“苹博一号”梨试管苗的光自养生长和光混合营养生长

研究结果表明 :“苹博一号”梨试管苗能够在无糖培养基上存活并生长 ,证明其自身具光自养能力。于培养期间增强光照或向瓶内增施CO2 气体 ,不仅能够促进试管苗的生长发育 ,而且有利于试管苗的正常分化及其光自养能力的诱导与增强。适当降低培养基中蔗糖含量 。

植物组织培养新技术:光独立培养法

该文介绍了近年来日本学者开发的光独立营养培养法 (无糖培养法 ) ,在快繁阶段 ,导入大型容器 ,去掉培养基中的糖分 ,增施 CO2 ,并对组培环境进行调控 ,为组培苗的产业化生产提供了可能性。但培养容器内环境因子对培养植物的生长及形态的影响 ,还有很多问题有待进一步研究。光独立营养培养的大型培养容器或小型设施以及机械化。

关于构建光健康理论体系的研究

光健康研究融合了半导体、照明、光学、医学、生理学、神经学等一系列学科。目前光健康研究尚未形成系统理论,不利于光健康的进一步有序发展,本文尝试以太阳光为理论基础,结合光健康研究过程中的体会和应用经验,从七个方面给出光健康理论体系的解释,为光健康研究和应用提供参考,目的是进一步完善光健康发展环境,推动光健康行业高质量发展。

生物产氢技术研究进展

Hydrogen is noted widely because it is a clean energy. Many countries in the world are studying and developing new methods for hydrogen production. Biological hydrogen production is one of such new methods with the advantages of utilizing renewable energy and wastes, and of low cost. In this paper, the characteristics of 5 modes of biological hydrogen production were summarized and compared according to hydrogen metabolic energetic. Furthermore, the molecular mechanism of biological hydrogen production by anoxygenic phototrophic bacteria was described. Finally, the newest progress of hydrogen production by anoxygenic phototrophic bacteria in the aspects of electronic donor, coupling to light energy, inhibition of ammonium, and genetic manipulation and exploiting of application system was reviewed. Fig 1, Tab 1, Ref

Effects of Different Levels of Phosphorus Nutrient on the Photosynthesis Characteristic of Rice Flag Leaf

[Objective] To provide scientific basis for high phosphorus efficiency cultivation and regulation of rice. [Method] Changbai9 （CB9） and Jijing81 （JJ81） were used as experimental materials for pot experiment, and five levels of phosphorus nutrient （ Po - P4 ） were set for each variety, the net photosynthesis rate, Chlorophyll Meter Readings （SPAD Readings）, stomatal conductance, transpiration rate, intercellular CO2 concentration, and stomatal limitation were observed and compared between five different phosphorus levels at filling stage. [ Result] The net photosynthesis rate of CB9 reached the highest at P3, and was significantly different from other treatments （P 〈0.05）;the net photosynthesis rate of groups with phosphorus of J J81 were higher than that of the control group,and reached the highest at P,. The SPAD Readings of CB9 and JJ81 all achieved the highest at P3, and stomatal conductance and transpiration rate were all at first increased then decreased with the phosphor- us increased in CB9 and JJ81. With the phosphorus increased, intercellular CO2 concentration of CB9 decreased at first and then increased, while in JJ81 the trend was inversed,but the tendency of intercellular CO2 concentration were opposite to that of stomatal limitation in both culti- vars. [ Conclusion] Appropriate adding phosphorus could improve photosynthetic characteristic of rice flag-leaf,but displayed significant genotypic difference.

植物组培设施环境调控系统的研究进展

植物组织培养是一项能获得大量同源母本基因幼苗的生物技术,又称植物克隆技术,具有其他育苗方法无法比拟的优点。但在传统的组培环境下组培苗生长缓慢、污染严重、存活率低,致使成品苗的成本过高,不利于组培苗的大规模商品化生产。目前其应用主要限于一些园艺植物,为扩大其在农业、森林等植物上的应用,必须发展一种新型的适用于离体培养小植株的自动化规模化繁殖体系。最近20年来许多学者开始重视培养环境对组培苗的生理影响并对组培微生态系统环境进行了研究。

Gas Exchange, Xylem Ions and Abscisic Acid Response to Na^+-Salts and Cl^--Salts in Populus euphratica

We investigated the osmotic stress and ion-specific effects on xylem abscisic acid (ABA), ion uptake and transport and gas exchange in one-year-old seedlings of Populus euphratica Oliv. Net photosynthetic rates (P-n) and unit transpiration rates (TRN) were both significantly decreased upon an osmotic shock caused by PEG 6000 solution (osmotic potential = -0.24 MPa) or a saline, which was applied by 50 mmol/L Na+-salts (NaNO3 : NaHCO3 : NaH2PO4 = 5 : 4 : 1, pH 6.8, osmotic potential = -0.24 MPa) or by 50 mmol/L Cl--salts (KCl : NH4Cl = 1:1, osmotic potential = -0.24 MPa). However, salt-treated P. euphratica plants maintained typically higher TRN than those exposed to PEG. Xylem ABA concentrations increased rapidly following the PEG treatment, exhibiting peaking values at 1 h, then returning to pre-stress levels, followed by a gradual increase. Similarly, both Na+-treated and Cl--treated trees exhibited a rapid rise of ABA after salt stress was initiated. Notably, salt-treated plants maintained a relatively higher ABA than PEG-treated plants in a longer term. Collectively, results suggest that osmotic stress and ion-specific effects were both responsible for salt-induced ABA in P. euphratica : the initial rapid increase of xylem ABA appears to be a consequence of an osmotic shock, whereas specific salt effects seem to be responsible for ABA accumulation later on. Compared with Cl--treated trees, a higher inhibitory effect on gas exchange (P-n and TRN) was observed in Na+-salt plants, resulting from its long-sustained ABA and higher salt concentrations in the xylem. Displacement of membrane-associated Ca2+ by Na+ and the lesser capacity in Na+ compartmentation in root vacuoles likely contribute to the high influx of Na+ and Cl- in Na+-treated plants. Xylem K+, Ca2+ and Mg2+ concentrations were elevated by external Na+ -salts and Cl--salts, suggesting that P. euphratica maintained a higher capacity in nutrient uptake under saline conditions, which makes a contribution to its salinity tolerance.

保温杯有“三不装”:牛奶、中药和茶

天气转暖,很多人出去玩会随身带一个保温杯,让自己随时能喝到温热的水或其他饮品。这种做法很好,但要记住有些饮品不能装进保温杯。

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.

Effects of salinity and nutrients on the growth and chlorophyll fluorescence of Caulerpa lentillifera

Caulerpa lentillifera is a green algae that distributes worldwide and is cultivated for food. We assessed vegetative propagation of C. lentillifera by measuring the specific growth rate （SGR） and chlorophyll fluorescence of the green algae cultured at different salinities and nutrient levels. The results indicated that C. lentillifera can survive in salinities ranging from 20 to 50, and can develop at salinities of 30 to 40. The maximum SGR for C. lentillifera occurred at a salinity of 35. Both chlorophyll content and the ratio of variable to maximum fluorescence （F_v/F_m） were also at a maximum at a salinity of 35. Photosynthesis was inhibited in salinities greater than 45 and less than 25. Both the maximum SGR and maximum chlorophyll content were found in algae treated with a concentration of 0.5 mmol/L of NO3-N and 0.1 mmol/L of PO_4-P. The photosynthetic capacity of photosystem Ⅱ （PSⅡ） was inhibited in cultures of C. lentillifera at high nutrient levels. This occurred when NO_3-N concentrations were greater than 1.0 mmol/L and when PO4-P concentrations were at 0.4 mmol/L. As there is strong need for large-scale cultivation of C. lentillifera, these data contribute important information to ensure optimal results.

Application of NaHCO_3/ DTPA Extractant-ICP Spectrometry Technique in Soil Test for Availability of Nutrients and Heavy Metals

Soil test for availability of nutrients and heavy metals is extensively served as a means for the evaluations of soil fertility, and environmental effects and phytotoxicity of pollutants in soils, and for the fertilizer recommendation in agricultural and environmental sciences. Therefore, great attention has been paid to the measurement of elemental availability in soil test.

Photosynthetic efficiency, cell volume, and elemental stoichiometric ratios in Thalassirosira weissflogii under phosphorus limitation

Nutrient limitation is known to inhibit growth and metabolism and to alter elemental stoichiometric ratios in phytoplankton. In this study, physiological changes in Thalassirosira weissflogii were measured under different dissolved inorganic phosphate (DIP) regimes in semi-continuous cultures to revisit the utility of the Redfield ratio for assessing nutrient limitation. The results showed that cell size increased with decreasing DIP availability. In the P-depleted treatment (f/2-P) the cell size was 1.48 times larger than that in the P-limited (f/100) treatment and 2.67 times larger than that in the P-saturated treatment (f/2 and f/10). The fucoxanthin to chlorophyll a ratio (Fuco/chl a) was relatively stable (about 0.3) in P-saturated cultures and was 10 times higher than that in P-limited and P-depleted cultures. During the experimental period, the photosynthetic efficiency index, ?F/Fm′, was relatively stable at ~0.50 in the P-saturated cultures, but quickly declined with decreasing DIP availability. Although cellular P content showed a significant difference between the P-saturated culture (1.6 pg/cell) and the P-limited culture (0.7 pg/cell), the N/P ratio in T. weissflogii did not show a trend with DIP availability and fluctuated slightly around 25. Our results suggest that cell division in T. weissflogii is not strictly size-gated but is probably regulated by a biochemical, and hence, an elemental stoichiometric ratio threshold, and that deviation of the cellular N/P ratio from the Redfield ratio is not a reliable indicator of algal nutrient stress.

Effects of elevated CO_2 on the photosynthesis and nitrate reductase activity of Pyropia haitanensis(Bangiales,Rhodophyta) grown at different nutrient levels

Pyropia haitanensis, a commercially important species, was cultured at two CO2 concentrations （390× 10^-6 and 700× 10^-6 （parts per million）） and at low and high nutrient levels, to explore the effect of elevated CO2 on the species under nutrient enrichment. Results show that in CO2-enriched thalli, relative growth rate （RGR） was enhanced under nutrient enrichment. Elevated CO2 decreased phycobiliprotein （PB） contents, but increased the contents of soluble carbohydrates. Nutrient enrichment increased the contents of chlorophyll a （Chl a） and PB, while soluble carbohydrate content decreased. CO2 enrichment enhanced the relative maximum electronic transport rate and light saturation point. In nutrient-enriched thalli the activity of nitrate reductase （NRA） increased under elevated CO2. An instantaneous pH change in seawater （from 8.1 to 9.6） resulted in reduction of NRA, and the thalli grown under both elevated CO2 and nutrient enrichment exhibited less pronounced reduction than in algae grown at the ambient CO2. The thermal optima of NRA under elevated CO2 and/or nutrient enrichment shifted to a lower temperature （10-15 ℃） compared to that in ambient conditions （20℃）. We propose that accelerated photosynthesis could result in growth increment. N assimilation remained high in acidified seawater and reflected increased temperature sensitivity in response to elevated CO_2 and eutrophication.

Effects of different phosphorus concentrations and N/P ratios on the growth and photosynthetic characteristics of Skeletonema costatum and Prorocentrum donghaiense

The effects of different phosphorus(P) concentrations(0.36, 3.6, and 36 μmol/L corresponding to low-, middle-, and high-P concentration groups, respectively) and nitrogen(N)/P ratios on the growth and photosynthetic characteristics of S keletonema costatum and Prorocentrum donghaiense were studied. For both species, the high-P(HP) concentration group showed the greatest algal density and highest specifi c growth rate. Changes in the maximum effi ciency of photosystem Ⅱ(F _v/F_m) were monitored under the various P and N/P conditions. The largest decrease in F _v/F_m was in the low-P(LP) group in S. costatum and in the HP group in P. donghaiense. There were high rapid light curves and photochemical quantum yields(Φ _(PSⅡ)) for S. costatum in the HP group, while the actual photosynthetic capacity was higher in P. donghaiense than in S. costatum in the MP group. Under eutrophic but relatively P-restricted conditions, P. donghaiense had higher photosynthetic activity and potential, which could cause this dinofl agellate to increasingly dominate the phytoplankton community in these conditions. Under the same P concentration and N/P ratio, P. donghaiense had a larger relative maximum rate of electron transport and higher Φ _(PSⅡ) values than those of S. costatum. These differences between P. donghaiense and S. costatum may explain the interaction and succession patterns of these two species in the Changjiang(Yangtze) River estuary from a photosynthesis perspective.

Bioactive and Some Nutritional Characteristics of Pepino （Solanum muricatum Aiton） Fruit

The some physical and chemical properties values ofpepino fruit were determined. The mineral elements （AI, B, Ca, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, P, Se and Zn） of fruit were analysed by Inductively Coupled Plasma Atomic Emission Spectrometry （ICP-AES）. Organic acid contents were analysed via HPLC equipped Ca （3,256.96 mg/kg）, K （43,465.60 mg/kg）, P （7,907.32 mg/kg） Na （1,496.13 mg/kg） and Mg （2,541.12 mg/kg） were established as major minerals in fruits. These results show that pepino fruit may be useful for the evaluation of dietary information in important food crops.

Temporal and spatial distribution of virioplankton in large shallow freshwater lakes

Virioplankton dynamics at seven sample sites(from two freshwater lakes) with different trophic states were monitored over the period of a year.Water was sampled monthly from August 2004 to July 2005,and the abundances of viruses and bacteria were measured using direct epifluorescence microscopy counting.Results indicated that both natural and anthropogenic factors could influence the distribution of virioplankton.Temporally,viral abundance was significantly correlated to bacterial density and water temperature.Spatially,viral abundance was significantly correlated to trophic state.This in turn indicated that viral abundance was directly dependant on host abundance in eutrophic lakes,while trophic state and temperature could drive the distribution of virioplankton.The virus-bacteria ratio was significantly lower in less productive water-bodies.The result implied that the control of virioplankton on their hosts may change according to the host density.

Photosynthetic Carbon Gain, Allocation and Resources-Use Efficiency in Invasive Eupatorium Adenophorum and Its Native Congener E. Japonicum under Different Light and Nutrient Conditions

Invasion is often facilitated by high resources availabilities and suppressed under low resources habitats. However, a number of invasive plants can successfully establish and dominate in resource-poor and （or） the understory of closed forests, indicating the plant＇s performances are habitats-dependent and species-specific. It is therefore necessary to explore the ecophysiological characteristics associated invasiveness for one invasive species across multiple resources availabilities whilst taking the relatedness into these comparative studies. In this study, invasive Eupitorium adenophorum and its native congener E. japonicum grew under different resource gradients in terms of light levels and soil nitrogen additions to identify the functional significance morphological and physiological traits associated closely with invasion and to examine their comparative responses. Photosynthetic carbon gain, biomass allocation and resource-use efficiency are evaluated in this pot experiment. Across treatments, E. adenophorum exhibited consistently higher values for most of the morphological variables including plant stature, relative growth rate （RGR）, leaf root ratio （LRR）, leaf area ratio （LAR）, total leaf area, and lower root： shoot ratio （RSR）. Significantly higher Pmax corresponded with higher photosynthetic nitrogen use efficiency （PNUE） and photosynthetic energy use efficiency （PEUE） especially in low light and （or） unfertile condition. Higher Gs and Pmax but lower photosynthetic water use efficiency （WUE） indicated the trade-off relationship between WUE and PNUE for E. adenophorum. Final biomasses were higher for E. adenophorum in nutrient and（or） light limited conditions, in which higher leaf construction cost（CC） compared with E. japonicum could be over-compensated by its significantly higher assimilation rates. The effects of light levels on these plant attributes were stronger than soil nutrient contents. The responses of these two congeneric species to light and nitrogen availabilities were similar, but the differences were magnified in resources limited conditions, indicating the better performancer at acquiring and at using limited resources of E. adenophorum over its co-occurring native flora. Our study presented the distinctive advantages of E. adenophorum in resources-poor environments, indicating conventional strategy of managing resources levels to control the invasion and expending of exotic species may not be as effective as expected.

Composition of Pig Manures and Wastewaters under the Gan Qing Fen System in China

A large scale pig farm located in the North West of Beijing that applies the gan qing fen manure management system was selected and a continuous sampling of manures and wastewaters was performed from June to October 2009. Samples were collected once a week based on the pig production cycle, namely gestation, farrowing, weaning and fattening. Analysis of nutrients and heavy metals were determined by means of Inductively Coupled Plasma Atomic Emission Spectroscopy （ICP）. Total Nitrogen （TN） was determined by the Kjeldahl method. The main results showed that pig manures were characterized by high nutrients and heavy metals contents that might be due to the solid fraction separation from the liquid fraction under the gan qing fen manure management system. Further, piggery wastewaters were characterized by very low concentrations of nutrients and heavy metals as result of their dilution with flushing water mainly used for cleaning the pigsties. Manure and wastewaters samples from weaning pigs contained the highest concentrations of nutrients and heavy metals that could be due to high supplementation rates of these minerals in the weaner diets. In general, it seems that the manual daily collection of pig manures in the gan qing fen system is an efficient practice in order to maintain nutrient contents in pig manures but the use of flushing water should be reduced as it can lead to further environmental pollution.

Effect of Spraying Liquorices Root Extract on Vegetative Growth, Chemical Characters and Photosynthetic Pigments of Chrysanthemum （Chrysanthemum morifolium L.） Grown under Salt Stress

This experiment was conducted in Horticulture Department, School of Plant Production, Faculty of Agriculture and Forestry, University of Duhok, Iraq in 2010 on Chrysanthemum plants, in order to mitigate the adverse influence of salinity by the use of liquorice root extract and study its effect on vegetative growth, chlorophyll content in leaves from chlorophyll and assistant pigment, carbohydrate and starch. Subsequently, the trail consisted of three levels of salinity （0, 4 and 8 ds m^-1） and three concentrations of the liquorice root extract 0, 2.5 and 5 g L^-1. Results showed that salinity （4 ds m^-1） rate caused significant increases in certain vegetative characteristics （branches number, plant height, leaves number and leaf area）, photosynthetic pigments （Chl a, Chl b, total chlorophyll, a-carotene, β-carotene, zeaxanthin, astaxanthin）, fresh shoot weight, fresh root weight, shoot dry weight, root dry weight, shoot： root ratio, carbohydrate dry weight percentage and starch percentage as compared to untreated check. However, increasing salinity rate to 8 ds m^-1 resulted in substantial reductions in all above mentioned Waits. Treatment with liquorices root extract, in particular, 5 g L^-1 manifested a potent capability in ameliorating the salinity negative effects in terms of vegetative and photosynthetic pigments aspects.

Sewage Sludge： A Sustainable Source for Plant Nutrient

Sludge production is an avoidable problem arising from the treatment of wastewater. The sludge remained after municipal wastewater treatment contains considerable amounts of various contaminants and if is not properly handled and disposed, it may produce extensive health hazards. On the other hand, this sludge has benefit for plants and soils. Sludge samples were collected over a 12 month period from sewage treatment plants （STP＇s）, i.e, Khairathabad and Meeralam Tank, Hyderabad, India and analyzed for C, H, N, S by elementar analyzer, P, K, Ca, Mg by spectrophotometer and heavy metals like Zn, Pb, Ni, Cu, Cd by atomic absorption spectrophotometer. The sludge contained approximately 50% organic matter and 1-4% inorganic carbon. Organic and inorganic carbon, organic nitrogen, inorganic phosphorous, Ca and Mg were found to be present in sludge at a relatively constant concentration with respect to sampling time. Inorganic N, organic P, K, and all metals were found to be quite variable with time when sludge produced from different STP＇s.