacity during the germination of wheat seeds under osmotic stress. It was also shown that the increase of the activity of amylase induced by SNP in embryoless half-seeds of wheat in the beginning period of germination (6 h) might be indirectly related to GA(3).

Effects of Used Battery on Key Enzyme Activity during the Germination of Wheat Seeds

[Objective] This study aimed to explore the effects of used battery lixivium on wheat germination. [Method] The wheat seeds were treated with used battery lix- ivium at different concentrations to detect the change of activities of amylase, pro- tease, pyruvate dehydrogenase （PDH） and polyphenol oxidase （PPO） during the ger- mination period. [Result] The results showed that the used battery affected enzyme activity. With the increase of concentration of used battery lixivium, trends of the changes of amylase and protease activities were not different. The activities were en- hanced at low concentrations of lixivium, while were inhibited at high concentrations. The tends of changes of pyruvate dehydrogenase （PDH） and polyphenol oxidase （PPO） activities were not consistent with that of either amylase or protease, which showed continuous downward trends with the increasing concentration of used battery lixivium. [Conclusion] This study is of great practical significance for understanding the effects of used battery lixivium on the germination of wheat seeds.

Preparation of a Novel Highly Effective and Environmental Friendly Wheat Seed Coating Agent

A novel environmental friendly wheat seed coating agent was prepared from the natural polymer,biological pesticide,microfertilizer,microelements and other additives.The laboratory and field test results showed that it could enhance the yield up to 16% and reduce its input cost to 1/6 as compared with the conventional wheat seed coating agent.It is safe without causing any pollution and would have significant economic and environmental benefits.

Proteomic Analysis of Wheat Seed in Response to Drought Stress

Drought stress is one of the major factors affecting in wheat yield and grain quality. In order to investigate how drought stress might influence wheat quality during grain filling, three wheat cultivars Gaocheng 8901, Jagger and Nongda 3406 were subjected to drought stress during the grain filling stage. Neither globulin and glutenin, nor the relative percentage ofamylose significantly changed following drought treatments, whereas albumin and gliadin concentrations did. The SDS-sedimentation, which has a strong linear correlation with wheat baking quality was markedly decreased following drought stress. These results indicated that drought had an adverse effect on wheat qualit3,. In order to investigate the protein complexes in the wheat flour, the data from native PAGE and SDS-PAGE were combined and a total of 14 spots were successfully identified, and of these eight protein types were determined to be potential complex forming proteins.

Detection of Aflatoxin from Some Aspergillus sp. Isolated from Wheat Seeds

Ten seed borne fungi （Alternaria sp., Aspergillus sp., Aureobasidium sp., Cladosporium sp., Dreschslera sp., Penicillium sp., Rhizoctonia sp., Stemphylium sp., Mueor sp. and Rhizopus sp.） were isolated and identified from two wheat varieties, the highest frequency of seed borne fungi was observed on wheat cultivar site Moll4 Alternaria sp.. Their mean and standard deviation was （5.5 ~ 1.69） while the lowest frequency fungal isolated was Dreschslera sp. and Rhizopus sp.. Their mean and standard deviation was （0.1 ~ 0.64）. The aflatoxin-producing isolates appeared as gray or black colonies in the UV photographs, whereas nonproducing isolates appeared as white colonies, the plate five colony four （P5CO4） showed the positive results which means the presence of aflatoxin as compaired to the control which showed the ngative results. Ammonium Hydroxide Vapor-Induced Color Change method used which the dish was inverted and 1 or 2 drops of concentrated ammonium hydroxide solution are placed on the inside of the lid. The undersides of aflatoxin-producing colonies quickly turn plum-red after the bottom of the Petri dish has been inverted over the lid containing the ammonium hydroxide aspositive result in （P5CO4） and （P7CO4） observed. Essentially no color change occurs on the undersides of colonies that are not producing aflatoxinsthis indicate to the negative results （control）. The main objective of this study is to isolation, identification and rapid detection of aflatoxin from wheat seed borne fungi.

Immobilization of Starch Phosphorylase from Germinating Wheat Seeds

Starch phosphorylase is an industrially important enzyme used in the production of glucose-l-phosphate. Here, we extracted the enzyme from the germinating wheat seeds and partially purified using ammonium sulfate fractionation. The partially purified enzyme showed maximum enzyme activity at pH 6.2 and pH 7.2 in the polysaccharide and glucose-l-phosphate formation directions, respectively. The enzyme showed maximum enzyme activity at 37 ℃ temperature with 50% of the enzyme activity at 32 ℃ and 42 ℃. The desalted ammonium sulfate fractionated enzyme has been immobilized on brick dust with nearly 60% enzyme activity retention. The specific activity of the immobilized starch phosphorylase increased from 0.410 to 0.925. There was a slight alkaline shift in the optimum pH when assayed in both the directions. The immobilized starch phosphorylase also displayed increased optimum temperature and thermo-stability and could be reused many times. The desalted ammonium sulfate fractionated enzyme exhibited a half life of 4 h at 30 ℃ and 30 rain at 50 ℃ whereas brick dust immobilized enzyme exhibited a half life of 7 h at 30 ℃ and 45 min at 50 ℃. The immobilized enzyme may be exploited for glucose-l-phosphate production.

Activity test and mechanism study of an environmentally friendly wheat seed coating agent

This novel environmentally friendly wheat seed coating agent which has been made with natural polymer as the primary material could increase yield by about 9% compared with the conventionally virulent wheat seed coating agent. In the premise of this production, the content of malondialdehyde (MDA) and peroxidase (POD) was determined. The results show that, after treated by the self-made wheat seed coating agent, the contents of the MDA were less than traditional group and the blank control group and POD contents were higher than traditional group and blank control group, this provides a good foundation on the further research of self-control wheat seed coating agent.

Fungi associated with wheat seed discolouration and abnormalities in <i>in-vitro</i>study

The main aim of present study is to ascertain the fungal species and their effect on germination associated with wheat seeds. Seeds of three varieties WH896, PBW-373 and HD264 of wheat (Triticum aestivum) were collected from Quarsi Agriculture Farm Aligarh. These three seed samples of wheat showing different forms of discouloration and abnormalities were screened for associated fungi. Microscopic examination of wheat seeds reveals that seeds of all the varieties of wheat possess injuries to varying extent. Detailed examination of the seeds has shown that the seeds can be classified on the basis of extent of injury in the three categories viz., seeds having minor cracks, cracks without exposed embryo and cracks with exposed embryo. Seed soaking and washing techniques were also employed. Fusarium moniliforme and Alternaria alternata were isolated from all the categories of seed tested. Floating mycelial bits and conidia of Alternaria, Fusarium, Drechslera, Curvularia lunata, Mucor were found in all the three varieties of wheat. The seeds were subjected to visual observation and examination under stereoscopic microscope. These findings are to study and detect the phytopathogenic mycoflora which causes damage and loss to our seeds and crops.

Effects of Different Row Ratios of Male and Female Parents and Application Amount of Nitrogen Fertilizer on Hybrid Wheat Seed Production and Its Component Factors

In order to screen suitable high hybrid wheat seed production technology,the split-plot experiment design was adopted and study was carried out about the effects of the different row ratios of male and female parents and application amount of nitrogen fertilizer on hybrid wheat seed production and its component factors. The results showed that the seed production increased with the increase in the number of female parent row. When the row ratio of male and female parents was 2 ∶ 6,the seed production was 3 683. 8 kg/ha; when the application amount of nitrogen fertilization was 50 kg/ha,the seed production was 3 649. 4 kg/ha; the interaction between the row ratio of male and female parents and the application amount of nitrogen fertilizer indicated that when the row ratio of male and female parents was 2∶ 6 and the application amount of nitrogen fertilizer was 300 kg/ha,the seed production reached the highest( 4160. 6 kg/ha). The row ratio of male and female parents and application amount of nitrogen fertilizer had significant effect on the component factors of seed production,including the number of grains per spike,spike weight and setting percentage. When the row ratio of male and female parents was 2∶ 5,the number of grains per spike,spike weight and setting percentage were the highest at 26. 7 grains,1. 12 g,and 62. 6% respectively; when application amount of nitrogen fertilizer was 450 kg/ha,the number of grains per spike,spike weight and setting percentage were the highest at 26. 0 grains,1. 08 g,and59. 2% respectively; the interaction of row ratio of male and female parents and application amount of nitrogen fertilizer had significant effect on the number of grains per spike,spike weight and setting percentage; when the row ratio of male and female parents was 2∶ 5 and the application amount of nitrogen fertilizer was 300 kg/ha,the number of grains per spike,spike weight and setting percentage were the highest at 29. 6grains,1. 24 g,and 71. 6% respectively. The number of grains per spike is the largest component factor for seed production. Increasing the number of grains per spike can increase the seed production. According to the effects of row ratio of male and female parents and application amount of nitrogen fertilizer on the component factors of seed production,the optimal condition was 2∶ 5-2∶ 6 for row ratio of male and female parents and 300-450 kg/ha for application amount of nitrogen fertilizer.

Differentiation of storage time of wheat seed based on near infrared hyperspectral imaging

Seed aging during storage is one of the main factors that influence the quality of wheat seed.Current detection methods based on NIR spectra were mostly for group seeds,they had poor stability for single seed detection because of sample uniformity.In this study,the characteristic changes of single wheat seed during storage procedure were measured through hyperspectral imaging technology.Firstly,hyperspectral imaging data of wheat grain including six years from 2007 to 2012 had been collected.The original spectra showed clear difference in the band of 1400-1600 nm,which may be caused by the decreasing of moisture and protein content during storage;principal component analysis(PCA)was applied to analyze the spectral data of wheat grain including six years,the clustering chart of the principal components indicated that the grain between same or similar year have an clustering characteristic,and the characteristic difference would become obviously with the increasing of storage time;soft independent modeling of class analogy(SIMCA)was applied to classify the grain of different years,results showed that the classification accuracy of the dichotomy between adjacent years could reach 97.05%,and the accuracy of the mixed classification of six years could also reach 82.5%.These results indicated that hyperspectral imaging technology could be used to differentiate the quality change of wheat seed during different storage time,which could provide support for the intelligent monitoring of stored wheat seeds.

Negative Association between Seed Dormancy and Seed Longevity in Bread Wheat

Many organisms have dormant stages with an extension of their life span to increase longevity, and deeper dormancy is usually related to greater longevity. In cereal crops, seed dormancy is significantly associated with pre-harvest sprouting tolerance during seed development, as seed longevity is a valuable trait for seed banks and providing reliable crop seeds to farmers. In this study, we evaluated both seed dormancy and longevity in bread wheat based on germination and artificial aging tests. According to phenotypic clustering analysis, relative germination rate/potential and relative seedling vigor index were more effective to indicate seed longevity than relative electrical conductivity in wheat, while all the four investigated phenotypes of relative germination potential, relative germination rate, germination index and degree of seed dormancy fit well as a reflex of wheat seed dormancy. In the correlation analysis, the germination level of newly harvested grain negatively reflected its degree of seed dormancy, while the germination ability of grain after artificial aging reflected its seed longevity. However, in contrast to the current opinion in plant, seed dormancy was significantly negatively correlated to seed longevity in our study, and it was not an accidental phenomenon, for that the majority of accessions with high degree of seed dormancy had short seed longevity. To our knowledge, this is the first to report the negative association between seed dormancy and longevity in cereal crops. It would lead to further concerns about how to breed wheat with both prolonged seed longevity and deep dormancy to avoid pre-harvest sprouting.

Applying acoustic emission and neural network to classify wheat seeds from weed seeds

In the present study,an expert weed seeds recognition system combining acoustic emissions analysis,Multilayer Feedforward Neural Network(MFNN)classifier was developed and tested for classifying wheat seeds.This experiment was performed for classifying two major important wheat varieties from five species of weed seeds.In order to produce sound signals,a 60o inclined glass plate was used.Fast Fourier Transform(FFT),Phase and Power Spectral Density(PSD)of impact signals were calculated.All features of sound signals are computed via a 1024-point FFT.After feature generation,60%of data sets were used for training,20%for validation,and remaining samples were selected for testing.The optimized MFNN model was found to have 500-12-2 and 500-10-2 architectures for“101”and“Shiroodi”wheat varieties,respectively.The selection of the optimal model was based on the evaluation of mean square error(MSE)and correct separation rate(CSR).The CSR percentages for two wheat varieties were 100%.Considering the overall aspects of the results,it can be stated that the developed system was successful enough to correlate the acoustic features with wheat seed type.

Effect of Cold Plasma Treatment on Seed Germination and Growth of Wheat

This study investigated the effect of cold helium plasma treatment on seed germina- tion, growth and yield of wheat. The effects of different power of cold plasma on the germination of treated wheat seeds were studied. We found that the treatment of 80 W could significantly improve seed germination potential （6.0%） and germination rate （6.7%） compared to the control group. Field experiments were carried out for wheat seeds treated with 80 W cold plasma. Com- pared with the control, plant height （20.3%）, root length （9.0%） and fresh weight （21.8%） were improved significantly at seedling stage. At booting stage, plant height, root length, fresh weight, stem diameter, leaf area and leaf thickness of the treated plant were respectively increased by 21.8%, 11.0%, 7.0%, 9.0%, 13.0% and 25.5%. At the same time, the chlorophyll content （9.8%）, nitrogen （10.0%） and moisture content （10.0%） were higher than those of the control, indicating that cold plasma treatment could promote the growth of wheat. The yield of treated wheat was 7.55 t-ha-1, 5.89% more than that of the control. Therefore, our results show that cold plasma has important application prospects for increasing wheat yield.

Hydrogen Sulfide Promotes Wheat Seed Germination and Alleviates Oxidative Damage against Copper Stress

With the enhancement of copper （Cu） stress, the germination percentage of wheat seeds decreased gradually. Pretreatment with sodium hydrosulfide （NariS）, hydrogen sulfide （H2S） donor alleviated the inhibitory effect of Cu stress in a dose- dependent manner; whereas little visible symptom was observed in germinating seeds and radicle tips cultured in NariS solutions. It was verified that H2S or HS- rather than other sulfur-containing components derived from NariS attribute to the potential role in promoting seed germination against Cu stress. Further studies showed that NariS could promote amylase and esterase activities, reduce Cu-induced disturbance of plasma membrane integrity in the radicle tips, and sustain lower levels of malondialdehyde and H202 in germinating seeds. Furthermore, NariS pretreatment increased activities of superoxide dismutase and catalase and decreased that of lipoxygenase, but showed no significant effect on ascorbate peroxidase. Alternatively, NariS prevented uptake of Cu and promoted the accumulation of free amino acids in seeds exposed to Cu. In addition, a rapid accumulation of endogenous H2S in seeds was observed at the early stage of germination, and higher level of H2S in NaHS-pretreated seeds. These data indicated that H2S was involved in the mechanism of germinating seeds＇ responses to Cu stress.

Effect of polyamine on seed germination of wheat under drought stress is related to changes in hormones and carbohydrates

Drought is a multifaceted stress condition that inhibits crop growth. Seed germination is one of the critical and sensitive stages of plants, and its process is inhibited or even entirely prevented by drought. Polyamines （PAs） are closely associ- ated with plant resistance to drought stress and seed germination. However, little is known about the effect of PA on the seed germination of wheat under drought stress. This study investigated the involvement of PAs in regulating wheat seed germination under drought stress. Six wheat genotypes differing in drought resistance were used, and endogenous PA levels were measured during seed germination under different water treatments. In addition, external PAwas used for seed soaking and the variation of hormones, total soluble sugar and starch were measured during the seed germination under different water treatments. These results indicated that the free spermidine （Spd） accumulation in seeds during the seed germination period favored wheat seed germination under drought stress; however, the free putrescine （Put） accumulation in seeds during the seed germination period may work against wheat seed germination under drought stress. In addition, seed soaking in Spd and spermine （Spm） significantly relieved the inhibition of seed germination by drought stress; howev- er, soaking seeds in Put had no significant effect on seed germination under drought. External Spd and Spm significantly increased the endogenous indole-3-acetic acid （IAA）, zeatin （Z）＋zeatin riboside （ZR）, abscisic acid （ABA）, and gibberellins （GA） contents in seeds and accelerated the seed starch degradation and increased the concentration of soluble sugars in seeds during seed germination. This may promote wheat seed germination under drought stress. In conclusion, free Spd and Put are key factors for regulating wheat seed germination under drought stress and the effects of Spd and Put on seed germination under drought notably related to hormones and starch metabolism.

Differential Gene Expression Between Cross-Fertilized and Self-Fertilized Kernels During the Early Stages of Seed Development in Wheat

In order to understand molecular basis of cross-fertilized kernel advantage and heterosis, improved differential display of mRNA was used in this study to analyze alterations in gene expression between cross-fertilized and self-fertilized kernels at 2, 4, 6, 8, 10 and 12 days after pollination (DAP) by using 3 wheat hybrids with different level of heterosis. Four patterns of differential expression were observed: (i) bands observed in cross-fertilized kernels but not in self-fertilized kernels (BCnS); (ii) bands occurring in only self-fertilized kernels but not in cross-fertilized kernels (BSnC); (iii) cDNA over-expressed in cross-fertilized kernels compared to self-fertilized kernels (OEC); (iv) cDNA under-expressed in cross-fertilized kernels compared to self-fertilized kernels (UEC). Further analysis showed that BCnS is positively correlated with heterosis, but BSnC is negatively correlated with heterosis. Four differentially expressed cDNA fragments were verified by reverse-northern blot and sequence homology search in GenBank showed that one of them was new sequences; the other exhibited higher similarity to NBS-LRR type resistance protein, 1,6-bisphosphatase and photosystem Ⅱ chlorophyll a-binding protein psbB, respectively, which indicated diverse pathways may be involved in heterosis formation.

Contents and distribution of rare earth elements in wheat seeds

Contents of 15 rare earth elements (REEs) in the seeds of 60 breeds of wheat have been analyzed by the inductively-coupled plasma mass spectrometry (ICP-MS). The distribution pattern of contents of REEs in wheat seeds has been observed and compared with that in soils. Comparison with literature data has also been made. The results show that the background of REEs in wheat seeds is 10 11-108 g -g-1, 3-4 levels lower than in soils. The distribution pattern is light REEs higher in contents and slight Eu-anomaly, similar to that in soils. The data obtained in this study can accurately represent the background content of REEs in wheat seeds.

Biological effects of implantation and penetration of nitrogenion beams on wheat seeds

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The Level of Expression of Thioredoxin is Linked to Fundamental Properties and Applications of Wheat Seeds

Work with cereals （barley and wheat） and a legume （Medicago truncatula） has established thioredoxin h （Trx h） as a central regulatory protein of seeds. Trx h acts by reducing disulfide （S-S） groups of diverse seed proteins （storage proteins, enzymes, and enzyme inhibitors）, thereby facilitating germination. Early in vitro protein studies were complemented with experiments in which barley seeds with Trx h overexpressed in the endosperm showed accelerated germination and early or enhanced expression of associated enzymes （α-amylase and pullulanase）. The current study extends the transgenic work to wheat. Two approaches were followed to alter the expression of Trx h genes in the endosperm： （1） a hordein promoter and its protein body targeting sequence led to overexpression of Trx hS, and （2） an antisense construct of Trx h9 resulted in cytosolic underexpression of that gene （Arabidopsis designation）. Underexpression of Trx h9 led to effects opposite to those observed for overexpression Trx h5 in barley--retardation of germination and delayed or reduced expression of associated enzymes. Similar enzyme changes were observed in developing seeds. The wheat lines with underexpressed Trx showed delayed preharvest sprouting when grown in the greenhouse or field without a decrease in final yield. Wheat with overexpressed Trx h5 showed changes commensurate with earlier in vitro work： increased solubility of disulfide proteins and lower aUergenicity of the gliadin fraction. The results are further evidence that the level of Trx h in cereal endosperm determines fundamental properties as well as potential applications of the seed.