高温胁迫对甜椒光合作用和叶绿素荧光的影响

 研究了35、40、45 和50 ℃高温处理0～60min 对甜椒净光合速率(Pn) 、细胞间隙CO₂ 浓度(Ci) 、气孔导度(Gs) 、蒸腾速率(Tr) 以及叶绿素荧光参数的影响。结果表明,35 和40 ℃处理下, Pn 随Ci 的下降而下降, 而45 和50 ℃处理下, Pn 明显下降, 但Ci 在45 ℃下变化不大, 50 ℃下增加, Gs 的变化与Tr 呈显著正相关。表明在严重的高温胁迫下光合抑制主要是由于非气孔限制引起, 而在胁迫较轻时, 可能主要是通过气孔限制。蒸腾作用对气孔导度的敏感性高于光合作用。叶绿素荧光参数Fv/ Fm、Fm、Fo 在35 和40 ℃处理下变化不大,而45 和50 ℃处理下Fv/ Fm、Fm明显下降, 但Fo 上升, 处理结束后置于25 ℃下24 h 后都能得到恢复, 表明短期高温下光系统II 的可逆性失活是光抑制的主要原因。     

外源茉莉酸甲酯对干旱胁迫下萱草光合生理的缓解效应

以萱草"红运"为试材,采用PEG模拟干旱胁迫的方法,研究了干旱胁迫对萱草光合生理的影响以及外源MeJA对干旱胁迫下萱草光合生理的缓解效应,以期为提高外源茉莉酸甲酯(MeJA)在萱草园林绿化抗旱栽培中的合理利用提供参考依据.结果表明:干旱胁迫显著降低了萱草叶片光合色素含量及气孔导度(Gs)、蒸腾速率(Tr)和胞间CO2浓度(Ci),提高了 PSⅡ初始荧光(Fo)和非光化学淬灭系数(NPQ),而最大荧光(Fm)、PSⅡ潜在活性(Fv/Fo)、最大光化学效率(Fv/Fm)、实际光化学效率(ΦPS Ⅱ)、光化学淬灭系数(qP)等受到显著抑制,最终表现为光合速率(Pn)降低.干旱胁迫下外源MeJA显著增加了光合色素的含量,在一定程度上可通过减少叶绿素的分解和提高叶片光合机构的稳定性来减轻干旱胁迫对萱草的伤害,且叶片Gs、Ci、Pn、Fm、Fv/Fo、Fv/Fm、ΦPSⅡ、qP均比干旱胁迫下有所增大,Fo和NPQ降低,而茉莉酸代谢抑制剂(SHAM)处理逆转了干旱胁迫下MeJA对萱草叶片光合特性的影响,表明在干旱胁迫下,外施MeJA可以减轻干旱胁迫下光合系统发生的光抑制现象,缓解干旱胁迫对萱草叶片光合机构的损伤以及PSⅡ反应中心的伤害,改善电子传递速率和光能转换效率,从而增强叶片的气孔导度和光合能力,增加光合产物的积累,提高萱草的抗旱性.     

外源多胺对低温胁迫下黄瓜幼苗叶绿素荧光参数的影响

应用外源多胺(Polyamines,PAs)腐胺(Putrescine,Put)、亚精胺(Spermidine,Spd)、精胺(Spermine,Spm)处理2叶1心黄瓜幼苗,然后进行8℃/8℃低温及恢复处理,研究Put、Spd、Spm对黄瓜幼苗叶绿素荧光参数的影响。结果表明,在低温胁迫下黄瓜幼苗叶片叶绿素荧光参数最大荧光Fm、最大光化学效率Fv/Fm、PSII(光系统II)潜在活性Fv/F0均下降,初始荧光F0上升,表明PSII受到了伤害,使得PSII原初光能转换效率、PS潜在活性降低;与单纯低温胁迫相比,外源Put、Spd、Spm预处理均可以提高Fm、Fv/Fm、Fv/F0,而使F0降低。这一结果从叶绿素荧光动力学方面说明Put、Spd、Spm对改善黄瓜的耐冷性有一定的作用。     

两种盐胁迫对苦楝幼苗光合特性的影响

以一年生苦楝实生苗为试材,采用温室盆栽方式,用浓度为0%(CK)、0.2%、0.4%与0.6%的Na2SO4和Na2CO3溶液分别对幼苗进行胁迫处理21 d,比较了2种盐胁迫下幼苗光合作用和叶绿素荧光参数的变化和差异。结果表明:0.2%盐浓度对Pn、Tr、Ci、Fv/Fm、Fv/Fo、qP和NPQ没有显著影响,0.6%盐浓度则影响显著。同时,各浓度盐处理对Chl a、Chl b、Chl(a+b)、Chl a/b、Fo和Fm没有显著影响。2种盐处理对苦楝幼苗叶绿素含量没有显著影响;Na2CO3胁迫通过非气孔限制引起Pn下降,而Na2SO4引起Pn下降分别为0.2%处理时是气孔限制,0.4%和0.6%处理时是非气孔限制;幼苗光合作用和光合机构对0.2%浓度胁迫有较强耐性,对0.6%浓度胁迫耐性较弱;同时,碱性盐Na2CO3胁迫对苦楝光合作用的影响整体大于中性盐Na2SO4。     

不同栽植密度对库尔勒香梨光合荧光特性的影响

以树龄20年生库尔勒香梨为试材,采用Li-6400光合仪,测定分析了3m×5m、4m×5m、5m×6m3个不同栽植密度下库尔勒香梨净光合速率(Pn)、蒸腾速率(Tr)、胞间CO2浓度(Ci)、气孔导度(Gs)的变化,利用调制式OS-30P荧光仪测定了初始荧光(Fo)、最大荧光(Fm)、最大PSⅡ光能转换效率(Fv/Fm)和PSⅡ潜在活性(Fv/Fo),研究了不同栽植密度对库尔勒香梨光合荧光特性的影响,旨在选出当地最适宜的栽植密度。结果表明:不同栽植密度对库尔勒香梨光合特性影响很大,3个处理间除Gs和Fo差异不显著外,Pn、Tr、Ci、Fm、Fv/Fm、Fv/Fo值的差异都达到了极显著水平;Pn的日均值以4m×5m最大,5m×6m次之,3m×5m最小,Fv/Fm的日均值表现为4m×5m高于5m×6m,而低于3m×5m。试验表明,20年生库尔勒香梨3个栽植密度以4m×5m光合效率最强,5m×6m其次,3m×5m最弱。     

不同pH的ALA处理对葡萄叶片光合及叶绿素荧光特性的影响

以日光温室栽培的"克瑞森"无核葡萄为试材,在其果实膨大期(6月18日)、转色期前(7月2日)、转色期(7月12日)对叶片进行清水和不同pH(5.5、6.0、6.5、7.0)的ALA喷施处理,研究不同pH的ALA处理对葡萄叶片光合及叶绿素荧光特性的影响。结果表明:不同pH的ALA处理均会不同程度地提高光合参数包括净光合速率(Pn)、气孔导度(Gs)、胞间CO2浓度(Ci)、蒸腾速率(Tr)和荧光参数包括最大荧光(Fm)、潜在光化学活性(Fv/Fo)、最大光化学效率(Fv/Fm)、实际光化学效率(Y(Ⅱ))、光化学猝灭系数(qP),非光化学猝灭系数(NPQ),降低最小荧光(Fo),其中以pH 5.5的ALA处理作用效果最为显著。     

5-氨基乙酰丙酸对亚适宜温光条件下黄瓜幼苗光合特性的影响

为了弄清外源5-氨基乙酰丙酸(ALA)提高亚适宜温光下黄瓜幼苗光合作用的效果,以‘津优1号’黄瓜为试材,用0.5mg·mL-1ALA喷洒幼苗,利用光照培养箱模拟亚适宜温光条件(昼/夜温度18℃/12℃,光量子通量密度300μmol.m-2.s-1),研究ALA对幼苗气体交换参数、叶绿素荧光参数及光合酶活性的影响。结果表明:亚适宜温光下,黄瓜幼苗叶片的净光合速率(Pn)和气孔导度(Gs)、羧化效率(CE)、表观量子效率(AQY)、光下实际光化学效率(ΦPSⅡ)、光化学猝灭系数(qP)、天线转化效率(Fv′/Fm′)及核酮糖-1,5-二磷酸羧化酶(RuBPCase)、果糖-1,6-二磷酸酶(FDPase)活性等均明显降低,胞间CO2浓度(Ci)升高,光补偿点(LCP)、CO2补偿点(CCP)显著下降。与水处理相比,ALA处理的Pn、Gs、CE、AQY、ΦPSⅡ、qP、Fv′/Fm′及RuBPCase和FDPase活性等有不同程度提高,Ci、LCP和CCP有所降低。亚适宜温光下,黄瓜幼苗光合速率下降的主要原因是非气孔限制,外源ALA能明显提高其光合作用。     

外源水杨酸对NaCl胁迫下番茄幼苗光合特性的影响

采用营养液栽培,研究了外源水杨酸对NaCl胁迫下番茄叶片光合作用和叶绿素荧光参数的影响。结果表明：在NaCl胁迫条件下进行SA处理,番茄叶片净光合速率（Pn）、气孔导度（Gs）均较NaCl胁迫条件下未加SA处理有明显的增加。SA处理减缓了细胞间隙CO₂浓度（Ci）、气孔限制值（Ls）的升、降速度。外源SA减小了NaCl胁迫下番茄叶片叶绿素含量、PSⅡ原初光能转换效率（Fv/Fm）、PSⅡ的潜在活性（Fv/Fo）、光合电子传递量子效率（ΦPSⅡ）、叶绿素光化学猝灭系数（qP）的下降以及初始荧光（Fo）、非光化学猝灭系数（NPQ）的升高。说明外源SA对NaCl胁迫下番茄叶片光合系统的破坏具有保护作用。     

高温胁迫对丹参光合生理指标及叶绿素荧光特性的影响

以丹参为试材,采用土培盆栽法,于第1茬花开前进行高温胁迫处理,研究了高温胁迫对丹参生理指标、光合及叶绿素荧光特性的影响。结果表明:随着高温胁迫时间的延长,丹参叶片超氧化物歧化酶(SOD)活性呈上升趋势,而过氧化氢酶(CAT)活性呈下降趋势;丙二醛(MDA)、游离脯氨酸(Pro)含量均呈上升趋势,且与胁迫时间呈极显著多项式关系。净光合速率(Pn)、气孔导度(Gs)、胞间二氧化碳浓度(Ci)和蒸腾速率(Tr)均呈下降趋势,且各指标均与胁迫时间呈负相关。最大光化学量子产量(Fv/Fm)、PSⅡ潜在光化学活性(Fv/Fo)、有效光化学量子产量(Fv′/Fm′)、光化学淬灭系数(qP)和表观光合电子传递速率(ETR)均呈下降趋势,且各指标均与胁迫时间呈负相关,非光化学淬灭系数(NPQ)呈先上升后下降趋势。研究表明,高温(40℃)对丹参生理指标、光合及叶绿素荧光特性有较大的影响,且各功能指标共同作用,以减轻植株所受伤害。     

硝普钠对低氧胁迫下黄瓜幼苗生长、光合及叶绿素荧光参数的影响

以"中农8号"黄瓜为试材,采用营养液水培的方法,通过添加不同浓度(0.1、0.3、0.5mmol·L^-1)的硝普钠(SNP)作为一氧化氮(NO)供体,研究了外源NO对低氧胁迫下黄瓜生长、光合及叶绿素荧光参数的影响。结果表明:在低氧胁迫下黄瓜植株的生长、光合作用以及光合系统活性均受抑制,添加不同浓度的SNP,显著促进了低氧胁迫下黄瓜幼苗生长和光合作用,光合系统活性也得到显著提高,低氧胁迫伤害得到有效缓解,主要表现为株高、茎粗、主根长、根体积、根系活力、地上鲜质量和地下干鲜质量显著提高;幼苗叶片的Pn、Gs和WUE显著提高,Ci显著降低;Fv/Fm、ETR、qP、ΦPSⅡ显著提高,NPQ显著降低。其中最适SNP添加浓度为0.1mmol·L^-1。     

Identification of S-haplotypes of European cultivars of sour cherry

The sour cherry is known to exhibit the phenomenon of gametophytic self-incompatibility which prevents self-fertilization. In sour cherry, besides self-incompatible cultivars, there often occur self-compatible cultivars. This is due to the occurrence of natural mutations of the S-RNase or SFB genes and, consequently, loss of functionality of S-alleles. Here we present the results of the identification of S-haplotypes of 21 cultivars of sour cherry from various regions of Europe. The analyses were performed using methods based on the amplification of intron I and intron II of the S-RNase gene and fragments specific to the individual alleles of the S-RNase or SFB genes. The tested cultivars were found to contain 15 S-haplotypes: S₁, S_1?, S₄, S₆, S_6m, S_6m2, S₉, S₁₂, S₁₃, S_13?, S₂₆, S₃₅, S_36a, S_36b, and S_36b2. The most frequently occurring S-haplotypes were S_13? (61.9%), S_36a (57.1%), and S₂₆ (47.6%). On the basis of the results, 17 of the 21 cultivars were deduced to be self-compatible. The results will be of use in the production of sour cherry fruit by facilitating the selection of suitable pollinating cultivars. The results are also expected to be useful in the breeding of new cultivars of sour cherry when selecting genotypes for crosses.     

京白梨等品种S 基因型鉴定及新基因S28 和S30 的核苷酸序列分析

 根据梨S基因高度保守区C1和C3区, 设计1对引物P1和P2, 对梨品种的基因组DNA进行S基因特异扩增、克隆、测序, 并在GenBank中BLAST比较, 确定S 基因特异性片段, 对京白梨等6个供试自交不亲和品种的S基因型比对结果为: 白梨中的‘库尔勒香梨’为S₂₁ S₂₈ , ‘苹果梨’为S₁₇S₁₉ ; 砂梨中的‘台湾蜜梨’为S₁₁ S₂₂ ; 西洋梨中的‘葫芦梨’为S_a S_b; 秋子梨中的‘京白’为S₁₆ S₃₀ , ‘早梨18’为S₄ S₂₈。其中S₂₈和S₃₀为首次登录的新S 基因, 在GenBank的登录号分别为AY562394 (库尔勒香梨) 和AY876945 (京白) 。     

The effect of organic supplementation of solarized soil on the quality of tomato fruit

Soil solarization, used to control weeds and soil-borne pathogens in hot climates, has not yet been widely adapted as a commercial practice because of its lack of efficacy. Experiments were carried out in southern Italy over two growing seasons to study the effect of three levels (0, 0.35 and 0.7 kg m⁻²) of organic supplementation of the soil prior to solarization on soil mineral availability and fruit quality attributes. Soil temperature and chemical properties were monitored, together with changes in the physical characteristics and chemical composition of tomato fruits grown under commercial greenhouse conditions. Organic supplementation increased the soil temperature achieved through solarization by 3.9 to 5.5 °C. Organic supplementation increased (P ≤ 0.05) the soil concentration of NO₃⁻-N, exchangeable K₂O, Ca²⁺, Na⁺ and Mg²⁺ and the level of electrical conductivity in the soil extract. Physical characteristics of tomato fruits were improved by supplementation, with fresh and dry weight enhanced up to 11 and 21%, respectively, mesocarp thickness up to 19%, firmness up to 36% and skin redness (a^*/b^* ratio) up to 24%. As the supplementation rate was raised from 0 to 0.7 kg m⁻², the fruit content of reducing sugars increased (P ≤ 0.01) from 1.75 to 2.14 g per 100 g f.w., ash from 0.49 to 0.62%, soluble solid from 5.12 to 6.18 °Brix, titratable acidity from 0.16 to 0.19%, and ascorbic acid from 25.1 to 32.5 mg 100 mL⁻¹. We concluded that organic supplementation appears to be a valuable and environmentally friendly way to improve the mineral availability in the soil and improve fruit quality of tomato.     

金嘴蝎尾蕉切花苞片褐变的控制

 研究了金嘴蝎尾蕉切花最佳采收时期和对其苞片褐变具有良好控制效果的预处理保鲜液及瓶插方法。结果表明: 金嘴蝎尾蕉以中蕾期采收最佳; 整个花枝水平放置, 完全浸泡于500 mg·L ^{- 1} H₃BO₄或500 mg·L ^{- 1} MgSO₄中1 h后, 结合2 mg·L ^{- 1} 6-BA + 200 mg·L ^{- 1} Al₂ ( SO₄ ) 3瓶插保鲜及0.1%聚乙烯醇喷洒花枝, 可显著控制苞片褐变, 保持组织较低水平pH值, 减缓膜透性的上升。其瓶插寿命分别达12 d和11.5 d, 显著高于对照的4 d。     

化学药剂对香椿休眠解除的影响及其机理

 采用五元二次正交旋转组合设计, 探索6-BA、GA₃ 、(NH₂) ₂CS、ZnSO₄ 、KNO₃ 对香椿休眠解除的影响, 5 种化学药剂解除休眠的作用依次为ZnSO4 > (NH₂) ₂CS > GA₃ > 6-BA > KNO₃ 。打破香椿休眠的最佳药剂组合是: 6-BA 20 mg/L + GA₃ 180 mg/L + (NH₂) ₂CS 1 % + ZnSO4 0.5 % + KNO₃ 2 %。用上述药剂处理可以使香椿提早23 d 萌芽。     

Comparison of anthocyanins in non-blotches and blotches of the petals of Xibei tree peony

A comparison in non-blotches and blotches of 35 cultivars of Xibei tree peony was investigated to explore flower coloration of Xibei tree peony (the second cultivar group in Chinese tree peony). With high performance liquid chromatography (HPLC) analysis, six anthocyanins including peonidin 3,5-di-O-glucoside (Pn3G5G), peonidin 3-O-glucoside (Pn3G), cyanidin 3,5-di-O-glucoside (Cy3G5G), cyanidin 3-O-glucoside (Cy3G), pelargonidin 3,5-di-O-glucoside (Pg3G5G), and pelargonidin 3-O-glucoside (Pg3G) were detected in non-blotches and blotches of petals. Total anthocyanins (TA), total flavones and flavonols (TF), and the copigmentation index (CI) were also analyzed. Cyanidin-based glycosides, which accumulated abundantly at the basal petal, resulted in blotch formation. Some peculiar cultivars with only one kind of anthocyanins or without anthocyanins in non-blotches were found in this study. For example, ‘Feng Zi Xiu Se’, ‘Ou Duan Si Lian’, and ‘Xi Wang’ contained only Pn3G5G; ‘Bing Shan Cang Yu’ and ‘Jin Bo Dang Yang’ contained only Cy3G; while no anthocyanins were found in ‘Bing Shan Xue Lian’. Several cultivars were rich in Pg-based glycosides, such as ‘Ni Hong Huan Cai’, and ‘Ju Yuan Shao Nv’. These cultivars would be excellent parents for creating new cultivars with novel flower color in the future.     

麝香百合胚性愈伤组织状态的调整与植株再生

采用麝香百合假鳞茎诱导出的胚性愈伤组织,从氯化钴、ABA、蔗糖浓度以及光照条件等4个方面对胚性愈伤组织的状态进行调整,并利用活性炭进行了再生实验。结果表明：0.05 μmol·L^-1的氯化钴有利于提高体细胞胚的比例和愈伤组织的颗粒性,0.02 μmol·L^-1和0.01 μmol·L-1的氯化钴有利于愈伤体积增大和增殖系数提高;ABA随着其浓度提高,对胚性愈伤的长势、干湿程度、增殖体积和增殖系数的抑制效果逐渐明显,但对胚性愈伤比例和颗粒性的抑制效果不显著;光培养条件下,90 g·L^-1和60 g·L^-1蔗糖对麝香百合胚性愈伤的比例和颗粒性都有较好的影响,但在暗培养条件下,仅仅60 g·L^-1蔗糖的效果较好;光培养和暗培养对胚性愈伤的干湿程度和颗粒性都没有显著的影响;1 g·L-1的活性炭和基本培养基对愈伤的再生具有显著性的影响。综合结果,麝香百合胚性愈伤的最佳增殖方式和再生方式分别为：为采用光培养,培养基为MS + NAA 5.4 μmol·L^-1 + TDZ 0.4 μmol·L^-1 + CoC1₂ 0.05 μmol·L^-1 + 蔗糖60 g·L^-1和MS+活性炭(1g/L) +蔗糖30 g·L^-1 。     

5种国兰( Cymbidium ) 的光合特性

 通过气体交换和叶绿素荧光分析等方法研究了5种国兰(Cymbidium ) 的光合特性。其光饱和点、光补偿点、CO₂ 补偿点和CO₂ 饱和点表明它们具有C3 植物特征; 光合速率在3.0 ～5.9 μmol·m^{- 2} ·s^{- 1}之间, 在低于2 000 μmol·mol^{- 1} CO₂ 浓度下, 光合速率受CO₂ 浓度影响较大; 5种国兰的光合能力、表观量子效率、羧化效率等都有所差异; 光饱和点在350～650μmol·m^{- 2} ·s^{- 1}之间, 属于喜阴植物,其中春兰、建兰耐阴性相对较低, 墨兰、春剑耐阴性相对较高, 蕙兰居中。从暗处暴露到强光下, 5种国兰的光化学反应启动差异较大, 启动后的光化学效率差异也较大, 这可能与国兰不同种起源地的生态环境,适应性及进化有关。     

Physiological response of onion plants to foliar application of putrescine and glutamine

Two field experiments were carried out in Egypt during two successive seasons (2007/2008 and 2008/2009). This study aimed to investigate the response of growth, yield quality and some metabolic constituents of onion (Allium cepa L. cv. ‘Giza 20’) to foliar application of putrescine (Put; 25, 50 and 100 mg L⁻¹) and glutamine (Glut; 50, 100 and 200 mg L⁻¹), the former a diamine and the latter an amino acid, either alone, or in combination. Foliar application of Put and Glut, either alone or in combination, significantly increased plant height, number of leaves, fresh weight of leaves/plant, fresh and dry weight/plant, leaf area, leaf area/plant, bulb length, bulb diameter and weight, as well as yield of onion and quality of bulbs. Total soluble sugars, sulfur compounds, total soluble phenols, total free amino acids and total photosynthetic pigment content in leaves were increased by increasing Put and/or Glut concentrations up to 100 and 200 mg L⁻¹, respectively. Generally, foliar application of Put at 100 mg L⁻¹ and Glut at 200 mg L⁻¹ singly, or combined, effectively increased bulb yield and quality. In conclusion, the yield-contributing characters and quality of onion could be improved by application of Put and/or Glut.     

Improvement of flower color by means of leaf treatments in lily

Flower color, an important feature biologically and commercially, is based on four natural pigments – flavonoids, carotenoids, betalains and chlorophylls. Temperature, light, nutrition – as well as additions of sugar, salt, or metals to the conservation water – have an effect on pigmentation. We investigated the effects of K-sulphate and/or sucrose on flower color in leaf treatments applied 30–10 days before harvest to four Asiatic lily (Lilium × elegans Thunb.) cultivars during the winter and summer. Colors of tepals were evaluated by a portable spectrocolorimeter that calculates the standard CIE L*a*b* coordinates and the color differences (E). After leaf treatments during both seasons, cultivars with flowers with high red components (e.g. the purple ‘Fangio’ and the pink ‘Brindisi’) showed significant improvements in color quality. The orange-flowered ‘Tresor’ showed improvement only if K-sulphate and Mix (K-sulphate and sucrose) solution treatments were applied during the summer. The yellow-flowered ‘Menorca’ was not affected by treatments during either summer or winter forcing season. Especially in the winter, a significant reduction in flower abortion was observed for cut flowers of all cultivars. In summer only ‘Fangio’ and ‘Tresor’ showed a reduction in flower abortion. Also, flower size and longevity were improved by the leaf treatment. The results, obtained from a commercial nursery operation, demonstrate that lily growers can adopt a very simple and inexpensive treatment to improve important qualitative traits of their product.