Effects of polyamines on the early development of cystocarps,spore release,survival,and germination rate of Gracilariopsis lemaneiformis

Three polyamines(PAs)(spermidine(Spd),spermine(Spm),and putrescine(Put))were used as growth regulators to the marine macroalgae Gracilariopsis lemaneiformis and to female gametophyte and reproductive tissues(cystocarps were constructed),which led to early maturation of cystocarps and spore release.Laboratory cultivation revealed that exogenous PA application accelerated the development of cystocarps,and the mean sporeling growth rate was 20%–50%/d during the initial week of cultivation.The spore count(SC),survival rate(SR),and germination rate(GR)of G.lemaneiformis showed different responses to PA(10-6 mol/L and 10-3 mol/L)treatments under different temperatures(18,26,and 34℃),light intensities(30,60,and 90μmol photons/(m^(2)·s)),salinities(25,30,and 35),and nutrient levels(25꞉2.5,50꞉5.0,and 75꞉7.5μmol/L NH4Cl꞉K2HPO4),and the optimal conditions were 26℃,light intensity of 60μmol/(m^(2)·s),salinity of 35,and nutrient level of 50꞉5.0μmol/L NH4Cl꞉K2HPO4.Under the optimum conditions,the SC per cystocarp increased by 82.38%,and the spore SR and GR increased by 33.07%and 46.44%,respectively.Each experiment lasted for 7 days,with the highest SC on Day 4 and plateauing on Day 7.The results indicate that PAs could promote the early maturation,spore release,survival,and germination of G.lemaneiformis under laboratory conditions.

Primary Study on Influencing Factors of Rice Seed Germination Rate

In order to investigate the change rule of rice seed germination rate dur-ing the storage, the effects of moisture content and storage temperature on Lianjing 7 rice seed germination rate were investigated. The 3×3 factorial design was adopt-ed. The test data was analyzed using SPSS. The results showed that after the Lianjing 7 rice seeds with moisture content of 14.5% were stored at 25 ℃ for 180 d, the germination rate stil reached 89%; after the rice seeds with moisture content of 11.5% were stored at 5 ℃ for 180 d, the germination rate was up to 96.6%; the rice seed germination rate was decreased gradual y with the prolonging of storage time; the moisture content and storage temperature were two key factors affecting the Lianjing 7 rice seed germination rate, and there was significant interaction be-tween moisture content and storage temperature.

Effects of Different Processing Methods on Germination Rate of Wada Alfalfa Seeds

[Objective] To find a processing method to increase germination rate of Wada alfalfa seeds. [Method] Five processing methods were used to treat Wada alfaffa seeds, including immersion in hot water, immersion in 98% concentrated sulfuric acid, immersion in 100 g/L potassium nitrate, immersion in hot water after rubbing seed capsule, immersion in 30% （ V~ V） hydrogen peroxide. After treatment, germination energy, germination rate, germination index and vitality index were detected. [ Result] The Wada alfaffa seeds immersed in 25℃ water for 25 min after rubbing seed capsule had the highest germination rate （81.3%）, followed by that of seeds immersed in 100 g/L potassium nitrate for 2 h, that of seeds immersed in 50℃ water, and that of seeds immersed in 30% hydrogen peroxide for 5 min in order. The worst germination appeared in the seeds im- mersed in 98% concentrated sulfuric acid. [ Conclusion] Immersion in 25℃ water for 25 min after rubbing seed capsule is the best method to increase germination rate of Wada alfaffa seeds.

Seed germination and seedling development of Prunus armeniaca under different burial depths in soil

A semi-greenhouse study was conducted to understand the effects of soil burial depth on seed germination and seedling development. The seeds of wild apricot （Prunus armeniaca） were buried at the soil depths of 0-cm, 4-cm, 8-cm, and 12-cm, respectively, to simulate the seed hoarding behavior of rodents in the field. The results revealed that the rates of seed germination and established seedlings from buried seeds were both the highest in 4-cm burial depth group, and then decreased with increasing soil depth. The number of rotten seeds increased in deeper burial depth. It is unfavourable for seed germination at 0-cm burial depth （i.e., seeds were laid on soil surface）. There was insignificant effect of burial depth on growth of established seedlings. The results from this study indicated that proper burial depth in soil would be helpful for the seed germination and seedling growth. The seedlings derived from buried seeds at shallower depth （4 cm） in this research have advantage in their early development.

Effects of NaCl Stress on Seed Germination of Lycium ruthenicum Murr.

[Objective]To study the seeds germination of Lycium ruthenicum Murr.under different concentrations of NaCl,as well as to find the optimal concentration of NaCl for the germination of L.ruthenicum.[Method]The seeds of L.ruthenicum were treated with different concentrations of NaCl,and the state of seed germination was measured.[Result]With the increasing of concentration of NaCl,the seed germination rate of L.ruthenicum showed an obvious increasing trend.when the concentration was of 0.3%-0.4 %,the germination rate was the highest,and when the concentration of NaCl was greater than 0.4,the germination rate showed a decline trend.[Conclusion]After treated with appropriate concentrations of NaCl before sowing,the germination rate of seeds of L.ruthenicum would increase.

Effects of Magnetized Water on Seed Germination of Welsh Onion (Allium fistulosum L.)

With Welsh Onion seeds employed as materials, effects of magnetized water on seed Germination were studied. The results showed the treatment of magnetized water soaking for 4 h promoted water absorption rate and amylase ac- tivities of seeds significantly, which accelerated the transformation process of en- dosperm starch to soluble sugar, resulting in emergence of 36 hours in advance under low temperature condition. Germination rate and germination potential of magnetized water soaking were higher than the contrast by 6.7% and 10.0%, which helped cultivate vigorous seedling.

Study on Biological Characteristics of Adelostemma gracillimum Seeds

The effects of temperature, light, pH value and storage time on germina- tion of Adelostemma gracillimum seeds were studied through germination experi- ment. The results showed that A. gracillimum seeds had no property of post-matu- ration dormancy; the optimum germination temperature was 25 ~C; no significant difference was found in germination rate of A. gracillimum seeds between light and dark conditions; A. gracillimum seeds showed a wide adaptability to pH, Le., they could germinate in the pH range of 2-10, and showed a higher germination rate in the pH range of 6-8. The optimum storage time for A. gracillimum seeds was 12 months.

Influences of UV-C Irradiation on Seed Germination and Seedling Growth of Winter Wheat

[Objective] This study aimed to investigate the influences of UV-C irradiation on seed germination and seedling growth of winter wheat. [Method] Winter wheat cul- tivar Liaoda 02 was selected as the experimental material and irradiated with UV-C for 1 h,to compare the dynamic changes of seed germination rate under different treatment time and the changes of gibberellin （GA） content and a-amylase activity during the germination process after UV-C irradiation. Wheat seeds irradiated with UV-C for 1 h were sown, the emergence number, growth speed, fluorescence param- eter, reflectance spectrum, relative conductivity and other related physiological indica- tors of seedlings were determined. [Result] The results showed that the germination rate of dry and wet winter wheat seeds irradiated with UV-C for 1 h was improved, compared with the untreated seeds. After soaked for 6, 8, 10 and 12 h, dry seeds irradiated with UV-C for 1 h showed higher GA content and higher a-amylase activity than the control. In addition, UV-C-irradiated dry seeds also showed faster emergence speed and plant growth speed within the first six days after emergence and greater plant height than the control. The flavonoid content in leaves of the treatment group was also increased compared with the control, while the maximal photochemical effi- ciency （Fv/Fm）, photo-chemical reflectance index （PRI）, chlorophyll and carotenoid content were rarely influenced. In conclusion, UV-C irradiation could improve the ger- mination rate of dry seeds and wet seeds soaked for a certain time, especially for wet seeds soaked for 1 h. Furthermore, UV-C-irradiated seeds showed improved ger- mination speed and plant growth. [Conclusion] This study laid the foundation for ex- ploring the effect mechanism of ultraviolet rays on seed generation.

Effects of Different-concentration EMS on Germination of Tarary Buckwheat [Fagopyrum tataricum(L.) Gaertn] Seeds

[Objective] This study aimed to determine the optimum ethyl methane sulfonate（EMS） concentration for germination of tarary buckwheat seeds so as to lay a solid foundation for obtaining excellent traits of tarary buckwheat and breeding new varieties that meet the requirements by EMS mutation breeding. [Method] The seeds of Jinqiaomai No.4, a local tarary buckwheat variety [Fagopyrum tataricum（L.） Gaertn] in Shanxi Province, were used as the material. They were mutagenized by different concentrations（0.3%, 0.5%, 0.7%, 1.0%, 1.5%, 1.7%） of EMS for different times（4, 8, 12 h）. Then the germination rate and germination vigor were analyzed. [Result] With the increase of EMS mutagenic agent concentration, the germination vigor, relative germination vigor, germination rate and relative germination rate are all trended to be decreased. When the EMS concentrations ranged from 0.3%to 1.0%, there were no significant differences between treatment and control groups（P〉0.05）. When the EMS concentrations were 1.5% and 1.7%, significant differences were shown between treatment and control groups（P〈0.01）. The 4 and 8 h treatment of EMS all had no significant effects on germination rate and relative germination rate of Jinqiaomai No.4, but the 12 h treatment of EMS showed significant effects. Among the three treatment times, there were still no significant differences in germination vigor and relative germination vigor between treatment and control groups. [Conclusion] The optimum median lethal dose and treatment time of EMS for mutagenizing Jinqiaomai No.4 were 1.7% and 12 h, respectively.

Effects of Specific Gravity-based Seed Grading on Seed Germination, Seedling Emergence and Grain Yield of Hybrid Rice

Using the commercial seeds of two hybrid rice varieties including Lu- liangyou 996 and Liangyoupeijiu as the materials, four specific gravity-based seed grading treatments, Le., the specific gravity of 〈1.0 （T1）, 1.0-1.09 （T2）, 1.1-1.19（T3） and ≥1.2 （T4）, by selection with different saline solutions, and the control without seed grading （CK） were designed to study the effects of seed grading on seed germination, seedling emergence, seedling quality and grain yield. The results showed that the treatments of T2, T3 and T4 had higher or significantly higher seed germination rate, germination index and vigor index, seedling emergence rate and adult seedling rate than the CK, while T1 had significantly lower values of these traits than the CK. Compared with the CK, the number of spikelets per pani- cle was found to be the main reason for the yield increase of these treatments with high seed viability.

Effect of Different Treatments on the Germination and Seedling Growth of Firmiana simplex

With Firmiana simplex （L.） W. F. Wight as an experiment material, the effects of different concentrations of GA3 （Gibberellin A3）, SA （Salicylic acid） and NAA （1-Naphthalene acetic acid） and stratification on the germination rate of seeds were studied firstly, and then the effects of GA3 and NAA on seedling growth were analyzed. The results showed that the germination rate could be improved by 0.075 g/L SA and stratification markedly. It was indicated by the experiment that the growth of the main root and main stem could be promoted by 0.050 g/L and 0.077 g/L NAA, respectively. However, the leaf length and leaf width decreased significantly in the GA3 and NAA treatments.

Effects of Induced Concentration and Time of EMS on Seed Germination of Common Buckwheat

[Objective] This study aimed to investigate the effects of induced concen- tration and time of EMS on seed germination of common buckwheat. [Method] The seeds of Jinqiaomai No.3, a common buckwheat cultivar, were used as the test material, and their germination was induced by different concentrations of EMS un- der different induced times. The germination rate, germination vigor, relative germi- nation rate and relative germination vigor of Jinqiaomai No.3 were measured. [Re- sult] With increased induced concentration and time of EMS, the germination rate, germination vigor, relative germination rate and relative germination vigor of Jinqiao- mai No.3 were all trended to be decreased. For Jinqiaomai No.3, the optima in- duced concentration and time of EMS was 1.0% and 4 h, respectively, and the lethal concentration was 1.7%. [Conclusion] The induced concentration and time of EMS all showed significant effects on seed germination of Jinqiaomai No.3.

Effect of Seed-coating Agents on Rice Seeds with Dehiscent Glumes

In order to improve the utilization efficiency of hybrid rice seeds, the effects of seed-coating agents on hybrid rice seeds with dehiscent glumes were investigated. Total six kinds of seed-coating agents were selected, i.e., 20.5% imidacloprid ·prochloraz FS, 30.5% imidacloprid oprochloraz FS, 23.0% thiamethoxam · hymexazol·prochloraz FS, Ruisheng WS, Shileshi FS and Liangdun FS, and their effects of seeds of Longliangyou Huazhan and T You 272 were investigated. The results showed that when the percentage of glume-dehiscent seeds reached 10%, 20.5% imidacloprid .prochloraz significantly improved the germination rate of Longliangyou Huazhan, which was 4.33% higher than that in the control group, and the seedling rate of Longliangyou Huazhan remained unchanged; 30.5% imidacloprid. prochloraz did not improved the germination rate of T You 272, but improved its seedling rate, which was 7.66% higher than that in the control group. When the percentage of glume-dehiscent seeds reached 20%, 20.5% imidacloprid ·prochloraz and 30.5% imidacloprid.prochloraz improved the germination rate of T You 272 by 3.50% and 4.83%, respectively, and its seedling rate did not decline. In conclusion, seed-coating agents have certain repair effect on glume-dehiscent rice seeds; 20.5% imidacloprid ·prochloraz and 30.5% imidacloprid ·prochloraz could improve the efficiency of Longliangyou Huazhan and T You 272 with small amounts of glume-dehiscent 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.

IMPROVEMENT OF SANDY SOIL WITH WATER-CONSERVING MEMBRANE AND ITS EFFECT ON CROP GROWTH

Water-conserving membrane is a new material of improving sandy soil. It is based on the rule that a compound with organic and inorganic components can produce colloid after its integrating with Ca2+ in soil. The water-conserving membrane will obstruct capillary and increase viscidity of sandy soil, so as to decrease leakage and evaporation in sandy soil. The water-conserving membrane contains polyacrylic acid (PAA) and bentonite. When PAA concentration and pH of solution are different, water-conserving membrane can be made in different depth of soil. This experiment shows that the solution with 0.2% PAA does not harm and poison the crops, on the contrary, promotes crop germination. The solution with 0.2% or 0.4% PAA can accelerate corn growth. Accordingly, different crops need the application of the different PAA concentrations in the cultivation. Therefore, on the basis of different vadose coefficient in sandy soil, the solution with different PAA concentration can improve sandy soil and increase its water-conserving competence very well. The solution can be used to improve sandy soil and control desert enlargement in arid, semi-arid and semi-humid areas.

Evaluation on Sixty-eight Rice Germplasms in Cold Tolerance at Germination Stage

Sixty-eight rice germplasms were used for cold tolerance evaluation at the germination stage in laboratory. Seeds of rice germplasms germinated at three different temperatures containing low temperature （constant 13°C for 28 days）, alternative temperature （a temperature cycle of 12 h at 20°C and 12 h at 23°C for 14 days） and control （constant 26°C for 7 days）. Analysis of variance revealed that temperature had a significant effect on germination rate, coleoptile length and radicle length. Germination rate was strongly affected by the low temperature and alternative treatments. Stress of low temperature at the germination stage on the tested rice germplasms caused a reduction in final germination rate and the lengths of coleoptile and radicle. The normal and healthy seeds began to germinate within 36 h after imbibition and germination were completed on the 7th day in the control, but delayed under the low and alternative temperature treatments. The low and alternative temperature treatments delayed the growth of coleoptile and radicle compared to the control, and the average lengths of coleoptile and radicule were strongly inhibited with the decreasing temperature in all of the tested germplasms. Taichung, a semi-dwarf, low amylose content and early maturing rice variety, showed a significantly higher germination rate at the three temperature treatments and its coleoptile length was significantly higher than other germplasms.

In vitro culture of immature embryos from Koelreuteria bipinnata var. integrifoliola

For the mass production of Koelreuteria bipinnata var. integrifoliola with selected, hybrid or genetically engineered genotypes, one potentially desirable propagation strategy is based on embryo culture. The immature embryo development in vitro from K. bipinnata var. integrifoliola was studied under different conditions of embryo age, basic culture media and plant growth regulators. The results show that： 1） germination rate of grade 3 embryos in immature seeds with 0.6-0.8 cm diameter was 98.9%. The germination rate of grade 2 embryos in immature seeds with 0.4-0.6 cm diameter was 77,8% and the germination rate of grade 1 embryos in immature seeds with 0.4 cm diameter was 15.6%. 2） The amounts of macroelements in MS medium had no clear effect on the germination rate of immature grade 3 embryos and had a modest effect on plantlet growth, where the best medium was MS or 1/2 MS. The rates were all greater than 90%. 3） The germination rate of grade 3 embryos was greater than 87% when the medium contained a low concentration of NAA or no plant growth regulators at all and decreased markedly when BAP alone or BAP and NAA together were added to the media. We suggest that in vitro culture of immature embryos from K. bipinnata vat. integrifoliola can be enhanced when a small amount of plant growth regulators is added. The addition of BAP has an adverse reaction to the germination and development of immature embryos.

Nursery practice on seed germination and seedling growth of Dalbergia sissoo using beneficial microbial inoculants

Nursery practice using microbial inoculants was performed to find out the efficacy of the inoculants on seed germination and seedling growth of sissoo（Dalbergia sissoo Roxb.）.Microbial inoculants or effective microorganisms（EM） are a mixture of many different beneficial microorganisms in a solution.The seedlings were grown in a mixture of sandy soil and cowdung（3：1） kept in polybags with pouring EM solution at different concentrations（0.1%,0.5%,1%,2%,5% and 10%） before and after a week of sowing the seeds.Seed germination rate and growth parameters of seedlings were measured,such as,shoot and root length,vigor index,fresh and dry weight of shoot and root and total biomass increment.The nodulation status influenced by EM was also observed along with the measurement of pigment contents in leaves.The highest germination rate（69%） was observed in 2% EM treatment,followed by 67% and 65% in 1% and 5% EM.The highest shoot length（33.2 cm） was in 2% EM,whereas highest root length（26.3 cm） was in 1% EM.Both fresh and dry weights from shoot and root,were maximum（4.16 g and 1.57 g;2.12 g and 0.83 g respectively） in 2% EM and were significantly（p ≤ 0.05） different from control.Vigor index was highest（4071） in 2% EM,which was significantly（p ≤ 0.05） different from control.Total dry weight increment was highest in 2% EM treatment,followed by 1% and 5% concentrations of EM.Nodulation number was higher at very low（0.1%） concentration of EM solution but it normally decreased with the increase of EM concentrations.The contents of chlorophyll a,chlorophyll b and carotenoid were highest（60.11,17.05 and 42.48 mg·L1respectively） in 2% EM treatment and lowest（39.35,13.55 and 27.29 mg·L-1 respectively） in control treatment.Therefore,low concentration of EM（up to 2%） can be used for getting maximum seed germination rate and seedling development of Dalbergia sissoo Roxb.

Effect of seed treatment for laboratory germination of Albizia chinensis

Seeds of Albizia chinensis（Osb.） Merr. in addition to water were also treated with different treatments by incubating in ethyl alcohol, acetone, and petroleum ether at room temperature for different durations. Seed heat treatment was done at temperatures of 30, 40 and 60℃ for different durations up to 24 h. To overcome dormancy caused by the impermeable seed coat, seeds were nicked and also treated with concen- trated sulphuric acid for different durations. Seeds responded to treat- ments with sulphuric acid and nicking only. Treatment with sulphuric acid for 20 and 30 min showed maximum germination at all incubation temperatures as compared to untreated controls and seeds treated with sulphuric acid for 10 min and nicking. Seedling length was greatest from seeds treated with sulphuric acid for 20 and 30 min and incubated at 30 ℃. Seedling dry weight was highest from nicked seeds incubated at 20℃ The most favourable incubation temperature was 30 ℃ as evidenced from GR （germination rate index） and Gv （germination value）. After ascertaining the seed response and performance we recommend that seeds ofAlbizia chinensis be treated with sulphuric acid for 20 or 30 min and incubation temperature of 25 to 30℃.

Effects of High Temperature Treatment on Seed Germination of Dodonaea viscosa(L.) Jacq

Seeds of Dodonaea viscosa （L.） Jacq, a representative species in dry and hot valleys in Southwest China, were chosen as experimental materials. In this experiment, the D. viscosa seeds were treated at 40, 60, 80 and 100℃ respectively before germination to study impacts of high temperature treatment on their generation rate and to further discuss the roles of fire during the process of vegetation formation in dry and hot valley areas of China. The results show that when the temperature was higher than 40 ℃, the germination rate of D. viscosa seeds was significantly higher than that of the control group, and the heat shock effect was apparent. The germination rate was the highest when the seeds were treated at 80 ℃ for 10 min, reaching 63.00%±2.55%. There was still a significant heat shock effect on the D. viscosa seeds which were stored for one year. In comparison with the conventional method of soaking seeds in hot water, the germination rate of D. viscose seeds which were treated at high temperature before germination increased significantly.