黄瓜低温耐受性鉴定方法的初步研究

本试验系统比较了不同低温胁迫条件下,黄瓜种质芽期和苗期低温耐受性的鉴定方法。分别在13℃和15℃(26℃为对照)对15份种质种子进行芽期低温胁迫,以种子活力相关的发芽率、发芽势和发芽指数以及种芽生长量相关的胚根长度、种芽鲜质量和种芽干质量等6项指标进行低温耐受性的鉴定评价。结果表明,13℃适合用于极耐低温材料的筛选,15℃适宜作为大量黄瓜种质芽期低温耐受性鉴定评价的胁迫温度。以冷害指数和恢复指数为评价指标,利用6℃恒低温处理不同天数,对黄瓜二叶一心幼苗进行苗期低温耐受性鉴定评价,适宜胁迫时间为3~5d。在15℃/5℃变温条件下对黄瓜一叶一心幼苗进行苗期低温胁迫,适宜胁迫时间为9~15d。以恢复指数作为评价指标进行苗期低温耐受性鉴定,其胁迫时间应比以冷害指数为评价指标的处理时间缩短1~2d。     

砧用南瓜品种资源抗旱性鉴定

以14份砧用南瓜品种为材料,对发芽期(23%PEG-6000模拟干旱)和幼苗期(控制浇水量)进行干旱胁迫处理,采用非加权算术平均法(UPGMA)聚类分析方法分析各品种资源的抗旱性,并对适宜鉴定砧用南瓜抗旱性的形态指标进行筛选。通过测定发芽势、发芽率、活力指数、发芽指数、茎粗、株高、叶面积、鲜质量、干质量、干旱胁迫指数、壮苗指数等11个发芽期和幼苗期的性状指标,将14份砧用南瓜品种资源分为抗旱品种、较抗旱品种、干旱较敏感品种和干旱敏感品种4类。在发芽期和幼苗期均表现出较强抗旱性的品种为大维10号、佳合台木、金刚1号、昆仑、日本根力神、日本绿霸、日本强力士、神砧和胜利(白)等9个品种。种子相对发芽率、相对发芽势、相对发芽指数、相对活力指数以及相对株高可作为砧用南瓜品种抗旱性鉴定的可靠指标,相对干质量可作为砧用南瓜品种资源抗旱性鉴定的有益指标。综合分析14个品种的耐盐性、耐寒性、耐热性和抗旱性,发现日本绿霸和日本强力士的多重抗性较强,可作为黄瓜嫁接的优质砧木。     

茄子种质资源耐盐性鉴定及耐盐评价指标筛选

对190份茄子种质资源进行盐胁迫处理,利用盐害指数和叶绿素损失率鉴定茄子种质资源耐盐性。根据耐盐性鉴定结果,选择15份耐盐性不同的材料进一步进行芽期和苗期耐盐性鉴定,通过对芽期种子相对发芽率、相对发芽势,以及苗期盐害指数、脯氨酸含量和叶绿素含量的测定,筛选适合评价茄子耐盐性强弱的标准。结果显示,刺茄、蒜芥茄、马来亚茄、眉州墨茄和天津二苠茄等5个品种具有较强的耐盐性,除了盐害指数外,相对发芽率、脯氨酸相对增加量和叶绿素损失率也可作为重要的耐盐评价指标。     

番茄砧木耐热性评价及热胁迫生理响应研究

南方地区番茄在春延后栽培和秋提前栽培中易受异常高温的影响,采用耐热砧木进行嫁接栽培可以提高番茄的耐热性。为筛选耐热性强的番茄砧木种质资源,本试验对20份番茄砧木种质的种子和幼苗进行热胁迫处理,根据热害表型和幼苗生长生理指标评价砧木种质的耐热性。结果表明,热胁迫抑制番茄砧木种子萌发,随着温度升高,种子发芽率明显降低。34 ℃时,除N3外的砧木种质种子发芽率降至50%以下;37 ℃时种子发芽率均降至24%以下,40 ℃时种子发芽率均为0。亚高温(34 ℃/28 ℃)和高温(37 ℃/28 ℃)胁迫下,G3、N3、Q2均表现强耐高温(HR),A1、Q3、Q4、Q5、Y4表现中耐高温(MR)或耐高温(R)。幼苗热害指数与株高、叶片丙二醛(MDA)含量呈极显著正相关,与叶片SPAD值、茎粗、全株鲜质量、全株干质量、叶片游离脯氨酸含量呈显著或极显著负相关。利用以上7项生长生理指标,采用隶属函数值法对供试种质的耐热性进行综合评价,种质G3、N3、Q2的耐热性居前3位,与亚高温胁迫的幼苗热害指数排序一致。综上,种质 G3、N3、Q2强耐高温,可作为选育耐热番茄砧木的骨干材料。     

不同辣椒品种种子萌发期耐低温性的研究

为确立辣椒种子萌发期耐低温性鉴定的指标和条件,探讨低温对不同类型辣椒种子萌发的影响,本试验以不同的辣椒品种为材料,测定不同温度下种子的发芽率、发芽势、发芽指数以及这3项指标的相对值。结果表明,18℃培养下的相对发芽指数、14℃培养下的相对发芽率可作为辣椒种子萌发期耐低温性鉴定的指标,18℃可作为筛选耐低温品种的压力条件;早熟品种种子对低温的耐受性较中熟和中晚熟品种强;线椒品种种子对低温的耐受性较好,甜椒最弱。     

PEG模拟干旱胁迫下辣椒种子萌发特性及抗旱性评价

为探究干旱胁迫对辣椒种子萌发的影响,筛选出抗旱性强的辣椒品种,以12个辣椒品种为试验材料,采用0％、5％、10％、15％、20％的PEG-6000浓度处理,以种子萌发期相对发芽率、相对发芽势、相对发芽指数、相对活力指数、相对苗高和相对根长为抗旱性评价指标,利用平均隶属函数进行抗旱性强弱评价.试验筛选出丰源大螺、博辣8号...     

不同温度条件对豇豆和萝卜种子萌发的影响

研究了不同温度条件下豇豆和萝卜种子的萌发特性.结果表明,不同温度处理对豇豆和萝卜种子的发芽率、发芽势和发芽指数均产生了不同程度的影响.28℃和30℃下豇豆的发芽率、发芽势和发芽指数较高;虽然不同温度处理未对萝卜的发芽率和发芽势产生影响.但25℃,28℃和30℃下萝卜的发芽指数较高,有利于萝卜种子的萌发.     

不同温度处理对莴笋和萝卜种子萌发特性及抗氧化酶活性的影响

研究不同温度处理对莴笋和萝卜种子的萌发特性及抗氧化酶活性的影响.结果表明:不同温度处理对莴笋和萝卜种子的发芽率、发芽势和发芽指数均有不同程度的影响.18℃、22℃和25℃下莴笋的发芽率、发芽势和发芽指数较高;虽然不同温度处理未对萝卜的发芽率和发芽势产生影响,但25℃、28℃和30℃下萝卜的发芽指数较高,有利于种子萌发.综合抗氧化酶活性来看,22℃是莴笋种子的最佳发芽温度,而25℃是萝卜种子的最佳萌发温度(SOD和POD活性最高).     

45份辣椒种质发芽期和苗期的耐冷性评价

冷害是我国冬春季辣椒生产中主要的逆境因子,选用耐冷品种可有效抵御冷害。以45份辣椒地方品种和高代自交系为试验材料,分析低温胁迫下的种子发芽及苗期生长情况,筛选发芽期和苗期表现耐冷的种质材料。结果表明,45份辣椒种质的种子在15℃低温胁迫下,V06C0299、V06C0445、V06C01581、2019P162等25份种质的相对发芽率超过93.33%,V06C0299、V06C0445、V06C1581、GW464等13份种质的相对发芽势超过91.11%。选用10份种质进行苗期4℃低温胁迫处理,V06C01581的冷害指数最低为0.32,表现出较强的耐冷性。相关分析表明,相对发芽率、相对发芽势与冷害指数呈负相关,相关系数分别为-0.280、-0.327(P <0.05)。利用隶属函数法综合评价表明,V06C0299平均隶属函数值最大为0.89,表现为较强的耐冷能力。研究结果可为辣椒耐冷基因挖掘和耐冷品种选育提供基础。     

不同温度处理对萝卜种子萌发及抗氧化酶活性的影响

研究不同温度条件下萝卜种子的发芽特性及抗氧化酶活性的变化.结果表明:不同温度处理对萝卜种子的发芽率、发芽势均未产生显著性影响;而对发芽指数产生了显著性影响,25、28、30℃下的发芽指数较高,种子萌发较快.综合各项指标来看,25℃是萝卜种子的最佳萌发温度.     

Effects of radiation from 188Re on smooth muscle cell proliferation

AIM: Although endovascular radiotherapy inhibits neointimal hyperplasia, the exact alterations induced by β-particles irradiation remain to be elucidated. The objective of this study was to investigate the ability and the cellular mechanism of local β^-particles emission from ¹⁸⁸Re to inhibit vascular smooth muscle cells (SMCs). METHODS: The SMCs in vitro were irradiated by ¹⁸⁸Re with single doses of 2.6 Gy-25.8 Gy. The effects of β-particles on SMCs, such as effective irradiate doses, the period of inhibition for SMCs proliferation, the changes of cell proliferation rate and DNA synthesis rate, cell cycle progression and related gene expression, were investigated by cell count, [³H]-TdR incorporation, cell cycle progression analysis, cell viability and immunocytochemistry, respectivecy. RESULTS: β-particles irradiation with dose of 5.2 Gy could inhibit significantly SMCs proliferation. At dose of 20.6 Gy DNA synthesis inhibitory rate was 92%, SMCs proliferation rate was only 3%. Renoval of ¹⁸⁸Re did not abolish the inhibitory effects of β-particles on SMCs proliferation. The expression of P53 was up regulation and PCNA was down regulation after irradiation. CONCLUSION: β-particles from ¹⁸⁸ Re was significantly effective and permanent in inhibiting SMCs proliferation, and inhibitory effect was in dose-dependet manner ED50was 5 Gy, the best dose to inhibit SMCs proliferation was 20 Gy. β-particles irradiation induced SMCs to occur G₀/G₁ arrest, damaged the ability of SMCs reproliferation and led to cell clonogenic death. P53 and PCNA had regulatiory effects on SMCs proliferation after β-particles irradiation.     

多效唑对猕猴桃离体试管苗生长及内源激素的影响

多效唑（ＰＰ３３３）处理猕猴桃试管苗，降低了其生长强度；植株体内的ＧＡ３、ＩＡＡ和ＺＴ含量下降，ＡＢＡ的含量上升，乙烯释放率增加；并且能降低外源的ＧＡ３和ＩＡＡ促进生长的作用，而外源的ＧＡ３和ＩＡＡ又能不同程度地逆转多效唑的抑制作用，使植株恢复生长。     

Proteomic analysis between pathological scars and normal skin

AIM: To investigate and screen the sensitive proteins in the formation mechanism of pathological scars by comparing the results of differential proteomic analysis between pathological scars and normal skin.METHODS: Two-dimensional gel electrophoresis was used to detect the protein expression profiles in 8 keloid patients, 8 hypertrophic scar patients and 3 matched normal skin patients.The proteins that showed differential expression of over 4-fold change were cut and analyzed by MALDI-TOF/TOF mass spectrometry.RESULTS: A two-dimensional protein profiling comparison between pathological scars and normal skin was successfully established.On average, 2 978 spots in keloid, 2 975 spots in hypertrophic scar and 3 053 spots in normal skin were identified using gel analysis software.Compared with normal skin, there were totally 36 differentially-expressed proteins in keloid and hypertrophic scar identified from the spots of over 4-fold change, including 16 proteins in both keloid and hypertrophic scar (8 up-regulated and 8 down-regulated), 11 only in keloid (9 up-regulated and 2 down-regulated) and 9 only in hypertrophic scar (4 up-regulated and 5 down-regulated).CONCLUSION: Proteomic analysis can identify the proteins with variance of pathological scars versus normal skin, thus providing probable new clues to reveal the formation mechanism of pathological scars.     

Coupling past management practice and historic landscape change on John F. Kennedy Space Center,Florida

Historic landcover dynamics in a scrubby flatwoods (Tel-4) and scrub landscape (Happy Creek) on John F. Kennedy Space Center were measured using aerial images from 1943, 1951, 1958, 1969, 1979, and 1989. Landcover categories were mapped, digitized, geometrically registered, and overlaid in ARC/INFO. Both study sites have been influenced by various land use histories, including periods of range management, fire suppression, and fire management. Several analyses were performed to help understand the effects of past land management on the amount and spatial distribution of landcover within the study sites. A chi-squared analysis showed a significant difference between the frequency of landcover occurrence and management period. Markov chain models were used to project observed changes over a 100-year period; these showed current management practices being effective at Tel-4 (restoring historic landscape structure) and much less effective at Happy Creek. Documenting impacts of past management regimes on landcover has provided important insight into current landscape composition and will provide the basis for improving land management on Kennedy Space Center and elsewhere.     

XBP-01 accelerated apoptosis induced by oxidized low density lipoprotein in vascular smooth muscle cells

AIM: Previous studies performed with XBP-01 in vitro indicated that XBP-01 could inhibit vascular smooth muscle cells from being transformed into foam cell and could eliminate the atherosclerotic plaque in C57BL/6J mouse. This experiment is to investigate its mechanism of eliminating plaques in vitro. METHODS: The cultured porcine artery smooth muscle cells incubated with XBP-01 of 0.1 mg/L for 24 h after preincubated with oxidized low density lipoprotein of 15 mg/L for 72 h in vitro. The samples were analyzed by fluorescence microscope, confocal microscope system and flow cytometry. RESULTS: Apoptosis was triggered by being incubated with oxidized low density lipoprotein and this process was accelerated additionally by being incubated with XBP-01. CONCLUSION: XBP-01 can be effective in eliminating atherosclerotic plaque by accelerating the process in which oxidized low density lipoprotein induced smooth muscle cell apoptosis.     

The effect of exposure on landscape scale soil surface temperatures and species distribution models

Species distribution models (SDMs) often use elevation as a surrogate for temperature or utilise elevation sensitive interpolations from weather stations. These methods may be unsuitable at the landscape scale, especially where there are sparse weather stations, dramatic variations in exposure or low elevational ranges. The goal of this study was to determine whether radiation, moisture or a novel estimate of exposure could improve temperature estimates and SDMs for vegetation on the Illawarra Escarpment, near Sydney, Australia. Forty temperature sensors were placed on the soil surface of an approximately 12,000 ha study site between November 2004 and August 2006. Linear regression was used to determine the relationship with environmental factors. Elevation was correlated more with moderate temperatures (winter maximums, summer minimums, spring and autumn averages) than extreme temperatures (summer maximums, winter minimums). The correlation (r ²) between temperature and environmental factors was improved by up to 0.38 by incorporating exposure, moisture and radiation in the regressions. Summer maximums and winter minimums were predominately determined by exposure to the NW and coastal influences respectively, while exposure to the NE and SW was important during other seasons. These directions correspond with the winds that are most influential in the study area. The improved temperature estimates were used in Generalised Additive Models for 37 plant species. The deviance explained by most models was increased relative to elevation, especially for moist rainforest species. It was concluded that improving the accuracy of seasonal temperature estimates could improve our ability to explain the patchy distribution of many species. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Expression and significance of c-IAP2 and GAS1 in Hodgkin's lymphoma and anaplastic large cell lymphoma

AIM: To detect the expression of cytoplasmic inhibitor of apoptosis protein 2 (c-IAP2) and growth arrest-specific gene 1 (GAS1) in Hodgkin's lymphoma (HL) and anaplastic large cell lymphoma (ALCL) and to investigate the role of two genes in the pathogenesis of HL and ALCL.METHODS: HE staining, the antibodies CD30, CD15, CD45RO and CD20 were used to screen the cases of HL and ALCL from 288 cases of lymphoma. The clarified HL and ALCL were subjected for immunohistochemical staining by SP and ABC methods to analyze the expression of c-IAP2 and GAS1. RESULTS: ①The positive rate of c-IAP2 in HL was 25/26(96.1%) while that in ALCL was 6/19(31.6%), there presented statistic significance between HL and ALCL groups(P<0.05), meanwhile the positive rate of GAS1 showed statistic significance between HL and ALCL groups(P<0.05). ②Two cases were showed to be a mixed type combined with large tumor cells of HL and relatively smaller tumor cells of ALCL.CONCLUSION: ①The different expression of c-IAP2 and GAS1 in HL and ALCL implied a different mechanism of oncogenesis and the different defects in the pathway of signal transduction of apoptosis in HL and ALCL;②Few cases showed an overlap and a likely transitional state between HL and ALCL; ③The different expressing manner of GAS1 and c-IAP2 in HL and ALCL implied the potential marks for the differential dignosis of two kinds of lymphoma.     

Effects of patch attributes, barriers, and distance between patches on the distribution of a rock-dwelling rodent (Lagidium viscacia)

We tested whether size of habitat patches and distance between patches are sufficient to predict the distribution of the mountain vizcacha Lagidium viscacia a large, rock-dwelling rodent of the Patagonian steppe Argentina, or whether information on other patch and landscape characteristics also is required. A logistic regression model including the distance between rock crevices and depth of crevices, distance between a patch and the nearest occupied patch, and whether or not there was a river separating it from the nearest occupied patch was a better predictor of patch occupancy by mountain vizcachas than was a model based only on patch size and distance between patches. Our results indicate that a simple metapopulation analysis based on size of habitat patches and distance between patches may not provide an accurate representation of regional population dynamics if patches vary in habitat quality independently of patch size and features in the matrix alter connectivity. This revised version was published online in August 2006 with corrections to the Cover Date.     

Inhibitory β-adrenergic receptor in heart

β₃-adrenergic receptor is the third subtype of β-adrenergic receptors. The genetic structure and pharmacological property of β₃-adrenergic receptor are markedly distinguished from β₁-and β₂-adrenergic receptor subtypes. Recently studies show that myocardial β₃-adrenergic receptor mediates negative inotropic effect through Gi-protein/NO/cGMP pathway, the expression of β₃-adrenergic receptor and negative inotropic effect mediated by β₃-adrenergic receptor are increased in heart failure. However, because of the low expression of β₃-adrenergic receptor in the heart, the actual pathophysiological significance of β₃-adrenergic receptor remains unknown.