Effects of Light and Temperature on the Expression of the Lhcb2 Gene in Pea

An approximately 800 bp cDNA ( Lhcb 2) encoding light_harvesting chlorophyll a/b_binding protein complex (type Ⅱ) was cloned from the seedling of pea ( Pisum sativum L.) with RT_PCR method. Southern blotting using special probe demonstrated that there existed one copy of Lhcb 2 in pea genome. RT_PCR and Northern blotting revealed the expression of Lhcb 2 which was regulated by light in a time_dependent expression manner. The Lhcb 2 gene didn't express untill 2 h after irradiated with white light. Low temperature (4 ℃) also affected the Lhcb 2 gene by decreasing half of its expression under 25 ℃.

Comparative Study of Photosynthetic and Fluorescence Characters of the Grape under High Temperature and High Light in Turpan

[Objective] The aim was to explore the photosynthetic characteristics of Turpan grapes under high temperature and strong light conditions. [Method] Using six grape varieties as experimental materials, the photosynthesis and fluorescence parameters of the grape varieties under high temperature and high light were determined. [Result] The results showed that Thompson Seedless showed strong selfprotection ability on the photosynthetic mechanism in the adversity, and lower photo inhibition on photosynthesis under high temperature and high light than other varieties in which Crimson Seedless was second place. Otherwise the damage on photosynthetic mechanism of Kyoho and Red Globe under the adversity environment is more dipper than the other varieties, and poor self-protection ability. [Conclusion]Thompson Seedless and Crimson Seedless had a strong adaptability for high temperature and strong light. But the adaptability of Kyoho and Red Globe were relatively poor.

Effect of Low Temperature and Sparse Light Conditions on Cold Tolerance of Different Rice Lines at Seedling Stage

Low temperature and sparse light in early spring is one of the factors causing reduction for rice production. So it is important to develop cold tolerance cultivars. In the present study, cold tolerance characters of 36 parents and 423 rice lines from 68 hybrid groups were investigated at seedling stage under low tempera- ture and sparse light conditions in field. There were 10 parent accessions with strong cold tolerance of level 1. Among them, 3 were common wild rice accessions; 4 were japonica rice cultivars; 2 were indica rice; 1 was offspring from hybrid be- tween indica and japonica.There were 33 lines with strong cold tolerance of level 1 from the hybrid groups of common wild rice,and 15 from the hybrid groups of IRBB5, and only 3 from the hybrid groups of BPHR96. There were abundant cold tolerance resources in rice germplasm. It was feasible to develop cold tolerance cul- tivars from the hybrids among common wild rice, japonica cultivars and indica culti- vars.

Characteristics and Trend Variation of Light,Temperature and Water Resources in Dongling District of Shenyang Province in Recent 49 Years

The meteorological data of light,temperature and water during 1961-2009 were selected to analyze the trend variation of climatic resources and provide the basis for developing and utilizing local climate resources.The results indicated that light resource presented the decreasing tendency in Dongling District,annual radiation reduced by 528 MJ/m2,and annual sunshine duration decreased by 333 h.The heat resource presented the increasing tendency,the average annual temperature increased by 1.04 ℃,and active accumulated temperature increased by 228 ℃.The general trend of annual precipitation declined slightly,precipitation resource during every age changed slightly and would tend to be stable.

Effects of Light and Temperature on Uptake andDistribution of Nitrogen, Phosphorus and Potassiumof Cucumber in Solar Greenhouse

The influence of light and temperature conditions inside solar greenhouse of winter-spring and autumn-winter crop in northern China on uptake and distribution of nitrogen. phosphorus and potassium of cucumber was studied. The results showed that plant root development and uptake and distribution of N, P and K benefited more from inside light and temperature changes in winter-spring crop. Root volume and root activity increased more rapidly in winter-spring than in autumn-winter. Uptake of total N, P2O5 and K2O increased with plant development in winter-spring, and declined in autumn-winter crop. Distribution of total N, P2O5 and K2O at different part of cucumber at fruit bearing stage was significantly influenced by inside light and temperature of solar greenhouse. Total N, P2O5 and K2O were mainly distributed to leaves and stems at early stage, and increasingly to fruits after fruit bearing.

Effects of Light and Temperature Factors on Biomass Accumulation of Winter Wheat

[Objective] The study aimed to discuss the influence of light and temperature factors on biomass accumulation of winter wheat at each growth stage and changes in biomass of each organ. [Method] Based on the observation data from Xifeng Agrometeorological Experiment Station of Gansu Province, including phenophase and yield factors of winter wheat in 1981 -2008, biomass at three-leaves, overwintering, jointing, heading, milky maturity, and maturity stages in 1995 -2008, and meteorological data in 1995 -2008, the variation patterns of the biomass accumulation and the influence of TEP （thermal effectiveness photosynthetically active radiation） on the biomass of winter wheat at every growth stage were ana- lyzed. [Result] The biomass accumulation of winter wheat in the whole growth period presented ＂S＂ curve, with the maximum value from heading to milky maturity stage. Since 1981, TEP from heading to milky maturity stage increased with a rate of 3. 314 MJ/（m2 · a）, and the changing curves of TEP at other stages were like parable curves. TEP from turning green to jointing stage and from milky maturity to maturity stage had a higher value in the 1990s and a lower val.ue in the 1980s and early 21st century, while that from jointing to heading stage had a lower value in the 1990s but a higher value in the 1980s and early 21st century. There was a significant correlation between TEP at each growth stage and the actual yield. LAI （leaf area index） at each development stage also had a significant correlation with the utilization rate of TEP at corresponding stage. When LAI at jointing and heading stages increased by I, the utilization rate of TEP correspondingly increased by 0. 049 and 0.259 g/MJ respectively. [ Conclusion] The research could provide theoretical references for the scientific planting and management of winter wheat in future. Key words Light and temperature factors; Winter wheat; Biomass; Influence; China

Ambient Light Alters Gene Expression Pattern of Enzymes and Transcription Factors Involved in Phenylpropanoid Metabolic Pathway in Potato under Chilling Stress

[Objective] Expressions of key enzymatic genes involved in phenyl-propanoid metabolic pathway in potato and StR2R3-MYB and StTGA transcripters were investigated in the present study. [Method] The primitive cultivar Yan was the materials for replicated trials and total RNA extracted from tissues of seedlings. Re-al-time florescent quantification PCR, multiple intervals of air temperature, light-il umi-nation and time-duration were factors of treatments in the experiment. Data on gene expressions were obtained and proceed to asses and compare effects based on statistical analysis. [Result] The results showed negative correlations between tem-perature degrees and expressions of StPAL, StDFR and StR2R3-MYB genes but not StTGA. Positive correlations, however, were derived between those of StCHS, StDFR and StR2R3-MYB and light-intensity. Significant interactive effects between expressions of StPAL and StDFR and treatments, light intensity and temperature degree, along the phenylpropanoid pathway were observed. Transcription regulator of StR2R3-MYB showed significant positive effect on the expression of StCHS of potato. StTGA transcription factor, on the other hand, gave significant negative ef-fects on the expression of StDFR. [Conclusion] Results from present study reveal the role of environmental factors and complicate interactions between such condi-tions as temperature-light il umination and mRNA function of target genes.

Study on the Variation of Ningxia Climate Productive Potential under the Returning Farmland to Forestland and Grassland Background

The key zones of returning farmland to forestland and grassland in Ningxia were studied. By using the ＂stepwise revised method＂,the climate productive potential,light and temperature productive potential in the zone in recent 50 years were counted. The light and temperature productive potential of corn in Ningxia irrigated area,the central arid zone and the southern mountain area presented the linear increase trend. But when considered the climate productive potentials of light,temperature and water,the numerical value was very low because of the scarce rainfall,and no agriculture without the irrigation. The light and temperature productive potential,climate productive potential of winter wheat in the central arid zone had no significant trend,but the variation range of climate productive potential was very big. The light and temperature productive potential of winter wheat in the southern mountain area had no significant variation trend,and the climate productive potential presented the weak decline trend. It illustrated that the productive of winter wheat was greatly restricted by the water content. By using the meteorological factor data which were simulated by RegCM3-WOFOST/LINGRA coupled model,the future climate productive potentials of winter wheat in the central south of Ningxia was counted. They both presented the weak increase trend. It illustrated that the climate in Ningxia was favorable to improve the yield of winter wheat after returning farmland to forestland.

Flowering responses to light and temperature

Light and temperature signals are the most important environmental cues regulating plant growth and development. Plants have evolved various strategies to prepare for, and adapt to environmental changes. Plants integrate environmental cues with endogenous signals to regulate various physiological processes, including flowering time. There are at least five distinct pathways controlling flowering in the model plant Arabidopsis thaliana: the photoperiod pathway, the vernalization/thermosensory pathway, the autonomous floral initiation, the gibberellins pathway, and the age pathway. The photoperiod and temperature/vernalization pathways mainly perceive external signals from the environment, while the autonomous and age pathways transmit endogenous cues within plants. In many plant species, floral transition is precisely controlled by light signals(photoperiod) and temperature to optimize seed production in specific environments. The molecular mechanisms by which light and temperature control flowering responses have been revealed using forward and reverse genetic approaches. Here we focus on the recent advances in research on flowering responses to light and temperature.

Junction-temperature estimation in AlGaInP light-emitting diodes using the luminescence spectra method

This study proposes a practical method to estimate the junction temperature of AlGaInP LEDs using the luminescence spectra method.The peak wavelength shift of LEDs is due to the energy band gap shrinking.The temperature dependence of the bandgap of AlGalnP LEDs is derived from those of the underlying binary compounds A1 P,GaP,and InP.Based on this,a theoretical model for the dependence of the peak wavelength on junction temperature is developed.Experimental results on the junction temperature of AlGalnP red light-emitting diodes are presented.Excellent agreement between the theoretical and experimental temperature dependence of the peak wavelength is found.

PVDF/6H-SiC composite fiber films with enhanced piezoelectric performance by interfacial engineering for diversified applications

Piezoelectric silicon carbide(SiC)has been quite attractive due to its superior chemical and physical properties as well as wide potential applications.However,the inherent brittleness and unsatisfactory piezoelectric response of piezoelectric semiconductors remain the major obstacles to their diversified applications.Here,flexible multifunctional PVDF/6H-SiC composite fiber films are fabricated and utilized to assemble both piezoelectric nanogenerators(PENGs)and stress/temperature/light sensors.The open cir-cuit voltage(V_(oc))and the density of short circuit current(I_(sc))of the PENG based on the PVDF/5 wt%6H-SiC composite fiber films reach 28.94 V and 0.24μA cm^(-2),showing a significant improvement of 240%and 300%compared with that based on the pure PVDF films.The effect of 6H-SiC nanoparticles(NPs)on inducing interfacial polarization and stress concentration in composite fiber films is proved by first-principles calculation and finite element analysis.The stress/temperature/light sensors based on the composite fiber film also show high sensitivity to the corresponding stimuli.This study shows that the PVDF/6H-SiC composite fiber film is a promising candidate for assembling high-performance energy harvesters and diverse sensors.