The P-type plasma membrane(PM)H^(+)-ATPases(HAs)are crucial for plant development,growth,and defense.The HAs have been thoroughly characterized in many different plants.However,despite their importance,the functions o...The P-type plasma membrane(PM)H^(+)-ATPases(HAs)are crucial for plant development,growth,and defense.The HAs have been thoroughly characterized in many different plants.However,despite their importance,the functions of HAs in germination and seed dormancy(SD)have not been validated in wheat.Here,we identified 28 TaHA genes(TaHA1-28)in common wheat,which were divided into five subfamilies.An examination of gene expression in strong-and weak-SD wheat varieties led to the discovery of six candidate genes(TaHA7/-12/-14/-16/-18/-20).Based on a single nucleotide polymorphism(SNP)mutation(C/T)in the TaHA7 coding region,a CAPS marker(HA7)was developed and validated in 168 wheat varieties and 171 Chinese mini-core collections that exhibit diverse germination and SD phenotypes.We further verified the roles of the two allelic variations of TaHA7 in germination and SD using wheat mutants mutagenized with ethyl methane sulphonate(EMS)in‘Jimai 22’and‘Jing 411’backgrounds,and in transgenic Arabidopsis lines.TaHA7 appears to regulate germination and SD by mediating gibberellic acid(GA)and abscisic acid(ABA)signaling,metabolism,and biosynthesis.The results presented here will enable future research regarding the TaHAs in wheat.展开更多
Seeds of many woody plant species have one of several types of dormancy. They do not germinate unless ,specific environmental signals are in place or events occur. This study was conducted to evaluate the effects of s...Seeds of many woody plant species have one of several types of dormancy. They do not germinate unless ,specific environmental signals are in place or events occur. This study was conducted to evaluate the effects of scarification treatments on seed dormancy and germination of Acacia nilotica (L.) Willd. ex Del., Prosopis juliflora (Sw.) DC. :and Dodonaea viscosa (L.) Jacq. The following treatments were applied: T1, untreated seed (control); T2, sulphuric acid (97%) for 45 min; T3, boiling water for 5 min. The seeds were cultured on a Murashige and Skoog (MS) medium after sterilization. The responses of seeds to treatments were compared with each other and with the control treatment. Germination was observed daily for a 30-day period. Results indicated positive responses to treatments, while impermeable Seed coats may be responsible for low germination rates in intact seeds as seen experimentally in the untreated control. The highest germination was obtained for P. juliflora and D. viscosa acid-scarified seeds (80.8%-90.8%) and for scarified seeds of A. nilotica (50.2%) boiled in water. The germination indices, i.e., final germination percentage (FG), mean daily germination (MDG) and germination rate (GR), were significantly affected by treatments and species (p 〈 0.01).展开更多
During germination of barley(Hordeum vulgare L.) seeds, important morphological and physiological changes take place, including development of organs and tissues and activation of metabolic pathways. Germination and d...During germination of barley(Hordeum vulgare L.) seeds, important morphological and physiological changes take place, including development of organs and tissues and activation of metabolic pathways. Germination and dormancy of seeds are regulated by abscisic acid, gibberellins, reactive oxygen species(ROS), reactive nitrogen species(RNS)and several other factors. Activities of ascorbate-glutathione cycle enzymes, responsible for scavenging ROS, strongly increase. Catalase and superoxide dismutase activities, also scavenging ROS, decrease at the onset of seed germination and then increase. With the increase in aerobic metabolism after radicle protrusion, the activities of the fermentation enzymes lactate and alcohol dehydrogenase decline rapidly. The RNS-scavenging activity of S-nitrosoglutathione reductase decreases in the course of seed germination, in concert with elevation of nitric oxide production and protein nitrosylation. This activity supports the role of RNS in regulating seed germination. Transcription of various genes at different phases of seed germination exhibits phase-specific changes. During imbibition, genes involved in cell wall metabolism are highly expressed; in the middle phase of seed germination before radicle protrusion, genes involved in amino acid synthesis, protein synthesis, and transport and nucleic acid synthesis are upregulated significantly, and after radicle protrusion, genes involved in photosynthetic metabolism are induced. In summary, signal transduction and metabolic regulation of seed germination involve diverse reactions and complex regulation at different levels of metabolic organization.展开更多
Seed dormancy and germination characteristics are important factors determining plant reproductive success, and may be expected to have a major influence on plant distribution. In this study, we aimed to explore the c...Seed dormancy and germination characteristics are important factors determining plant reproductive success, and may be expected to have a major influence on plant distribution. In this study, we aimed to explore the characteristics of seed dormancy and germination in two endemic Rheum species(Rheum nobile and Rheum alexandrae) in the Himalaya-Hengduan Mountains. To determine the type of dormancy,fresh seeds of the two species(one population each) were incubated in light at 25/15 and 15/5℃, and then dry after-ripening(DAR) seeds were incubated on water agar substrate with or without GA_3. To determine the effect of temperature and light on germination, DAR seeds of the two species(two populations each) were incubated both in the light and in the dark at several temperatures, including constant and alternating temperatures. Base temperature(T_b) and thermal times for 50% germination(θ_(50)) were calculated. DAR released physiological dormancy(PD), increasing final germination at 15/5℃ and widening the range of germination temperatures from higher to lower, indicative of type 2 non-deep PD for the two Rheum species. Light had no significant effect on germination of seeds from the two species(two populations each). Seeds of the two species germinated significantly better(>80%) at medium temperatures(10-25℃) than at extreme low(5℃) or high(35℃) temperatures. Alternating temperatures(25/15 and 15/5℃) did not significantly increase the final germination of the two species either in the light and in the dark, but it promoted seed germination more quickly than corresponding constant temperatures in the light in both Rh. alexandrae populations, especially at 15/5℃. Germination in response to temperature was well described by the thermal-time model at suboptimal temperatures. The estimated Tbvalues were 1 and 0.9℃, respectively, in two Rh. nobile populations; 4 and 4.1℃,respectively, in two Rh. alexandrae populations; θ_(50)(thermal time) were 100 and 125℃d, respectively in two Rh. nobile populations; 76.92 and 83.33℃d, respectively in two Rh. alexandrae populations. The dormancy type, and germination responses to temperature and light condition does not explain why the two Rheum species are distributed in contrasting habitats. However, these findings reflect an advantageous germination strategy of these two Rheum species to adapt to the same alpine environments.展开更多
For improving seed germination of Prosopis koelziana and Prosopis juliflora, different treatments of seeds were conducted, including scarification with sulfuric acid 98% for 10 and 15 min, sandy paper, hot water for 5...For improving seed germination of Prosopis koelziana and Prosopis juliflora, different treatments of seeds were conducted, including scarification with sulfuric acid 98% for 10 and 15 min, sandy paper, hot water for 5 and 10 min, potasium nitrate 0.1%, gibberellic acid at 250 mg·L^-1 and 500 mg·L^-1 and combinational treatment of scarification with gibberellic acid of 250 mg·L^-1 and 500 mg·L^-1. The results show that scarifications with sandy paper and sulfuric acids 98% were the most effective treatments on breaking seed dormancy and seed germination induction. Scarification with sulfuric acid 98% for 15 min was the best treatment. According to the positive effect of scarification and lack of reaction of seeds against KNO3 and gibberellic acid, the kind of seed dormancy was determined as exogenous.展开更多
Low-pressure discharge is applied for stimulation of germination of two seed lots of Lamb's Quarters (Chenopodium album agg.) with different starting germinations (17%, 8%) and in different stages of dormancy. Di...Low-pressure discharge is applied for stimulation of germination of two seed lots of Lamb's Quarters (Chenopodium album agg.) with different starting germinations (17%, 8%) and in different stages of dormancy. Different exposition durations with cold plasma treatment were applied. The variable of the ratio cumulative germination was calculated. The Richards' equation was used for curve-fitting and simulation of the growth curves. Population parameters, namely Vi - viability, Me - time, Qu - dispersion, and Sk - skewness, counted from the curves described the germination rate well. Significant differences among Qu confirmed the erratic dormancy and gradual germination of Lamb's Quarters. No difference in the Me parameter was found between two tested seed lots, and no interspecies characteristics were changed using low-pressure discharge. The results suggested that plasma treatment changed seed germination in Lamb's Quarters seeds.展开更多
To achieve a good production of a crop, it is essential to know the ability of the species to successfully complete two critical stages in the life cycle such as germination and seedling establishment. In this paper w...To achieve a good production of a crop, it is essential to know the ability of the species to successfully complete two critical stages in the life cycle such as germination and seedling establishment. In this paper we study in comparative form structure of the seed, the importance of tegument in dormancy, the effect of accelerated aging on seed germination and viability, and the early and late growth in J. curcas and J. macrocarpa. External morphology of the seeds allow difference and internally also the embryos show evident differences. J. macrocarpa germination is around 0% - 4%. The total removal of tegument showed a 50% increase and the other treatments between 0% - 10%. Aging accelerated by Tetrazolium test allowed a comparative analysis of VP and GP. J. curcas maintains both to 96 h, while J. macrocarpa the seed viability is registered along the all treatment. J. macrocarpa seeds have less synchronicity than those of J. curcas. ABA and JAs were detected in tegument of J. macrocarpa and J. curcas seeds. JA could have a roll in inhibition of germination of J. macrocarpa seeds. Early and late growth, FW and DW of root, hypocotyl, epicotyl and leaf of J. curcas were significantly different in both species.展开更多
Magnolia sinica is one of the most endangered Magnoliaceae species in China.Seed biology information concerning its long-term ex situ conservation and utilization is insufficient.This study investigated dormancy statu...Magnolia sinica is one of the most endangered Magnoliaceae species in China.Seed biology information concerning its long-term ex situ conservation and utilization is insufficient.This study investigated dormancy status,germination requirements and storage behavior of M.sinica.Freshly matured seeds germinated to ca.86.5%at 25/15℃but poorly at 30℃;GA3 and moist chilling promoted germination significantly at 20℃.Embryos grew at temperatures(alternating or constant)between 20℃and 25℃,but not at 5℃or 30℃.Our results indicate that M.sinica seeds possibly have non-deep simple mor-phophysiological dormancy(MPD).Seeds survived desiccation to 9.27%and 4.85%moisture content(MC)as well as a further 6-month storage at-20℃and in liquid nitrogen,including recovery in vitro as excised embryos.The established protocol ensured that at least 58%of seedlings were obtained after both cold storage and cryopreservation.These results indicate that both conventional seed banking and cryopreservation have potential as long-term ex situ conservation methods,although further optimized approaches are recommended for this critically endangered magnolia species.展开更多
Elucidating the regulatory mechanisms of environmental factors on seed dormancy and germination will provide guidance for tree regeneration.Toward understanding the coupled effect of light and temperature on dormancy ...Elucidating the regulatory mechanisms of environmental factors on seed dormancy and germination will provide guidance for tree regeneration.Toward understanding the coupled effect of light and temperature on dormancy release and germination of Pinus koraiensis seeds,we set up three light conditions(L200:200μmol m^(-2) s^(-1),L20:20μmol m^(-2) s^(-1),L0:0μm^(-2) s^(-1))and four storage temperatures[T-5:-5°C(50 days),T5:-5°C(50 days)+5°C(50 days),T25:-5°C(50 days)+5°C(50 days)+25°C(50 days),T15:-5°C(50 days)+5°C(50 days)+25°C(50 days)+15°C(50 days)]using imbibed seeds,then quantified phytohormones gibberellic acid(GA_(3))and abscisic acid(ABA)during the stratification.Germination percentage(G_(P)),mean germination time(T_(M)),and germination value(G_(V))under 25/15°C temperature and the three light conditions were then determined.Phytohormone levels and germination performances were significantly affected by light and temperature.No consistent trend was found between the phytohormone levels and G_(P) caused by light levels.Under the three light conditions,ABA concentrations in the embryo and endosperm decreased as storage temperature shifted from T-5 to T25 and increased from T25 to T15;GA_(3) decreased in nearly all four storage temperatures.G_(P) reached 40–60%in T25 storage without light irradiance.In the three light conditions,G_(P) and G_(V) were higher at T5 and T25 than at T-5 and T15;so T5 and T25 are considered as optimum storage temperatures for dormancy release and germination.At optimum temperatures,light(L200,L20)significantly increased the G_(P) and G_(V) compared with the dark(L0).At L200 and L20,significant negative correlations between G_(V) and the ABA concentrations and positive correlations between G_(V) and GA/ABA in the seed embryo were found.Temperature played a more important role in primary dormancy release and germination;light was unnecessary for primary dormancy release.Light facilitated seed germination at optimum temperatures.The dormancy release and germination of P.koraiensis seeds were controlled by a decrease in ABA concentrations or an increase in GA/ABA induced by temperature variations.展开更多
To improve understanding of Portulaca pilosa seed germination and lay technical foundation for seedling cultivation,this paper studies the characteristics of dormancy and germination of Portulaca pilosa seed. Research...To improve understanding of Portulaca pilosa seed germination and lay technical foundation for seedling cultivation,this paper studies the characteristics of dormancy and germination of Portulaca pilosa seed. Research indicates that its primary seed dormancy period is about25 d,dormancy can be completely released by storage at room temperature for 30 d; the seed is positively photoblastic seed that can't sprout and can be induced into dormancy in low light conditions; the dormancy-released seed is more sensitive to light when compared with the freshly picked seed,and the germination peak arises 1 d earlier; Portulaca pilosa seed favorites humid conditions,and the higher the soil moisture,the higher the germination rate and germination energy of the seed. The dormancy-released seeds should be used for Portulaca pilosa seedling cultivation,and after the germination is accelerated for 2- 3 d in the light conditions,the seeds are sown on the soil surface,and covered with transparent plastic film to keep moisture and light,which is conducive to the emergence of seeds.展开更多
Several Chinese Iris species have potential for medicinal and ornamental use, but they have poor, erratic or slow seed germination. The aims of this study was to classify Iris ehrysographes dormancy type and investiga...Several Chinese Iris species have potential for medicinal and ornamental use, but they have poor, erratic or slow seed germination. The aims of this study was to classify Iris ehrysographes dormancy type and investigate the optimum treatment for seeds germination through examining the effects of various incubation temperatures, light conditions, scarification, stratification and soil substratum. Seed viability of/. chrysographes was 74% and seeds imbibed water very fast. No seeds germinated on stratification, soil substratum, constant or alternating temperatures, light and darkness treatments. Seeds germination of different mechanical restriction treatments had significant differences. The results indicated that: (1) removal of seed coat was the most effective treatment for/. chrysographes germination; (2) physiological dormancy phenomenon was found in this species.展开更多
The germination process of seeds is influenced by the interplay between two opposing factors,pectin methylesterase(PME)and pectin methylesterase inhibitor(PMEI),which collectively regulate patterns of pectin methylest...The germination process of seeds is influenced by the interplay between two opposing factors,pectin methylesterase(PME)and pectin methylesterase inhibitor(PMEI),which collectively regulate patterns of pectin methylesterification.Despite the recognized importance of pectin methylesterification in seed germination,the specific mechanisms that govern this process remain unclear.In this study,we demonstrated that the overexpression of GhPMEI53is associated with a decrease in PME activity and an increase in pectin methylesterification.This leads to seed cell wall softening,which positively regulates cotton seed germination.AtPMEI19,the homologue in Arabidopsis thaliana,plays a similar role in seed germination to GhPMEI53,indicating a conserved function and mechanism of PMEI in seed germination regulation.Further studies revealed that GhPMEI53 and AtPMEI19 directly contribute to promoting radicle protrusion and seed germination by inducing cell wall softening and reducing mechanical strength.Additionally,the pathways of abscicic acid(ABA)and gibberellin(GA)in the transgenic materials showed significant changes,suggesting that GhPMEI53/AtPMEI19-mediated pectin methylesterification serves as a regulatory signal for the related phytohormones involved in seed germination.In summary,GhPMEI53 and its homologs alter the mechanical properties of cell walls,which influence the mechanical resistance of the endosperm or testa.Moreover,they impact cellular phytohormone pathways(e.g.,ABA and GA)to regulate seed germination.These findings enhance our understanding of pectin methylesterification in cellular morphological dynamics and signaling transduction,and contribute to a more comprehensive understanding of the PME/PMEI gene superfamily in plants.展开更多
Salinity is one of the most significant risks to crop production and food security as it harms plant physiology and biochemistry.The salt stress during the rice emergence stages severely hampers the seed germination a...Salinity is one of the most significant risks to crop production and food security as it harms plant physiology and biochemistry.The salt stress during the rice emergence stages severely hampers the seed germination and seedling growth of direct-seeded rice.Recently,nanoparticles(NPs)have been reported to be effectively involved in many plant physiological processes,particularly under abiotic stresses.To our knowledge,no comparative studies have been performed to study the efficiency of conventional,chemical,and seed nanopriming for better plant stress tolerance.Therefore,we conducted growth chamber and field experiments with different salinity levels(0,1.5,and 3‰),two rice varieties(CY1000 and LLY506),and different priming techniques such as hydropriming,chemical priming(ascorbic acid,salicylic acid,and γ-aminobutyric acid),and nanopriming(zinc oxide nanoparticles).Salt stress inhibited rice seed germination,germination index,vigor index,and seedling growth.Also,salt stress increased the over accumulation of reactive oxygen species(H_(2)O_(2) and O_(2)^(-)·)and malondialdehyde(MDA)contents.Furthermore,salt-stressed seedlings accumulated higher sodium(Na^(+))ions and significantly lower potassium(K^(+))ions.Moreover,the findings of our study demonstrated that,among the different priming techniques,seed nanopriming with zinc oxide nanoparticles(NanoZnO)significantly contributed to rice salt tolerance.ZnO nanopriming improved rice seed germination and seedling growth in the pot and field experiments under salt stress.The possible mechanism behind ZnO nanopriming improved rice salt tolerance included higher contents of α-amylase,soluble sugar,and soluble protein and higher activities of antioxidant enzymes to sustain better seed germination and seedling growth.Moreover,another mechanism of ZnO nanopriming induced rice salt tolerance was associated with better maintenance of(K^(+))ions content.Our research concluded that NanoZnO could promote plant salt tolerance and be adopted as a practical nanopriming technique,promoting global crop production in saltaffected agricultural lands.展开更多
Low temperatures during germination inhibit seed growth,lead to small and weak seedlings,and significantly reduce the wheat yield.Alleviating the adverse effects of low temperature on wheat seed germination is highly ...Low temperatures during germination inhibit seed growth,lead to small and weak seedlings,and significantly reduce the wheat yield.Alleviating the adverse effects of low temperature on wheat seed germination is highly important for achieving high and stable wheat yields.In this study,Tongmai 6(insensitive)and Zhengmai 113(sensitive),which have different low-temperature sensitivities during germination were treated with low temperature during germination.The transcriptome,metabolome and physiological data revealed that low temperature decreased the germination rate,downregulated the expression of a large number of genes involved in regulating glycometabolism,and inhibited carbon,nitrogen(especially amino acids)and energy metabolism in the seeds.Arginine content increased at low temperature,and its increase in the low-temperature-tolerant variety was significantly greater than that in the sensitive variety.Arginine priming experiment showed that treatment with an appropriate concentration of arginine improved the seed germination rate.The conversion of starch to soluble sugar significantly increased under exogenous arginine conditions,the content of key metabolites in energy metabolism increased,and the utilization of ATP in the seeds increased.Taken together,arginine priming increased seed germination at low temperature by relieving inhibition of seed carbon and nitrogen metabolism and improving seed energy metabolism.展开更多
Seed germination is a complex trait regulated by multiple genes in rice.However,the regulators of rice seed germination have yet to be sufficiently determined.Here,a quantitative trait locus(QTL)for rice seed germinat...Seed germination is a complex trait regulated by multiple genes in rice.However,the regulators of rice seed germination have yet to be sufficiently determined.Here,a quantitative trait locus(QTL)for rice seed germination was identified in a genome-wide association study.The candidate gene JASMONATE ZIM-DOMAIN 5(OsJAZ5)of the QTL was verified that positively regulates seed germination.OsJAZ5 regulation of seed germination involves an OsABI3-mediated abscisic acid pathway.Overexpression of OsJAZ5 facilitated seed germination.The application of OsJAZ5 might be useful for increasing seed germination for rice direct seeding.展开更多
To mitigate the wastage of seed resources and reduce the usage of pesticides and fertilizers, seed coating agentshave gained popularity. This study employs single-factor and multi-index orthogonal experimental design ...To mitigate the wastage of seed resources and reduce the usage of pesticides and fertilizers, seed coating agentshave gained popularity. This study employs single-factor and multi-index orthogonal experimental design methodsto investigate the seed coating formula and physical properties of Tartary buckwheat. The specific effects ofeach component on Tartary buckwheat seed germination are analyzed. The findings reveal that the seed coatingagent formulated with 1.5% polyvinyl alcohol, 0.15% sodium alginate, 0.2% op-10, 0.1% polyacrylamide, 8% colorant,3% ammonium sulfate, 1% potassium dihydrogen phosphate, and 0.15% carbendazim exhibits the mosteffective coating. It demonstrates optimal physical properties and promotes seed germination efficiently. The suspensionrate of this seed coating agent reaches 91.12%, with a mere 2.13% coating shedding rate and 2.5% coatingseed rot rate. Furthermore, it achieves a germination percentage of 99.17%, which is 20.84% higher than the lowestgroup. The germination potential and index are also significantly higher than the lowest group, with anincrease of 20.84% and 26.56%, respectively. Additionally, the vitality index is 553.08, a 15.75% increase comparedto the lowest group. The application of seed coating agents helps reduce seed resource loss, increase plant numbers,and ultimately enhance agricultural yields. This finding holds practical significance in agriculturalproduction.展开更多
Amaranthus retroflexus L. is a serious and widespread malignant weed in soybean fields in Heilongjiang Province. Exploring the dormancy characteristics of A. retroflexus L. seeds and the physiological response of its ...Amaranthus retroflexus L. is a serious and widespread malignant weed in soybean fields in Heilongjiang Province. Exploring the dormancy characteristics of A. retroflexus L. seeds and the physiological response of its seedlings to acifluorfen sodium can provide a basis for further researches on its resistance mechanism. Using newly harvested and stored A. retroflexus L. seeds for one year as experimental materials, the effects of different concentrations of HCl, NaOH, water temperature, gibberellic acid(GA) and polyethylene glycol(PEG) on the dormancy and germination of A. retroflexus L. seeds were studied. The sensitivity of A. retroflexus L.to acifluorfen sodium was determined using bioassay. The effects on leaf chlorophyll content and target enzyme activity were studied at a normal dosage of 360 g a.i. hm^(-2) and a doubling dosage of 720 g a.i. hm^(-2) of acifluorfen sodium. Newly harvested seeds exhibiting dormancy were soaked in water of various temperatures and in different concentrations of NaOH and HCl, which were ineffective in breaking the seed dormancy. GA could break seed dormancy, and the highest seed germination rate reached 93.33% when they were soaked at 3 000 mg·L^(-1) for 72 h and 4 000 mg·L^(-1) for 48 h. The drought stress was simulated with a 15%-25% polyethylene glycol solution, which had no significant effect on the seed germination rate. The GR_(50) value of acifluorfen sodium for A. retroflexus L. was 705.7 g a.i. hm^(-2), which was 1.96 times the recommended dose in the field. After the application of different doses of acifluorfen sodium, the chlorophyll content of A. retroflexus L. reached its minimum value 3 days after treatment(DAT), and then gradually increased. The activity of the target enzyme protoporphyrinogen oxidase(PPO) reached the highest value at 7 DAT under different dosages, and gradually returned to normal levels thereafter. Soaking with gibberellin was an effective method to break seed dormancy. A. retroflexus L. seeds had certain drought resistance during the germination process. A. retroflexus L. was not sensitive to acifluorfen sodium and acifluorfen sodium ether, and could not effectively inhibit the PPO activity, indicating that A. retroflexus L. had target resistance to acifluorfen sodium.展开更多
[Objective] The aim of this study was to provide the theoretical basis for screening and utilizing salt-tolerant tomato varieties as well as for cultivating salt-resistance.[Method] Salinity tolerance of tomato during...[Objective] The aim of this study was to provide the theoretical basis for screening and utilizing salt-tolerant tomato varieties as well as for cultivating salt-resistance.[Method] Salinity tolerance of tomato during seed germination under simple salt sodium chloride and double salt calcium nitrate or sodium chloride stress were studied by Petri dish culturing.[Result] As the two kinds salt concentration increased,the germination regularity,the germination rate,the germination index and the growing vigor index of tomato seedlings decreased,but the germination losing rate increased.When salt concentration was from 0.2% to 0.4%,there was little difference among all indexes under two kinds of salt stress.However,when salt concentration was from 0.6% to 1.0%,the difference among all indexes under two kinds of salt stress was significant.[Conclusion] Salinity tolerance of tomato seeds under double salt calcium nitrate or sodium chloride stress was higher than that under simple salt sodium chloride stress.展开更多
[ Objective ] The research aimed to reveal theeffects of excessive Mg^2+ on the germination characteristics of maize and soybean. [ Method ] Eleven concentration gradients of Mg^2+ including 0, 40, 80, 120, 160,200,...[ Objective ] The research aimed to reveal theeffects of excessive Mg^2+ on the germination characteristics of maize and soybean. [ Method ] Eleven concentration gradients of Mg^2+ including 0, 40, 80, 120, 160,200,240,280,320,360 and 400 mmol/L were set up to study the effects of different treatments on such indices as the germination potential, germination rate, fresh weight, dry weight, root length, plant height and stem diameter of maize and soybean. [ Result] With the increasing of Mg^2+ concentration, the germination of maize delayed and the germination rate of soybean obviously decreased, reaching the significant difference at 0.05 level. When Mg^2+ concentration increased, the fresh weight and dry weight of maize and soybean decreased, but maize and soybean showed some adaptability. The growth of radicles and seedlings in maize and soybean were obviously inhibited by Mg^2+ , and atrophy and dysplasia phenomena appeared. [ Conclusion] Excessive Mg^2+ stress has different effects on the germination potential and germination rate of different crops and has obvious poisoning effects on the root and stem growth of crops.展开更多
[ Objective] The study was to understand the changes of amylase(AMY) and superoxide dismutase(SOD) isozymes during the ger- mination process of Emmenopterys henryi Oliv seeds. [ Metbod] By employing polyacrylamide...[ Objective] The study was to understand the changes of amylase(AMY) and superoxide dismutase(SOD) isozymes during the ger- mination process of Emmenopterys henryi Oliv seeds. [ Metbod] By employing polyacrylamide gel electrophoresis method, the expressions of AMY and SOD isozymes during seed germination process were analyzed. ~ Result] The main AMY bands remained strong during the whole peri- od and a new band A2 appeared in the middle and late period of seed germination. Some new SOD bands occurred at the early stage, then be- came weak or disappeared in the middle period, and band S6 became intense in the late peried. [ Conclusion.] The expression of AMY and SOD isozyme gene has temporal difference during germination of E. henryi Oliv seeds.展开更多
基金supported by grants from the University Synergy Innovation Program of Anhui Province,China(GXXT-2021-058)the National Natural Science Foundation of China(U20A2033)+4 种基金the Natural Science Foundation of Anhui Province,China(2108085MC98)the Key Scientific and Technological Breakthroughs of Anhui Province,China(2021d06050003)the Anhui Province Education Department Sciences Research Project,China(YJS20210212)the Scientific Research Project of Higher Education in Anhui Province,China(2022AH050924 and 2022AH050885)the Jiangsu Collaborative Innovation Center for Modern Crop Production,China(JCIC-MCP)。
文摘The P-type plasma membrane(PM)H^(+)-ATPases(HAs)are crucial for plant development,growth,and defense.The HAs have been thoroughly characterized in many different plants.However,despite their importance,the functions of HAs in germination and seed dormancy(SD)have not been validated in wheat.Here,we identified 28 TaHA genes(TaHA1-28)in common wheat,which were divided into five subfamilies.An examination of gene expression in strong-and weak-SD wheat varieties led to the discovery of six candidate genes(TaHA7/-12/-14/-16/-18/-20).Based on a single nucleotide polymorphism(SNP)mutation(C/T)in the TaHA7 coding region,a CAPS marker(HA7)was developed and validated in 168 wheat varieties and 171 Chinese mini-core collections that exhibit diverse germination and SD phenotypes.We further verified the roles of the two allelic variations of TaHA7 in germination and SD using wheat mutants mutagenized with ethyl methane sulphonate(EMS)in‘Jimai 22’and‘Jing 411’backgrounds,and in transgenic Arabidopsis lines.TaHA7 appears to regulate germination and SD by mediating gibberellic acid(GA)and abscisic acid(ABA)signaling,metabolism,and biosynthesis.The results presented here will enable future research regarding the TaHAs in wheat.
文摘Seeds of many woody plant species have one of several types of dormancy. They do not germinate unless ,specific environmental signals are in place or events occur. This study was conducted to evaluate the effects of scarification treatments on seed dormancy and germination of Acacia nilotica (L.) Willd. ex Del., Prosopis juliflora (Sw.) DC. :and Dodonaea viscosa (L.) Jacq. The following treatments were applied: T1, untreated seed (control); T2, sulphuric acid (97%) for 45 min; T3, boiling water for 5 min. The seeds were cultured on a Murashige and Skoog (MS) medium after sterilization. The responses of seeds to treatments were compared with each other and with the control treatment. Germination was observed daily for a 30-day period. Results indicated positive responses to treatments, while impermeable Seed coats may be responsible for low germination rates in intact seeds as seen experimentally in the untreated control. The highest germination was obtained for P. juliflora and D. viscosa acid-scarified seeds (80.8%-90.8%) and for scarified seeds of A. nilotica (50.2%) boiled in water. The germination indices, i.e., final germination percentage (FG), mean daily germination (MDG) and germination rate (GR), were significantly affected by treatments and species (p 〈 0.01).
基金supported by the grant of the Natural Sciences and Engineering Research Council of Canada to A.U.I. (355753/2013)
文摘During germination of barley(Hordeum vulgare L.) seeds, important morphological and physiological changes take place, including development of organs and tissues and activation of metabolic pathways. Germination and dormancy of seeds are regulated by abscisic acid, gibberellins, reactive oxygen species(ROS), reactive nitrogen species(RNS)and several other factors. Activities of ascorbate-glutathione cycle enzymes, responsible for scavenging ROS, strongly increase. Catalase and superoxide dismutase activities, also scavenging ROS, decrease at the onset of seed germination and then increase. With the increase in aerobic metabolism after radicle protrusion, the activities of the fermentation enzymes lactate and alcohol dehydrogenase decline rapidly. The RNS-scavenging activity of S-nitrosoglutathione reductase decreases in the course of seed germination, in concert with elevation of nitric oxide production and protein nitrosylation. This activity supports the role of RNS in regulating seed germination. Transcription of various genes at different phases of seed germination exhibits phase-specific changes. During imbibition, genes involved in cell wall metabolism are highly expressed; in the middle phase of seed germination before radicle protrusion, genes involved in amino acid synthesis, protein synthesis, and transport and nucleic acid synthesis are upregulated significantly, and after radicle protrusion, genes involved in photosynthetic metabolism are induced. In summary, signal transduction and metabolic regulation of seed germination involve diverse reactions and complex regulation at different levels of metabolic organization.
基金supported by National Key Research and Development Program of China (2017YFC0505201)NSFC (grant 31670206 to Z.-M. L. and 31570228 to B. S.),major Program of NSFC (grant 31590823 to H. S.)+1 种基金the Orientation Training Programme for Postdoctoral Fellows from Yunnan Province to D.-L. P.the Young Academic and Technical Leader Raising Foundation of Yunnan Province to B. S.
文摘Seed dormancy and germination characteristics are important factors determining plant reproductive success, and may be expected to have a major influence on plant distribution. In this study, we aimed to explore the characteristics of seed dormancy and germination in two endemic Rheum species(Rheum nobile and Rheum alexandrae) in the Himalaya-Hengduan Mountains. To determine the type of dormancy,fresh seeds of the two species(one population each) were incubated in light at 25/15 and 15/5℃, and then dry after-ripening(DAR) seeds were incubated on water agar substrate with or without GA_3. To determine the effect of temperature and light on germination, DAR seeds of the two species(two populations each) were incubated both in the light and in the dark at several temperatures, including constant and alternating temperatures. Base temperature(T_b) and thermal times for 50% germination(θ_(50)) were calculated. DAR released physiological dormancy(PD), increasing final germination at 15/5℃ and widening the range of germination temperatures from higher to lower, indicative of type 2 non-deep PD for the two Rheum species. Light had no significant effect on germination of seeds from the two species(two populations each). Seeds of the two species germinated significantly better(>80%) at medium temperatures(10-25℃) than at extreme low(5℃) or high(35℃) temperatures. Alternating temperatures(25/15 and 15/5℃) did not significantly increase the final germination of the two species either in the light and in the dark, but it promoted seed germination more quickly than corresponding constant temperatures in the light in both Rh. alexandrae populations, especially at 15/5℃. Germination in response to temperature was well described by the thermal-time model at suboptimal temperatures. The estimated Tbvalues were 1 and 0.9℃, respectively, in two Rh. nobile populations; 4 and 4.1℃,respectively, in two Rh. alexandrae populations; θ_(50)(thermal time) were 100 and 125℃d, respectively in two Rh. nobile populations; 76.92 and 83.33℃d, respectively in two Rh. alexandrae populations. The dormancy type, and germination responses to temperature and light condition does not explain why the two Rheum species are distributed in contrasting habitats. However, these findings reflect an advantageous germination strategy of these two Rheum species to adapt to the same alpine environments.
文摘For improving seed germination of Prosopis koelziana and Prosopis juliflora, different treatments of seeds were conducted, including scarification with sulfuric acid 98% for 10 and 15 min, sandy paper, hot water for 5 and 10 min, potasium nitrate 0.1%, gibberellic acid at 250 mg·L^-1 and 500 mg·L^-1 and combinational treatment of scarification with gibberellic acid of 250 mg·L^-1 and 500 mg·L^-1. The results show that scarifications with sandy paper and sulfuric acids 98% were the most effective treatments on breaking seed dormancy and seed germination induction. Scarification with sulfuric acid 98% for 15 min was the best treatment. According to the positive effect of scarification and lack of reaction of seeds against KNO3 and gibberellic acid, the kind of seed dormancy was determined as exogenous.
基金supported by the Institutional Research Plan No.AV0Z60870520(erá)the research plans MSM 0021620834(Tichy)MSM 4674788501(patenka) that are financed by the Ministry of Education,Youth and Sports of the Czech Republic
文摘Low-pressure discharge is applied for stimulation of germination of two seed lots of Lamb's Quarters (Chenopodium album agg.) with different starting germinations (17%, 8%) and in different stages of dormancy. Different exposition durations with cold plasma treatment were applied. The variable of the ratio cumulative germination was calculated. The Richards' equation was used for curve-fitting and simulation of the growth curves. Population parameters, namely Vi - viability, Me - time, Qu - dispersion, and Sk - skewness, counted from the curves described the germination rate well. Significant differences among Qu confirmed the erratic dormancy and gradual germination of Lamb's Quarters. No difference in the Me parameter was found between two tested seed lots, and no interspecies characteristics were changed using low-pressure discharge. The results suggested that plasma treatment changed seed germination in Lamb's Quarters seeds.
文摘To achieve a good production of a crop, it is essential to know the ability of the species to successfully complete two critical stages in the life cycle such as germination and seedling establishment. In this paper we study in comparative form structure of the seed, the importance of tegument in dormancy, the effect of accelerated aging on seed germination and viability, and the early and late growth in J. curcas and J. macrocarpa. External morphology of the seeds allow difference and internally also the embryos show evident differences. J. macrocarpa germination is around 0% - 4%. The total removal of tegument showed a 50% increase and the other treatments between 0% - 10%. Aging accelerated by Tetrazolium test allowed a comparative analysis of VP and GP. J. curcas maintains both to 96 h, while J. macrocarpa the seed viability is registered along the all treatment. J. macrocarpa seeds have less synchronicity than those of J. curcas. ABA and JAs were detected in tegument of J. macrocarpa and J. curcas seeds. JA could have a roll in inhibition of germination of J. macrocarpa seeds. Early and late growth, FW and DW of root, hypocotyl, epicotyl and leaf of J. curcas were significantly different in both species.
文摘Magnolia sinica is one of the most endangered Magnoliaceae species in China.Seed biology information concerning its long-term ex situ conservation and utilization is insufficient.This study investigated dormancy status,germination requirements and storage behavior of M.sinica.Freshly matured seeds germinated to ca.86.5%at 25/15℃but poorly at 30℃;GA3 and moist chilling promoted germination significantly at 20℃.Embryos grew at temperatures(alternating or constant)between 20℃and 25℃,but not at 5℃or 30℃.Our results indicate that M.sinica seeds possibly have non-deep simple mor-phophysiological dormancy(MPD).Seeds survived desiccation to 9.27%and 4.85%moisture content(MC)as well as a further 6-month storage at-20℃and in liquid nitrogen,including recovery in vitro as excised embryos.The established protocol ensured that at least 58%of seedlings were obtained after both cold storage and cryopreservation.These results indicate that both conventional seed banking and cryopreservation have potential as long-term ex situ conservation methods,although further optimized approaches are recommended for this critically endangered magnolia species.
基金supported by National Natural Science Foundation of China(No.31830016 and 31800534)。
文摘Elucidating the regulatory mechanisms of environmental factors on seed dormancy and germination will provide guidance for tree regeneration.Toward understanding the coupled effect of light and temperature on dormancy release and germination of Pinus koraiensis seeds,we set up three light conditions(L200:200μmol m^(-2) s^(-1),L20:20μmol m^(-2) s^(-1),L0:0μm^(-2) s^(-1))and four storage temperatures[T-5:-5°C(50 days),T5:-5°C(50 days)+5°C(50 days),T25:-5°C(50 days)+5°C(50 days)+25°C(50 days),T15:-5°C(50 days)+5°C(50 days)+25°C(50 days)+15°C(50 days)]using imbibed seeds,then quantified phytohormones gibberellic acid(GA_(3))and abscisic acid(ABA)during the stratification.Germination percentage(G_(P)),mean germination time(T_(M)),and germination value(G_(V))under 25/15°C temperature and the three light conditions were then determined.Phytohormone levels and germination performances were significantly affected by light and temperature.No consistent trend was found between the phytohormone levels and G_(P) caused by light levels.Under the three light conditions,ABA concentrations in the embryo and endosperm decreased as storage temperature shifted from T-5 to T25 and increased from T25 to T15;GA_(3) decreased in nearly all four storage temperatures.G_(P) reached 40–60%in T25 storage without light irradiance.In the three light conditions,G_(P) and G_(V) were higher at T5 and T25 than at T-5 and T15;so T5 and T25 are considered as optimum storage temperatures for dormancy release and germination.At optimum temperatures,light(L200,L20)significantly increased the G_(P) and G_(V) compared with the dark(L0).At L200 and L20,significant negative correlations between G_(V) and the ABA concentrations and positive correlations between G_(V) and GA/ABA in the seed embryo were found.Temperature played a more important role in primary dormancy release and germination;light was unnecessary for primary dormancy release.Light facilitated seed germination at optimum temperatures.The dormancy release and germination of P.koraiensis seeds were controlled by a decrease in ABA concentrations or an increase in GA/ABA induced by temperature variations.
基金Supported by Hainan Spark Industrial Zone Project(HNXH201504)
文摘To improve understanding of Portulaca pilosa seed germination and lay technical foundation for seedling cultivation,this paper studies the characteristics of dormancy and germination of Portulaca pilosa seed. Research indicates that its primary seed dormancy period is about25 d,dormancy can be completely released by storage at room temperature for 30 d; the seed is positively photoblastic seed that can't sprout and can be induced into dormancy in low light conditions; the dormancy-released seed is more sensitive to light when compared with the freshly picked seed,and the germination peak arises 1 d earlier; Portulaca pilosa seed favorites humid conditions,and the higher the soil moisture,the higher the germination rate and germination energy of the seed. The dormancy-released seeds should be used for Portulaca pilosa seedling cultivation,and after the germination is accelerated for 2- 3 d in the light conditions,the seeds are sown on the soil surface,and covered with transparent plastic film to keep moisture and light,which is conducive to the emergence of seeds.
文摘Several Chinese Iris species have potential for medicinal and ornamental use, but they have poor, erratic or slow seed germination. The aims of this study was to classify Iris ehrysographes dormancy type and investigate the optimum treatment for seeds germination through examining the effects of various incubation temperatures, light conditions, scarification, stratification and soil substratum. Seed viability of/. chrysographes was 74% and seeds imbibed water very fast. No seeds germinated on stratification, soil substratum, constant or alternating temperatures, light and darkness treatments. Seeds germination of different mechanical restriction treatments had significant differences. The results indicated that: (1) removal of seed coat was the most effective treatment for/. chrysographes germination; (2) physiological dormancy phenomenon was found in this species.
基金funded by the National Natural Science Foundation of China(32072022)the Nanfan Special Project,CAAS(YBXM07)the Hainan Yazhou Bay Seed Laboratory,China(B23CJ0208)。
文摘The germination process of seeds is influenced by the interplay between two opposing factors,pectin methylesterase(PME)and pectin methylesterase inhibitor(PMEI),which collectively regulate patterns of pectin methylesterification.Despite the recognized importance of pectin methylesterification in seed germination,the specific mechanisms that govern this process remain unclear.In this study,we demonstrated that the overexpression of GhPMEI53is associated with a decrease in PME activity and an increase in pectin methylesterification.This leads to seed cell wall softening,which positively regulates cotton seed germination.AtPMEI19,the homologue in Arabidopsis thaliana,plays a similar role in seed germination to GhPMEI53,indicating a conserved function and mechanism of PMEI in seed germination regulation.Further studies revealed that GhPMEI53 and AtPMEI19 directly contribute to promoting radicle protrusion and seed germination by inducing cell wall softening and reducing mechanical strength.Additionally,the pathways of abscicic acid(ABA)and gibberellin(GA)in the transgenic materials showed significant changes,suggesting that GhPMEI53/AtPMEI19-mediated pectin methylesterification serves as a regulatory signal for the related phytohormones involved in seed germination.In summary,GhPMEI53 and its homologs alter the mechanical properties of cell walls,which influence the mechanical resistance of the endosperm or testa.Moreover,they impact cellular phytohormone pathways(e.g.,ABA and GA)to regulate seed germination.These findings enhance our understanding of pectin methylesterification in cellular morphological dynamics and signaling transduction,and contribute to a more comprehensive understanding of the PME/PMEI gene superfamily in plants.
基金supported by the Foundation of Major Projects in Hainan Province,China(ZDKJ202001)the Research Initiation Fund of Hainan University,China(KYQD(ZR)19104)。
文摘Salinity is one of the most significant risks to crop production and food security as it harms plant physiology and biochemistry.The salt stress during the rice emergence stages severely hampers the seed germination and seedling growth of direct-seeded rice.Recently,nanoparticles(NPs)have been reported to be effectively involved in many plant physiological processes,particularly under abiotic stresses.To our knowledge,no comparative studies have been performed to study the efficiency of conventional,chemical,and seed nanopriming for better plant stress tolerance.Therefore,we conducted growth chamber and field experiments with different salinity levels(0,1.5,and 3‰),two rice varieties(CY1000 and LLY506),and different priming techniques such as hydropriming,chemical priming(ascorbic acid,salicylic acid,and γ-aminobutyric acid),and nanopriming(zinc oxide nanoparticles).Salt stress inhibited rice seed germination,germination index,vigor index,and seedling growth.Also,salt stress increased the over accumulation of reactive oxygen species(H_(2)O_(2) and O_(2)^(-)·)and malondialdehyde(MDA)contents.Furthermore,salt-stressed seedlings accumulated higher sodium(Na^(+))ions and significantly lower potassium(K^(+))ions.Moreover,the findings of our study demonstrated that,among the different priming techniques,seed nanopriming with zinc oxide nanoparticles(NanoZnO)significantly contributed to rice salt tolerance.ZnO nanopriming improved rice seed germination and seedling growth in the pot and field experiments under salt stress.The possible mechanism behind ZnO nanopriming improved rice salt tolerance included higher contents of α-amylase,soluble sugar,and soluble protein and higher activities of antioxidant enzymes to sustain better seed germination and seedling growth.Moreover,another mechanism of ZnO nanopriming induced rice salt tolerance was associated with better maintenance of(K^(+))ions content.Our research concluded that NanoZnO could promote plant salt tolerance and be adopted as a practical nanopriming technique,promoting global crop production in saltaffected agricultural lands.
基金supported by the Key Research and Development Program of Shaanxi(2021NY-083)the National Natural Science Foundation of China(31871567).
文摘Low temperatures during germination inhibit seed growth,lead to small and weak seedlings,and significantly reduce the wheat yield.Alleviating the adverse effects of low temperature on wheat seed germination is highly important for achieving high and stable wheat yields.In this study,Tongmai 6(insensitive)and Zhengmai 113(sensitive),which have different low-temperature sensitivities during germination were treated with low temperature during germination.The transcriptome,metabolome and physiological data revealed that low temperature decreased the germination rate,downregulated the expression of a large number of genes involved in regulating glycometabolism,and inhibited carbon,nitrogen(especially amino acids)and energy metabolism in the seeds.Arginine content increased at low temperature,and its increase in the low-temperature-tolerant variety was significantly greater than that in the sensitive variety.Arginine priming experiment showed that treatment with an appropriate concentration of arginine improved the seed germination rate.The conversion of starch to soluble sugar significantly increased under exogenous arginine conditions,the content of key metabolites in energy metabolism increased,and the utilization of ATP in the seeds increased.Taken together,arginine priming increased seed germination at low temperature by relieving inhibition of seed carbon and nitrogen metabolism and improving seed energy metabolism.
基金supported by the Hainan Province Science and Technology Special Fund,China(ZDYF2023XDNY086)the Project of Sanya Yazhou Bay Science and Technology City,China(SCKJ-JYRC-2022-87)+1 种基金the Natural Science Foundation of Guangdong Province,China(2023A1515012052,2023A1515012092)the Science and Technology Project of Guangzhou,China(2023A04J0749,2023A04J1452).
文摘Seed germination is a complex trait regulated by multiple genes in rice.However,the regulators of rice seed germination have yet to be sufficiently determined.Here,a quantitative trait locus(QTL)for rice seed germination was identified in a genome-wide association study.The candidate gene JASMONATE ZIM-DOMAIN 5(OsJAZ5)of the QTL was verified that positively regulates seed germination.OsJAZ5 regulation of seed germination involves an OsABI3-mediated abscisic acid pathway.Overexpression of OsJAZ5 facilitated seed germination.The application of OsJAZ5 might be useful for increasing seed germination for rice direct seeding.
基金the Sichuan Science and Technology Program(2023NSFSC0214)China Agriculture Research System(CARS-07-B-1)+1 种基金National Natural Sciences Foundation of China(Nos.3230185031771716).
文摘To mitigate the wastage of seed resources and reduce the usage of pesticides and fertilizers, seed coating agentshave gained popularity. This study employs single-factor and multi-index orthogonal experimental design methodsto investigate the seed coating formula and physical properties of Tartary buckwheat. The specific effects ofeach component on Tartary buckwheat seed germination are analyzed. The findings reveal that the seed coatingagent formulated with 1.5% polyvinyl alcohol, 0.15% sodium alginate, 0.2% op-10, 0.1% polyacrylamide, 8% colorant,3% ammonium sulfate, 1% potassium dihydrogen phosphate, and 0.15% carbendazim exhibits the mosteffective coating. It demonstrates optimal physical properties and promotes seed germination efficiently. The suspensionrate of this seed coating agent reaches 91.12%, with a mere 2.13% coating shedding rate and 2.5% coatingseed rot rate. Furthermore, it achieves a germination percentage of 99.17%, which is 20.84% higher than the lowestgroup. The germination potential and index are also significantly higher than the lowest group, with anincrease of 20.84% and 26.56%, respectively. Additionally, the vitality index is 553.08, a 15.75% increase comparedto the lowest group. The application of seed coating agents helps reduce seed resource loss, increase plant numbers,and ultimately enhance agricultural yields. This finding holds practical significance in agriculturalproduction.
基金Supported by the National Major Special Project for the Cultivation of New Genetically Modified Biological Varieties(Topic ZX08011-003)。
文摘Amaranthus retroflexus L. is a serious and widespread malignant weed in soybean fields in Heilongjiang Province. Exploring the dormancy characteristics of A. retroflexus L. seeds and the physiological response of its seedlings to acifluorfen sodium can provide a basis for further researches on its resistance mechanism. Using newly harvested and stored A. retroflexus L. seeds for one year as experimental materials, the effects of different concentrations of HCl, NaOH, water temperature, gibberellic acid(GA) and polyethylene glycol(PEG) on the dormancy and germination of A. retroflexus L. seeds were studied. The sensitivity of A. retroflexus L.to acifluorfen sodium was determined using bioassay. The effects on leaf chlorophyll content and target enzyme activity were studied at a normal dosage of 360 g a.i. hm^(-2) and a doubling dosage of 720 g a.i. hm^(-2) of acifluorfen sodium. Newly harvested seeds exhibiting dormancy were soaked in water of various temperatures and in different concentrations of NaOH and HCl, which were ineffective in breaking the seed dormancy. GA could break seed dormancy, and the highest seed germination rate reached 93.33% when they were soaked at 3 000 mg·L^(-1) for 72 h and 4 000 mg·L^(-1) for 48 h. The drought stress was simulated with a 15%-25% polyethylene glycol solution, which had no significant effect on the seed germination rate. The GR_(50) value of acifluorfen sodium for A. retroflexus L. was 705.7 g a.i. hm^(-2), which was 1.96 times the recommended dose in the field. After the application of different doses of acifluorfen sodium, the chlorophyll content of A. retroflexus L. reached its minimum value 3 days after treatment(DAT), and then gradually increased. The activity of the target enzyme protoporphyrinogen oxidase(PPO) reached the highest value at 7 DAT under different dosages, and gradually returned to normal levels thereafter. Soaking with gibberellin was an effective method to break seed dormancy. A. retroflexus L. seeds had certain drought resistance during the germination process. A. retroflexus L. was not sensitive to acifluorfen sodium and acifluorfen sodium ether, and could not effectively inhibit the PPO activity, indicating that A. retroflexus L. had target resistance to acifluorfen sodium.
基金Supported by the International Science and Technology Cooperation Program(2008DFA31820)~~
文摘[Objective] The aim of this study was to provide the theoretical basis for screening and utilizing salt-tolerant tomato varieties as well as for cultivating salt-resistance.[Method] Salinity tolerance of tomato during seed germination under simple salt sodium chloride and double salt calcium nitrate or sodium chloride stress were studied by Petri dish culturing.[Result] As the two kinds salt concentration increased,the germination regularity,the germination rate,the germination index and the growing vigor index of tomato seedlings decreased,but the germination losing rate increased.When salt concentration was from 0.2% to 0.4%,there was little difference among all indexes under two kinds of salt stress.However,when salt concentration was from 0.6% to 1.0%,the difference among all indexes under two kinds of salt stress was significant.[Conclusion] Salinity tolerance of tomato seeds under double salt calcium nitrate or sodium chloride stress was higher than that under simple salt sodium chloride stress.
基金Key Project of‘Rejuvenating the Northeast China’ Science and Technology Action Plan of Chinese Academy of Sciences(DB2X-2-027)National Key Basic Research Program(2004CB418506)~~
文摘[ Objective ] The research aimed to reveal theeffects of excessive Mg^2+ on the germination characteristics of maize and soybean. [ Method ] Eleven concentration gradients of Mg^2+ including 0, 40, 80, 120, 160,200,240,280,320,360 and 400 mmol/L were set up to study the effects of different treatments on such indices as the germination potential, germination rate, fresh weight, dry weight, root length, plant height and stem diameter of maize and soybean. [ Result] With the increasing of Mg^2+ concentration, the germination of maize delayed and the germination rate of soybean obviously decreased, reaching the significant difference at 0.05 level. When Mg^2+ concentration increased, the fresh weight and dry weight of maize and soybean decreased, but maize and soybean showed some adaptability. The growth of radicles and seedlings in maize and soybean were obviously inhibited by Mg^2+ , and atrophy and dysplasia phenomena appeared. [ Conclusion] Excessive Mg^2+ stress has different effects on the germination potential and germination rate of different crops and has obvious poisoning effects on the root and stem growth of crops.
文摘[ Objective] The study was to understand the changes of amylase(AMY) and superoxide dismutase(SOD) isozymes during the ger- mination process of Emmenopterys henryi Oliv seeds. [ Metbod] By employing polyacrylamide gel electrophoresis method, the expressions of AMY and SOD isozymes during seed germination process were analyzed. ~ Result] The main AMY bands remained strong during the whole peri- od and a new band A2 appeared in the middle and late period of seed germination. Some new SOD bands occurred at the early stage, then be- came weak or disappeared in the middle period, and band S6 became intense in the late peried. [ Conclusion.] The expression of AMY and SOD isozyme gene has temporal difference during germination of E. henryi Oliv seeds.