Characterization of high-yield performance as affected by genotype and environment in rice

We characterized yield-relevant characters and their variations over genotypes and environments （locations and years） by examining two rice varieties （9746 and Jinfeng） with high yield potential. 9746 and Jinfeng were planted in two locations of Shanghai, China, during 2005 and 2006. The results show that there was a large variation in grain yield between locations and years. The realization of high yield potential for the two types of rice was closely related to the improved sink size, such as more panicles per square meter or grains per panicle. Stem and leaf biomasses were mainly accumulated from tillering stage to heading stage, and showed slow decline during grain filling. Meanwhile, some photosynthetic characters including net photosynthesis rate （Pn）, leaf area index （LAI）, specific leaf area （SLA）, fluorescence parameter （maximum quantum yield ofPSll, Fv/Fm）, chlorophyll content （expressed as SPAD value）, as well as nutrient （N, P, K） uptake were also measured to determine their variations over genotypes and environments and their relationships with grain yield. Although there were significant differences between years or locations for most measurements, SLA at tillering and heading stages, Fv/Fm and LAI at heading stage, stem biomass at heading and maturity stages, and leaf nitrogen concentration at tillering and heading stages remained little changed, indicating their pos- sible applications as selectable characters in breeding programs. It was also found that stem nitrogen accumulation at tillering stage is one of the most important and stable traits for high yield formation.     

两种女贞光合作用研究

6-9月份常绿女贞和落叶女贞的叶绿素总量和a、b无明显差异;10月份起,常绿女贞叶绿素含量高于落叶女贞,两种女贞的a/b都随发育进程增大,落叶女贞的a/b大于常绿女贞。落叶女贞落叶之前的净光合速率为负值,而常绿女贞为正值。     

不同混交模式防护林中湿地松的光合特性

在福建东山赤山防护林场对不同模式混交林中湿地松的光合特性进行野外测定,结果表明湿地松的CO2补偿点为163 μmol/mol,羧化效率为0.0171,暗呼吸速率为0.28μmol/(m2@s),光补偿点为40 μmol/(m2@s),光饱和点为1 100μmol/(m2@s);湿地松林冠下层和林冠上层的净光合作用日变化均呈双峰曲线,且林冠上层叶在光合作用过程中起着主要的作用.在营造湿地松-木麻黄的带状混交林时,为了提高湿地松的光合效能,湿地松带的行数应不少于3～4行;对稀疏木麻黄林带下套种湿地松光合效能的研究表明,在郁闭度小于0.28的稀疏林带下套种湿地松,可作为老林带更新的一种方式.     

遮荫和土壤水分对毛红椿幼苗光合特性的影响

采用3种遮荫(全光照、60%遮荫、80%遮荫)和3种土壤水分(高、中和低)处理,研究了毛红椿幼苗叶片净光合速率(Pn)、气孔导度(Co)、胞间CO2浓度(Ci)和叶绿素含量及叶面积等特性。结果表明:毛红椿净光合速率日进程曲线呈“双峰”型,高峰值出现在10:00和16:00,全光照和中度遮荫(60%)情况下有较明显的光合“午休”现象,而强度遮荫(80%)光合“午休”现象不明显。全光照下胞间CO2浓度日进程基本与净光合速率相反,当土壤含水量高时光合作用能力最强。气孔导度日变化呈下降趋势,胞间CO2浓度变化平缓,表明上午10:00以后净光合速率降低主要受非气孔限制因素的影响。在遮荫条件下,毛红椿苗木通过增大叶面积、提高叶绿素含量有效地利用较弱的光辐射,形成适应遮荫条件的生态生存对策。     

有益微生物在暗尾东方鲀养殖中应用的研究

研究结果表明噬菌蛭弧菌和光合细菌结合使用对暗尾东方鲀养殖环境具有明显的改善作用,并能有效提高暗尾东方鲀的成活率,对暗尾东方鲀也有一定的促生长作用.25 d后实验组比对照组池塘中的细菌总数少2个数量级,70 d后实验组比对照组池塘中的细菌总数少3个数量级;25 d后对照组COD为6.45 mg/L,使用噬菌蛭弧菌浓度为3、5、10 mL/m3及光合细菌皆为5 mL/m3,实验组的COD分别为4.66、4.46、4.38 mg/L;25 d后对照组NH3-N为0.53 mg/L,使用噬菌蛭弧菌浓度为3、5、10 mL/m3及光合细菌皆为5 mL/m3,实验组的NH3-N分别为0.38、0.35、0.34 mg/L;90 d后对照组NH3-N为0.52 mg/L,使用噬菌蛭弧菌浓度为3、5、10 mL/m3及光合细菌皆为5 mL/m3,实验组的NH3-N分别为0.25、0.23、0.22 mg/L;25 d后对照组硫化物为0.018 mg/L,使用噬菌蛭弧菌浓度为3、5、10 mL/m3及光合细菌皆为5 mL/m3,实验组的NH3-N分别为0.014、0.012、0.010 mg/L,90 d后对照组硫化物为0.018 mg/L,使用噬菌蛭弧菌浓度为3、5、10 mL/m3及光合细菌皆为5 mL/m3,实验组的硫化物分别为0.009、0.008、0.007 mg/L.使用噬菌蛭弧菌浓度为3、5、10 mL/m3及光合细菌皆为5 mL/m3,实验组暗尾东方鲀的成活率分别比对照组提高3.3%、7.6%、7.4%;使用噬菌蛭弧菌浓度为3、5、10 mL/m3及光合细菌皆为5 mL/m3,实验组暗尾东方鲀分别比对照组平均净增长12、17、15 g.     

过表达本氏烟基因NbPAP2对转基因植物生长发育的影响

为探究紫色酸性磷酸酶基因在本氏烟草中所发挥的生物学功能，该研究利用生物信息学软件发现本氏烟NbPAP2与拟南芥AtPAP2的氨基酸同源性达到64.2%,其具有特征性的信号肽和靶向叶绿体的C端疏水基序以及双核金属离子中心. qRT-PCR结果显示NbPAP2在植物中组成性表达，花瓣中表达量最高，测定叶片气孔导度平均提高30.5%、净光合速率平均提高23%，然而蒽酮比色法测定糖平均含量下降21%.因此，NbPAP2通过介导碳代谢促进本氏烟草花期提前、生物量提高、种子体积增大等.     

Photosynthesis of Populus euphratica and its response to elevated CO2 concentration in an arid environment

The photosynthetic characterization of Populus euphratica and its response to the elevated carbon dioxide concentration ([CO2]) were analyzed based on its net photosynthetic rate (Pn), stomatal conductance (gs), intercellular CO2 concentration (Ci), transpiration rate (Tr), and water use efficiency (WUE) at different groundwater depths measured by a portable gas exchange system (LI-6400) in the lower reaches of the Tarim River. The results showed that the elevation of [CO2] decreased the gs, and increased the Pn, Ci and WUE of P. euphratica. However, the effects of the elevated [CO2] on gs, Pn, Ci and WUE varied considerably with groundwater depth. The response of photosynthesis to rising [CO2] was stronger at the greater groundwater depth (more than 6 m) than that at the shallower groundwater depth (less than 6 m). The critical groundwater depth required to maintain the normal survival of P. euphratica was less than 6 m. When the groundwater depth increased to more than 6 m, P. euphratica encountered moderate water stress, and the plant suffered severe water stress when the groundwater depth increased to more than 7 m.     

色素分子吸收光子后电极势的变化

推导了吉布斯自由能、电动势、电极势与光子的能量之间的关系,表达式为ΔrGm=-FE=-F[φ(A+|A*)-φ(A+|A)]=0.1λ196.利用该公式计算了基态P680和P700吸收光子变成激发态P6*80和P7*00后电极势的变化,计算值为φ(P3+80|P6*80)-φ(P6+80|P680)=-1.82V,φ(P7+00|P7*00-φ(P6+700|P700)=-1.77V.计算值与测量值完全相同.另外,计算支持紫色光合细菌光系统中B875把S1态的能量转移给D.     

植物季节性变化与抗寒性关系的研究概况

综述了植物的保护酶系统、渗透调节物质及光合作用随季节性变化的规律，以及这些生理特性的季节性变化与抗寒性之间的关系，旨在为研究植物生理特性的季节性变化规律与抗寒性之间的关系提供理论参考。     

密植板栗树净光合作用生理生态的初步研究

对８年生密植板栗园“九家种”品种叶片净光合速率及其与生理，生态因子的相关关系进行了系统研究。结果表明：（１）板栗净光合速率一般为４－２０ｍｇ．ｄｍ＾－２．ｈ＾－１明显低于苹果，梨等果树；（２）Ｐｎ的日变化规律在生长初期和生长末期为单峰曲线，而在生长盛期为双峰曲线；（３）Ｐｎ的年变化进程也表现为双峰曲线，其高峰分别出现在开花期及果实速生期，Ｐｎ的年变化规律与叶绿素含量，矿质元素含量的年变化趋势相一致