Effects of Antimony Stress on Root Growth,Antimony Accumulation and Physiological Characteristics of Ramie(Boehmeria nivea(L.) Gaudich.)

[Objectives]This study was conducted to investigate the toxicity of heavy metal antimony(Sb) to ramie(Boehmeria nivea(L.) Gaudich.) and the tolerance response in ramie. [Methods] A pot experiment was conducted to study the effects of Sb stress on root growth and Sb accumulation and transport of the root system of cultivated ramie Zhongzhu No.1, as well as on the physiological characteristics of ramie leaves. [Results] The plant height and root dry weight and volume of Zhongzhu No.1 showed an effect of "promoting at low concentrations and inhibiting at high concentrations" with the increase of Sb concentration, and decreased significantly at the concentration of 4 000 mg/kg, but no obvious toxic growth symptoms were observed. The content of Sb in roots(289.7-508.6 mg/kg) and the root-shoot transfer factor(0.09-0.57) of Zhongzhu No.1 increased with the increase of soil Sb concentration, but the change of Sb bioconcentration factor in roots was opposite, indicating that high concentrations of Sb in soil could promote the absorption of Sb in roots and the transport of Sb to the aboveground part, but the Sb enrichment capacity of roots was relatively reduced with the increase of soil Sb. Sb stress had a certain impact on the physiological characteristics of ramie leaves. With the increase of Sb treatment concentration, MDA, POD and SOD showed a change trend of "first increasing and then decreasing", while CAT gradually increased, indicating that Sb stress caused changes in the physiological characteristics of ramie leaves, thereby affecting plant growth and development. [Conclusions] This study provides a theoretical basis for ecological restoration of ramie in mining areas.

Physiological characteristics changes of Aesculus chinensis seeds during natural dehydration

A study was conducted to determine the physiological characteristics changes of Aesculus chinensis seeds during natural dehydration in 2003. The results showed that A. chinensis seeds were recalcitrant with being highly desiccation-sensitive. The seed moisture content of fresh fruits was higher than 60%. When the seeds were naturally dried for 30 days, their moisture content declined to 30.2% and their viability was completely lost. The seed germination percentage had a small increase at the beginning of desiccation and then decreased rapidly. The relative electrical conductivity of the A. chinensis seeds increased along with a decrease in seed moisture content. However, there was an abnormal increase in relative electrical conductivity when the seed moisture content was between 53.7% and 50.9%. Superoxide dismutase （SOD） activity decreased rapidly in the period of desiccation except for an abnormality when the seed moisture content was between 53.7% and 50.9%. Malondialdehyde （MDA） content increased slowly at the early stage of desiccation and then rose rapidly after the moisture content was below 50.9%. The soluble sugar content in seeds slowly increased with the increasing period of desiccation. The seed germination percentage was at the high level when seed moisture content was in range of 47%- 60%, which suggests that this was the optimum moisture content for maintaining A. chinensis seed viability.

Effects of Sunflower Artificial Aging on Seed Vigor and Physiological Characteristics

[Objective]The aim was to study the effects of sunflower artificial aging on seed vigor and physiological characteristics.[Method] The varieties of seed germination capacity,vigor of germination,germination index,vigor index,peroxidase（POD） activity,superoxide dismutase（SOD） activity and malondialdehyde（MDA） content for four sunflower germplasms such as＇SunM20＇,＇Deep Purple Minle＇,＇Da San Kui Hua 4＇and＇Ji Kui 24＇were studied under high temperature and high humidity conditions（100% RH,45 ℃） for different days（0 d,2 d,4 d,6 d,8 d,10 d）.[Result]The result showed that the germination capacity,vigor of germination,germination index,vigor index,POD activity,SOD activity declined gradually with the increase of seed aging days,whereas MDA content enhanced by degrees;The diggerences of resistance to artifical aging existed among the four accessions,＇SunM20＇was the most resistant one,and exhibited the strongest seed vigor,highest activities of two protective enzyme（POD,SOD） and lowest content of MDA at the uniform condition,moreover,the seed vigor and protective enzyme activities of＇SunM20＇changed slowest among the four materials during the aging process.[Conclusion]The distinct reduction of POD,SOD activities maybe the main reasons for the decrease of sunflower seed vigor at the artificial aging,and the gradual accumulation of a few MDA accelerated seeds aging.

On the Growth and Physiological Characteristics of Rice under Smashing Ridge Tillage

Two-line super hybrid rice （Oryza sativa L.） Guiliangyou 2 was taken as the experimental variety, the growth and physiological characteristics of rice under conventional tillage and smashing ridge tillage were compared based on field re- search. The results showed that smashing ridge tillage was beneficial to the tillering growth of rice plants in the the middle and later periods of tillering; under the tillage mode, the white root was more, the vigour was strong during the whole growing period, the SPAD was extremely significantly higher than that of conventional tillage, the net photosynthetic rate of the leaves was high and held green long, which were beneficial to the production and accumulation of photoassimilates; during mature pe- riod, the dry matter accumulation of the overground part under smashing ridge tillage was significantly higher than that of conventional tillage, and the number of productive ears under smashing ridge tillage was more than that of conventional tillage by 27.6×10^4/hm2, thus, the yield-increasing effect was significant and in- creased by 20.36%.

Salt Stress Effect on the Growth and Physiological Characteristics of Three New Varieties of Lagerstroemia indica

The effects of different concentrations of NaCI （0, 0.10%, 0.25%, 0.40%, 0.55%, 0.70%） on the growth and physiological characteristics of three new varieties of Lagerstroemia indica were studied by pot experiment in the plastic greenhouses. The results showed that under different NaCI concentrations, the relative height in- crement and the relative diameter increment of L. indica were restrained obviously; the contents of chlorophyll a, chlorophyll b, carotenoid and GSH decreased with in- crease of NaCI concentration; and the content of MDA increased with increase of NaCI concentration. Through the determination and comparison of physiological in- dexes, and analysis of correlativity, NaCI tolerance of the three new L. indica vari- eties ranked as L. indica ＇Pink Velour＇〉L. indica ＇Dynamite＇〉L. indica ＇Red Rock- et＇. This is consistent with the results of the morphological characteristics after Na- CI stress.

Effects of Low Light on Agronomic and Physiological Characteristics of Rice Including Grain Yield and Quality

Light intensity is one of the most important environmental factors that determine the basic characteristics of rice development. However, continuously cloudy weather or rainfall, especially during the grain-filling stage, induces a significant loss in yield and results in poor grain quality. Stress caused by low light often creates severe meteorological disasters in some rice-growing regions worldwide. This review was based on our previous research and related research regarding the effects of low light on rice growth, yield and quality as well as the formation of grain, and mainly reviewed the physiological metabolism of rice plants, including characteristics of photosynthesis, activities of antioxidant enzymes in rice leaves and key enzymes involved in starch synthesis in grains, as well as the translocations of carbohydrate and nitrogen. These characteristics include various grain yield and rice quality components （milling and appearance as well as cooking, eating and nutritional qualities） under different rates of shading imposed at the vegetative or reproductive stages of rice plants. Furthermore, we discussed why grain yield and quality are reduced under the low light environment. Next, we summarized the need for future research that emphasizes methods can effectively improve rice grain yield and quality under low light stress. These research findings can provide a beneficial reference for rice cultivation management and breeding program in low light environments.

Effects of Phosphine on Germination and Physiological Characteristics of Rice Seeds

[Objective] This study aimed to investigate the effects of phosphine on germination and physiological characteristics of rice seeds. [Method] Simulation envi- ronments were conducted to study the effects of high-level phosphine on germination status and physiological characteristics of rice seeds and explore the early environ- mental and ecological effects of phosphine on rice growth in phosphorus cycle of paddy field. [Result] Experimental results showed that the increase of phosphine con- centration in the environment resulted in the decrease of germination rate and ger- mination potential by 11.11% and 19.71%, respectively. In addition, the activities of catalase （CAT） and peroxidase （POD） were reduced to 94.35% and 92.61%, respec- tively; the content of malondialdehyde （MDA） was maximally increased by 29.11%, indicating that both germination potential and growth condition of rice seeds were in- hibited under conditions of high-level phosphine. [Conclusion] This study provided theoretical basis for investigating the effects of phosphine on germination of rice seeds under natural environment.

Effects of Accelerated Aging on Physiological and Biochemical Characteristics of Waxy and Non-waxy Wheat Seeds

Experiments were conducted to evaluate the physiological and the biochemical characteristics of waxy wheat seeds under accelerated aging conditions. Five waxy wheat lines, which were Waxy 1, Waxy 4, Waxy 8, Waxy 9, and Waxy 15; and five non-waxy wheat lines： S-39, 04J89, Jan-81, III42-4, and II110 were studied. The seeds were subjected to accelerated aging at 40℃, 45℃, 50℃, 55℃, and 60℃, and 90% relative humidity for 0, 2, 4, 6, and 8 days, respectively. The results showed a gradual increase in conductivity and decrease in germination rate during accelerated aging. SOD, POD and CAT activities increased at lowgrade treatment, but decreased at severe treatment. On the other hand, the soluble protein content decreased at 45 ℃, but successively increased, then decreased 50℃. From the above study, it showed that 90% RH at 55℃ was the best accelerated aging condition for optimum efficiency in a shorter period.

Effects of Crop Rootzone Non-Pressure Subirrigation on Tomato Physiological Characteristics, Yield, and Quality

The purpose of this article is to study the effects of different water elevations of non-pressure subirrigation on some indexes of tomato, including soil water status around crop rootzone, morphological indexes, physiological indexes, photosynthetic indexes, yield, quality, and water use efficiency. With the tomato materials of Dongsheng 1, the irrigation experiment was carried out in the greenhouse, and significance analysis was done on the experiment data through the software of DPS. The results showed that different water elevations, had significant influence on the growth, yield, and quality of tomato. The yield of the 6-cm treatment was the highest, the 3-cm treatment was inferior to the 6-cm treatment, and the 0-cm treatment was the lowest. However, the WUE was 0 cm 〉 3 cm 〉 6 cm. The sugar/acid and soluble protein was the highest under the 0-cm treatment, and the content of ascorbic acid did not decrease considerably. When compared to the 0-cm treatment, the ascorbic acid content of 6-cm and 3-cm treatment increased by 19.2 and 6.8%, respectively. These irrigation methods can satisfy the requirements of tomato growth; different water elevations have different influences on the tomato soil water status around crop rootzone, the physiological characteristics, and yield. It also harmonized the percentage between sugar and acid, increased the content of soluble protein and ascorbic acid, and made tomato more delicious. The irrigation methods can improve the quality of tomato by water control, which is worth promoting in the agricultural production.

Effects of different nitrogen forms and concentrations on seedling growth traits and physiological characteristics of Populus simonii × P. nigra

Numerous growth and physiological variables of 3-week-old Populus simonii × P.nigra seedlings were assessed after treatment with either nitrate nitrogen(NO_(3)^(−)--N)(0.1,0.5,1,5,or 10 mmol·L^(−1)) or ammonium nitrogen(NH_(4)^(+)+-N)(0.1,0.5,1,5,or 10 mmol·L^(−1)) to determine the best nitrogen form and concentration to optimize growth,biomass allocation,pigment content,and photosynthetic capacity.The results of combining membership function and an evaluation index suggested that,5 mmol·L^(−1) nitrogen,regardless of the form,yielded the highest comprehensive evaluation index and good growth.In addition,a Pearson correlation analysis and network visualization revealed that the total mass,shoot mass,root mass,leaf dry mass,plant height,leaf area,chlorophyll a and total chlorophyll had a physiological index connectivity degree≥15 for both nitrogen forms.Net photosynthetic rate,stomatal conductance,transpiration rate,maximum photochemical efficiency of PSII,total nitrogen content,ground diameter,chlorophyll b,and carotenoid were unique indices for evaluating NH_(4)^(+)+-N-based nutrition,which could provide a theoretical basis for evaluating the effects of nitrogen fertilizer on seedlings,cultivation periods,and stress tolerance in P.simonii× P.nigra.

Physiological and Biochemical Characteristics in Flag Leaves of the C Liangyou Series of Hybrid Rice Combinations at Late Growth Stages

The contents of chlorophyll, soluble sugars, soluble proteins and thiobarbitudc acid reaction substance （TBARS）, chlorophyll fluorescence parameters, net photosynthetic rate as well as the activities of superoxide dismutase （SOD） and peroxidase （POD） of flag leaves at the late growth stages were studied by using C Liangyou series of hybrid rice combinitions as material and Shanyou 63 as control. The C Liangyou series of hybrid rice combinations used in the experiment included C Liangyou 396, C Liangyou 87, C Liangyou 755 and C Liangyou 34, which all used C815S as male sterile line. The contents of chlorophyll, soluble sugars and soluble proteins in flag leaves of the C Liangyou series combinations at the late growth stages were higher than those of the control, whereas the TBARS content was lower than that of the control. The activities of SOD and POD were significantly higher than those of the control on the 7th day after heading, and then decreased slowly. ~bps, value and qp value of flag leaves decreased at the late growth stages, and these two parameters in flag leaves of the C Liangyou series combinations were higher than those of the control, while the qN value increased at the late growth stages and was lower than that of the control. The net photosynthetic rate of flag leaves at the late growth stage was higher compared with the control. These results suggest that slow senescence and strong photosynthetic capability in flag leaves at the late growth stages are the physiological basis of the C Liangyou series combinations.

Changes of Physiological Characteristics and Yield in Peanut Varieties with Different Resistance Effected by Peanut Scab

In order to identify the resistance of peanut varieties against scab disease, the changes of physiological characteristics and yield in two peanut varieties ＇Heyou 13＇ and ＇Quanhual0＇ with different resistance effected by peanut scab were stud- ied in field experiment by spray. The results showed the soluble sugar increased firstly and then decreased both in the resistant and susceptible peanuts after inocu- lation. Compared with the control, the soluble sugar of resistant peanut was higher, and that of the susceptible peanut was lower, which implied that the peanut resis- tance to scab was positive correlated with soluble sugar content. The soluble pro- tein content in leaves of resistant and susceptible peanut varieties after inoculation was higher than that of the control. The peak of soluble protein content appeared earlier in the susceptible peanut than in the resistant peanut, which indicated that the susceptible peanut were more sensitive to the pathogen than the resistant peanut. The leaf SOD activity increased firstly and then decreased both in resistant and susceptible varieties, while the decrease in the resistant variety were lower than in the susceptible variety. With the growth process, the CAT and POD activities first decreased, then increased, and again decreased. Compared with the corresponding control, the resistant variety had relatively higher CAT and POD activities than the susceptible variety, which illustrated that the protective enzymes played important roles in resistance mechanism to scab. The MDA content of the two peanut vari- eties after inoculation increased, indicating that plasma membranes were subjected to different degrees of damage. The yield of resistant and susceptible varieties after inoculation reduced, while the yield of the susceptible peanut of ＇Quanhua 10＇ reduced greater.

Effects of Artificial Aging on Physiological Characteristics and Seed Vigor of Medicago ruthenica Seeds

As shown by the changes in physiological characteristics and seed vigor of three Medicago ruthenica samples during artificial aging process, the germination potential, germination rate, germination index, vigor index and simple vigor index declined with the extension of aging time on the whole. After artificial aging for 6 min, the vigor was higher than that of the control. The conductivity, malondialdehyde content and soluble polysaccharide content of seed leachate increased with the aging time and negatively correlated （ P 〈 0.05） with the seed vigor indicators. The physiological indicators were very significantly correlated （P 〈 0.01 ） with the vigor indicators in the Medicago ruthenica sample from Dorbod Qi, UIanqab City（China）.

Effects of Traffic Stress on the Physiological Characteristics of Agrostis stolonifera

[Objective] This study aimed to investigate the effects of traffic stress on the physiological characteristics of Agrostis stolonifera under high temperature and humidity in summer. [Method] Total 3 creeping bentgrass varieties （lines） were se- lected as materials, and their physiological characteristics were determined and ana- lyzed, including leaf relative water content, relative plasma membrane permeability, peroxidase activity, superoxide dismutase （SOD） activity, catalase activity, proline content and malondialdehyde （MDA） content. [Result] Under the traffic stress, the leaf relative water content, relative plasma membrane permeability, MDA content, proline content and protection enzymes activities showed significant differences among different traffic intensities and tested varieties （P〈0.05）. The variations of various physiological indexes of Yuexuan 1 were smallest, and it showed relatively strong traffic tolerance. [Conclusion] Considering the traffic tolerance, the 3 tested creeping bentgrass varieties ranked as Yuexuan 1〉New Strain No.2〉Penncross.

Low Doses of Ionized Radiation and Hypomagnetic Field Alter Redox Properties of Water and Physiological Characteristics of Seeds of the Highest Plants

The influence of a 40-fold attenuated geomagnetic field and its combined action with low doses of α- and γ-irradiation on the physiological characteristics of seeds of the highest plants and redox properties of water was investigated. It established the reduction of seed germination both under direct and indirect effects due to water action of attenuated geomagnetic field. A negative effect of hypomagnetic field on grown characteristics of seeds under indirect effect via water was decreased by the low doses of γ-irradiation, and was increased by low doses of α-irradiation, i.e. ionized radiation was the dominant factor in their combined action. It was revealed the increasing of the value of the oxidation-reduction potential of water under the influence of low-intensive α-ir-radiation (239Pu), γ-irradiation (137Cs) and also that the magnetic induction attenuated pointing to a natural decline. The increasing of the oxidation-reduction potential value testifies about “the regular decreasing of internal energy of water molecules” and the increasing of its oxidative properties, which, in our opinion, is caused the inhibition of the germination of seeds. It is supposed that namely water is the main component in the effects of studying factors on bio-objects, which acts due to the alterations of the properties and structural content of water.

Changes in Physiological and Biochemical Characteristics of Floral Organ Development in a Soybean Cytoplasmic-nuclear Male Sterile Line

[Objectives]This study was conducted to explore the mechanism of soybean cytoplasmic-nuclear male sterility.[Methods]With soybean cytoplasmic-nuclear male sterile line JLCMS9 A and its homotype maintainer line JLCMS9 B as experimental materials,the activity of superoxide dismutase(SOD),peroxidase(POD)and catalase(CAT),malondialdehyde(MDA)content,starch content,soluble protein content,soluble sugar content and free proline content in flower buds,alabastrums and mature flowers were determined,and the contents and changes of auxin(IAA),gibberellin(GA3),isopentenyl adenosine(iPA)and abscisic acid(ABA)at the three stages were analyzed.[Results]The activity of SOD and CAT and the contents of MDA and free proline in the sterile line at the flower bud stage were lower than those of the maintainer line,but the opposite was true at the alabastrum stage and the flowering stage,and their values were higher than those of the maintainer line;the POD activity of the sterile line was significantly lower than that of the maintainer line at the flower bud stage,and the opposite was true at the alabastrum stage and the flowering stage,and its values were higher than those of the maintainer line;and the starch content and soluble sugar content of sterile line 9 A showed an overall upward trend,and were significantly lower than those of the maintainer line 9 B at the alabastrum stage and the flowering stage.During the whole development process of floral organs,the content of IAA in sterile line 9 A showed a trend of first increasing and then decreasing,and the content of iPA increased gradually.The contents of hormones in the sterile line were lower than those in the maintainer line.The ratios of IAA/ABA,IAA/GA3,IAA/iPA and ABA/GA3 in the sterile line were significantly different from those in the maintainer line.It is inferred that the abnormal physiological characteristics of floral organ development are related to the cytoplasmic-nuclear male sterility of soybean.The alabastrum stage may be a critical period for the occurrence of abnormal physiological and biochemical indexes in the floral organs of soybean cytoplasmic-nuclear male sterile lines.[Conclusions]This study provides a theoretical basis for the breeding of fine sterile lines of soybean and the research on the mechanism of sterility.

Effect of Low Concentration of Yttrium on Physiological Characteristics of Cucumber (Cucumis Sativus L.)

There is no doubt that rare earth elements stand an important position among the essential elements of plant growth and it is long time since they are first used as plant growth promoters. Given their effects on microstructure, most reports are focused on the toxicology rather than promotion. Using cucumis sativus L. (Jin Chun No.5) as experiment material, we try to find out the nutritional effects of low Y3+ concentrations on cucumber seedlings′ leaves. The present paper suggests that the rare earth elements act as micronutrients at low concentrations while they give rise to toxicity at high concentration. Benefits defeat toxicity with concentration ranging from 5 to 25 μmol·L-1. Through careful study, at the Y(NO3)3 concentration of 10 μmol·L-1 the content of chlorophyll as well as the activities of SOD, Cu-Zn SOD and the POD are the highest. It indicates 10 μmol·L-1 is the optimum concentration of yttrium for promoting the cucumber growth.

Effect of La-Gly on Physiological and Biochemical Characteristics of Glycine max Seedling under Pb Stress

The physiological and biochemical characteristics of Glycine max seedlings were changed under the high concentration of Pb stress, in which the malony dialdehyde (MDA) content, plasmalemma, activities of catalase (CAT) and peroxidase (POD) were increased drastically. The damage effects of Pb were reduced when 15 mg . L-1 La-Gly was used to spray Glycine max seedlings. The results of La-Gly treatment show that the effects are related to the decrease of Pb content in plants, the increase of photosynthetic rate and nitrate reductase (NR) activity, decrease of MDA content and cell membrane permeability, and maintenance of activities of CAT and POD.

Effect of Shading on Growth and Physiological Characteristics of Alfalfa, Medicago sativa

In order to select the suitable alfalfa varieties for the shade areas in vineyard of Northwest, four shasing treatments Ro, R1 , R2, R3 （ full light, 60% of full light, 30% of full light, 10% of full light） were set in the experiment to study the growth and physiological characteristics of seven domestic and foreign alfalfa varieties. The results showed that there was a big difference in height of alfalfa among cuhivars under shading; leaf area, leaf dry weight and leaf number reduced significantly with the decrease of light intensity （ P 〈 0.05 ） ; relative growth ratio, soluble sugar content, chlorophyll a/h decreased with the increase of shading in- tensity. The first harvest yield decreased significantly with the increasing shading intensity, AmeriStand and Queen declined less than others. In summary, the suit- able alfalfa cultivars for plantation were Queen, Alfalfa and AmeriStand in the northwest area where the habitat was similar with the habitat of experimental site, but due to the relativity of shading ability, the shading intensity could not exceed 50%.

The Differences of Physiological Characteristics and Yield of Northern Japonica Rice in Different Nitrogen Application Patterns

The research performed analysis on differences of physiological property and yield of Tiejing No. 11 by different nitrogen fertilization patterns. The results indicated that while the nitrogen of basal: tillering: panicle was 6 ∶3∶1, the higher amount of nitrogen improved the chlorophyll content, photosynthetic capacity, effective panicle, grain weight and yield; the medium nitrogen level had advantage under the ratio 4:3:3; nitrogen application at lategrowth stage was suitable for low or medium nitrogen level,which could increase photosynthetic capacity and optimize the yield components and increase yield; under the same ratio for basic tiller and ear fertilizer, the increase of nitrogen could improve total nitrogen uptake and protein content, decrease nitrogen physiological efficiency and milled rice and tasting, but nitrogen recovery and harvest index changes had difference; as application at late growth stage in same nitrogen rate, total nitrogen uptake and protein content increased, nitrogen physiological efficiency and milled rice and amylose content and tasting decreased, nitrogen recovery and harvest index increased under low or medium nitrogen level and decreased under high nitrogen level. Nitrogen application 210 kg/hm^2 and the ratio 4 ∶3 ∶3 of basal:tillering: panicle made the yield increase by 2.8%-11.3%, and this is the optimal mode of nitrogen fertilizer application.