Combining Ability Analyses of Net Photosynthesis Rate in Pepper (Capsicum annuum L.)

In perspective of breeding high-yield hybrid pepper varieties, combining ability analysis of net photosynthesis rate at different phases of flowering and fruit setting in pepper was made with 15 cross combinations from 6 parents by （1/2） n （n- 1） diallel crosses. There are relatively large differences not only in general combining ability （GCA） effect among different parents and at different phases of flowering and fruit setting, but also in specific combining ability （SCA） effect among different hybrids. There are relatively large GCA effects in late parents but relatively less GCA effects in early parents. No obvious laws have been found in the relationship between SCA effects and maturity of hybrids. Variances of SCA are larger than those of GCA. Heritability is less but influence of environment is larger. Correlation analysis of combining ability between net photosynthesis rate and agronomic character or resistances to main diseases has showed that correlation coefficients of GCA are relatively large at the medium phase and the late phase of flowering and fruit setting. Net photosynthesis rate is more relative to leaf characters and fruit characters. Correlation coefficients of SCA are relatively large at the early phase and the late phase of flowering and fruit setting. Net photosynthesis rate is more relative to leaf characters and plant characters at the early phase but to plant characters and fruit characters at the late phase. Correlation coefficients of SCA between net photosynthesis rate and resistances to main diseases are larger than those of GCA. The combining abilities of net photosynthesis rate at different phases of flowering and fruit setting are positively correlated with those of yield per plant. The combining ability is an important parameter of breeding of high photosynthesis hybrid pepper varieties.

Canopy Net Photosynthesis Rate of a Mongolian Oak (<i>Quercus mongolica</i>) Forest Estimated by Field Experimental Data

The canopy net photosynthesis rate of Mongolian oak (Quercus mongolica) tree species that are dominant in East Asia and Korea is estimated with empirical models derived from field experimental data obtained from the Nam-San site in Seoul, Korea for the growing period from early May to late October in 2010. The empirical models include the attenuation function of photosynthetic photon flux density (PPFD) (r2 = 0.98-0.99, p r2 = 0.99, p < 0.001) derived from the measured data at several levels within the canopy. The incident PPFD at each level within canopy significantly varies diurnally and seasonally due to the seasonal variation of the total plant area index (TPAI = leaf area index + wood silhouette area index) and the light shielding effect of light path-length through the canopy in association with the variation of solar elevation angle. Consequently, a remarkable seasonal variation of the total canopy net photosynthesis rate of Q. mongolica forest stand is found for its growing period. The PPFD exceeding 1000 μmol m-2·s-1 is found to cause the decrease of net photosynthesis rate due to the thermal stress in the early (May) and late (September) growing period. During the whole growing season, the estimated total canopy net photosynthesis rate is found to be about 3.3 kg CO2 m-2.

SIMPLE SIMULATION OF THE ANNUAL VARIATION OF THE SPECIFIC PHOTOSYNTHESIS RATE IN JIAOZHOU BAY

A simple diagnostic simulation of the annual cycling of the surface specific photosynthesis rate (SPR) in Jiaozhou Bay is described in this paper. Light intensity, temperature and nutrients (nitrate + ammonia, phosphate) were considered as main factors controlling photosynthesis of phytoplankton and were introduced into the model by different function equations. The simulated variation of specific photosynthesis rate coincided with the measured data. Analysis of the effect of every factor on photosynthesis indicated that the variation of photosynthesis rate was controlled by all these three factors, while temperature showed good correlation with SPR as measurement showed. This diagnostic simulation yielded the values of some parameter relating with the photosynthesis in Jiaozhou Bay.

五个杨树品种生长、光合生理及根尖离子流速特性比较分析

通过比较不同品种杨树(Populus)的生长、光合生理及根尖离子流速特性差异,为速生适应性强品种的早期选育提供参考。以渤丰3号杨(P.×euramericana‘Bofeng 3’)、渤丰1号杨(P.×euramericana‘Bofeng 1’)、西雄1号杨(P.×euramericana‘Xixiong 1’)、中雄7号杨(P.×euramericana‘Zhongxiong 7’)和中雄4号杨(P.deltoides×P.suaveolens cl.‘Zhongxiong 4’)5个杨树品种1年生苗为研究对象,于正常培养条件下的试验开始和试验结束(30 d)时分别测定株高、地径等生长指标,并于10、20、30 d时分别测定幼苗的叶片数量、单叶面积、叶长、叶宽、瞬时净光合速率(P_(n))、胞间CO_(2)摩尔浓度(C_(i))、气孔导度(G_(s))、蒸腾速率(T_(r))、叶绿素相对含量以及根尖K^(+)、Ca^(2+)、H^(+)流速等指标,经过30 d的正常管理,5个品种的株高生长量之间的差异达到显著水平,由高到低依次为中雄4号杨、西雄1号杨、渤丰3号杨、中雄7号杨、渤丰1号杨;其中光合特性指标和蒸腾速率渤丰1号杨均表现为最大,中雄4号杨均表现为最小,但是中雄4号杨的单叶面积((57.49±2.37)cm^(2))、总叶面积((1721.10±28.59)cm^(2))、单株净光合速率((17863.10±910.21)μmol·m-2·s-1)和水分利用率((3.15±0.06)μmol·mmol^(-1))均表现为最大,且K^(+)外排流速最慢,为(62.68±0.45)pmol·cm^(-2)·g^(-1),Ca^(2+)内流流速最快,为(-74.24±1.29)pmol·cm^(-2)·g^(-1),而渤丰1号的单株净光合速率((8539.70±164.64)μmol·m-2·s-1)和水分利用率((2.64±0.07)μmol·mmol^(-1))最小,且K^(+)外排流速((130.81±1.71)pmol·cm^(-2)·g^(-1))最快,Ca^(2+)内流流速((-34.43±0.84)pmol·cm^(-2)·g^(-1))最慢。综上所述,5个杨树品种中,中雄4号杨总叶面积、单株净光合速率、水分利用率最高,蒸腾速率最小,根尖K^(+)外排流速最慢,Ca^(2+)内流流速最快,植物体内K^(+)、Ca^(2+)离子含量最多,H^(+)最活跃,株高生长表现最好,可能具有潜在的较强环境适应能力,适宜种植的范围更广。

不同偏置条件下NPN双极晶体管的电离辐照效应

对NPN双极晶体管进行了不同剂量率、不同偏置条件下的电离辐射实验。研究结果表明:同一剂量率辐照时,无论是低剂量率还是高剂量率,辐照损伤均是基-射结反向偏置时最大,零偏置次之,正偏置最小。NPN双极晶体管在3种偏置下均可观察到明显的低剂量率辐照损伤增强(ELDRS)效应,且偏置条件对ELDRS效应很明显,表现为基-射结正向偏置ELDRS效应最为显著,零偏次之,反向偏置最次。对出现这一实验结果的机理进行了探讨。

不同基区掺杂浓度NPN双极晶体管电离辐照效应

对相同工艺制作但基区掺杂浓度不同的国产NPN双极晶体管,在不同剂量率条件下进行60Coγ辐照效应和退火特性研究。结果显示,晶体管基区掺杂浓度不同,对高、低剂量率的辐照响应也不相同,低基区掺杂浓度的晶体管辐照损伤明显高于高基区掺杂浓度的晶体管。

变温辐照加速评估方法在不同工艺的NPN双极晶体管上的应用

对6种不同工艺的NPN双极晶体管进行了高、低剂量率及变温辐照的^(60)Coγ辐照实验。结果显示,6种工艺的NPN双极晶体管均有显著的低剂量率辐照损伤增强效应。而变温辐照损伤不仅明显高于室温高剂量率的辐照损伤,且能很好地模拟并保守地评估不同工艺的NPN双极晶体管低剂量率的辐照损伤。对实验现象的机理进行了分析。

不同剂量率下NPN管和NMOSFET管的电离辐照效应

研究了 NPN双极晶体管和 NMOSFET在不同剂量率环境下的电离辐照效应。研究表明 ,NPN管在低剂量率辐照下 ,电流增益衰降更为显著 ,且具有真正的剂量率效应 ;而 NMOS管在低剂量率辐照下产生的阈电压负向漂移比高剂量率辐照时小 ,其辐照效应是时间相关效应 ,而非真正的剂量率效应。

扁核木不同直径茎干的光合生理特征

植物的绿色茎干能在叶片缺失时有效地利用阳光进行光合作用,为植物的生长发育提供额外的能量来源,使其更好地适应极端环境。本研究以分布于西南地区具有绿色茎干的植物——扁核木为对象,比较了扁核木不同直径茎干的光合特性及其与叶绿素含量之间的差异,为扁核木的育种和高效栽培提供依据。结果显示:(1)扁核木茎干具有较强的光合能力,且与叶绿素含量存在显著相关性;(2)不同直径的茎干叶绿素含量和光合能力存在差异,随着扁核木茎干直径的增加,叶绿素含量、净光合速率、光补偿点和光饱和点呈现逐渐下降的趋势,但扁核木不同直径的茎干净光合速率均较高。研究表明:茎干的光合作用功能有助于扁核木在早春无叶期间完成开花的生理过程,提高了其对极端环境的适应性。

Influence of O-O formation pathways and charge transfer mediator on lipid bilayer membrane-like photoanodes for water oxidation

Inspired by the function of crucial components in photosystemⅡ(PSⅡ),electrochemical and dyesensitized photoelectrochemical(DSPEC)water oxidation devices were constructed by the selfassembly of well-designed amphipathic Ru(bda)-based catalysts(bda=2,2'-bipyrdine-6,6'-dicarbonoxyl acid)and aliphatic chain decorated electrode surfaces,forming lipid bilayer membrane(LBM)-like structures.The Ru(bda)catalysts on electrode-supported LBM films demonstrated remarkable water oxidation performance with different O-O formation mechanisms.However,compared to the slow charge transfer process,the O-O formation pathways did not determine the PEC water oxidation efficiency of the dyesensitized photoanodes,and the different reaction rates for similar catalysts with different catalytic paths did not determine the PEC performance of the DSPECs.Instead,charge transfer plays a decisive role in the PEC water oxidation rate.When an indolo[3,2-b]carbazole derivative was introduced between the Ru(bda)catalysts and aliphatic chain-modified photosensitizer in LBM films,serving as a charge transfer mediator for the tyrosine-histidine pair in PSⅡ,the PEC water oxidation performance of the corresponding photoanodes was dramatically enhanced.

不同灌溉方式对西北干旱区紫花苜蓿生产性能的影响

为了明确紫花苜蓿品质形成差异的水分生理特征,探索因地制宜、节水高效的灌溉模式,以河西地区为例,以不灌水(CK)为对照,对比分析了常规畦灌(M)、交替灌溉(T)和隔沟灌溉(G)等3种不同灌溉方式分别在灌底墒水、越冬水、返青水和现蕾水不同灌溉量下对“三得利”紫花苜蓿产量和品质的影响。结果表明:(1)不同灌水方式下株高与灌水次数呈正相关,分支数与灌水量呈负相关;交替灌溉在灌底墒水、越冬水、返青水和现蕾水条件下株高三茬平均值最高为91.92 cm。(2)各灌水模式下,紫花苜蓿净光合速率、蒸腾速率随灌水量的增大表现出增高的趋势,其中交替灌溉的净光合速率随灌水量的增大提高了15.64%,且均高于常规畦灌和隔沟灌溉在同等灌水量下净光合速率。(3)不同处理紫花苜蓿的产量随灌水量的增加而增加,漫灌处理紫花苜蓿的三茬总产量显著高于交替灌溉与隔沟灌溉在相同灌水量下苜蓿产量,在灌底墒水、越冬水、返青水和现蕾水条件下三茬总产最高达49447.6 kg/hm^(2)。(4)不同灌水方式紫花苜蓿粗蛋白含量和中性洗涤纤维含量显著高于无灌水(CK)处理,且随着灌水量的增加有不同程度的提高。河西地区地处干旱和半干旱区,以节水灌溉的角度出发,可以选择交替灌溉灌底墒水、越冬水、返青水和现蕾水的灌溉模式能够在保证高产的同时,达到节水的目的。

施氮量对强筋小麦光合、产量、蛋白质含量和加工品质的影响

为探究冀东地区强筋小麦适宜施氮量,以强筋小麦石优20号和中麦998为材料,通过大田试验设置0 kg·hm^(-2)(N_(0))、180 kg·hm^(-2)(N 180)、210 kg·hm^(-2)(N 210)和240 kg·hm^(-2)(N 240)4个施氮水平,分析了施氮量对强筋小麦光合、产量、蛋白质含量和加工品质的影响。结果表明,与N_(0)处理相比,施氮后石优20号和中麦998的产量均在N 240处理下增加显著,增幅分别为3.20%和13.95%。随施氮量的增加,小麦旗叶叶绿素含量和光合参数均呈先升后降趋势,且在花后15 d达到最大值。施氮对F v/F m影响较小,对ΦPSⅡ影响较明显。旗叶、籽粒内硝酸还原酶和谷氨酰胺合成酶均随施氮量的增加呈先升后降趋势。增施氮肥后籽粒蛋白组分中清蛋白、球蛋白比例下降,醇溶蛋白、谷蛋白比例上升,各组分含量在N 210处理下均最高。面筋含量、沉降值、形成时间和稳定时间均随施氮量的增加先升后降。这说明增施氮肥可改善強筋小麦植株的光合特性,进而提高产量,同时增加植株体内氮代谢相关酶活性和籽粒蛋白质含量并改变蛋白质组分所占比例,有效改善加工品质。本试验条件下,210 kg·hm^(-2)施氮量下,小麦产量和品质较优,该施氮量可作为冀东平原强筋小麦栽培的最佳施氮量。

Effect of temperature,salinity and irradiance on growth and photosynthesis of Ulva prolifera

Intensive Pyropia aquaculture in the coast of southwestern Yellow Sea and its subsequent waste, including disposed Ulva prolifera, was speculated to be one of the major sources for the large-scale green tide proceeding in the Yellow Sea since 2007. It was, however, unclear how the detached U. prolifera responded and resumed growing after they detached from its original habitat. In this study, we investigated the growth and photosynthetic response of the detached U. prolifera to various temperature, salinity and irradiance in the laboratory. The photosynthetic rate of the detached U. prolifera was significantly higher at moderate temperature levels（14–27℃）and high salinity（26–32）, with optimum at 23℃ and 32. Both low（14℃） and highest temperature（40℃）, as well as low salinity（8） had adverse effects on the photosynthesis. Compared with the other Ulva species, U. prolifera showed higher saturated irradiance and no significant photoinhibition at high irradiance, indicating the great tolerance of U. prolifera to the high irradiance. The dense branch and complex structure of floating mats could help protect the thalli and reduce photoinhibition in field. Furthermore, temperature exerted a stronger influence on the growth rate of the detached U. prolifera compared to salinity. Overall, the high growth rate of this detached U. prolifera（10.6%–16.7% d^–1） at a wide range of temperature（5–32℃） and salinity（14–32） implied its blooming tendency with fluctuated salinity and temperature during floating. The environmental parameters in the southwestern Yellow Sea at the beginning of green tide were coincident with the optimal conditions for the detached U. prolifera.

Photosynthesis,Metabolite Composition and Anatomical Structure of Oryza sativa and Two Wild Relatives,O.grandiglumis and O.alta

Photosynthesis, enzyme activities and metabolite pools associated with primary carbon metabolism in leaves were studied in O. grandiglumis and O. alta （wild relatives of rice which produce high biomass） versus O. sativa （a japonica cultivar and a indica-japonica hybrid） to assess their potential for identifying traits which might be utilized to enhance rice productivity. The wild relatives had higher rates of photosynthesis on a fresh weight basis, and higher water use efficiency than the O. sativa lines. There were no striking differences in activities of a number of key enzymes in carbon and nitrogen metabolism between the wild relatives and cultivated rice lines. Along with higher rates of photosynthesis on a fresh weight basis, the leaves of the two wild species had higher nitrate content, higher levels of starch, glucose and fructose, and higher levels of organic acids （malate, succinate and acetate）, compared to the O. sativa lines. The results suggested that O. grandiglumis and O. alta have differences in physiology and primary metabolism which might be exploited to improve growth and productivity of cultivated rice.

CO_2, H_2O exchange and stomatal regulation of regenerated Camptotheca acuminata plantlets during ex vitro acclimatization

For finding the changes in CO2, H20 exchange and their stomatal regulation during ex vitro acclimatization of regenerated Camptotheca acuminata plantlets, the net photosynthesis rate （Pn）, respiration rate （Ro）, light compensation point （Lc） and light saturation point （Ls）, transpiration rate （Tr）, stomatal conductance （gs） and water use efficiency（WUE） were measured during 37 days of ex vitro acclimatization. The results showed that Pn sharply increased until 29 days, then slightly decreased. A substantial decrease in Lc and a substantial increase of Ls in the former two weeks were observed, indicating the light regime enlargement for effective leaf photosynthesis. Tr and gs abruptly decreased during the first week then linearly increased until 29days ex vitro acclimatization, reflecting the strong regulation effect of stomata on water changes of ex vitro acclimating plantlets. Stomatal regulation effect on CO2 exchange was different from that on water exchange, i.e. P, was almost independent of gs during the first week, while P. was significantly correlated with gs thereafter （i.e. dual patterns）. Different from dual patterns of gs-Pn relation, the Tr monotonously linearly increased with gs. Furthermore, WUE was almost independent on gs during the first week, while a marked decreasing tendency with gs was found thereafter. At the beginning of the acclimatization, WUE was mainly determined by photosynthetic capacity, while transpiration becomes a main determinant factor for WUE from 7 to 37 days＇ acclimatization.

施氮量对优质稻“福香占”光合特性、产量及品质的影响

【目的】烟稻轮作生产模式可以有效改善土壤生态,促进农业增效、农民增收。氮肥是影响水稻生长发育的关键因素,为明确优质稻“福香占”在福建烟后稻区的最佳氮肥施用量,充分发挥其优质、高产特性,【方法】本研究设置CK(0)、N1(51.75)、N2(103.5)、N3(155.25)、N4(207 kg/hm^(2))5个氮肥(以纯氮计)水平,在大田环境下,分析“福香占”光合特性、田间产量及其构成因素、稻米品质、香味等方面的变化。【结果】随施氮量增加,“福香占”生育期逐渐延长,叶片SPAD值、净光合速率、叶绿体大小、叶片中蔗糖和淀粉含量均上升,N3或者N4达到最高。两年穗总粒数和田间产量均是N2最高,结实率、千粒重随施氮量增加而降低。稻米加工品质N2处理表现最好,外观品质和食味品质受氮肥水平影响不显著。蛋白质含量随氮肥量升高而增加,峰值黏度、热浆黏度、最终黏度、崩解值均随氮肥量增加而降低,消减值升高。N2处理糙米香味物质2-乙酰-1-吡咯啉(2-AP)的含量最高。【结论】氮肥处理促进了“福香占”的光合作用,但过量氮肥使得植株贪青迟熟,结实率和产量下降。施氮量为103.5 kg/hm^(2)(N2)时,“福香占”高产和优质协调,香味物质积累多。本研究为“福香占”进一步在福建烟后稻区推广应用及优质稻产业高质量发展奠定了基础。

Research Progress and Prospect on the Effects of Abiotic Stress on Plant Photosynthesis

Photosynthesis is the basis of plant growth and development as well as the existence of the biological world. Photosynthesis is of great theoretical and practical significance. In this paper, the effects of temperature, drought, salt, light and other abiotic stress factors on plant photosynthesis were reviewed.

Research Progress and Prospect on the Influencing Factors of Photosynthesis in Higher Plants

Photosynthesis plays an important role in organic synthesis, solar energy storage, and environmental protection. Photosynthesis is of great theoretical and practical significance. In this paper, the main factors affecting photosynthesis of higher plants, including light, water, temperature, CO2, mineral elements and plant genotypes, were briefly reviewed and summarized, and the development prospect of photosynthesis was prospected.

基于三维模型的NPN双极型晶体管电离辐射效应仿真模拟

为更加迅速可靠地评估星用双极型晶体管抗电离辐射损伤性能,建立了三维NPN晶体管模型,并对其电离辐射效应进行了数值模拟。仿真计算了电离辐射在晶体管中产生的氧化物正电荷陷阱以及界面陷阱,以此模拟不同总剂量、剂量率电离辐照对晶体管的损伤;以漂移扩散模型计算了晶体管典型性能的响应,验证了晶体管的总剂量效应和低剂量率损伤增强效应。结果表明晶体管对电离辐射敏感的区域位于基区和发射结区附近的Si/SiO_(2)界面,从Gummel曲线提取的归一化增益发现,电离辐射损伤可能使晶体管增益降低50%以上,这对晶体管性能影响很大。该方法可以在降低成本、缩短周期的前提下,为晶体管抗电离辐射可靠性评估提供合理的技术支撑和可借鉴的理论数据。

Photosynthesis of Submerged and Surface Leaves of the Dwarf Water Lily(Nymphoides aquatica)Using PAM Fluorometry

Dwarf Water Lilies Nymphoides aquatica(J.F.Gmel)Kuntze have floating and submerged leaves.Some submerged aquatic vascular plants have a form of CAM(Crassulacean Acid Metabolism)called Submerged Aquatic Macrophyte(SAM)metabolism.Blue-diode based PAM technology was used to measure the Photosynthetic Oxygen Evolution Rate(POER:1O_(2)≡4e^(-)).Optimum Irradiance(E_(opt)),maximum POER(POER_(max))and quantum efficiency(α_(0))all vary on a diurnal cycle.The shape of the POER vs.E curves is different in seedling,submerged and surface leaves.Both E_(opt) and POER_(max) are very low in seedling leaves(E_(opt)≈104μmol photon m^(-2) s^(-1),PPFD;POER_(max)≈4.95µmol O_(2) g^(-1) Chl a s^(-1)),intermediate in mature submerged leaves(E_(opt)≈419µmol photon m^(-2) s^(-1) PPFD,POER_(max)≈38.1µmol O_(2) g^(-1) Chl a s^(-1))and very high in surface leaves(E_(opt)≈923µmol photon m^(-2) s^(-1) PPFD,POER_(max)≈76.1µmol O_(2) g^(-1) Chl a s^(-1)).Leaf titratable acid(C4 acid pool)is too small(≈20 to 50 mol H+m^(-3))to support substantial SAM metabolism.Gross daily photosynthesis of surface leaves is≈3.71 g C m^(-2) d^(-1) in full sun and as much as 1.4 gC m^(-2) d^(-1) in shaded submerged leaves.There is midday inhibition of photosynthesis.