大豆C4途径与光系统Ⅱ光化学功能的相互关系

测定了不同发育时期大豆（Ｇｌｙｃｉｎｅ ｍａｘ（Ｌ）Ｍｅｒｒ．）“黑农４１”叶片的４种Ｃ４酶（ＰＥＰＣａｓｅ（磷酸烯醇式丙酮酸羧化酶）、ＮＡＤＰ－ＭＤＨ（ＮＡＤＰ苹果酸脱氢酶）、ＮＡＤＰ－ＭＥ（ＮＡＤＰ苹果酸酶）和ＰＰＤＫ（丙酮酸磷酸二激酶））活性、荧光动力学数值（Ｆｖ／Ｆｏ（ＰＳⅡ活性）、ｑＰ（光化学淬灭）、ｑＮ（非光化学淬灭、ΦＰＳⅡ（有效ＰＳⅡ光化学效率））和光合速率。结果表明在“黑农４１”     

不同光合特性大豆叶的比较解剖研究

本研究选取不同光合速率的品种‘黑农26’（高产低光效）、‘黑农40’、‘黑农41’（高产高光效）为材料,于大豆开花后的不同生育时期,对大豆的功能叶片、叶柄解剖学进行了研究。结果表明：（1）不同类型大豆的叶肉结构有明显区别。叶片厚度依次为‘黑农40’>‘黑农41’>‘黑农26’。各期的基本趋势是一致的。栅栏组织的厚度和层数与叶片的厚度趋势一致。（2）各品种栅栏组织中的叶绿体数目均多于海绵组织,且高光效类型多于低光效类型。局部观察不 同品种间,叶绿体内的基粒和间质片层结构高光效的也明显优于低光效的品种。（3）气孔包含数量和大小两个因素,气孔大小基本一致,下表皮数量>上表皮,高光效类型>低光效类型。（4）各品种主脉维管束中木质部的导管数目依次为‘黑农41’>‘黑农40’>‘黑农26’。     

脂氧合酶对黄瓜叶片光合电子传递活性的影响

黄瓜（Ｃｕｃｕｍ ｉｓｓａｔｉｖｕｓＬ．）叶片的光合作用与电子传递活性随叶片衰老而降低,脂氧合酶（Ｌｏｘ）活性则相应增高。大豆Ｌｏｘ－１ 抑制黄瓜子叶分离的叶绿体ＰＳⅡ电子传递活性,没食子酸丙酯（ＰＧ）或槲皮酮（ＰＦ）能消除这种抑制作用。二氯苯二甲脲（ＤＣＭＵ）或２,３－二溴百里香醌（ＤＢＭＩＢ）存在时,大豆Ｌｏｘ－１ 对ＰＳⅡ电子传递活性有抑制作用,加入ＰＧ 使活性恢复到接近原有水平。二苯卡巴肼（ＤＰＣ）对经Ｌｏｘ－１ 处理的叶绿体ＰＳⅡ电子传递活性有明显恢复作用。Ｌｏｘ－１ 使Ｃｈｌａ室温荧光Ｆｍ 降低,ＤＰＣ则能轻微恢复Ｆｍ 。可见,ＰＳⅡ氧化侧、Ｑ与ＰＱ 位点都对Ｌｏｘ－１ 的作用敏感。Ｌｏｘ－１ 对叶绿体色素的漂白作用,以及活性氧对ＰＳⅡ电子传递活性的抑制,可能是Ｌｏｘ 影响光合膜功能的重要原因之一     

强光及活性氧对大豆光合作用的影响

利用叶绿素荧光技术研究了强光及活性氧对大豆（ Ｇｌｙｃｉｎｅ ｍａｘ Ｌ．） 光合作用的影响。结果表明,大豆叶片在强光（２０００ μｍｏｌ·ｍ － ２·ｓ－ １） 下照射２ ｈ 后,净光合放氧速率下降。随着处理光强的增加,叶绿素荧光参数Ｆｍ／Ｆｏ、Ｆｖ／ Ｆｍ 、ΦＰＳⅡ、ｑＰ 和ｑＮ 均呈下降趋势。在强光处理大豆叶片时,加入外源活性氧Ｈ２Ｏ２ 、Ｏ－·２ 、·ＯＨ 和１Ｏ２ 后,大豆叶片受到伤害。其中１Ｏ２ 和·ＯＨ 的破坏作用十分明显,表现为Ｆｖ／ Ｆｍ 和ΦＰＳⅡ的明显降低。抗氧化剂ＤＡＢＣＯ、甘露醇、抗坏血酸和组氨酸对强光下的大豆叶片有保护作用,但这种保护作用不强。在暗处理叶片时,超氧物歧化酶（ＳＯＤ）的抑制剂ＤＤＣ对Ｆｍ／ Ｆｏ 和Ｆｖ／Ｆｍ 的影响不大;抗坏血酸过氧化物酶（ＡＰＸ） 的抑制剂ＮａＮ３ 使Ｆｖ／Ｆｏ、Ｆｖ／ Ｆｍ和ΦＰＳⅡ下降明显。强光处理大豆叶片时,ＤＤＣ明显降低Ｆｍ／ Ｆｏ、Ｆｖ／ Ｆｍ 和ΦＰＳⅡ,ＮａＮ３ 降低Ｆｍ／ Ｆｏ、Ｆｖ／ Ｆｍ 和ΦＰＳⅡ的作用则更大。据此推测,在强光下大豆发生了光抑制,光抑制的发生与活性氧的存在有一定的关系     

叶绿素缺乏的大麦突变体的光合作用和叶绿素荧光

和早熟３号大麦（野生型）（ＤＧ）相比,黄化大麦（突变体）（ＬＧ）叶片Ｃｈｌ含量低,而Ｃｈｌａ／ｂ较高;光合速率低,表现量子效率低,而饱和光强较高,气孔导度较高;荧光参数Ｆｏ低,而ＰＳⅡ的光化学效率（Ｆｖ／Ｆｍ）以及Ｔ１／２、Ｆｍ／Ｆｏ、Φｅ均高。以单位叶绿素计算,黄化大麦的ＰＳⅡ电子传递活性和全链电子传递活性较高,而ＰＳⅠ电子传递活性较低。推测黄化大麦ＰＳⅡ的光化学效率增高可能是由于其ＰＳⅡ向ＰＳⅠ传递的激发能较少,是对Ｃｈｌ含量低的一种补偿。     

大豆叶片C4循环途径酶

以不同产量水平的大豆（Glycine max(L.)Merr.)品种“黑农40”和“黑农37”为实验材料,研究了苗期,开花期,初荚期和鼓粒期等不同发育时期的叶片中磷酸烯醇式丙酮酸羧化酶（PEPCase),NADP－苹果酸氢酶（NADPMDH）,NADP－苹果酸酶（NADP－ME）,丙酮酸磷酸双激酶（PPDK）等C4途径的主要酶和1,5－二磷酸核酮糖羧化酶（RuBPCase）的活性变化,结果表明两种大豆叶片均含有上述4种酶,而且从PEPCase/RuBPCase的比值看,C4酶在高产大豆“黑农40”叶片中表达较高,表明C4循环途径与大豆产量密切相关,这一结果还暗示有可能通过检测C4途径酶的表达水平及比例,筛选出具有高产潜力的大豆种质。     

叶绿素缺乏的大麦突变体的光合作用和叶绿素荧光

和早熟３号大麦（野生型）（ＤＧ）相比,黄化大麦（突变体）（ＬＧ）叶片Ｃｈｌ含量低,而Ｃｈｌ ａ／ｂ较高;光合速率低,表观量子效率低,而饱和光强较高,气孔导度较高;荧光参数Ｆｏ低,而ＰＳⅡ的光化学效率（Ｆｖ／Ｆｍ）以及Ｔ１／２、Ｆｍ／Ｆｏ、Φｅ均高。以单位叶绿素计算,黄化大麦的ＰＳⅡ电子传递活性和全链电子传递活性较高,而ＰＳＩ电子传递活性较低。推测黄化大麦ＰＳⅡ的光化学效率增高可能是由于其ＰＳⅡ向Ｐ     

盐胁迫下CO_2浓度倍增对冬小麦叶绿体光能吸收和激发能分配的影响

研究了在盐胁迫下ＣＯ２浓度倍增对冬小麦（Ｔｒｉｔｉｃｕｍａｅｓｔｉｖｕｍ）京冬８号叶片光合色素含量,叶绿体对光吸收能力,激发能在两个光系统之间分配和一些荧光诱导动力学参数的影响。结果表明,ＣＯ２倍增能提高冬小麦叶片单位鲜重叶绿素（Ｃｈｌ）和类胡萝卜素（Ｃａｒ）的含量,以及含等量Ｃｈｌ的叶绿体对光能的吸收能力,增强Ｍｇ２＋对两个光系统（ＰＳⅠ和ＰＳⅡ）之间激发能分配的调节能力;ＣＯ２倍增还提高荧光猝灭速率（ΔＦｖ／Ｔ）,而降低荧光半上升时间（Ｔ１／２）。然而,盐胁迫的作用则与高ＣＯ２浓度恰恰相反。     

不同光合特性大豆叶的比例解剖研究

本研究选取不同光合速率的品种‘黑农26'(高产低光效)、‘黑农40'、‘黑农41'(高产高光效)为材料,于大豆开花后的不同生育时期,对大豆的功能叶片、叶柄解剖学进行了研究.结果表明(1)不同类型大豆的叶肉结构有明显区别.叶片厚度依次为‘黑农40'>‘黑农41'>‘黑农26'.各期的基本趋势是一致的.栅栏组织的厚度和层数与叶片的厚度趋势一致.(2)各品种栅栏组织中的叶绿体数目均多于海绵组织,且高光效类型多于低光效类型.局部观察不同品种间,叶绿体内的基粒和间质片层结构高光效的也明显优于低光效的品种.(3)气孔包含数量和大小两个因素,气孔大小基本一致,下表皮数量>上表皮,高光效类型>低光效类型.(4)各品种主脉维管束中木质部的导管数目依次为‘黑农41'>‘黑农40'>‘黑农26'.     

青海高原及上海平原地区植物叶片光合作用的光抑制

用便携式ＡＤＣ光合气体分析系统和便携式ＣＦ－１０００荧光仪对青海和上海的同一植物和不同植物叶片光合作用的光抑制进行了测定。结果表明,两地在晴天强光下,中午植物叶片光系统Ⅱ（ＰＳⅡ）的光化学效率（Ｆｖ／Ｆｍ）和表观光合量子效率（ＡＱＹ）的日变化比早晨低;上海测定ＰＳⅡ的Ｆｖ／Ｆｍ和ＡＱＹ的日变化比青海的下降幅度大。ＡＱＹ的日变化曲线比ＰＳⅡ的Ｆｖ／Ｆｍ低,ＡＱＹ降低的幅度比ＰＳⅡ的Ｆｖ／Ｆｍ大。两地植物均有不同程度的光合作用光抑制,且上海比青海的大     

运用叶绿素a荧光诱导动力学技术检测水稻生产潜力

运用叶绿素a荧光诱导动力学技术,检测水稻叶片和叶绿体的PSII原初光转化效率(F_v/F_m)或与此相关可代表PSII潜在活性(F_v/F_o)的参数,结果表明,不同产量水平的水稻品种之间,其叶片和叶绿体的F_v/F_m(或F_v/F_o)的比值,以及光合电子传递速率均有明显差异.此外,在外源Mg~(2+)的存在下,高产水稻品种叶绿体有更高的原初光能转化效率,同时Mg~(2+)对高产品种叶绿体PSII和PSI之间激发能分配的调节能力也较低产品种者高.实验说明Chl a荧光诱导动力学的技术,能够作为一种快速、灵敏和简便的有效方法用于早期检测水稻(或其他作物)的生产潜力.     

C4 Pathway Enzymes in Soybean Leaves

High-yielding soybean ( Glycine max (L.) Merr.) variety, “Heinong 40”, and one control variety, “Heinong 37”, were used as experimental materials. The activities of C4 pathway enzymes, i.e. PEPCase (phosphoenolpyruvate carboxylase), NADP-ME (NADP-malic enzyme), NADP-MDH (NADP-malate dehydrogenase), PPDK (pyruvate phosphate dikinase) and RuBPCase (ribulose-1.5-bisphosphate carbozylase) were assayed at seedling, blooming, pod-bearing and pod-filling stage. The results indicated that C4 pathway enzymes were expressed differently at different developing stages in both varieties of soybean, but the ratio of PEPCase and RuBPCase showed that the expression of C4 pathway enzymes of “Heinong 40” was higher than those of “Heinong 37” at each stage. The results showed that C4 pathway enzymes were closely related to the crop yielding potential. Therefore, it is possible to select potentially high-yielding soybean variety by the expression of C4 pathway enzymes.     

超级高产小麦旗叶荧光动力学研究

探明超级小麦品种的旗叶光合作用与荧光动力学特性,为超级小麦品种选育利用提供理论依据。以超级小麦临麦4号为试验材料,应用CI-301PS型便携式光合作用测定系统和FMS-2便携式荧光测定仪(英国Hansatech公司)在田间试验中测定旗叶光合作用与荧光动力学参数。结果表明,与普通高产对照品种皖麦52和烟农19相比,超级小麦临麦4号的光合作用参数光合速率、光饱和点和CO2饱和点、羧化效率高,光补偿点和CO2补偿点低;光合机构系统工作参数PSII实际的光化学效率(ΦPSII)、光化学猝灭系数(qP)、PSII反应中心的激发能捕获效率(Fv/Fm)、PSⅡ潜在活性Fv/Fo和电子传递速率(ETR)值高,非光化学猝灭系数(NPQ)值低。这表明超级小麦临麦4号的光合机构系统工作能力强和工作效率高,保证旗叶光合作用的高效运行,为子粒灌浆提供充足的能量和碳水化合物。     

17个建兰品种光合特性分析

以17个建兰(Cymbidium ensifolium)品种为材料,采用改良的丙酮法提取叶绿素,再通过Arnon丙酮法公式计算光合色素含量,利用捷克FluorCam开放式叶绿素荧光仪测定不同品种的叶绿素荧光参数。结果表明,17个建兰品种的光合色素和叶绿素荧光参数具有不同程度的差异,其中‘铁骨素’(C. ensifolium ‘Tiegusu’)、‘逸红双娇’(C. ensifolium ‘Yihongshuangjiao’)和‘闽南黄蝶’(C. ensifolium ‘Minnanhuangdie’)的光合色素含量高于其他品种,表明这3个品种具有良好的光合效率,吸收光能的能力较强;‘铁骨素’最大荧光产量(Fm)、Kautsky诱导效应最大荧光(Fp)、PS Ⅱ原初光能转化效率(Fv/Fm)和非光化荧光淬灭系数(NPQ)均为最高。综上可知,‘铁骨素’的光合生理特性优于其他品种,可作为优良建兰品种进行种植推广。     

Effects of Strong Light and Active Oxygen on Photosynthesis in Soybean

With the use of chlorophyll fluorescence technique, it was found that the net photosynthetic oxygen evolution rate decreased after strong light (2 000 μmol· m-2·2-1 ) treatment for two hours in soybean ( Glycine max L. ) leaves. The chlorophyll fluorescence parameters, Fm/Fo, Fv/Fm, ФPSII, qp and qN decreased along with the increase of light intensity. In strong light, exogenous active oxygen H202、·OH and 'O2 were harmful to soybean leaves. The destruction of 'O2 and·OH to leaves was most evident, as was shown that Fv/Fm and PS H decreased significantly. The antioxidants DABCO, mannitol, ascorbate and histidine protected the leaves, but weakly, from strong light. In darkness, the SOD inhibitor sodium diethyldithiocar- bamate (DDC) had no significant effect on Fm/Fo and Fv/Fm, but NAN,, the ascorbate peroxidase (APX)inhibitor, significantly decreased Fm/Fo, Fv/Fm and ФPS II. In strong light, however, beth DDC and NaN3 reduced the above-mentioned fluorescence parameters, but NaN3 was more effective than DDC. The results suggested that photoinhibition did take place in soybean leaves under strong light, and it was related to active oxygen in vivo.     

大豆C4途径与光系统Ⅱ光化学功能的相互关系

Four C4 pathway enzymes of “Heinong 41" leaves of soybeans (Glycine max　（L） Merr.) were assayed in five developmental stages. Pn (the net photosynthetic rate) and the chlorophyll fluorescence parameters (Fv/Fo, qP, qN and ΦPSⅡ) were also measured. The results indicated that the activities of C4 enzymes, Pn, the chlorophyll fluorescence parameters and the ratio of PEPCase (PEP carboxylase)/RuBPCase (ribulose-1,5-biphosphate) shared the same changing trait during the whole developmental stages of “Heinong 41". Correlation analysis showed that the activities of C4 enzymes, Pn, the chlorophyll fluorescence parameters were positively correlated with the ratio of PEPCase/RuBPCase. All these suggested that the degree of C4 pathway expression in “Heinong 41" leaves were positively correlated with its Pn; the photochemical function of PSⅡ was adjusted to meet the specific energy requirements for the operation of C4 pathway with the improvement of C4 expression.     

超高产杂交水稻皮秒分辨荧光特性

采用时间分辨荧光光谱测试系统,研究了超高产杂交水稻(Oryza sativa L.)两优培九(P9)和对照汕优63(SH 63)类囊体膜的荧光光谱特性和时间特性.以脉宽为120 ps,重复率为4MHz,波长为514 nm的Ar+激光分别激发P9和SH 63水稻类囊体膜荧光.通过对其超快荧光的时间特性和光谱特性比较研究发现:无论是在灌浆期还是在扬花期,P9水稻类囊体膜中光系统I激发能传递的速度比光系统Ⅱ的快;P9和SH 63两种水稻类囊体膜在灌浆期的激发能传递速度都比扬花期的快;两种水稻类囊体膜的光谱特性还给出,在从扬花期到灌浆期这一生长发育过程中,SH 63水稻类囊体膜的色素成分和结合状态发生了变化,而P9却没有出现这种变化.     

Effects of Drought Stress on Key Enzymes of Carbon Metabolism,Photosynthetic Characteristics and Agronomic Traits of Soybean at the Flowering Stage under Different Soil Substrates

Soybean is an important legume food crop, and its seeds are rich in nutrients, providing humans and animals with edible oil and protein feed. However, soybean is sensitive to water requirements, and drought is an important factor limiting soybean yield and quality. This study used Heinong 84 (drought resistant variety) and Hefeng 46 (intermediate variety) as tested varieties planted in chernozem, albic, and black soils. The effects of drought stress on the activities of key enzymes in carbon metabolism and photosynthetic characteristics of soybean were studied during the flowering stage, most sensitive to water. (1) The activities of SS-1, 6PGDH, and G6PDH enzymes in soybean leaves first increased and then decreased under drought stress. The enzyme activity was the highest under moderate drought stress and weakest in the blank group. (2) Drought stress increased Phi2, PhiNO, and Fm in soybean leaves and reached the highest value under severe drought; with the increase in drought stress, PhiNPQ and Fv/Fm of soybean leaves gradually decreased, reaching the lowest under severe drought. (3) With the increase in drought stress, F₀ and Fs of soybean leaves showed a single peak curve, and the maximum was at moderate drought. (4) Correlation analysis showed that F₀ was greatly affected by varieties and soil types; Fs, F0, and Fm soil varieties had a great influence, and chlorophyll fluorescence parameters were affected differently under drought stress with different drought degrees. (5) Drought stress changed the agronomic traits and yield of soybean. With the increase of drought degree, plant height, node number of main stem, effective pod number, 100-seed weight and total yield decreased continuously. (6) Drought stress affected the dry matter accumulation of soybean. With the increase of drought degree, the dry matter accumulation gradually decreased. Among them, the leaf was most seriously affected by drought, and SD decreased by about 55% compared with CK. Under the condition of black soil, the dry matter accumulation of soybean was least affected by drought.     

不同品种美国山核桃叶绿素荧光参数日变化的研究

以湖南省永州市冷水滩采穗圃中的美国山核桃为试材,研究了叶绿素荧光参数的日变化规律。结果表明:初始荧光(Fo)、最大荧光(Fm)、PSII原初光能转化效率(Fv/Fm)、光合量子产额(Yield)、光化学猝灭系数(qP)、非光化学猝灭系数(qN)和表观电子传递速率(ETR)均存在着明显的日变化。其中Fv/Fm、Fm、Yield、qP均呈先下降后上升的趋势,在中午强光下降低到最低值;qN则呈先上升后下降的趋势,在中午时分达到峰值;Fo呈下降趋势,部分品种傍晚稍有回升,但仍比早晨低;ETR日变化呈双峰曲线。不同品种间Fv/Fm、Yield、ETR、qP、qN对光强和温度的响应也存在着明显差异,可作为鉴定品种耐光抑制能力大小的指标。