水杨酸对小麦镉毒害的缓解效应

研究了外源水杨酸(SA)对小麦镉(Cd)毒害的缓解效应.结果表明,低浓度(0.5 mmol/L 以下)SA能够促进扬麦158种子萌发及幼苗生长,高浓度则有抑制作用.0.5 mmol/L SA浸种能够明显缓解0.1 mmol/L、0.5 mmol/L Cd对小麦种子萌发及幼苗生长的抑制,能提高根中超氧化物岐化酶(SOD)和过氧化物酶(POD)酶活性,但不能减轻1.0 mmol/L Cd对小麦种子萌发及幼苗生长的抑制.     

外源水杨酸对镉毒害下莴苣种子萌发的缓解效应

重金属Cd作为毒性较高的环境毒物,不仅危害植物的生长和发育,也对人类健康带来严重威胁.水杨酸(Salicylic acid,SA)作为一类新型植物生长调节物质,在诱导植物抗性方面起重要调节作用.以莴苣笋王一号为试验材料,研究了不同浓度SA处理对cd胁迫下莴苣种子萌发的效应及其生理机制.结果表明,Cd胁迫条件下,莴苣种子萌发受到影响,表现为发芽势、发芽指数、活力指数和根长明显降低.Cd胁迫还可引起氧化胁迫产生,并造成膜脂过氧化伤害.不同浓度SA对Cd胁迫下莴苣种子萌发和幼苗生长的缓解作用不同,表现为低促高抑效应;以0.1mmol/L的SA效果最好.SA处理能缓解Cd对种子萌发和幼苗生长的伤害与植株体内CAT、APX、SOD和GPX等抗氧化酶活性变化有关.     

水杨酸对缓解葡萄苗铝毒害的生理机制

为了探明水杨酸对缓解葡萄苗铝毒害的生理机制,解决葡萄在酸性土壤中发生铝毒害的问题。以水晶葡萄为材料,采用水培的方法,在培养液中加入0.4 mmol/L氯化铝和不同浓度的水杨酸共培养5周,之后测定葡萄根系、茎干和叶片的生长状况、叶绿素含量、叶片和根系的活性氧清除系统及膜脂过氧化等指标,分析铝胁迫下水杨酸对葡萄苗生长及生理的影响。结果表明,铝胁迫下,葡萄植株生长受抑,嫩叶黄化,根系变黑;老叶叶绿素含量上升,嫩叶叶绿素含量下降;叶片和根系的SOD、POD活性和MDA含量上升,氧自由基产生速率也上升,而根系活力则下降。25,50μmol/L水杨酸处理明显促进了葡萄苗枝干的生长,根系颜色为微红色,但100μmol/L水杨酸处理却明显抑制了葡萄苗的生长,有少量根系变黑。水杨酸处理对葡萄苗缓解铝毒害的生理效应明显,25和50μmol/L水杨酸使老叶叶绿素和类胡萝卜素含量显著高于CK和单独铝胁迫,使嫩叶叶绿素a、叶绿素a+b和类胡萝卜素含量比单独铝处理显著升高,水杨酸处理使叶片的SOD、POD活性和根系的SOD活性低于单独铝处理,而根系POD活性显著高于单独铝处理,叶片和根系氧自由基产生速率和丙二醛含量比单独铝处理有所下降;此外,50μmol/L水杨酸处理还显著提高了铝胁迫下的根系活力。可见,铝胁迫对葡萄植株生长的抑制作用明显,表现出较大的毒害作用,而水杨酸处理对缓解葡萄铝毒害具有一定的效果,其中以50μmol/L水杨酸处理对缓解葡萄苗铝毒害的生理效应最明显。     

外源水杨酸对白菜种子铬毒害的缓解效应

以白菜种子为材料,研究不同浓度Cr^6＋毒害条件下外施水杨酸对白菜种子萌发和幼苗生长的缓解效应。结果表明：在Cr^6＋毒害处理组中．白菜种子的发芽和幼苗生长随Cr^6＋处理浓度的增加而受到抑制．在Cr^6＋毒害条件下．外施0．1mmol／L水杨酸处理组与Cr^6＋毒害处理组相对照．水杨酸处理组明显提高了白菜种子的发芽指数、活力指数．苗鲜重与幼苗叶绿素含量,主根和侧根的生长抑制得到缓解．能够明显缓解低浓度Cr^6＋（0．05mmol／L以下）对白菜种子萌发及幼苗生长的抑制。因此可以推断出：水杨酸对白菜种子在Cr^6＋毒害条件下的发芽率和发芽势的缓解效果不明显,而对白菜种子发芽指数、活力指数、幼苗的鲜重、株高、主根长、侧根数和叶绿素a,b的含量有促进作用,效果显著：水杨酸缓解处理提高了种子活力．促进了幼苗生长。     

硅对水稻生长的影响及其缓解镉毒害机理研究进展

为研发高效硅肥和防治农田镉污染提供借鉴资料,本文综述了施加硅肥对水稻生长发育的影响,包括提高水稻产量和品质,增强抗倒伏、抗病虫害及干旱等逆境的能力,尤其是增强抗镉毒害等能力。并从生理学机制和土壤学机制两方面重点分析了施加硅肥对缓解镉毒害作用的可能机理。生理学机制方面:硅通过参与水稻的生理代谢活动,使水稻抗氧化系统酶的活性和清除自由基的能力增强;抑制镉的吸收及其在水稻体内的运输;硅与镉在水稻体内的螯合和区隔作用。土壤学机制方面:硅肥改变土壤理化性质,降低土壤中有效态镉的含量;硅镉吸附沉淀作用,减少水稻对镉吸收。最后针对硅肥的开发利用及技术推广提出展望。     

生物炭对酸化土壤锰毒害的缓解效应研究

生长在酸性土壤上的植物受一系列障碍因素的影响,其中锰毒是继铝毒之后限制植物生长的第二重要因素。本研究旨在利用生物炭改良酸化土壤的同时进一步缓解土壤锰的毒害效应。通过1个月的室内培养试验,研究在酸化土壤中和在酸化土壤施加外源锰(2、4 mmol/kg)两种情况下,分别添加3%的两种不同生物炭──稻壳炭和苹果枝条炭,对空心菜生长和锰毒害的影响。结果表明：（1）在酸化土壤中,添加两种不同生物炭均可显著增加空心菜的株高和生物量;在酸化土壤施加外源锰条件下,空心菜的株高和生物量显著受到抑制,添加稻壳炭能够显著缓解锰对空心菜生长的抑制作用,但苹果枝条炭不能有效缓解锰对空心菜的生长抑制;在高锰(4 mmol/kg)抑制条件下,空心菜植株出现生理缺水,两种生物炭的添加均能显著缓解空心菜植株的缺水现象。（2）生物炭的添加显著提高了土壤pH值,土壤pH值的变化与空心菜株高和生物量变化呈显著或极显著性相关。（3）添加稻壳炭和苹果枝条炭使空心菜对锰的累积浓度分别减少了48.5%和26.6%;外源锰施加情况下,空心菜对锰元素的富集浓度达到1502.1~2185.9 mg/kg,稻壳炭的添加使空心菜对锰的累积显著降低到516.4~975.5 mg/kg,但苹果枝条炭无法有效缓解外源锰对空心菜的毒害。（4）两种生物炭尤其稻壳炭可有效或显著降低土壤交换性锰含量,增加土壤易还原性锰含量,但未对土壤活性锰总量产生显著性影响。稻壳炭和苹果枝条炭能够显著促进空心菜生长、改善外源锰毒对植株造成的缺水现象;两种生物炭均能显著降低空心菜对锰的累积,提升土壤pH值、减少土壤交换性锰含量,不同程度缓解锰的毒害并促进植物生长。     

水杨酸对铅胁迫下玉米幼苗生长的缓解作用初探

应用土培法盆栽试验,研究不同浓度水杨酸对铅胁迫下玉米幼苗生长的缓解作用.结果表明:铅胁迫下玉米幼苗叶绿素和蛋白质含量降低,脯氨酸和MDA含量增加;在一定浓度范围内,SA对铅胁迫下的玉米幼苗生长具有一定的缓解作用,水杨酸处理使玉米幼苗叶绿素和蛋白质含量上升,而脯氨酸和MDA的含量减少.在5~20mg/L SA范围内,随浓度升高,缓解效应越明显.     

外源有机酸对小麦铝毒害的缓解效应

研究了在铝胁迫的条件下,加入外源有机酸对小麦铝毒害的缓解效应.结果表明,加入外源柠檬酸和苹果酸均能够明显减轻铝对小麦生长的抑制效应,减少对铝的吸收,促进对钙的吸收,柠檬酸的作用更为明显.     

边缘细胞对大豆根尖铝毒害的缓解

以大豆[Glycine max (L.) Merrill]浙春3号为试验材料, 采用静置培养(保持边缘细胞附于根尖)和振荡培养(移除根尖边缘细胞), 测定边缘细胞数目和活性、根相对伸长率和根内酶的活性, 研究了边缘细胞对大豆根尖铝毒害的缓解效应。结果显示, 大豆发育过程中存活的边缘细胞数与总数之比达60%~80%, 50~400 mmol L^-1 Al³⁺胁迫12 h能诱导边缘细胞从根尖脱落, 200~400 μmol L^-1 Al³⁺胁迫24 h对边缘细胞的发育有抑制作用。Al³⁺处理抑制根伸长, 移除边缘细胞的根相对伸长率低于保留边缘细胞的根。0~100 mmol L^-1 Al³⁺胁迫12 h, 0和50 mmol L^-1Al³⁺胁迫24 h, 具有边缘细胞的大豆根系的POD、SOD活性及蛋白质含量显著高于移除边缘细胞的根内酶活性和蛋白质含量, 但200和400 mmol L^-1 Al³⁺处理12 h, 100~400 mmol L^-1 Al³⁺处理24 h时, 根尖有无边缘细胞对根系的酶活性及蛋白质含量影响不显著。说明低浓度Al³⁺胁迫下, 大豆通过增加边缘细胞数目、提高根尖蛋白质含量, 维持较高水平的POD、CAT和SOD活性来对抗铝毒胁迫, 以缓解植物的铝毒害。     

两个黑麦草品种对镉吸收富集比较研究

采用盆栽试验研究比较两个黑麦草品种在不同Cd污染水平(0、75、150、300及600 mg.kg-1)下生长量、抗氧化酶活性、Cd含量及积累量的差异,以筛选出更适合作为土壤镉污染修复的品种。结果表明,随着土壤镉水平的增加,两个黑麦草品种根系干重、阿伯德地上部干重和植株总干重呈先增加后降低的趋势。土壤镉污染水平为75 mg.kg-1时,阿伯德地上部和植株总干重达到最大值(10.92 g.pot-1和12.03 g.pot-1),较对照分别增加了11.13%和10.67%。两个黑麦草品种各部位SOD活性、CAT活性和根系POD活性,均随土壤镉水平的增加呈先升高后降低的趋势,地上部MDA含量则逐渐升高。两个黑麦草品种镉转运系数、镉富集系数均大于1。黑麦草对Cd耐性和吸收富集存在基因型差异。比较两个品种黑麦草,在75~600 mg.kg-1Cd胁迫下,阿伯德品种地上部干重和总干重均高于邦德品种,且阿伯德地上部和根系镉含量及镉积累量高于邦德。阿伯德更适合作为土壤镉污染的植物修复材料。     

草地早熟禾对多年生黑麦草种苗化感影响的研究

以草地早熟禾8个品种为供体,按照培养皿生物检测方法,研究其浓度为10%的茎液浸提液对多年生黑麦草两个品种的种子萌发和幼苗生长的化感效应。结果表明,草地早熟禾茎叶浸提液对多年生黑麦草的发芽率、根长、苗长及幼苗鲜重等均存在化感作用的潜势,其中肯塔基对多年生黑麦草的化感抑制最强,普拉蒂尼对荣誉种子萌发、公园对荣誉的幼苗生长的化感抑制也较明显。     

利用流式细胞术鉴定黑麦草倍性方法的研究

为了测定几种不同倍性的黑麦草核DNA含量,利用流式细胞术（Flow Cytometry,FCM）检测黑麦草的染色体倍性,并通过传统的染色体制片的方法对其结果进行验证。结果表明不同品种间细胞核DNA含量差异显著,且随着倍性水平的增加,细胞核DNA相对含量随之成倍增加。流式细胞术检测结果与染色体制片检测结果一致。利用流式细胞仪测定黑麦草核DNA含量,具有样品制备简单,测量快速,精度高等优点,是进行倍性鉴定的理想方法。     

可降解络合剂对黑麦草种子萌发和幼苗生长的影响

以黑麦草为实验材料,研究了土壤中添加不同浓度(0,3,6,9,12,15 mmol/kg)生物可降解络合剂谷氨酸二乙酸四钠(GLDA)和亚氨基二琥珀酸四钠盐(IDS)对种子萌发和幼苗生长的影响,旨在找到2种络合剂应用的适宜浓度.结果表明,添加络合剂GLDA和IDS对黑麦草的种子萌发有一定的抑制作用,并且高浓度的处理抑制作用更为显著;而对黑麦草的地上生长表现为低浓度促进、高浓度抑制.在整个生长期,络合剂均抑制了黑麦草的根系生长.当络合剂GLDA和IDS浓度为9 mmol/kg时,黑麦草叶绿素含量最高,较对照提高了39.85％和47.18％;当GLDA和IDS浓度为6 mmol/kg时,类胡萝卜紊含量最高.隶属函数综合分析表明,络合剂对黑麦草种子萌发和幼苗生长影响最大的浓度为15 mmol/kg的处理,以络合剂IDS浓度为6 mmol/kg的处理生长状况最佳.     

Comparison of Progeny-Testing Methods in Lolium perenne L.

From 28 genotypes, half-sib families were generated by polycross (PX) and 2 topcrosses (TC). TC-testers were partially inbred cms-lines. Progenies were tested for annual dry matter yield in 3 successive years. The three year average was 80.7, 76.6 and 74.0 dt/ha for TC 1, PX and TC 2, respectively. TC 1 had the highest yielding families and the largest mean in all years. TC 2 revealed the largest range among its families. Genetic variance was highest for TC 2 with 14.02, followed by TC 1 and PX with 12.05 and 10.92. However, genotype × year interaction variance was about 2 and 4 times greater for TC 1 and TC 2 as compared to PX. Genetic correlation between testcross progenies was tightest for PX vs. TC 1 (rg = 0.644⁺⁺), while between the two TC's only rg = 0.307⁺ was observed. Predicted response to selection yielded very similar results for all test-crosses.     

Isozyme and quantitative traits polymorphisms in European provenances of perennial ryegrass (Lolium perenne L)

Twenty populations of Lolium perenne originating from a range of habitats in Europe were compared for isoenzyme polymorphisms and agronomically important quantitative traits in order to establish relationships of the levels of diversity with the origin of each population and to assess their suitability to be included in the European core collection of Lolium germplasm. Forty genotypes from each of the twenty populations and each genotype represented by three clonal propagules, were field planted in a fully randomized spaced plant design and fifteen quantitative characters including yield, persistency, reproductive and disease resistence characters were evaluated over a period of two years. Seven putative isozyme loci were assayed to compare the allozyme divergence of populations. The results of the isozyme survey indicate that 71–100% of the loci were polymorphic, 2.3–3.0 alleles/locus and the gene diversity was varying from 0.234–0.410. Of the total allelic diversity 94% remained within populations (H_s) whilst only 6% was distributed among populations (D_st). The differences between populations were determined on the basis of allele frequencies and multivariate analyses of quantitative characters. Populations significantly differed in their allele frequencies at all loci analysed. Random mating was predominant in all populations at most of the loci. The study revealed that the German accession BA 10998 was clearly distinct from the rest both in quantitative characters and allele frequencies. German accession BA 11015 with the lowest gene diversity showed the highest genetic variation for quantitative characters. However, no strict relationship was found between the genetic distance and the geograpical distribution of the populations. Among the quantitative characters, flowering time showed a strong relationship with the type of management practised at the collection site than their place of origin. This revised version was published online in July 2006 with corrections to the Cover Date.     

Segregation of Isozyme Marker Loci Amongst Androgenetic Plants of Lolium perenne L.

The segregation of isozyme markers has been examined in the green and albino androgentic progenies of two plants of Lolium perenne. Overall the pooled data for the loci PG1/2 and GOT/2 does not deviate from expectation, but there is considerable heterogeneity between families and between green and albino plants. Specific alleles predominate in the different progeny sets. The results may be accounted for by possible linked loci affecting anther culture response or of linked lethal genes.     

Genetic Variation for Seed Yield in Perennial Ryegrass (Lolium perenne L.)

In perennial ryegrass seed yield is low and unreliable and little is known about the seed-yielding capacity of different cultivars. Therefore, genetic variation for seed yield was studied for therefore, genetic variation for seed yield was studied for three years at two locations. Twelve trials consisting of drilled plots of nine diploid, late-flowering cultivars in four replications were harvested for seed. Significant gentic differences for seed yield and seed weight weight were detected. The ranking of the cultivars for seed yield differed from that for seed weight. The levels of seed yield and seed weight were affected by such environmental factors as year, soil type and crop production year, but interactions of these factors with cultivars were generally not significant. Variation in seed yield was more related to variation in seed number than to variation in seed weight. There were no significant cultivar differences for yield stability. The highest yielding cultivar was superior over a wide range of environments and the seed yield of the poorest cultivar was on average only 64% of that of the best cultivar.     

Comparison of Progeny-Testing Methods in Lolium perenne L.

From 22 genotypes, selfed (S₁) and testcross progenies were investigated. The latter were generated by i) polycross (PX) and ii) 2 topcrosscs (TC) using cms-inbred lines as a tester. Progenies were tested for annual dry matter yield in 3 successive years, the 3-year average was 76.7 dt/ha for S, and 76.9, 80.1 and 74.5 for PX, TC 1 and TC 2, respectively. Genetic variance was highest for S₁ (20.42), while the average of the 3 tcstcrosses was 12.22. However, the genotype-year interaction variance of S, Was 52.21, being 2–3 times greater than for the 2 topcrosscs. PX progenies were the most stable across years. Predicted response to selection was highest for S₁ (10.4 %). Genetic correlation (r_g) between S₁ and the testcrosses was highest with TC 2 (r_g= 0.5931⁴⁴).     

Sortenbedingte Reaktion bei Lolium perenne L. auf systemisch selektiv wirkende Herbizide

Variety-specific reaction of Lolium perenne L. on selective systemic herbicides
The investigation intended to show the specific reaction of different varieties of Lolium perenne on selective systemic herbicides. These results can be regarded as the base for advanced explorations to the described topic. The results may be summarized as follows:
Independent of the stage of growth, the date of application, the dosage and the droplet size there were effects on the forage yield in correlation to the variety and the active ingredient. Measurable yield reductions were presented after CMPP application on the varieties of the late and after the treatment with Asulam on the varieties of the early maturity group. Compared to the maturity group the varietal attribute growthhabit demonstrated no significant effects. The active ingredients MCPB and MCPA presented not any measurable influence on the forage yield of the different varieties. In the main harvest year the yield depressions were manifested clearer than in the seeding year. In the same way the described secondary actions were larger after the treatment in an advanced stage.
Extended investigations should inquire to the causes and secondary effects on the forage quality. Beyond this for variety testings of species with a large distribution and volume it seems remunerative to include questions of herbicides tolerance.     

植物生长调节剂对黑麦草种子萌发和幼苗生长的影响

利用植物生长延缓剂PP333、B9处理黑麦草（Lolium perenne L.）种子，研究其对种子萌发和幼苗生长的影响。结果表明：二者均可以在不影响发芽率的前提下，有效控制黑麦草苗期的高生长，但B9的抑制效果要显著强于PP333。PP333的最佳浸种浓度为750mg/kg;B9的最佳浸种浓度为3000mg/kg。最佳的浸种时间为8h。