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.

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 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 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.

Physiological and Biochemical Characteristic of a Stripe Mutant with Abnormal Flower Organs in Rice

[Objective] The experiment aimed to explore physiological and biochemical changes of leaves after plants were mutated. [Method] A rice double mutant with stripes on stems, leaves and spikelets were taken as experimental materials to study the enzyme activity changes in different growth stages and amino acid variation in rice. [ Result] The SOD activity in mutant was higher than that in wild plant at tillering metaphase, but lower than that in wild type before heading stage and late flowering; the POD activity in three stages increased firstly then declined and the activity showed highest maximal activity at before heading stage. However, the POD activity in wild type showed the opposite change trend; the CAT activity presented degression at three stages, especially high at tillering metaphase, but reverse changes in wild type; the MDA activity decreased at three stages, but it was still higher than that in wild type, besides, the soluble sugar content of mutant was lower, but total amino acid content was increased. [ Conclusion] The expression of mutant characteristics was correlated with SOD, POD, CAT and MDA activity Changes and these changes made the mutant survive and rice quality change at last.

Physiological and Biochemical Response of Artificial Wetland Plant under Electric Field

By measuring wetland plants chlorophyll content,malondialdehyde(MDA) content and superoxide dismutase(SOD) enzyme activity,the changes of wetland plant physiological characeristics under different power strength were studied,and the mechanism of electric field on plant physiological characteristics was analyzed to provide a theoretical basis for the pollutant removal ability strengthening of artificial wetland under electricfield.The results showed that compared with the control plants,low-intensity-voltage(1 V and 3 V) had no significant effect on the normal physiological and biochemical indexes of the plants,and the growth trend was better than the control group;with the voltage increasing,plant chlorophyll content,MDA content and SOD activity were greatly affected,indicating that plants were under strong oxidative stress,and the growth was damaged.Therefore,a suitable electric field could enhance the sewage treatment effect of constructed wetland.

Impacts of X-ray irradiation on Saccharomyces cerevisiae cells growth and physiological-biochemical characteristic

In this paper, the growth curves of yeast cells exposed to X-rays were detected, and then fitted by Gompertz equation. The yeast cells treated with 50–125 Gy showed an increased exponential growth rate, and lower total biomass at plateau. At doses ≥ 150 Gy, cells showed a decreased exponential growth rate and higher total biomass at plateau. DNA lesions were detected by comet assay. Meanwhile, intracellular accumulation of reactive oxygen species(ROS), reduction of mitochondrial membrane potential(?Ψ m) and cell membrane integrity were evaluated. We conclude that X-ray irradiation results in DNA lesions, ROS accumulation and?Ψ m decline in a dose-dependent manner, and that these changes may be one of causes of X-rays-induced apoptosis in yeast. Furthermore, yeast cell membrane integrity appeared compromised following irradiation,suggesting that membrane damage may also have a role in the biological effects of radiation.

Effects on Zinc Stress on Stress-Resistance Physiological and Biochemical Indexes of Jatropha curcas seedlings

Jatropha curcas seedlings were cultured for 21 d under 6 zinc concentrations of 0,25,50,100,200,400 mg/l to study the effects of ZnS O4 stress on the mechanism of resistance to heavy metal stress of J. curcas seedlings. The results showed that with the increase of stress concentration,the content of chlorophyll-a decreased and the activity of POD first increased and then maintained at a certain level or decreased slowly. The contents of soluble sugar,malondialdehyde,soluble protein and free proline increased,and the root activity increased first and then decreased. The relative conductivity of J. curcas seedlings decreased first and then increased,which indicated that the leaves of J. curcas seedlings had some adaptability and self-repairing capability under zinc toxicity stress,but the adaptability and self-repair ability were limited.

Grey Correlation Analysis of Physiological Traits Related to Drought Tolerance in Pennisetum sp.

The drought resistance of Pennisetum sp. was analyzed under different drought stress conditions simulated by various concentrations of PEG-6000. Changesofa series of indexes such as chlorophyll content, water content, relative electrical conductivity of osmotic solution, MDA content, proline content, soluble polysaccharide content and soluble protein content in the leaves were measured.The correlation of these indexes with the drought resistance of Pennisetum sp. was an- alyzed by the method of grey correlation analysis. The results showed that the chlorophyll, water content, relative electrical conductivity and soluble protein con- tentexhibited obvious negative correlation with the stress concentration, which de- creasedfollowing the increase of PEG-6000 concentration. The soluble polysaccha- ride contentshowed an increasing trend,the MDA content showed a rise at first fol- lowed by a declinetrend, while the prolinecontent was just opposite to MDA. The changes of the 3 indexes showed obvious positive correlation with thestress con- centration. The correlation of these indexes with the drought resistance of Pennise- tum sp. were ranked as follows： leaf water content （0.980 8）, chlorophyll content （0.967 9）, MDA content （0.876 0）, soluble polysaccharide content （0.839 5）, soluble protein content（0.827 5）, relative electrical conductivity of osmotic solution（0.670 8）, and proline content（0.571 3）.

Effects of silver nanoparticles on resistance characteristics of the wetland plant Typha orientalis in a hydroponic system

To probe the influence and the adverse-resistance characteristics of wetland plants in presence of silver nanoparticles (AgNPs), the changes in the physiological and biochemical characteristics (including the superoxide dismutase (SOD) activity, catalase (CAT) activity, peroxidase (POD) activity, soluble protein content, and chlorophyll content) of Typha orientalis exposed to different concentrations of AgNPs solutions (0, 0.1, 1, 20 and 40 mg/L) were explored. Meantime, the accumulation of silver content in these plants was revealed. The results show that under low concentrations of AgNPs, the SOD and POD activities in the leaves of Typha orientalis are strengthened to different degrees. However, high concentrations of AgNPs inhibit the activities of SOD and POD. Under the stress of different concentrations of AgNPs, the CAT activities are inhibited initially and later recovered to some extent. Under the stress of low concentrations of AgNPs, the soluble protein content in the leaves of Typha orientalis increases significantly, but decreases more significantly with increasing concentrations of AgNPs. Low concentrations of AgNPs promote chlorophyll synthesis in the leaves of Typha orientalis , but the chlorophyll content subsequently falls to pre-stress levels. In contrast, high concentrations of AgNPs cause a certain inhibition to generate chlorophyll. Meanwhile, the results show that the silver concentrations of plant tissues increase with the exposure of concentrations of AgNPs and they have a positive relationship with the exposure of concentrations of AgNPs.

Effect of High Temperature on Outcrossing Characteristics at the Fertility Sensitive Period of Photo-thermo Sensitive Genic Male Sterile (PTGMS) Rice Lines

Four sterile lines （Peiai64S, Y58S, Guangzhan 63-2S and H638S） and the restoring line R527 were used as materials. Five temperature gradients （24, 27, 30, 33 and 36 ℃ in artificial climate chamber） and the natural temperature （as control） were treated to the four sterile lines for 6 d in the fertility sensitive period of heading to flowering stage, respectively, to study the effects of temperature on physiological biochemical characteristics of young panicles and outcrossing characteristics. The results showed that the percentages of exerted stigma of Peiai 64S and Y58S were the highest at 27 ℃, which were 86.81% and 86.06%, respectively, while the percentages of exerted stigma of Guangzhan 63-2S and H638S were the highest at 24 ℃, which were 76.24% and 81.76%, respectively; the stigma viability of Peiai 64S, Y58S, Guangzhan 63-2S and H638S were the best at 24 ℃, which were 1.96, 2.12, 1.74 and 1.94, respectively; the outcrossing rates of Peiai 64S, Guangzhan 63-2S and H638S were the highest at 24 ℃, which were 58.87%, 54.22% and 50.50%, respectively, while the outcrossing rate of Y58S was the highest at 27 ℃, which was 58.96%; and the contents of peroxidase （POD） of the four sterile lines increased significantly at 33 ℃ compared with the control, while the contents of malondialdehyde （MDA） and proline increased significantly at 36 ℃ compared with the control. There were differences in temperature sensitivity between the male sterile lines, and the 24 ℃ treatment during the sensitive period was the best for the fertility sensitive period of Peiai 64S, while 27 ℃ was the best temperature for Y58S, Gangzhan 63-2S and H638S.

Isolation and Identification of a Flocculant Producing Strain TS-1

[Objective] The purpose was to select out and identify a flocculant producing strain which could produce high active flocculant.[Method] The strain producing high active flocculant was isolated out and purified through medium culture and the selected strain was identified through observing its culture characters and determining its physiological and biochemical property.[Result] Fourteen strains of bacteria with flocculant producing function were isolated from tested soil samples through isolation,purification and preliminary screening using dilution-spread plate method and plate streaking method.Five strains of flocculant producing bacteria showing higher flocculation activity were selected out after second screening and their flocculation rates were higher than 70%;the flocculation activity of one strain among them was still stable after multiple subculturings,its flocculation rate was always above 90% and it was marked as TS-1.TS-1 was encapsulated Gram-positive bacillus and there was no lipid in it,such as poly-β-hydroxybutyric acid.TS-1 was Bacillus amyloliquefaciens,so it was named Bacillus TS-1.[Conclusion] The strain selected out in this experiment could be used in the flocculation and biochemical treatment of wastewater from starch industry.

Acclimation and Tolerance Strategies of Rice under Drought Stress

Rice （Oryza sativa L.） is an important food crop and requires larger amount of water throughout its life cycle as compared to other crops. Hence, water related stress cause severe threat to rice production. Drought is a major challenge limiting rice production. It affects rice at morphological （reduced germination, plant height, plant biomass, number of tillers, various root and leaf traits）, physiological （reduced photosynthesis, transpiration, stomatal conductance, water use efficiency, relative water content, chlorophyll content, photosystem II activity, membrane stability, carbon isotope discrimination and abscisic acid content）, biochemical （accumulation of osmoprotectant like proline, sugars, polyamines and antioxidants） and molecular （altered expression of genes which encode transcription factors and defence related proteins） levels and thereby affects its yield. To facilitate the selection or development of drought tolerant rice varieties, a thorough understanding of the various mechanisms that govern the yield of rice under water stress condition is a prerequisite. Thus, this review is focused mainly on recent information about the effects of drought on rice, rice responses as well as adaptation mechanisms to drought stress.

Physiological Responses of Dendrobium officinale under Exposure to Cold Stress with Two Cultivars

This study aimed to explore the cold tolerance of two cultivars of Dendrobium officinale(MG1,MG2)grown in different regions of China.Under-2℃ incubation,cultivar MG1 remained active after 3 d,and continued to grow after returning to room temperature.However,MG2 could only maintain its activity after 2 d treatment at−2℃,and the seedlings died with the low temperature treatment time.Investigation of the characteristics of the plants grown in the south(Hangzhou)or north(Zhengzhou)of China indicated that the leaves of MG1 also had reduced stomatal density,the highest thickness,and a compact microstructure.The contents of proline and soluble sugars were higher in MG1 than those in MG2.The cultivar MG1 had higher SOD enzyme activity than MG2,while CAT and POD activities in samples from Zhengzhou were higher than those from Hangzhou.The contents of polysaccharides and alkaloids in stems of in MG1 were higher than those in MG2,while the content of flavonoids in the Zhengzhou samples was higher than that in the Hangzhou samples.In addition,plant heights,stem diameters,and chlorophyll content were higher in MG1.Overall,MG1 had better cold resistance than MG2.MG1 is a cold tolerant cultivar with thick leaves and reduced stomatal density,higher contents of soluble sugars,proline,CAT,POD,polysaccharides,flavonoids and alkaloids,which together make it more adaptable to low temperatures.Thus,the cultivar MG1,with its demonstrated cold tolerance,can accordingly be grown on a large scale in cold regions,thereby expanding the available planting area for this important traditional medicinal plant to meet the increasing commercial demand for it.

Isolation and identification of moderately thermophilic acidophilic iron-oxidizing bacterium and its bioleaching characterization

A moderately thermophilic acidophilic iron-oxidizing bacterium ZW-1 was isolated from Dexing mine, Jiangxi Province, China. The morphological, biochemical and physiological characteristics, 16S rRNA sequence and bioleaching characterization of strain ZW-1 were studied. The optimum growth temperature is 48 ℃, and the optimum initial pH is 1.9. The strain can grow autotrophically by using ferrous iron or elemental sulfur as sole energy sources. The strain is also able to grow heterotrophically by using peptone and yeast extract powder, but not glucose. The cell density of strain ZW-1 can reach up to 1.02×108 /mL with addition of 0.4 g/L peptone. A phylogenetic tree was constructed by comparing with the published 16S rRNA sequences of the relative bacteria species. In the phylogenetic tree, strain ZW-1 is closely relative to Sulfobacilus acidophilus with more than 99% sequence similarity. The results of bioleaching experiments indicate that the strain could oxidize Fe2+ efficiently, and the maximum oxidizing rate is 0.295 g/(L·h). It could tolerate high concentration of Fe3+ and Cu2+ (35 g/L and 25 g/L, respectively). After 20 d, 44.6% of copper is extracted from chalcopyrite by using strain ZW-1 as inocula.

Effects of Silicon on Physiology and Biochemistry of Dendrobium moniliforme Plantlets under Cold Stress

[ Objective] The study aimed to investigate the effects of silicon on physiology and biochemistry of Dendrobium moniliforme plantlets under low tempera- ture stress. [ Method ] By using Dendrobium monilforme as the experimental material, different concentrations of Na2SiO3 （0, O. 2, 0.4, 0.6, 0.8, 1.0, 5.0 and 10.0 mmol/L） was added to the basic medium[ 1/2MS ＋ 6-BA （0.1mg/L） ＋ NAA （ 1 mg/L） ＋ agar （7.2 g/L） ＋ sucrose （30 g/L） ] for tissue culture; af- ter hardening and transplanting, Dendrobium moniliforme plantlets were treated under low temperature stress at 4 ~C for 0, 24 and 48 h, in order to investigate the physiological response of Dendrobium ranniliforme leaves to different concentrations of Na2SiO3. [ Result] Under low temperature stress at 4℃, Dendrob/um mon//i- fortns leaves have certain osmotic regulation ability, and the three osmotic regulation substances show different variation trends at different stages. Appropriate con- centration of NshSiO3 can increase the contents of free proline, soluble sugar and soluble protein to varying degrees, reduce MDA content and further improve the cold resistance of Dendrobium moniliforme plantlets. The order of the effects of Na2SiO~ on various physiological indicators is ： free proline 〉 MDA 〉 soluble sugar （or soluble protein）. According to the correlation analysis among various physiological indicators, free proline, soluble sugar, soluble protein and MDA contents can all be used as reference indicators to identify the cold resistance of Dendrobium moniliforme. [ Conclusion] The addition of Na2SiO3 （0.4 retool/L） can moder- ately decrease the thermal energy for normal growth of Dendrobium moniliforme, which is conducive to reducing the cost of cultivation. Key words Na2SiO3 ;Dendrobium monlifforme;Low temperature stress;Physiological and biochemical characteristics

不同成熟期对花椰菜种子活力及相关生理生化指标的影响

花椰菜种子收获时常依据经验进行,易导致采收时期不当,对种子质量造成较大的影响。为研究花椰菜杂交种子成熟期与种子活力的关系,确定适宜的种子收获期,本研究以花椰菜品种瓯松60天为材料,分析了授粉后40、45、50、55、60、65 d不同成熟期种子物理性状、种子活力和抗氧化酶活性等指标变化。结果表明,随着种子成熟期延长,种子含水量、鲜种子千粒重呈降低趋势,种子浸泡液电导率和丙二醛(MDA)含量先降低后趋于稳定,规定水分千粒重、超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性、发芽率、发芽势、活力指数、苗高、根长先增加后趋于稳定。不同授粉后天数之间比较结果表明,授粉后55、60、65 d,活力指数、苗高和根长差异不显著,但均显著高于50 d;规定水分千粒重、SOD活性、POD活性、MDA含量、电导率在授粉后55 d趋于稳定。回归分析结果表明,活力指数与鲜种子千粒重、种子含水量、MDA含量、电导率显著(P<0.05)或极显著(P<0.01)线性负相关,与SOD和POD活性极显著线性正相关(P<0.01)。活力指数、SOD活性、POD活性、MDA含量、电导率与种子发育天数符合二项式函数变化:y_(活力指数)=-0.131x2+16.957x-344.480,y_(SOD活性)=-0.020x2+2.668x-10.420,y_(POD活性)=-0.112x2+14.417x-368.610,y_(MDA含量)=0.113x2-13.771x+433.780,y_(电导率)=0.088x2-10.319x+338.680,达显著或极显著水平,可用来预测不同发育天数种子的活力、保护酶清除活性氧自由基能力和细胞膜结构的完整性。综上,授粉后55 d,瓯松60天种子已达可采收程度,发芽率98%,规定水分千粒重4.364 g,种子活力和种子生理也趋于稳定,且对幼苗生长没有影响,还可降低种子易落粒损失风险。本研究结果为花椰菜杂交种子适时采收提供了理论依据。

NaCl胁迫下外源亚精胺对马铃薯幼苗生理特征的影响

【目的】研究NaCl胁迫下外源亚精胺(Spd)对马铃薯幼苗生理特征的影响,为新疆盐渍化区域马铃薯种植提供技术参考。【方法】以晋薯16号马铃薯幼苗为材料,采用不同浓度NaCl模拟盐胁迫处理,研究外源亚精胺Spd对马铃薯植株生长、叶片抗氧化酶活性、渗透调节物质含量的影响。【结果】盐胁迫抑制了马铃薯植株生长,使得超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)等酶促类抗氧化酶活性表现为低盐胁迫促进,高盐胁迫抑制;抗坏血酸(ASA)、谷胱甘肽(DSH)等非酶促类抗氧化酶含量均降低;脯氨酸、可溶性糖、氨基酸含量升高;外源亚精胺(Spd)通过提高叶绿素含量、根系活力,调节渗透调节物质含量,增强抗氧化酶活性等方式维持植物体的正常生理代谢功能。【结论】外源亚精胺(Spd)可提升马铃薯耐盐性,缓解盐胁迫对马铃薯植株的抑制作用,其中0.9 mmol/L Spd(S 3)浓度缓解效果最明显。

7.2%萎锈灵和40%拌种灵包衣对棉花幼苗冷胁迫生理生化特征的功效比较

【目的】研究比较具有活性结构相似的2种杀菌剂萎锈灵和拌种灵包衣棉种提高棉种适应冷胁迫能力功效,分析2种杀菌剂包衣提高棉花适应冷胁迫的能力差异,及其生理作用机制,为开发提高棉花适应冷胁迫能力的新产品提供理论依据。【方法】以新疆北疆棉区主栽品种新陆早50号为材料,以基础种衣剂包衣棉种为对照,将萎锈灵和拌种灵分别添加到基础种衣剂中分别制成7.2%萎锈灵和40%拌种灵的种衣剂进行包衣,采用人工模拟低温环境(4℃/16℃)进行低温胁迫处理,观测各包衣处理对低温条件下棉花萌发、幼苗生长情况和耐冷性的生理响应。【结果】与对照比较,萎锈灵和拌种灵包衣处理的发芽势分别增加9.67%和5.33%;发芽指数分别增加12.00%和6.00%,活力指数分别增加13.33%和6.67%,电导率REC分别增加-12.5%和-3.75%,可溶性蛋白SP含量分别增加11.00%和6.00%,超氧化物岐化酶SOD活性分别增加10.67%和6.67%,冷胁迫指数CI分别降低-10.67%和-5.33%,且差异均显著;棉苗CI与REC、SP、SOD等指标呈显著相关性;萎锈灵包衣处理提高棉花幼苗生长适应冷胁迫能力优于拌种灵。【结论】在冷胁迫下,萎锈灵和拌种灵包衣处理均对棉花种子萌发和幼苗的生理特征有一定影响,能促进萌发期种子内营养物质的转化与合成,提高种子活性,从而提高种子的发芽率,通过诱导棉花幼苗细胞内部酶的活性增强,清除幼苗体内活性氧自由基,加快丙二醛MDA含量的积累,保护幼苗细胞膜结构稳定性,从而提高棉苗适应冷胁迫的能力。2种药剂中,萎锈灵种衣剂诱导棉苗适应冷胁迫效果优于拌种灵。

千年桐雌雄植株花期生理生化差异分析

为揭示千年桐雌雄植株之间的差异,分别以处在花期的雌雄植株叶片为试材,采用乙醇浸提法、蒽酮比色法、福林试剂测定法、氮蓝四唑法、愈创木酚法、酶联免疫吸附法,比较测定叶片叶绿素、可溶性糖、总酚含量,超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性以及内源激素含量差异。结果表明,千年桐植株叶片叶绿素a、叶绿素b、叶绿素总量、可溶性糖、总酚的含量均表现为雌株高于雄株,但差异不显著(P>0.05)。雄株叶片过氧化物酶(POD)活性、ZR和IAA含量均显著高于雌株(P<0.05),这几个指标与千年桐性别关系密切。